Saturday, January 25, 2020
Effect of Ayurvedic Drug on Drosophila Melanogaster
Effect of Ayurvedic Drug on Drosophila Melanogaster Dr. Sonali Sengupta* Namrata Sain,Ã Lathika J,Ã Akshay Tharali Abstract:- The fruit fly Drosophila melanogaster known as a model organism is widely used in mammalian cellular and developmental studies. Its vast genome similarity with the humans has facilitated for various genetic and physiological studies. Ayurvedic medicine represents a traditional form of medication used to treat various human illness and anomalies. This paper aims to study the effect of an anti-paralytic ayurvedic drug on the physiological and behavioural pattern of locomotion defective and neurophysiology defective strain of Drosophila. This study will also help us to draw an analogy to the effect or action of these ayurvedic drugs on human system and further lead us to better understanding of the condition. Keywords:- Drosophila melanogaster, Ayurvedic , behavioural, physiological Introduction:- Drosophila melanogaster acts as an ideal species for model systems and drug interaction studies. Due to its feasibility for culturing and short reproductive cycle it is used in various genetic research prospectives. The drosophila genome on account of its similarity with the human genome can be studied extensively to identify certain genes involved in disease condition and also aid in understanding the various regulatory mechanisms that are associated with it. Study of drug interaction in Drosophila can be very well co-related to its effect on humans and therefore various drug interaction studies have been conducted in various conditions thereby relating it to the genotype. Drug interaction with Drosophila can be used to study its genotoxic effect as well as any rectifying effect on the expressed phenotype of the organism. Locomotion rhythm and neurophysiology defective mutants of Drosophila melanogaster exhibit both structural and functional abnormality and can be considered analogus to human paralysis condition owing to the non-functioning of neurons stimulating the muscles. The ebony (e11) mutants of drosophila show locomotor rhythm defect along with a defect in the electrophysiology properties of the neurons, muscles leading to the characteristic movement defect. This condition can be related to the paralytic condition in humans and drug interaction with these mutants can be used as a future way for analysis and cure of the condition in humans. Ayurveda has represented a field of medications and formulations that have been used to treat various human abnormality conditions in India. Ayurvedic medicine represents various treated plant extracts and formulations which contain certain important compounds that target the affected sites in human disorder conditions. These ayurvedic medicines can be considered as an example of medications which have their efficacy related to the genoptypic constitution of the subject. Various anti-paralytic ayurvedic drugs target the neuronal and muscular components of the affected condition. This paper aims at studying the effect of such an Ayurvedic drug on the locomotion and neurophysiology defective mutants of Drosophila melanogaster and relating it to the human complex disorder conditions. Materials and Methods:- 2 types of strains were used. 1.Canton-S: Drosophila melanogaster of Canton-S wild type strain were obtained from Dr. Kavitha Thirumurugan, VIT University. They were maintained, cultured and outbred in large population in optimum temperature in our laboratory. 2. e11 (Dmele11tm3) The ebony e11 mutants were obtained from NCBS, Bangalore. They were cultured on corn meal medium maintained at 24C. The mutants showed phenotypic characteristics of locomotion rhythm and neurophysiology defective. Drug:- The Ayurvedic drug used was Amukkara choorana purchased from a local ayurvedic medicine shop in Vellore in form of tablets .The main ingredient of this medicine is Amukkara or Ashwagandha (Withania somnifera). Amukkara Choornam has an anti-arthritic activity and it is a restorative and nervine tonic. Experiment:- The wild type flies were cultured in 3 types of food:- (i) corn meal medium without drug (ii) medium with 0.01g drug i.e 100microgram of drug for 100 ml.(iii) medium with 0.05g drug i.e 500microgram of drug for 100 ml. (iv) medium with 0.1g drug i.e 1000 microgram of drug for 100 ml. The e11 mutants were also cultured in corn meal medium with and without out drug of the above mentioned concentration of drug. To observe drug administration from larval stage, 30 Wild type larva were also culture in normal medium as well as in medium with the above mentioned drug concentrations. The larva were transferred using a thin paint brush and carefully planted on the medium and cultured at constant temperature. Assays:- 1. Survival Assay:-The wild type and mutant flies were cultured in normal and drug medium for 7days (1 week) and their rate of survival was measured. 2. Climbing Assay:-10 wild type and mutant flies were observed for their characteristic climbing ability in normal and drug medium. 3. Light Sensitive Assay:-10 wild type and mutant files from each category were exposed to a light source for 2-5 minutes and their anti-geotrophic behaviour was observed. 4. Polytene chromosome analysis:-Wild type larva were dissected and polytene chromosomes were observed by acteocarmine staining for any chromosomal abberations. The larvae were collected from both normal and drug medium which were dissected with a mounted needle on a glass slide under the microscope and the polytene chromosomes were removed from the salivary glands. The polytene chromosomes were then fixed using freshly prepared chilled fixative (Methanol: Acetic acid 3:1) and stained with acetocarmine dye. It was then washed with glacial acetic acid,cover slip was placed . Mounting was done and observed under microscope. RESULTS:- Rate of Survival:- Fig 1:- Graph representing the survibility assay of the Wild type and e11 mutant flies over a period of 7 days cultured in corn meal medium without drug and with drug at 3 different concentrations (0.01g, 0.05g and 0.1g per 100 ml) Fig 2:- Wild type and e11 mutant flies cultured in corn meal medium. Climbing assay:- Fig 3:- e11 mutant in 0.1g drug food showing static behavior (lower one) Light Sensitive Assay:- The light sensitive assay was performed on Day 4:- Wild type in normal food:- The flies showed anti-geotropic behavior i.e attraction towards light. 8 out 10 were attracted towards light Wild type in 0.01g drug food:- showed jumping movement and falling cycle. Wild type in 0.05g drug food:- Flies showed geotropic behavior i.e withdrawl from light source. Wild type in 0.1g drug food:- Flies show complete withdrawl from light i.e they prefer to stay in dark Mutant in Normal food:- On exposure to light it showed mostly static behavior with minimal movement and difficulty in climbing due to weak muscle strength. Mutant in 0.01 drug food:- Extreme static behavior and difficulty in moving. Mutant in 0.05g and 0.1g drug food:- Not viable. Fig4:-Wild type flies in 0.1g drug food showing withdrawl from light exposure. Polytene chromosome analysis:- Polytene chromosome analysis revealed no chromosomal abberations in the wild type flies post exposure to varied concentrations of drug DISCUSSION:- In the above study both wild type and ebony mutant flies were cultured in three types of drug medium with each medium having increasing concentration of drug. Both the wild type and mutant flies showed decrease in survival rate in food with drug concentration 0.1g as well as in 0.05g with a more potent decrease in the 0.1g indicating lethality due to the drug dose. So the drug concentration was decreased to 0.01g which showed no decrease in survival rate for the wild type flies whereas the mutant flies showed less decrease