Objectives And Functions Of Materials Management Construction Essay Site material management is a scientific technique. Materials Management is the process of planning, implementation and control of field and office activities in construction. The materials management goal is to ensure that building materials in their perspective when you need to.Materials management system attempts to ensure that the correct quality and quantity of material is appropriate, purchase, delivery and on-site processing in a timely manner and at a reasonable cost.Materials management system attempts to ensure that the correct quality and quantity of material is appropriate select , purchase, delivery and on-site processing in a timely manner and at a reasonable cost.So Materials management is an important element of project management. The material shows a major cost in the construction, thus reducing procurement costs to improve the opportunity to reduce the cost of the entire project. Construction projects, building materials fees accounted for 60 to 70% of the project cost. A reasonably organized planning, supply and use of building materials, construction materials from the production companies enter a construction according to the variety, quantity, quality, duration, reducing the transfer of part ofprevent the backlog of waste, shorten the construction period, accelerate the construction speed, reduce the cost of the project is important. 2.1 Scope of Materials Management It was referring to the various functions of materials management of the materials management coordination of various departments of manufacturing enterprises. Once the material procurement and brought by the organization, its value continues to increase other costs of materials required for the sorting, carrying materials in inventory, maintenance and management costs must be allocated to the cost of materials before entering into a product or converted to other form. In order to save the cost of all the materials management company has taken a clear method to determine the amount of material is ordered, the number is stored as inventory and in-process inventory. In order to reduce the cost of materials and other costs, there must be effective and efficient management of materials technology, it must be dynamically adjusted with changes in demand and production. 2.2 Objectives and Functions of Materials Management Primary objectives Which can be classified as: (i) Efficient materials planning (ii) Buying or Purchasing (iii) Procuring and receiving (iv) Storing and inventory control (v) Supply and distribution of materials (vi) Quality assurance Secondary objectives there can be several secondary objectives of materials management. Some of them are given below: (i) Efficient production scheduling (ii) To take make or buy decisions (iii) Prepare specifications and standization of materials (iv) To assist in product design and development (v) Forecasting demand and quantity of materials requirements (vi) Quality control of materials purchased (vii) Material handling (viii) Use of value analysis and value engineering (ix) Developing skills of workers in materials management (x) Smooth flow of materials in and out of the organization Achieve all these goals, it is necessary to establish harmony and good coordination between all employees of the materials management department. 2.3 Components of material management 2.3.1 Material supply and management Through market research, and look for the qualified materials The scope of inspections, investigations should first production and management vendors. One is the audit inspection material production and operation of the main body of all kinds of production and operation procedure is a complete range; The second is on-the-spot investigation enterprise production scale, management concept, sales and after-sales service, etc; The third is mainly studies the enterprise of quality control system, whether it has national and industry product quality authentication, material quality in the similar products is to belong to the general, intermediate or high-grade, etc. Another study visits range is building industry. Through the understanding of the building industry, information obtained a more accurate, more careful, more comprehensive. Generally speaking, really good quality materials will get architectural recognition, inferior quality of materials will be people spit on. By understanding building industry, can be more accurately master the material manufacturer enterprise reputation, product quality, price condition, the post-sale service, etc. The material the approach test Acceptance warehousing must ask the supplier of building materials security record to prove. The material inspection units must have the appropriate testing facilities and capabilities. Materials management in the construction process The central task is to check the use of the materials management process to ensure the quality of the material entering the construction safekeeping of materials approach, strict, reasonable use of a variety of materials, reduce consumption, to ensure the realization of the management objectives. 