• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.1D
• /
• pp.67-72
• /
• 2008

Heavy equipment is a very important factor for successful construction implementation. Also, the cost for heavy equipment is a major part of construction cost. Therefore, the estimation of equipment cost is a critical job in the construction planning phase. A formula for production rates shown in 'Standard Unit Labor' has been used to estimate construction equipment capability per hour and cost. Although the performance of equipment has been improved, the efficiency rates in the formula are not updated lately. Therefore, this research performed several site visits to measure construction equipment working time and then calculates the efficiency rates for hydraulic backhoe, loader, and dump truck. The results show that the measured efficiencies of backhoe and loader are higher than current ones and vice versa for dump truck. This research proposes the needs for a standardized calculation formula and systematic and long-term data collection and measurement for updating efficiency rates for heavy equipment.

• International conference on construction engineering and project management
• /
• 2013.01a
• /
• pp.226-230
• /
• 2013

In the tall building construction, the slab formwork largely impacts on construction cost. Because productivity of a slab formwork is influenced by a number of and the efficiency of equipment, using the equipment-based construction method, an appropriate equipment input planning is crucial for the productivity. Meanwhile, the general equipment input planning is conducted by intuition based on experience due to the lack of equipment productivity data. Thus, this study develop a simulation model to analyze table formwork productivity and to propose an optimum equipment input plan that reflects the construction process, based on the full consideration of the economic factors. This study developed a simulation model by using CYCLONE and the data for the model was collected by measuring the duration of each unit activity in the tall building where table forms were applied. It is expected that a simulation model helps users to make better decision on the equipment input planning of slab formwork.

• Journal of the Korea Institute of Building Construction
• /
• v.8 no.1
• /
• pp.37-42
• /
• 2008

As use of construction equipment has been increasing continuingly, the proportion of equipment expense to the total construction cost has become higher. However, there is a difference between the equipment expenses section in 'Poom-Sam' and practical data, because 'Poom-sam' does not consider non-working days due to weather conditions, legal holidays and management conditions. Therefore, 'Poom-Sam' does not present a reasonable standard for estimating construction equipment expenses. In this study, to estimate realistic construction equipment operating hours, firstly, construction equipment was classified according to work, and weather conditions, in which each work could not be executed, were established. Then, weather data on Seoul and Busan($2004{\sim}2006$) and legal holidays were analyzed to suggest annual standard operating hours. The annual standard operating hours of earthmoving & excavating, compaction, and drilling equipment was estimated to be 1,430 hours, and lifting equipment, concrete paving equipment, asphalt paving equipment, concrete equipment, and crushing & conveying equipment were estimated to be 2,124 hours, 1,156hours, 1,188hours, 1,688hours, and 2,152hours respectively.

• Journal of the Korea Safety Management & Science
• /
• v.9 no.4
• /
• pp.121-127
• /
• 2007

CSP(Concurrent Spare Parts) is supplied with the procurement of new equipment or weapon system and is used to sustain the equipment without resupply during the initial coverage period. This study is concerned with a problem of determining the near optimal inventory level of the spare parts, especially Concurrent Spare Parts. For this, we utilize the mixed periodic and continuous review polices considering the CSP and (r,Q) Policies concurrently in a two-echelon distribution system. We propose the mathematical model to minimize the total cost which is composed with ordering cost, purchasing cost, holding cost, and stickout cost. If the mixed policy is compared to other policies(CSP, (r,Q)), the proposed methodology performs well and is best policy in the equipment maintenance expenses.

• International conference on construction engineering and project management
• /
• 2013.01a
• /
• pp.219-225
• /
• 2013

State transportation agencies utilize fleets of heavy equipment to construct and maintain roadways. Equipment cost models can be developed to forecast economic life, which is the point at which the average unit cost to date reaches a minimum. A calculated economic life and cost models can be used to quantify the impacts of management strategies applied to a fleet. The purpose of this research was to develop an accurate method of quantifying the results of management strategies applied to a fleet of heavy construction equipment. The strategies evaluated are related to the annual usage of the fleet and the size of the fleet. More specifically the methodology is used to adjust the economic model to consider a limit to the annual decline in machine usage and a reduction in the number of machines in the fleet. When limiting annual machine usage, a specified rate is applied to the usage of the fleet, while total usage is held constant. This causes aging at a modified rate. A reduction in fleet size also causes a change to the usage of a fleet as the fleet must use fewer machines to produce the same total usage.