in survival rate indicating minimal concentration of drug may induce a positive effect on survival rate. The Climbing assay showed that the mutants in 0.1 and 0.05g drug food showed shibire behaviour and inability to cling to the wall thus inferring muscle weakness before the drug proved lethal. Whereas mutants in 0.01g drug medium showed reduced climbing pace and static movement but had a positive effect on survival rate. Wild type flies in drug food showed no change in initial days but depicted slow climbing rate in later days. But when the drug was exposed from the larval stage, it showed a positive effect on the climbing as well as jumping behavior. Thus it can be concluded that the if the drug is exposed to the organism from the larval stage it produces a better effect as compared with adult stage. Thus it may concluded that incorporation of the drug during the larval stage may produce a curable effect as compared to that during adult stage, but further studies need to be done. Light sensitive assay revealed that wild type flies in 0.05g and 0.1g drug food showed geotropic behavior and complete withdrawl from light respectively. Mutants in drug food showed mostly static response to light. This study aims at finding out the drug interaction with the defective gene thereby drawing an analogy with the human genome. The effect of these drugs on the drosophila genome may provide an analogy as to which gene may be affected in case of patients with paralytic or muscular disorders and may also provide possible means of therapy for the management and treatment of the disorders. REFERENCES:- In Vivo Effects Of Traditional Ayurvedic Formulations in Drosophila melanogaster Model Relate with Therapeutic Applications by Vibha Dwivedi et.al 2012. The effects of exogenous antioxidants on lifespan and oxidative stress resistance in Drosophila melanogaster by Tapiwanashe Magwere et.al 2006 Dopamine modulates acute responses to cocaine, nicotine and ethanol in Drosophila Roland J. Bainton et .al 2000. Mutant human torsin A responsible for early onset dystonia, dominantly suppresses GTPCH expression, Dopamine levels and locomotion in Drosophila melanogaster by O donnell JM et al 2011. Drug resistance of bacteria commensal with Drosophila melanogaster in laboratory cultures Sultan, R et al 2001. The pattern of campaniform sensilla on the wing and haltere of Drosophila melanogaster and several of its homeotic mutants by Eric S. Cole et al 1982. A gene necessary for normal male courtship, yellow, acts downstream of fruitless in the Drosophila melanogaster larval brain by Mark David Drapeau et al 2003. Tyrosine and catecholamine metabolism in wild-type Drosophila melanogaster and a mutant, ebony by Ross B. Hodgetts et al 1976. Neurophysiological defects in temperature-sensitive paralytic mutants of Drosophila melanogaster by Siddiq et al 201. Electrophysiological Correlates of Rest and Activity in Drosophila melanogaster by Douglas A Nitz et al 2002.
Friday, January 17, 2020
Car Rental Business plan Essay
The purpose of this business plan is to raise $300,000 for the development of a car rental agency while showcasing the expected financials and operations over the next three years. The Car Rental Agency Inc. (ââ¬Å"the Companyâ⬠) is a New York based corporation that will provide the rental of economy, standard, and luxury automobiles in its targeted market. The Company was founded in 2009 by John Doe. 1.1 Products and Services As mentioned above, the Car Rental Agency will be actively engaged in the rental of economy class, standard, and luxury vehicles for tourists and vacationers within its targeted market. A bulk of the Companyââ¬â¢s revenues will come from the daily rental charges for vehicle usage. The business will also recognize revenues from the sale of insurance services and gasoline charges to customers. At the onset of operations, the Company intends to have a leased fleet of 30 vehicles. The third section of the business plan will further describe the services offered by the Car Rental Agency. 1.2 The Financing Mr. Doe is seeking to raise $300,000 from as a bank loan. The interest rate and loan agreement are to be further discussed during negotiation. This business plan assumes that the business will receive a 10 year loan with a 9% fixed interest rate. 1.3 Mission Statement The Car Rental Agencyââ¬â¢s mission is to become the recognized leader in its targeted market for renting affordable vehicles to the general public on a daily basis. 1.4 Mangement Team The Company was founded by John Doe. Mr. Doe has more than 10 years of experience in the automotive industry. Through his expertise, he will be able to bring the operations of the business to profitability within its first year of operations. 1.5 Sales Forecasts Mr. Doe expects a strong rate of growth at the start of operations. Below are the expected financials over the next three years. 1.6 Expansion Plan The Founder expects that the business will aggressively expand during the first three years of operation. Mr. Doe intends to implement marketing campaigns that will effectively target individuals, tourists, and business travelers within the target market. 2.0 Company and Financing Summary 2.1 Registered Name and Corporate Structure The Car Rental Agency, Inc. The Company is registered as a corporation in the State of New York. 2.2 Required Funds At this time, the Car Rental Agency requires $300,000 of debt funds. Below is a breakdown of how these funds will be used: 2.3 Investor Equity Mr. Doe is not seeking an investment from a third party at this time. 2.4 Management Equity John Doe owns 100% of the Car Rental Agency, Inc. 2.5 Exit Strategy If the business is very successful, Mr. Doe may seek to sell the business to a third party for a significant earnings multiple. Most likely, the Company will hire a qualified business broker to sell the business on behalf of the Car Rental Agency. Based on historical numbers, the business could fetch a sales premium of up to 4 times earnings. 3.0 Products and Services Below is a description of the car rental services offered by the Car Rental Agency. 3.1 Daily Car Rentals The primary source of revenue for the business will come from the direct daily rental of the Companyââ¬â¢s fleet of approximately 30 vehicles. The Company will have three tiers of rentals including economy, standard, and luxury. Management expects that 75% of all rentals will fall into the economy or standard class. A limited number of luxury vehicles will be held on the lot for wealthy tourists and business travelers. Daily charges to clients will range from $49 to $99 per day depending on the type of vehicle they intend to rent. 3.2 Insurance Fees and Ancillary Services In addition to daily charges made to vehicle renters, the Company will earn secondary streams of revenue from the sale of additional insurance. This is an important secondary steam of revenue for the business as sales of additional car insurance will generate substantial gross margins for the Car Rental Agency. Additionally, the Company will charge substantial fees to customers that do not return the vehicles with full gas tanks. Approximately 25% of the Companyââ¬â¢s aggregate revenues will come from the sale of insurance and gas fees. 4.0 Strategic and Market Analysis 4.1 Economic Outlook This section of the analysis will detail the economic climate, the car rental industry, the customer profile, and the competition that the business will face as it progresses through its business operations. Currently, the economic market condition in the United States is in recession. This slowdown in the economy has also greatly impacted real estate sales, which has halted to historical lows. Many economists expect that this recession will continue until mid-2009, at which point the economy will begin a prolonged recovery period. However, Car Rental Agencies typically operate with a strong degree of economic stability as business travelers will continue to need vehicles for their business trip needs. 