2.3.2The price of materials management 1. Control of the market, reduce the price of materials Control of the market, the market price is the extensive collection of materials. Material price information-gathering process, price information collection is in the building materials market, the material origin, the course of the investigation. The acquisition price information must be appropriate to the actual situation of the market to reflect the general level of prices of materials. Investigation and collection of price information for engineering materials, covers a wide range, heavy workload, is a complex information system. 2.Make full use of the market, reasonable arrangements for transportation Freight expenditures are important factors that constitute material procurement costs, save on shipping costs, reduce material procurement costs. Therefore, to consider the following aspects should consider the problems of the transport distance transportation cost savings: material when ordering. In the case of material quality, performance can meet the material procurement program, and almost equal to the price of materials, it should go to the nearest location away from the construction site procurement; material as a transport in place, to reduce secondary unlucky and handling costs. Take reasonable mode of procurement Doing so supply, storage, integration, reducing both parties arguing back and forth; owner can reduce material prices, reduce the project cost; course reasonable supply mode according to specific circumstances. 2.3.3 Material storage issue management Specifically the Treasury, proper storage. Identified clearly, classified storage In addition to the release of the material, whether by the Ministry branch or the issuance of project department warehouse supplies, should implement the principle of first-in, first-out project materials consumed should be read in conjunction with the segment and sub-project accounting, strict implementation of quota / fixed picking system must be opened by the project construction personnel before construction sign limits pick lists limit pick lists must fill part requirements essential items. Valuables and a larger amount of items, multiple payment based on usage, with picking small ticket points. Easily damaged goods, the material need for more detailed experience exchange members issued by the recipients of the two sides to sign off on the certificate. Material need generated from site Material ordered in the store Indents is generated Check availability in the store Check for the balance items Vendor selection from the approved list of vendors from the client Material inspection from the received stock Rejection of the unacceptable stock Issue of material to the concerned department Fig.1 process of material management Sources: National Conference on Recent Trends in Engineering Technology 2.4 Advantages of Materials Management Materials management to create a niche in many organizations, which have achieved a comprehensive materials management. These organizations often enjoy the following advantages: The better accountability part of the material, as well as other departments and no one can blame others. As materials management by a single authority, which can lead to better coordination, because it became the central point of any substance-related problems. Materials management departments to ensure a better quality materials provide a request in a timely fashion department. This can lead to a better performance of the organization. A materials management system is usually controlled through a system, therefore, can help decision-making related to the material in the organization. An indirect use of materials management is the development of good quality material, ethical and moral standards in an organization. Comment and evaluate the existing site layout relation to the positioning of the material on the construction site and identify possibles Construction site materials should be placed according to the requirements of safe and civilized construction program to be trimmed and decorated. Temporary construction water, electricity, roads, completed construction requirements of the standard. For field use reasonable construction plane layout should be structured to minimize occupied by construction land, the layout is compact and reasonable, and at the same time do field capacity neat and clean, the roads are wider, in line with the requirements of fire safety and civilized construction. The construction process to avoid multiple trades in the same venue, the same area for construction and mutual restraint, mutual interference. â-ª Keep work areas free from rubbish and obstructions â-ª Maintain all floor surfaces safe, suitable and free from slip or trip hazards â-ª Ensure