• Journal of the Korean Society for Precision Engineering
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• v.31 no.7
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• pp.561-567
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• 2014

Precision injection mold is an essential element in order to manufacture small and precision plastic lenses used for phone camera. There are many critical factors to meet the requested specifications of high quality plastic lenses. One of the main issues to realize high quality is minimizing decenter value, which becomes more critical as pixel numbers increases. This study suggests the method to minimize decenter value by modifying ejecting structure of the mold. Decenter value of injection-molded lens decreased to 1 ${\mu}m$ level from 5 ${\mu}m$ by applying suggested ejecting method. Also, we also developed BIS (Built-in Sensor) based smart mold system, which has pressure and temperature sensors inside of the mold. Pressure and temperature profiles from cavities are obtained and can be used for deduction of optimal injection molding condition, filling imbalance evaluation, status monitoring of injection molding and prediction of lens quality.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1035-1038
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• 2005

This paper describes the designs and the implementations of two H/W IPSec Systems, look-aside and inline, on TOE (Transport Offloading Engine). These systems aim for guaranteeing the security of datagram networks while preserving the bandwidth of gigabit networks. The TOE offloads a host CPU from network burdens, so that it makes the gigabit wire speed possible, and then deeper level security architecture of the IPSec guarantees the security of gigabit service network dominated by datagram packets. The focus of this paper is to minimize the TOE's performance degradation caused by the computation-oriented IPSec. The look-aside IPSec system provides a significant improvement in the CPU offload of the IPSec cryptography loads. However, the inline system completely offloads the host CPU from whole IPSec loads, providing significant additional cost saving compared to the look-aside system. In this paper, the implementations of TOE cards including commercial IPSec processors are presented. As the result of performance evaluation with the protocol analyzer, we can get the fact that the inline IPSec system is 8 times faster than the S/W system and 2 times faster than the look-aside system.

• Korean Journal of Adult Nursing
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• v.14 no.1
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• pp.53-61
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• 2002

Purpose: This descriptive study was designed to investigate Body Mass Index(BMI), weight control behavior, and self-esteem in high school adolescents. Method: The convenience sample consisted of 129 high school females and 106 high school males. Data were collected using a self-report questionnaire from November to December, 1999. BMI was calculated by using the subject's self-reported body weight and height to identify objective obesity. Self evaluation about subjective obesity was measured by a single item question. Preferred BMI was calculated by using the subject's elf-reported body weight and height which the subjects desired. The Rosenberg's Self-Esteem Scale was utilized to measure the level of self-esteem. Results: Results of the study revealed that high school females perceived themselves as more more obese than their the actual BMI, excessively participated in dieting behavior and exercises, and reported lower self-esteem than that of males. Conclusion: Based on this study, health care providers need to educate female adolescents about healthy behavior as well as the normal weight range in BMI.

• Spatial Information Research
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• v.2 no.1
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• pp.39-46
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• 1994

GIS technique was applied to identify the geotechnical characte¬ristic of subsurface in a study area, and has produced a Geotechnical Esti¬mat ion Index(GEI) map. Groundwater level, soi I depth & weathered zone, and engineering properties of soils & rocks, were incorporated in the map through GIS. EGIS(Environmental Geologic Information System), developed by ARC/INFO GIS system, was used for this work. Environmental geologic database by EGIS was verified to be effective in analysis of engineering geological properties of the subsurface. Quantitative analysis of environmental and geotechnical information enable to develop a scoring system of GEI model, which was developed through evaluation of each goelogical factor with respect to the other factors.

• Journal of Biomedical Engineering Research
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• v.28 no.6
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• pp.713-720
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• 2007

In image-guided surgery, automatic bone segmentation of Computed Tomography (CT) images is an important but challenging step. Previous attempts include intensity-, edge-, region-, and deformable curve-based approaches [1], but none claims fully satisfactory performance. Although active contour (AC) techniques possess many excellent characteristics, their applications in CT image segmentation have not worthily exploited yet. In this study, we have evaluated the automaticity and performance of the model of Chan-Vese Multiphase AC Without Edges towards knee bone segmentation from CT images. This model is suitable because it is initialization-insensitive and topology-adaptive. Its segmentation results have been qualitatively compared with those from four other widely used AC models: namely Gradient Vector Flow (GVF) AC, Geometric AC, Geodesic AC, and GVF Fast Geometric AC. To quantitatively evaluate its performance, the results from a commercial software and a medical expert have been used. The evaluation results show that the Chan-Vese model provides superior performance with least user interaction, proving its suitability for automatic bone segmentation from CT images.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.2
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• pp.148-156
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• 2003