4.2 Industry Analysis Within the United States, there are more than 5,000 companies (that operate one or more locations) that provide daily car rental services to the general public. Each year, these businesses aggregately generate more than $20à billion dollars of revenue and provide jobs to more than 120,000 people. Aggregate payrolls in each of the last five years have exceeded $3.1 billion. This is a mature industry, and the future expected growth rate is expected to equal that of the general economy. As mentioned above, despite the currently high gasoline prices, the industry will continue to remain profitable as business travelers will continue to require rented vehicles during their business trips. 4.3 Customer Profile In this section of the analysis, you should describe the type of customer you are seeking to acquire. These traits include income size, type of business/occupation; how far away from your business is to your customer, and what the customer is looking for. In this section, you can also put demographic information about your target market including population size, income demographics, level of education, etc. 4.4 Competitive Analysis This is one of the sections of the business plan that you must write completely on your own. The key to writing a strong competitive analysis is that you do your research on the local competition. Find out who your competitors are by searching online directories and searching in your local Yellow Pages. If there are a number of competitors in the same industry (meaning that it is not feasible to describe each one) then showcase the number of businesses that compete with you, and why your business will provide customers with service/products that are of better quality or less expensive than your competition. 5.0 Marketing Plan The Car Rental Agency intends to maintain an extensive marketing campaign that will ensure maximum visibility for the business in its targeted market. Below is an overview of the marketing strategies and objectives of the Car Rental Agency. 5.1 Marketing Objectives â⬠¢ Establish relationships with airports and travel agents surrounding the target market. â⬠¢ Implement a local campaign with the Companyââ¬â¢s targeted market via the use of flyers, local newspaper advertisements, and word of mouth advertising. â⬠¢ Develop an online presence by developing a website and placing the Companyââ¬â¢s name and contact information with online directories. 5.2 Marketing Strategies Mr. Doe intends on using a number of marketing strategies that will allow the Car Rental Agency to easily target tourists and business travelers coming to the target market. These strategies include traditional print advertisements and ads placed on search engines on the Internet. Below is a description of how the business intends to market its services to the general public. The Car Rental Agency will also use an internet based strategy. This is very important as many people seeking local services, such as car rental agencies, now the Internet to conduct their preliminary searches. Mr. Doe will register the Car Rental Agency with online portals so that potential customers can easily reach the business. The Company will also develop its own online website, which will include functionality for people to book and pay for vehicle rentals directly through the Companyââ¬â¢s online platform. This marketing feature is common to most companies that rent cars to the general public. The Company will also place advertisements on major travel portals such as Expedia, Orbitz, and Travelocity. Mr. Doe will also develop relationships with local travel agents that will make arrangements for rentals among people that are traveling through the target market. 5.3 Pricing In this section, describe the pricing of your services and products. You should provide as much information as possible about your pricing as possible in this section. However, if you have hundreds of items, condense your product list categorically. This section of the business plan should not span more than 1 page. 6.0 Organizational Plan and Personnel Summary 6.1 Corporate Organization 6.2 Organizational Budget 6.3 Management Biographies In this section of the business plan, you should write a two to four paragraph biography about your work experience, your education, and your skill set. For each owner or key employee, you should provide a brief biography in this section. 7.0 Financial Plan 7.1 Underlying Assumptions â⬠¢ The Car Rental Agency will have an annual revenue growth rate of 16% per year. â⬠¢ The loan will have a 10 year term with a 9% interest rate. â⬠¢ The Owner will acquire $300,000 of debt funds to develop the business. 7.2 Sensitivity Analysis In the event of an economic downturn, the business may have a decline in its revenues. However, among business travelers, renting a car is a necessity. As such, the Car Rental Agency will be able remain profitable despite a drop off in tourist activity. 7.3 Source of Funds 7.4 General Assumptions 7.5 Profit and Loss Statements 7.6 Cash Flow Analysis 7.7 Balance Sheet 7.8 General Assumptions 7.9 Business Ratios Expanded Profit and Loss Statements Expanded Cash Flow Analysis
Thursday, January 9, 2020
Wednesday, January 1, 2020
Building information modelling - Free Essay Example
Sample details Pages: 21 Words: 6346 Downloads: 7 Date added: 2017/06/26 Category Statistics Essay Did you like this example? 2.1 Introduction As expressed in the Egan report (1998), the UK construction industry is a significant contributor to the domestic economy in the UK that it is simply too important to be overlooked. The construction process and its success are influenced by various factors and choosing the most effective investment to improve the construction process is a very important decision. Building Information Modelling has been said to represent a paradigm that will have comprehensive benefits brought to the construction industry (Eastman, 2009b). Donââ¬â¢t waste time! Our writers will create an original "Building information modelling" essay for you Create order Popov et al. (2010) claimed that the growing diversity of disciplines, professionals, tasks, events in respect of the management during design and construction stages of projects, plus the more competitive cost and more intense deadlines with higher quality expectations as well as the need for enhancing technology are the driving force of information modelling in the construction industry. Building Information Modelling, or better known as BIM is not; strictly speaking a new technology as it has been developing and used by other industry sectors since 1950s i.e. the automotive and aero plane industries. These industries have been way ahead of the AEC industry as for the past 20 years, fully utilizing the available technology for their industries (Augustsson, 2007). Subsequently, this literature review will assess and evaluate the historic and current information in respect of Building Information Modelling to enable an understanding on the past development of BIM, the benefits that it could offer to our construction projects as well as identifying the barriers entailing for the full adoption of BIM among the contractors in the UK construction industry. 