floor openings covered or otherwise fenced off â-ªMaterials are properly stacked and stored safely Keep all passageways in good conditions â-ª Unobstructed and clearly defined â-ª Provide adequate lighting â-ª Ensure clear sightline at breaks and corners Stacking of all materials: â-ª Ensure the proper heights and correct stacking â-ª Allow sufficient space for moving stock â-ª Store materials in racks/bins â-ª Keep shelves free of rubbish â-ª Keep floors around stacks and racks clear â-ª Check drums and ensure pallets in good repair â-ª Heavier items stored low and without danger of falling objects â-ª Avoid sharp edges and provide safe means of accessing high shelves Site manager may face the following problems: Construction site temporary building (office) located in work area and near the waste materials faced with many unsafe factors and noise pollution. The area of construction waste, stored waste can not be transported out of the site.such as all solvent waste, oily rags, and flammable liquids,Scrap wood or chips, saw dust waste, and paper bags or cartons. If you accidentally cause a fire, then there will be heavy casualties. Most construction workers are exposed to excessive construction noise. One can get tinnitus, a ringing sound in the ears, or a temporary loss of hearing. Exposure to longer period can cause tiredness and nervousness. Concrete batching plant away from the material stores. It should be set in a near vertical transport machinery, as much as possible to reduce the concrete, mortar horizontal transport distance. Reduce transportation costs and save time. Store setting Concrete store should choose the higher ground, drainage, close to the batching plant. Inflammable and explosive materials shall not be mixed with other material. Inflammable and explosive materials warehouse layout should comply with the fire and explosion safety distance requirements. Proposed new site layout to improve the existing site layout mess hall temporary building (office) Workers Dormitory toilet Water Supply Site Entrance Double storey terrace Semi-detached houses Power supply Site exit Timber store Reinforcement Steel store Scaffold store Cement store Concrete batching plant Material store Waste material Suggestion/recommendation that will give strong impact on the material management process in the future based on the case study Responsibilities: Provide guidance, interpretation and direction to Major Projects staff regarding the Major Projects Procurement material standards and procedures Assist in Procurement orientations and on-boarding of Major Projects staff Review and provide improvement recommendations for Project Procurement Strategies and Plans Lead the development, implementation and management of policies, procedures and templates supporting the continuous improvement of material management within Major Projects Collaborate with Business Unit Procurement, Project Controls, Accounting, Construction, Engineering and Project Execution personnel to accurately understand capabilities in terms of systems and processes Outline material management procedures through the development of process flow maps Prepare draft and final assessment reports of material management findings First, the general requirements 1. Stacking of construction material should be based on the amount of size, duration, supply and transportation determine dosage, use a long time, supply transportation is convenient, it should be phased in. approach to reduce the yard and warehouse space; 2. Construction site of a variety of tools, components, materials piling must be placed in accordance with the provisions of the position of the planar four Figure; 3. Position should select appropriate, easy to transport and handling, minimize secondary transportation; 4. Higher ground, solid, flat, backfill compaction in layers, have drainage measures to comply with the requirements of safety, fire; 5. Should be stacked according to the varieties, specifications, and set up the obvious signs to indicate the name, specification and origin; 6. Various material items must be stacked neatly.  Second, the main material semi stacked 1. Large tools, should one side alignment put; 2. Reinforced should be neatly stacked, square wooden paving should not be placed in a wet and exposed to rain shower; 3. Brick should be small code into the stack, are not allowed to ultra-high from trench not less than 0.5m, to prevent collapse; 4. The sand piled cube, stones should be different diameter sizes are stacked into a cube; 5. Various templates should be stacked neatly classified according to specifications, the ground should be flat solid, stack height generally should not be the ultra-high 1.6m; the large template stored specifically designed to save shelf should be placed two large template should be used for face-to-face storage when stored floor construction, shall meet the homeostatic angle and reliable anti-dumping measures; 6. Concrete component stacking space