• Korea Journal of Hospital Management
• /
• v.14 no.3
• /
• pp.23-48
• /
• 2009

The purpose of this study was to provide criteria which help executives to make decisions through the analysis of profitability of ultrasonography conducted in each medical department. In order to achieve such purpose, the study conducted break-even analyses on three medical departments of a university hospital in which has used ultrasonography was largely conducted in diagnosing diseases and performing surgeries. The research was carried out from January to June 2008. The data necessary for calculating cost, were collected using by computerized data. The results of the study were summarized as follows. 1. The Cost structure of each medical department: The Cost of ultrasonography was divided into direct cost and indirect cost through the categorization by cost object. Labor cost accounted for the largest portion of the direct cost with 69.3% in the department of obstetrics and gynecology, 67.4% in the department of radiology and 58.2% in the cardiac ultrasonography center, which followed by the depreciation cost of ultrasonography equipment. The calculation of the average material cost of each ultrasonographic test by medical test found that the cardiac ultrasonography center took first place with 2,355 won, followed by the department of obstetrics and gynecology with 266 won and the department of radiology with 233 won. As for the power cost of ultrasonography equipment, the department of radiology took fist place with 442,000 won. The power cost, however, did not affect much the cost price, because it accounted for only a small portion of the cost. As for indirect cost, the cardiac ultrasonography center ranked first with 7,156,000 won. Building depreciation cost accounted for the largest portion of the indirect cost. 2. Break-even analysis: Under the supposition that cost price can be divided into fixed cost and variable cost, a break-even analysis was conducted using the cost price confirmed through the cost structure of each medical department. As for the average customary charge of ultrasonography test conducted in each medical department, the department of obstetrics and gynecology charged 24,627 won, the department of radiology 53,179 won and the cardiac ultrasonography center 65,174 won. According to these results, the charges of ultrasonography test imposed by the department of radiology and the cardiac ultrasonography center wre enough to surpass break-even levels, but the charge imposed by the department of obstetrics and gynecology was not enough to offset the cost price. In conclusion, labor cost accounted for the largest proportion of cost price of ultrasonography test conducted in diagnosing diseases and performing surgeries in medical departments, followed by the fixed cost of ultrasonographic equipment depreciation cost. In medical department where the current charge of ultrasonography test turned out not to offset cost price through the break-even analysis of ultrasonographic equipment, ways to reduce fixed cost which accounts for the largest proportion of the cost price should be sought. Even medical departments whose current charge of ultrasonography test is enough to surpass break-even level are required to work for efficient management and cost reduction to continuously generate profits.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.25 no.3
• /
• pp.68-73
• /
• 2017

In this study, we design a low-cost test equipment for real-time image observation and transmission/reception distance test using 1m by 1.5m bang-pai kite. The image observation is made by using two servo motors to enable the camera to control the two axis attitude. The image observation equipment is hung on the string of a kite and the test is performed to observe the real time image. The transmission and reception distance test of the wireless RF transceiver module is conducted on the ground and in the air.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.742-743
• /
• 2007

A maintenance plan of power system equipment reduces failure rate caused by equipment's age. To prevent unexpected failure, the maintenance is performed periodically according to the interval time. The more expansive equipment's scale is, the more the maintenance without considering costs sustains a economical loss. Hence, the maintenance's time and the cost must be considered when maintenance which is considering the reliability is implemented. In this paper, optimum maintenance interval is calculated by considering minimum maintenance cost of the equipment with the combined cycle units in Korea power systems.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.58 no.4
• /
• pp.410-415
• /
• 2009

With the implementation of electric power industry reform, the utilities are looking for effective ways to improve the economic efficiency. One area in particular, the equipment maintenance, is being scrutinized for reducing costs while keeping a reasonable level of the reliability in the overall system. Here the conventional RCM requires the tradeoff between the upfront maintenance costs and the potential costs of losing loads. In this paper we describe the issues related to applying so-called the "Reliability-centered Maintenance" (RCM) method in managing electric power distribution equipment. The RCM method is especially useful as it explicitly incorporates the cost-tradeoff of interest, i.e. the upfront maintenance costs and the potential interruption costs, in determining which equipment to be maintained and how often. In comparison, the "Time-based Maintenance" (TBM) method, the traditional method widely used, only takes the lifetime of equipment into consideration. In this paper, the modified Markov model for maintenance is developed. First, the existing Markov model for maintenance is explained and analyzed about transformer and circuit breaker, so on. Second, developed model is introduced and described. This model has two different points compared with existing model: TVFR and nonlinear customer interruption cost (CIC). That is, normal stage at the middle of bathtub curve has not CFR but the gradual increasing failure rate and the unit cost of CIC is increasing as the interruption time is increasing. The results of case studies represent the optimal maintenance interval to maintain the equipment with minimum costs. A numerical example is presented for illustration purposes.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.10
• /
• pp.153-162
• /
• 2017

Weapon systems have been developed with high technology electronic equipment due to technology growth. In addition, the capital, operational and maintenance costs of weapon systems have all increased. However, cost of operation and maintenance for weapon systems has been decreased relatively compared to the increased capital cost of weapon systems. Therefore, the defense industry needs to research the life cycle cost of weapon systems that have high operational and maintenance costs. This paper focuses on maintenance equipment for the operation and maintenance of weapon systems. Recently, it seems that the weapon systems that have periodic calibration with maintenance equipment are valid. The equipment requires periodic calibration by the manufacturer to check its own validation. Basically, customers demand high reliability devices from foreign companies that have qualified in the global market. Therefore, the tools need to be calibrated overseas. In other words, weapon systems are not available when the equipment has to be calibrated overseas because the systems require validation with valid maintenance equipment. A purpose of this paper is to compare the loss costs that arise from the calibration of the equipment overseas and the purchasing cost of the tools. Finally, the research shows the number of equipment that customers need to minimize the cost. This research will help to improve the efficiency of operation of weapon systems and solve the problems associated with the need for maintenance overseas.