2.2 What is BIM? As defined by BIMForum:- A building information model (BIM) is an object-oriented building development tool that utilizes 5-D modeling concepts, information technology and software interoperability to design, construct and operate a building project, as well as communicate its details (BIMForum, 2007). One common understanding to describe BIM is the building development tool that creates a three dimensional (3D) geometric model with computer softwares. The model then can be used to assist the design, construction and operational process and also acting as a communication tool (BIMForum 2007). Nevertheless a 3D geometric model wouldnt be sufficient to answer the demanding construction requirements at present. A BIM model contains a high level of intelligence which not just limited to a three-dimensional geometric representation of the building, (GSA, 2007) but also includes 5D modelling where the 4th dimension is referring to time element whilst the 5th dimension is referring to cost. In addition, as indicated by BIMForum (2007), there might be further development that is inclusive of procurement application which is the 6D as well as the operational applications which is the 7D. In general, a building information model is a digital representation, virtual representation of all the physical and functional characteristic of a building which also acts as a resource of information storage for the building which could be shared/used from the inception period and throughout the lifecycle of the building. 2.3 The past development and revolution of BIM Conventionally, constructing a building was merely the responsibility of the Architects and the Engineers, designing on papers and then the Contractors build it. Cyon Research (2003) stated that Construction projects have always been defined by various drawings and documents where at times might be in conflict with each other thus showing inconsistency. These inconsistencies are the typical issues that often aroused when the documents and drawings are maintained separately with different participants working on different or superseded documents. There will always be unanticipated field costs, delays and eventual lawsuits between various parties within a project team as a result of errors and omissions in paper based communication. According to Vinod Kumar (2009), the beginning of orthographic drawings and perspectives can be traced back as far as during the Renaissance era when Filippo Brunelleschi represented the plans in drawing format for Santa Maria del Fiore in Italy in order for the patrons to understand how the building would look like. Vinod Kumar (2009) further explains the evolution of systematic documentation from manual methods all the way till our presently available technology by dividing it into three phases: I phase Till early 1980s: Before 1980s the traditional way of creating design documents are through manually drawn lines representing building i.e. plans, sections, elevations and etc. II phase 1980s to Late 1990s: This was the period where major change took place from manual drafting towards computer aided drafting when computers were firstly introduce. There is more elaborated information as the complexity of buildings increased as well as more specialization in the design and construction process. Use of computers, especially for 2D drawings and reports are ground-breaking changes into the systematic Documentation. III phase Beginning of the 2K: With the buildings degree of complexity presently, the number of parties involved in the process of drawing production has also increased. In line with the development of technology there are also more introduction of more interrelated and integrated building system i.e. HVAC system, energy requirement and etc. The computer based technology has also been constantly updated to reduce errors that occur but nonetheless they are still merely the collections of manually created, non-intelligent lines and text. The diagram below shows the evolution from manual methods all the way till the introduction of new technologies. A previous study by Autodesk (2002) which correlates with Vinods statement, mentioned that in the early 1980s the Construction industry took one step forward when the architects began using PC based Computer Aided Design, CAD. It is said that the CAD system was adapted with ease by the Industry as it was initiated from the pin-bar drafting which the Industry was familiar with. Thus many construction documents and drawings were completed using CADD rather than being drafted manually on drawing boards. DWS files were then exchanged in replacement of paper drawings, from simple graphics to the information content on the building. The CAD files developed significantly, communicating the information on the building which plotted drawing couldnt. Following that Holzer (2009) also stated that in the late 70s and early 80s, CAD systems like RUCAPS was used where it operated in parametric environment enabling 2D information extracted from a 3D model. RUCAPS allowed multi user access and put f orward a new way in generating, distributing as well as retrieving building information which was different fromt he common drafting processes. Unfortunately the down side of this system was the high cost and slow speed of the system as well as its inability of producing more complex geometrical shapes. Nevertheless, some of the fundamental concept of RUCAPS can be found in the current BIM software such as Autodesks REVIT, Bentleys TRIFORMA, Gehry Techs DIGITAL PROJECT and etc. Nowadays, the use of BIM is very common within the manufacturing and aerospace industries where new products or product changes are modelled virtually for the assessment of design, performance and production. . We are also in the process of experiencing a similar revolution in the construction industry. BIM and other related technologies have emerged since the past decade and developing up till the present where they have been acknowledge as the platform for the design and construction of various projects (Shen, et.al, 2009). Nevertheless, FWCI (2009) argued that it is important to understand that BIM is not CAD+ or the Son of CAD as BIM functions in its own approach and discipline. BIM, acting as a single source entry for project team involves the process of generating, storing, managing, exchanging and sharing building information in an interoperable and reusable way. Generally a BIM system is a tool that enables users to integrate and reuse building information and domain knowledge through the lifecycle of a building Presently there are numerous BIM products on the market by various vendors. Autodesk Revit was considered as one of the leading BIM creation tools. Bentley Systems, Graphisoft, Vico software and Nementcheck are also currently very well-known in the market. They each provide various building model tools to design a building (Rosenberg 2006). With this technology, the information needed for a projects design, construction and operation are contained in a model digitally which is centralized and could be shared across all associated project stakeholders (COBRA, 2008). 