• Journal of Distribution Research
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• v.6 no.2
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• pp.1-17
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• 2002

The recent dot-com craze has been one of the main causes that accelerated the growth of internet-related companies in diversity as well as in size. Meanwhile, the domestic market of supplies and equipment for internet businesses has been dominated by major foreign companies. To regain their market positions, the domestic manufacturers had to find the way to build up their competitive advantages, such as meeting their customers needs and reducing overall costs. In this study, one domestic PC server manufacturer, which competes fiercely with foreign manufacturers for the top place, has been chosen as a model to evaluate its current supply chain and to find an area that can be improved for a better performance. System Dynamics is used throughout the study. The central concept to system dynamics is understanding how all the objects in a system interact with one another. It focuses on feedback and secondary effects to think through how a strategy might or might not work, depending on how organizational changes are received, and what kinds of consequences emerge. Then, computerized models were built for simulations, each with different conditions, and, finally, the results were evaluated based on some criteria which are considered to be important and meaningful. The inefficiency that exists in the supply chain was proved to be a thirty-day long purchasing order leadtime, and it was expected that more effective supply chain could be formed if the leadtme were reduced to 14 days or 7 days. The results of simulations showed that the overall expected costs in supply chain was the least with the purchasing leadtime being 7 days. The lower average number of parts held as inventory, along with the reduced lost sales, acted as the factor reducing the expected overall costs. Although there was a slight increase in the average number of final products held as inventory and the total ordering cost, the benefits from lower parts inventory and reduced lost sales were large enough to justify the overall cost reduction.

• Korean Journal of Construction Engineering and Management
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• v.17 no.6
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• pp.40-52
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• 2016

In the 1960s and 1970s when Korea experienced rapid economic growth, a considerable number of buildings were constructed in the country. And since 2000, a large number of sizable and complex buildings have been being built. Specifically, as the operation and maintenance cost alone accounts for 85% of the life cycle cost of a building, efficient Facility Management (FM) is required. However, data needed in the operation and maintenance phase are not sufficiently exchangeable with data created in other phases like the planning, design and construction phases. The upper phase has higher value of data but data exchange rate is low, resulting in inefficiency. To this end, this research derived major business functions for facility management: three categories and 19 detailed functions in classification from owner's perspective. Based on the derived items, this research proposes a methodology to evaluate the 'FM Workload', 'Facility Management (FM) Data', and 'FM Data Created in Engineering and Construction Phases' thereby analyzing plans for efficient operation and maintenance. The applicability of proposed methodology was tested by examining real-world cases of public and private companies.

• The KIPS Transactions:PartA
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• v.14A no.2
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• pp.77-84
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• 2007

The intima media thickness(IMT) of the carotid artery from B mode ultrasound images has recently been proposed as the most useful index of individual atherosclerosis and can be used to predict major cardiovascular events. Ultrasonic measurements of the IMT are conventionally obtained by manually tracing interfaces between tissue layers. The drawbacks of this method are the inter and intra observer variability and its inefficiency. In this paper, we present a multiresolution snake method combined with the dynamic programming, which overcomes the various noises and sensitivity to initialization of conventional snake. First, an image pyramid is constructed using the Gaussian pyramid that maintains global edge information with smoothing in the images, and then the boundaries are automatically detected in the lowest resolution level by minimizing a cost function based on dynamic programming. The cost function includes cost terms which are representing image features and geometrical continuity of the vessel interfaces. Since the detected boundaries are selected as initial contour of the snake for the next level, this automated approach solves the problem of the initialization. Moreover, the proposed snake improves the problem of converging th the local minima by defining the external energy based on multiple image features. In this paper, our method has been validated by computing the correlation between manual and automatic measurements. This automated detection method has obtained more accurate and reproducible results than conventional edge detection by considering multiple image features.

• Fire Science and Engineering
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• v.33 no.6
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• pp.20-27
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• 2019

In this study, a new function with higher accuracy for fire heat release rate prediction was developed. The 'αt²' curve, which is the major exponential function currently used for fire engineering calculations, must be improved to minimize the prediction gap that causes fire system engineering inefficiency and lower cost-effectiveness. The newly developed prediction function was designed to cover the initial fire stage that features rapid growth based on logistic function theory, which has a more logical background and graphical similarity compared to conventional exponential function methods for 'αt²'. The new function developed in this study showed apparently higher prediction accuracy over wider range of fire growth durations. With the progress of fire growth pattern studies, the results presented herein will contribute towards more effective fire protection engineering.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.261-271
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• 2014

Construction industry becomes large and complicated as that occurred in the construction processes and operations, and the growing social demand for more systematic and efficient methods of integrated management increases. Current facility maintenance system has been regarded as large labor-intensive and fairly stagnant, and faced on several issues including inefficiency in cost and time to collect and utilize various field information. Thus, this paper presents a maintenance prototype utilizing NFC technology and smart devices to efficiently collect and manage the field information in the course of the construction processes. By choosing dam facilities as a case study, construction data for dam inspection and maintenance were classified according to dam maintenance guideline, and database structure was constructed to incorporate with the NFC tags and smart device interface. The system prototype presented in this paper would improve the quality of the dam facilities maintenance system and provide business convenience and usability by contributing increased efficiency of field information management and sharing.