This paper describes the RF performance issues of UE for W-CDMA system based on 3 GPP specifications. The parameters of transmitter and receiver are derived from the viewpoint of RF performance. In order for UE to achieve high performance, the transceiver performance requirements such as ACLR, EVM, Peak Code Domain Error, spectrum emission mask, frequency error stability and TX power control dynamic range for transmitter and reference sensitivity level, blocking characteristics, noise figure, ACS, AGC dynamic range for receiver are considered. On the basis of the required parameters, the UE RF transceiver is implemented and then the evaluation of RF performance is accomplished through practical test scenarios.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.73-73
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• 2003

Purpose: To determine the motor cortex dysfunction in hemiparetic patients due to deep intracerebral hematoma, authors performed proton magnetic resonance spectroscopy (lH MRS) for the evaluation of biochemical changes in the cortex on affected hemisphere according to axonal injury at the level of internal capsule. Methods: Ten control subjects and 14 patients with documentable hemiparesis of varying severity hemiparesis were included. All the hemiparesis was caused by deep intracerebral hematoma (putaminal and thalamic hemorrhage). In vivo 1H MRS study was performed on a 3T MRI/MRS system using STEAM sequence. As a single-voxel technique, Spectral parameters were: 20 ms TE, 2000 ms TR, 128 averages, 2500 Hz spectral width, and 2048 data points. Results: We found that the mean N-acetylaspartate (NAA)/phosphocreatine (Cr) and NAA/choline (Cho) ratios were significantly decreased in the motor cortex of the hemiparesis patients compared with control subjects. Conclusions: 1H MRS examinations of the motor cortex might help to differentiate distinct clinical entities of hemiparesis and to monitor pharmacological effects in therapeutic trials, providing a quantitative biological marker for motor neuron dysfunction. Acknowledgement: This study was supported by a grant of the Center for Functional and Metabolic Imaging Technology, Ministry of Health & Welfare, Republic of Korea. (02-PJ3-PG6-EV07-000).

• Journal of Animal Environmental Science
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• v.21 no.1
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• pp.29-34
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• 2015

This study was conducted to determine the amount of manure production from Holstein dairy cattle raised in bedded pack barn and the appropriate bedding material removal time. Total six heads of dairy cows (about 715 kg weight) were raised in three pens (two heads per pen) for 62 days. Average daily production of manure containing sawdust bedding was 21.2 kg per head and that of manure excluding bedding was 18.7 kg. Moisture content of bedding materials were significantly increased up to 86% of water holding capacity (WHC) of sawdust during the first 30 days. It kept very stable level after 30 to 50 days. Theoretically, 30 days after adding fresh bedding seems to be proper removal time only based on WHC. On the other hand, from a practical perspective, maximum 50 days after adding new bedding would be fine by comprehensively considering various factors such as bedding material purchasing cost, feeding environment and manure treatment.

• Journal of Korean Society of Rural Planning
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• v.16 no.3
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• pp.117-129
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• 2010

The purpose of this paper is to develop a web-based information system for rural settlement environment diagnosis which is useful to apply the village based evaluation for new rural development projects. To achieve this purpose, this study performed : 1) analyzing the business process in the field of rural settlement environment diagnosis, 2) designing the data flow diagram and the database based on settlement environment diagnostic indices(SEDI), and 3) developing the system using APM (Apache, PHP, and MySQL) of web-system development environment. The developed system was applied to the study rural villages for testing of efficient and logical working. Users of the system, such as, researchers, decision makers, and rural residents, can input directly the village data to diagnose through a file format of Excel in MS Office. Futhermore, they can analyze the visual results with graphic and graph types, simultaneously. From the results of this study, it showed that the developed system enables decision-makers not only to assist the planning process of the rural village development project, but also to improve the level of information technology in the research and planning field concerning with rural development.

• Journal of Satellite, Information and Communications
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• v.6 no.1
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• pp.6-11
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• 2011

In this paper presents a new approach to evaluate reliability indices of electric distribution systems using genetic Algorithm (GA). The use of reliability evaluation is an important aspect of distribution system planning and operation to adjust the reliability level of each area. In this paper, the reliability model is based on the optimal load transferring problem to minimize load generated load point outage in each sub-section. This approach is one of the most difficult procedures and become combination problems. A new approach using GA was developed for this problem. GA is a general purpose optimization technique based on principles inspired from the biological evolution using metaphors of mechanisms such as natural selection, genetic recombination and survival of the fittest. Test results for the model system with 24 nodes 29 branches are reported in the paper.