2.4 Various understanding of BIM in the Industry At present there is a vast amount of information that is available in respect to the definition of premise of BIM. Holzer (2007) explained that even though the application of BIM becomes more accepted and common throughout the industry, but there has been a problem in agreeing the definition of BIM. The common definitions would be described as a method for project information management with the combination of non-geometry attributes with geometrical entities, or defined mostly by pointing out its capabilities for cost-control and to facilities management. Holzer (2007) continues to claim that because the term BIM is often used by vendors for their marketing strategies in order to promote their company software, the definition of BIM technology has become very confusing. On the other hand, Eastman et al (2008) has suggested that in order to deal with this confusion it is useful to describe modelling solutions that do not utilize BIM technology. This includes tools that create models containing only 3D data with no object attributes, models that do not utilize parametric intelligence, models composed of multiple 2D CAD reference files that must be combined to define the building as well as models that allow changes to dimensions in one view that are not automatically reflected in other views. Furthermore, another popular talk about issue within the industry is the multi dimension product models, the ability of BIM to provide multi dimensional application. (GSA 2007) has stated that 4D models represent 3D models plus time which include project phasing, construction scheduling whilst 5D models incorporate the costs elements. Nonetheless, Lee (2005) has identified the additional numbering of the dimension as nD modelling. Lee stated that nD modelling is an extension of the building information model that incorporates multi-aspects of design information required at each stage of the lifecycle of a building facility. On the other hand, in the year 2006, The Associated General Contractors of America (AGC) also published The Contractors Guide to BIM which touched on the issue in respect of the continuing usage of the numbering i.e. 6D, 7D, and etc has therefore acknowledged the extended application of the 3D tool as XD (AGC, 2006). This research is mainly focusing on the 3D mode ls with incorporation of time (4D) and cost (5D) elements. 2.5 Benefits of BIM There are many obvious benefits that BIM could offer to various parties including the owners, planners, engineers, estimators, designers and etc. It is understood that different stakeholders would value BIM differently. They may share the same information but have different responsibilities and uses on the model. From a Contractors perspective, BIM brings essential value for enabling virtual construction of the structure within a single source file (Hardin, 2009). As quoted from the BIM 2009 Smart Report, A model is Worth a Thousand Drawings. Contractors are making use of the intelligent model for assisting them with various activities i.e. planning construction sequences, cost estimations and bidding, conflict resolution and visualization project demonstration for client and etc (Neeley, 2010). The incorporation of intelligent data improves the models construction and post-construction realities, which also enables the contractor to get closer to the world of the designer (Sage soft ware 2008). The initial literature review has showed that costs are significantly reduced, time is saved and the quality improved. 2.5.1 Single source Model In conventional process, the Project Manager reviews the updated drawings and reflects any changes onto the schedule as the design progress. Many times the same information is entered into different program. Every repetition increases the probability of inconsistency and error occurrence. BIM on the other hand allow direct changes applied to the single model. As both designers and contractors have access to the model simultaneously, this corresponding process also enables them to reduce lead times which normally take place throughout the period of sending back-and-forth the documents. The collaborative environment contributes to a substantial time saving during pre construction. Extra coordination checks are also unnecessary because the information generated from the model will lead to fewer errors on site which normally is caused by inaccurate and uncoordinated information. In the case of any last minute design changes, addendums, clarifications and etc it could be altered and updat ed to the model automatically across the project team, from early design through completion (Hardin, 2009). These ensure that all parties are working with the latest information. With all the information contained within the BIM database it will definitely increase the efficiency between the Architect, Engineer as well as the Contractors. 2.5.2 The 3D Visualization Clash Detection The 3D visualisation capability of BIM models can be of great benefit as a means of testifying the workability and demonstrating aspects of the construction itself such as construction sequencing, logistics, access, storage and security (C3 System 2009). BIM allows for building twice which offers various benefits like improvement in Constructability, maintainability, cost estimate accuracy and etc. This reduces ambiguities before commencement of actual construction (Robert, 2005). The construction issues for layperson or non layperson are also made easier to understand as the 3D visualisation helps them to understand any constraints that the client had not made clear earlier, or were misunderstood (Furneaux and Kivits 2008). One of the major benefits which BIM could provide for contractors is clash detection. As identified by FWIC (2009), a hard clash is where more than one object is being designed to occupy the same space whilst a soft clash is where the objects in the design is too close to each other that there is no space for access or construction, or are too close that they have violated the building codes. The BIM system automatically detects and manages interferences which prevent possible delay or additional cost. The system could be set to run the check either the entire model or between certain parts of the model. 2.5.3 Construction Phasing (4D Simulation) Furthermore, one of the obvious BIM applications for improved time efficiency is construction planning. Hardin (2008) argued that the construction planning is one of the most important tasks and also one of the driving factors that determine the success of any projects. It is noted by Eastman et al (2008b) that Construction Planning and scheduling involves sequencing activities in space and time, procurement consideration, resources, spatial restrictions and etc. BIM is said to contribute in project planning solutions via the use of 4D simulation. Napier (2009) claimed that the conventional scheduling methods are labour intensive and is not easily understood by laypersons. BIM enables better communication and understanding how the schedule would impact site logistics as a result of the 4D construction phasing/planning tools that incorporate direct links to the design model, capturing spatial information which the traditional Gantt chart is unable to demonstrate. The 4D model incorpor ates time as added 4th dimension which enables the planner to visually plan and sequencing of construction activities with space and time consideration. Also, there might be specific materials and products selected from a potential range of refinements and substitutions that meet the project specification but may result in changes to some aspects of the design. As Neeley (2010) have stated, with the allowance of what ifs, a significant of cost, project risks and unnecessary waste could be saved by shifting the try-and-error process from construction site to the virtual environment on beforehand. Resource Allocation/Reducing Waste According to Egan (1998) in Rethinking Construction, within the construction industry almost 10% of materials are wasted and 30% of construction is rework. As mentioned by Articlesbased (2009) construction projects are very often planned based on resources availability as well as other external factors. With the 4D construction phasing/planning, the team members are able to understand the scope of work and the availability of various resources in order to optimize the resources and labour accordingly. In addition, Eastman (2008b) highlights that BIM is also accurate in providing the design model and material resources required for each segment of the work, it effectively assists in utilization of critical resources like labour, material and time during the building construction life cycle. With the improved monitoring of site logistics and the progress of project, the site management via BIM fosters just-in-time (JIT) of materials, plant/equipment and labours. Pre-fabrication Accuracy of