• Archives of Plastic Surgery
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• v.43 no.2
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• pp.204-209
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• 2016

Temporal hollowing occurs to varying degrees after pterional craniotomy. The most common cause of temporal hollowing is a bony defect of the pterional and temporal regions due to the resection of the sphenoid ridge and temporal squama for adequate exposure without overhang. The augmentation of such bony defects is important in preventing craniofacial deformities and postoperative hollowness. Temporal cranioplasty has been performed using a range of materials, such as acrylics, porous polyethylene, bone cement, titanium, muscle flaps, and prosthetic dermis. These methods are limited by the risk of damage to adjacent tissue and infection, a prolonged preparation phase, the possibility of reabsorption, and cost inefficiency. We have developed a method of temporal augmentation using a calvarial onlay graft as a single-stage neurosurgical reconstructive operation in patients requiring craniotomy. In this report, we describe the surgical details and review our institutional outcomes. The patients were divided into pterional craniotomy and onlay graft groups. Clinical temporal hollowing was assessed using a visual analog scale (VAS). Temporal soft tissue thickness was measured on preoperative and postoperative computed tomography (CT) studies. Both the VAS and CT-based assessments were compared between the groups. Our review indicated that the use of an onlay graft was associated with a lower VAS score and left-right discrepancy in the temporal contour than were observed in patients undergoing pterional craniotomy without an onlay graft.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.2
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• pp.43-51
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• 1993

It is very important entity that a map of urban facility is in civic life and development of city. But now, there are many needs of computerization which was used for management of urban facility map because inefficiency was produced due to management of urban facility map by hand. This paper, it was showed that a processing of establishing database in computer by applying GIS. The used sample area in studying in Ansan city in Kyunggi province and a sewer pipe which was in there adapted to establish database in computer. A map of administration district, which is 1:38,000, a map of complex urban planning of city, which is 1:3,000, and the facility map were used for the input of spatial data and the address, the year when sewer pipe was burried, and the quality of pipe, the pipe diameter, and the length of pipe were used as attribute data. Relational structure was used for establishment of database then, searching, analyzing, and processing were possible. Additionary, the result of this studying can be used for replacement of a old sewer pipe, a material quantity which is related with repairement of sewer pipe, and calculation of time, cost by application program framed by Fortran.

• KIISE Transactions on Computing Practices
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• v.22 no.6
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• pp.268-277
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• 2016

IoT (Internet of Things) technologies have largely contributed to our smart living environment. The smart parking system is one of the prominent services that IoT supports. To identify the parked vehicles, the previous parking system use special identifying devices, the RFID tags carried by the users, and the high quality camera to recognize the vehicle license numbers. However, the previous methods cause cost inefficiency and unfriendly usages. To address these problems, we propose a smart parking system based on ultrasonic sensors and Bluetooth communication. The proposed system decides the available slots by using the sensor motes located in the parking spaces. Also it recognizes the location of the parked vehicle using Bluetooth RSSI between a Smartphone and the sensor motes. In addition, based on these converging technologies, it can support the parked routes of vehicles for users. To evaluate the implemented smart parking system, we applied the RSSI transform equations and the recognition rate for parked vehicles. As a result, the accurate rate of transformed distances could be measured.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3534-3547
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• 2014

Although there are many positive sides of the current fee-for-service payment schedule, there is a strong necessity to control the rapidly increasing national healthcare expenditure. The global budget is often mentioned as one prominent alternative for solutions. In this article, both microscopic and macroscopic approaches are considered to set the hospital medical expenditure budget. In a macroscopic aspect, the SGR model, which considers the financial limit of the healthcare system, is used to set the next year target budget. In addition, the DEA model is used to measure the inefficiency and cost recognition. In this article, the national medical target expenditure is distributed to an individual hospital based on the level of efficiency. By combining the SGR and DEA, it will be possible to set a real world applicable target medical expenditure budget model.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.8
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• pp.351-360
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• 2016

Sensors equipped in Internet-of-Thing (IoT) devices are used to measure the surrounding contexts, and IoT applications analyze the contexts to infer situations and provide situation-specific smart services. There are different context acquisition schemes including pulling, pushing, and broadcasting. Most IoT devices support only one of the schemes. Hence, there can be an incompatible issue on data acquisition schemes between applications and devices, and consequently it could result in an increased development cost and inefficiency on application maintenance. This paper presents design patterns which can effectively remedy the incompatibility problem. By applying the patterns, IoT applications with incompatibility can be systematically and effectively developed. And, also its maintainability is expected to increase.