should be solid, smooth, specifications, models stacked skids position to be correct, to be up and down to align the the multilayer components of skids, the pile position are not allowed to ultra-high; the concrete blocking plate should be established insertion of frame interpolation put frame to be welded or lashing firmly to prevent collapse. Conclusion Construction site materials management is one of the important link. To strengthen the management of the site layout, according to the different construction stages, materials and supplies changes, design changes, and adjust the position of the stockyard site in a timely manner, and keep the roads open, reducing the second out of luck. Strict accordance with the arrangement of stacked material with a flat-screen piles into the line, always clean up debris and garbage, and maintain the site, roads, tools and containers clean. The construction site must be carried out by the allied materials on-site materials management, material must pass the examination certificates; member of the staff of the material running configuration to enable the production and management of working prevail. Materials management for the enterprise has an extremely important significance.In a certain period of time, material resources and funds are always wired, good materials science management can promote cost reduction.Which time the minimum material consumption, to the maximum economic benefits.
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Implement Synthesizable Square Root Algorithm On Fpga Engineering Essay The main objective of this paper is to implement synthesizable square root algorithm on FPGA. As square root function is not synthesizable on Silicon, this paper proposes optimized non restoring square root algorithm for unsigned 8 bit number on ED2C20F484C7 device in Cyclone II family. This algorithm is implemented in gate level abstraction of Verilog HDL. The basic building block of the design is CSM (Controlled Subtract Multiplex) block. It makes use of only subtract operation and append 01 which is an improvement over restoring algorithm. Keyword: FPGA,CSM,Verilog HDL,fixed point Introduction The square root function is a basic operation in computer graphic and scientific calculation application. Due to its algorithm complexity, the square root operation is hard to be designed in digital system. As known, digital system has been used in daily life or industrial purpose that may have been in need of square root operation to fully execute its functions. Scientists have developed various algorithms for square root calculation. But the implementation of algorithms is difficult because of their complexities and thus results into long delays for its completion. There are two main families of algorithms that can be used to extract square roots. The first family is that of digit recurrence, which provides one digit (often one bit) of the result at each iteration[6]. Each iteration consists of additions and digit-by-number multiplications (which have comparable cost) Such algorithms have been widely used in microprocessors that didnt include hardware multipliers. Most of the FPGA implementations in vendor tools or in the literature use this approach. Second family of algorithms uses multiplications. It includes quadratic convergence recurrences derived from the Newton-Raphson iteration [5]. The digit recurrence approaches allow one to build minimal hardware, while multiplicative approaches allow one to make the best use of available resources when these include multipliers. Also there are estimation method and digit-by-digit method. Digit-by-digit method is classified into two distinct classes: restoring and non- restoring algorithm [1]. In restoring algorithm, remainder is restored in the regular flow. So its implementation needs more hardware. Compared to the restoring algorithm, the non restoring algorithm does not restore the remainder, which can be implemented with fewest hardware resource and the result is hardware simple implementation. It is most suitable for FPGA implementation. Restoring and non restoring square root calculation Restoring Algorithm Step 1: If it is a 2n bit number then divide it in a group of 2 bits Step2: Subtract 1 from the first 2 digits (starting from MSB) Step3: Whenever the result of the subtraction is positive then the developed root is 1 otherwise 0 Step4: Whenever the result is negative, write it as it is. We have to restore the wrong guess by appending 01 and guessed square root. Step5: Now take the next two digits Step6: Append 01 (to be subtracted from next two digits of dividend) and guessed square root to subtract from the remainder. Step7: If the result of subtraction is negative then restore previous remainder by adding wrong guess by appending 01 and guessed square root. Step8: Every time guessed square root has to be updated while appending 01. Step9: Continue the steps until the group of two digits end 1 0 0 1.1 0 1 0 01 