design details are critical for determining the success of pre-fabrication, and a data-rich BIM model can have a positive impact and provide greater confidence on pre-fabrication. As BIM brings clarity towards a complex project, more contractors appreciate that BIM offers the advantage of effective coordination as the complexity level of project increases. The Design to Build and Build to Design concept improves accuracy for estimation and design specification for prefabricated elements thus reducing unnecessary wastage (BIMJOURNAL 2009). With greater confidence in the coordination process, many contractors are approaching more prefabrication options to help ease schedules. (BIM Smart Report, 2009) 2.5.4 Cost Estimates/schedule management From the costing aspect, Jernigan (2008) stated one of the main benefits provided by BIM is the accuracy in cost estimate during earlier stages. Conventionally, estimators have been relying on Excel spreadsheet to carry out their construction cost estimating (Autodesk, 2007), Eastman (2009b) then revealed that BIM include features for extraction and quantification of BIM component properties. By using a building information model instead of drawings; the takeoffs, counts, and measurements can be generated directly from the underlying model and the information can be linked to generate bills of materials, size and area estimations along with other related estimating information. Therefore the information is always consistent with the design and reduces the potential for human error or misunderstanding (Autodesk, 2007). This contributes to substantial time and cost saving as well as ensuring good quality of the BOQ. BIM offers the opportunity to develop more accurate cost estimates bas ed on actual elements (Hartman and Fischer 2008). Moreover, the linked cost information evolves in step with the design changes (Ashcraft, 2008). In addition, an indirect advantage that BIM could offered is the estimator would be given more extra time to bring in more value engineering, more time for risk evaluation and to more time to find any additional cost savings as the technology has taken up most of the grunt work from the estimator (Hague, No date).Using cost attributing features of the model to assess alternative design and construction schemes to enhance and improve the value engineering process; BIM certainly contributes in supporting the Contractor to present value for money to the Client. Neeley (2010) has claimed that the use of BIM and IPD (Integrated Project Delivery) is reducing project costs around 10%- 20% below construction costs compared to non BIM/IPD projects. 2.6 Case Studies No 1: One Island East, Hong Kong One of the popular examples of the actual Building Information Modeling Project that has been mentioned by various Authors in their research is One Island East Office Tower in Hong Kong which was developed by Swire Properties Limited. Together with the project BIM consultant, Gehry Technologies (GT) they began the process of working together to create a single, 3D electronic Building Information Model (Riese, 2006). The Project Details are summarized as follow: Project name One Island East, Hong Kong, China Project scope $300 million (approximate figure) Project Scale 70 Floors with 2 basement levels Total floor area: 141,000 m2 Typical floor area: 2,270m2 Schedule Construction Period: 24 months Expected completion: March 2008 Structure Reinforced concrete Exterior Aluminum curtain wall Owner Swire Properties Limited Contractor Gammon Construction Limited Architect Wong Ouyang (HK) Ltd Structural Ove Arup Partners HK Ltd Quantity Surveyor Levett Bailey MEP subcontractor Balfour Beatty BIM Consultant Gehry Technologies BIM Technical Support MTech Engineering Co. Ltd BIM scope Design coordination, clash detection, and work sequencing 2.6.1 Background Information The One Island East is a 308 meter high skyscraper with 59 stories of office space and two basement levels. The building has 70 floors in total which comprise of a sky lobby on 37th and 38th floors (Elkem Microsilika, 2009). It was Swires intention to achieve a high-quality design while improving construction time as well as cost savings by the use of collaborative, collocated work methods and integrated 3-D modeling tools. The initial objective was to save 10 percent on the cost with reduced time for construction (Shelden et al, 2008). The software tool chosen to create the BIM for this project is Digital Project with some of the benefits stated as follows: (Riese, 2006) Has automated clash detection and management Has a complete ME system routing tool. With built-in scripting function, enabling project requirements to be integrated for customization. Automated simultaneous file versioning and file sharing. Able to handle and manipulate large amounts of data Integrated with Primavera scheduling software with high interoperability 2.6.2 BIM Implementation (Pre-tender stage) BIM commenced after the schematic design phase. The office building has been pre-designed virtually using Digital Project by assembling up to 300.000 building components in a single master file. Almost all coordination issues were resolved using BIM. The design team, BIM consultant and Project Manager worked in one room for the first year. They also communicate with each other via a portal site for the BIM process. The DP software was capable of identifying geometric clashes and generates a list automatically. There were already several clashes and errors identified and resolved before tendering and construction. The DP tool also measured most of the quantities automatically which reduced the time and effort compared to manual take off. Also, the quantities were linked to the BIM which automatically updates when changes were made. 2.6.3 BIM Implementation (Tendering Stage) The model was provided to all tenderers which enabled them to have confirmation on the bill of quantities using the model without having to measure the quantities manually. As a result, tender process improved significantly with lower cost estimates and more accurate quantity takeoffs. 2.6.4 BIM Implementation (Post Tender Stage) Gammon Construction Limited, which was the contractor awarded for the project had full responsibility for the BIM model and began the development of highly accurate and detailed 3D BIM model for construction, ensuring that all 2D information would be firstly scrutinize in the 3D prototype before it went to the site. 2.6.5 BIM Implementation (Construction) During the construction period, the BIM model became the main visualization tool for the coordination of various project elements. There were full time modelers that assisted with the clashes identification and coordination issues where the design solutions were then incorporated into the model. A few subcontractors also participated in modeling their parts of work. 4D simulation was one of the main factors for the success of the OIE project. It was used extensively for improving construction sequence and managing risk. 2.6.6 Outcome There were more than 2000 clashes and errors were identified prior to bidding and construction stage, which resulted significant cost savings. The figure below is an example of a clash that has been detected between an electrical cable tra y and an air supply duct. Without BIM it wouldnt have been detected until the actual construction taken place which might potentially cause additional cost and time to the project. According to Shen et al.(2009), the geometric coordination off the design prior to construction is thought to achieve 10% cost savings whilst construction process modeling is thought to contribute further 20% cost savings on the construction. Gammon Construction has also reported that Construction Process Modeling saved the project at least 20 days. This project was awarded the American Institute of Architects 2008 BIM award for design/delivery process innovation. 2.7 Implementing BIM and the Potential Challenges From section 2.2 above it is demonstrated that BIM has brought numerous advantages and benefits to the industry. However there are also challenges and barriers that to be overcome before the full capability of BIM could be demonstrated and subsequently fully enjoyed by the industry stakeholders (Furneaux and Kivits 2008). In the very traditional and fragmented building industry, new technologies are not easily introduced. It should be noted that when a new technology is introduced, there will be a certain period of time in which the claims about the potential of the technology needs to be examined, tested and verified particularly the AEC industry which is known for the very long adoption periods of promising technologies (May et al. 2005; Salazar et al. 2006). Even though the technology of BIM is readily available and rapidly maturing but the adoption of BIM is much slower than anticipated (Fischer Kunz, 2006). Gillis (2008) made the criticism indicating that UK appears to be a more conservative and over protective country that demands proven effectiveness before considering adoption of new technology whilst Counties such as Norway, Sweden, and US attempts to proceed with new technology without 100% confirmation (Simon Gillis, 2008). As criticised by Prather (2007), most of the time, our professional would take the wait-and-see approach towards BIM. This is echoed by Safe software (2008) stating that our industry would mostly accept BIM only when the risk level has dropped and a clear return on investment is made known to the industry. Moreover, in these recessionary times, the money to spend on technology has got to have a good business case. The current UK industry inhibitors include contracts that has not promote working in collaboration, no external incentive for innovation, no motivation for parties to seek ways to deliver a better or quicker product and etc (Steve Dunwell, 2008). 2.7.1 Installation and operation Cost Eastman (2009) has highlighted one of the barriers to adopting BIM is the cost associated with the implementation. It is said that implementing new technology like BIM requires additional cost in respect of purchasing new software and hardware packages, training as well as changing the work processes and workflows. Also, if there are no technical expertises available within the organization, there will be a need to engage with external consultants to train employees prior to applying BIM within the organization which accounts for additional cost as well (Furneaux and Kivits 2008). Corresponding to what Eastman (2009) as well as Furneaux Kivits (2008) have said, a research done by Suermann et al. (2009) revealed that the whole installation of BIM for an organization is a costly plan when done at on one occasion, and even greater when done for several installations simultaneously for different projects. In addition, Suermann et al (2009) findings showed that there has been company which have had to increase their effort and cost allowance to do BIM due to the high learning curve. Apart from that, there is also an implication for procurement policy where consideration needs to be given to the additional funding for the development of BIM models in the first instance. The large size of BIM files will involve a different system for data sharing i.e. real time access to the BIM database between firms which are geographically distant and high speed internet connectivity will be essential (Kiviniemi et al., 2008 p.64). This would constitute extra cost for the operation of BIM. Furthermore, in order to reduce the risk of data corruption, sabotage, and loss; it is important to pay any indispensable cost associated to ensure data stability and security. 2.7.2 Embracing BIM throughout the entire supply chain Another apparent factor that has caused BIM taking the back seat is lack of commitment from the higher level of the supply chain. According to Oberle (2009), the transition to BIM requires support and commitment throughout the supply chain from top to down of an organization. In addition, The Crawley Schools PFI project in West Sussex has revealed the benefits which they have gained with the implementation of BIM but simultaneously also addressed one of their main barriers in implementing BIM was the reluctance of the supply chain in embracing this new technology, stating that some conservative individuals did not believe the benefits that BIM could offer thus were hesitant to undertake this new approach (Constructing Excellence, 2010). It is also noted that some Contractors that have too much existing workload might give the excuse that they dont have enough time to try out new technology. As quoted from Dunwell (2009), Old habits die hard. Most workers are reluctant to step out from their comfort zone and believed that their current handling approaches towards their projects are better than satisfactory. Apart from that, as indicated by Owen (2009), a very significant gap between conventional process and new technology that the industry is facing at present is the dependence of 2D drawings as a means of official information correspondence. Owen explains that in order to solve this problem there will need to be a change by clients and regulatory authorities, as well as the remaining members of the supply chain. Nevertheless, this will put BIM in a challenging position, attempting to accommodate the different levels of technology adoption and competency across the various sectors within the industry especially when progressing from few leading organizations to a majority of the construction industry and its stakeholders. 2.7.3 BIM Complexity/Familiarity for Early Adopters The size and complexity of the files that BIM system create might be a big challenge for early adopters of BIM especially when dealing with complex and big scale projects where fully loaded central BIM project database management is crucial (Howell, 2009). As a result earlier users which are not familiar with BIM would tend to default back to exchanging documents rather than working from a single model (Batcheler and Howell 2005). Suermann et al (2009) have emphasized that producing 2-D plan sets using BIM will not offer any advantages over using any CAD application to perform the same function. Unfortunately, it is still not possible to entirely stop the team members from defaulting back to the conventional process i.e. sharing information via exchanging documents in pdf, dwg and etc instead of sharing intelligent objects from the model, which goes against what BIM is seeking to achieve in the first place (Batcheler and Howell 2005). Unless contractors have a means to utilized BIM t hemselves, otherwise the development of BIM will be exceptionally slow and we will limp along with incomplete integration. 