01 11 01.00 00 00 00 01 00 01 take next two digits from dividend 1 01 Append 01 Negative value 11 00 + 1 01 0 0 01 11 -10 01 11 10 Negative value + 10 01 01 11 01 10 00 01 11 00 00 10 01 01 01 01 1 00 10011 01 1011111 + 1001101 010110 00 010011001 000010111 00 100110101 1100100111 Figure 1: The example of restoring algorithm to solve square root B. Proposed Modified Non Restoring Algorithm A little modification in non restoring algorithm makes calculation faster. It uses only subtract operation and appends 01. It uses n stage pipelining to find square root of 2n bit number. The following algorithm describes the modified non restoring square root algorithm. Step1: Start Step2: Initialize the radicand (p) which is 2n bit number. Divide the radicand in two bits beginning at binary point in both directions. Step3: Beginning on the left (most significant), select the first group of one or two digit (If n is odd then first group is one digit ,else two bits) Step4: Select the first group of bits and subtract 01 from it. If borrow is zero, result is positive and quotient is 1 else it is 0. Step5: Append 01(to be subtracted next two digits of dividend) and guessed square root to subtract from remainder of previous stage Step6: If result of subtraction is negative, write previous remainder as it is and quotient is considered as 0, else write the difference as remainder and quotient as 1. Step7: Repeat step 5 and step 6 until end group of two digits. Step8: End 1 0 0 1.1 0 1 0 01 01 11 01.00 00 00 00 00 01 00 01 take next two digits from dividend 1 01 Append 01 11 10 01 01 11 01 100 01 11 00 00 1001 01 001011 00 1001101 00101100 00 10011001 0000010111 00 100110101 001011100 Figure 2: The example of modified non restoring algorithm to solve square root Basic Building Block for Non restoring algorithm Inputs of the building block are x,y,b and u while d and b0(borrow) are outputs. If b0=0, then d b0=( ~ x .y)+(b.~x)+(by); d= (~x.y.~b.~u)+(~x.~y.b.~u)+(x~y.~b)+(x.u)+(x.y.b); csmblock.jpg Figure 3: RTL schematic of CSM block The generalization of simple implementation of non restoring digit by digit algorithm for unsigned 6 bit square root by array structure is shown in Fig.4. Each row of the circuit executes one iteration of non restoring digit by digit square algorithm, where it only uses subtract operation and appends 01. Figure 4: Pipelined structure of 6 bit unsigned square root number The design can be optimized by minimizing the logic expressions and can be implemented by modifying CSM block. The specialized entities A,B,C,D,E,F,G and H are derived from CSM block and are defined as follows: For csmA, ybu = 100 b0 = ~x d = ~x For csmB, yu = 00 b0 = ~x.b d = ~x.b + ~b.x For csmC, u = 0 b0 = ~x.y + ~x.b + y.b d = ~x.y.~b + ~x.~y.b + x.~y.~b + x.y.b For csmD, yb = 10 b0 = ~x d = ~x.~u + x.u For csmE, y = 0 b0 = ~x.b d = ~x.b.~u + ~b.x + x.u For csmF, xy = 00 b0 = b d = b.~u For csmG, xyb = 010 b0 = ~x d = ~u For csmH, xyu = 000 b0 = b Figure 5: Optimized Pipelined structure of 8 bit unsigned square root number Results and analysis The Non Restoring algorithm can be implemented with least hardware resources and the result will be the faster than restoring square rooting techniques. The source code is implemented in such a way that it can be extended according to users requirement to calculate complicated square root in FPGA. Figure 6: Simulation result of 8 bit square root using non restoring algorithm The DE1 kit has 4 seven segment displays only so the maximum number which can be displayed is 9999d and also it doesnt have a decimal point. Hence output obtained is less precise if one of the displays is considered as a decimal point. Table 1 shows the list of Logic Elements usage for 8 bit implementation. This indicates the size of the implemented circuit hardware resource. Table 1: Comparison of LEs usage in 8 bit implementation No Implementation of non restoring algorithm for 8 bit LEs 1 8 bit (with seven segment) 85 2 8 bit (without seven segment) 71 3 optimized 8 bit (with seven segment) 64 4 optimized 8 bit (without seven segment) 50 Table 2: PowerPlay Power Analyzer Status No PowerPlay Power Analyzer Status 8 bit with optimization (mW) 8 bit without optimization (mW) Low Medium Low 1 Total Thermal Power Dissipation 71.65 447.96 72.84 2 Core Dynamic Thermal Power Dissipation 0 190.47 0 3 Core Static Thermal Power Dissipation 47.36 48.06 47.36 4 I/O Thermal Power Dissipation 24.29 209.44 25.48 Conclusion: This implementation and analysis shows that proposed method is most efficient of hardware resource. This is reasonable, because it only uses subtract operation and append 01. The result shows that the proposed algorithm is easy to implement and also uses less resources. The result is extended for square root implementation of 8 bit floating point number and also it can be expanded to larger numbers to solve complicated square root problem in FPGA implementation.
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