2.7.4 Interoperability of BIM BIM is obviously an important subset and the intelligent objects are a key enables, but the critical ingredient for BIM is interoperability, which is the ability to interact and coordinate as a consistent representation of the same building for each of these purpose-built models. The sharing of information between the different BIM models is critical to the success of BIM (Howell, 2009). Different uses of BIM may require different software applications to utilize the model; hence BIM requires software to be interoperable (BIMForum 2007). Synchronisation issues, project management, partial model exchange and software interfaces, all requires high interoperability and would definitely appreciate further research (Kiviniemi et al. 2008 p.64). As BIM is undergoing advance development and more new tools being introduced, interoperability has become an increasingly important issue. A recent studies conducted by McGraw Hill Construction showed that eight in ten BIM users say there is a sign ificant need to improve interoperability (Young, et al., 2009). The software packages from different vendors might not always interface with each other which can lead to information exchange problems, therefore the development of BIM could possibly be hold back as a result of the diversity of software providers. In order to mitigate this issue, interoperability and connectivity issues should be agreed as early as possible (Constructing Excellence, 2010). The expectation after implementing BIM is that everyone on the project team now will adapt a uniformity of one BIM system. Nevertheless according to Howell (2009) project teams comprise a collection of different companies, each of which has their own preferred and trusted software applications for design and management of projects. The structural team may be using Tekla, the architectural model may be built using Revit, the electrical contractor may use Bentley and HVAC engineers may deploy Graphisoft. These applications do not speak directly to each other and so collaboration issue might occur (FWCI, 2009). Apart from that, Dean McClendon (2007) also stated that it wouldnt be possible for one 3-D CAD software to include all functions i.e. cost estimating program and the specification writing program. Hence, separate programs would be needed and to have access to the common database. It is very rare that single technology is being used on any one building project between different companies and/or across all phase of the project lifecycle (Howell, 2009). But the various programs developed by different companies would be an issue for interoperability that needs to be resolved. However, looking from the positive side of this issue, The Industry Foundation Classes (IFCs), developed by the International Alliance for Interoperability (IAI), has introduced rules and protocols to help resolving interoperability issues. It provides the consistency in determining how the data representing the building in the model are defined along with the agreed specification of classes of components which foster the development of a common language for the construction industry (IAI, 2004). Still, another major issue arouse from the BIM model is the technological interface between design and construction companies. In order to co-create a virtual model the programs and file formats must be compatible. All associated companies must be capable of opening and editing the BIM model. However, if the additional or altered work on virtual model is unable to be opened or edited by any of the companies across the supply chain then the implementation of BIM is said to have failed (Furneaux and Kivits 2008). 2.7.5 Legal Issues and Contractual Relationships In any construction projects, one of the most important issues that must be addressed is the contractual or legal matters associated with the projects. According to Thompson (2001), the first legal issue that needs to be considered in a project that utilizes BIM is the ownership of BIM data and how to provide protection via copyright laws. As there are multiple parties contributing proprietary information to the project hence there is no simple answer to the question of data ownership; it requires a unique response to every project depending on the participants needs. As discussed by Rosenberg (2006), licensing issues might arise if any elements of the data contained in the model are used on subsequent projects. Therefore, this issue must be properly addressed in the contract documents to prevent any possible disputes from occurring. Another issue highlighted by Miner Thomson (2006), is the person accountable for the control of the data entry into the model that would need to take up the responsibility in case of any inaccuracies. Individuals carry a huge risk taking the responsibilities to update the BIM model and ensuring its accuracy. It is noted that proper negotiation needs to be carried out in respect of the indemnities by BIM users and the offer of limited warranties as well as disclaimers of liability by designers. All these issues need to be resolved before BIM technology could be implemented. Without any proper legal documents incorporating clear and agreed scope of responsibilities, if the model turns out to be faulty at later stage, the project team will most certainly start pointing fingers to each other, shifting the liability among each other (Ashcraft 2006). This might lead to poor relationship between the engineers, architects and contractors which prevents collaborative working atmosphere. At the end of the day it is the end product (the building) that suffers from delay, poor quality, additional cost and etc. In a typical BIM contract, the three key players are the owner, the design team and the contractor. For the contractor in particular, Contracts on BIM project is important defining his ability to influence collect and share the data throughout the projects life cycle (Hardin, 2008). Nonetheless, according to Ashcraft (2008), the legal aspect for Building Information Modeling at present still fails to keep up with the development of it. The implications of BIMs have just started to be recognized and only limited solutions have been developed to address the legal issues associated with it. Lack of standard contract documents hinders development of BIM. Liability concerns have lead industry professionals, to contractually separate the building information model, hence thus stripping the greatest benefits that BIM offers. Nevertheless, there has also been a research findings which is in contracts with what previous authors have said. The BIM Smart Report have showed that the legal issues which were once one of the main concern of the users as illustrated in past studies has now slowing fading (Young et al., 2009). 3.0 Conclusion from theoretical Analysis BIM is the future but at present there is still confusion about what it is and how it should be fully utilised and implemented in order to enjoy the benefit it brings. Using its three dimensional capability to produce visualisations is becoming widespread, however, limitation of its use is not exploiting the true potential for providing information about the building and its construction. BIM must meet the needs of the users of the content of the BIM (as distinct from the users of the BIM software) and, by definition,must be totally integrated(CPIC, 2009). BIM is not just merely about purchasing and installing the softwares (Fishking et.al 2009). Eastman (2008b) criticized that many people within the industry believed that once they have purchased the software from the vendors then they are BIM-ing. But it is certainly not the case. BIM as explained by Eastman (2008b) is bout software and process. This was then further reinstate by Fishking et.al (2009) explaining that implementing BIM involves dramatic changes in the current business practices as well as cultural and behavioural transition of the industry, changing the individuals way of thinking about working in collaboration with and relating to various parties in project planning and construction (Fishking et.al 2009). Thus, investigating the challenges/barriers as identified in literature would contribute in accelerating the adoption of BIM in the industry especially for contractors. It is essential to interact with the construction industry, investigating which factor is on the d rivers seat that has the biggest impact in implementing BIM. It is also important to establish the benefits that BIM could possibly bring to the Contractors and to obtain the Contractors perception towards these three letters by comparing the primary data findings with the secondary data result, whether to reinstate or to oppose the findings from Secondary data.
Subscribe to:
Comments (Atom)