• 대한관절경학회지
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• 제2권1호
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• pp.45-50
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• 1998

Recently, a variety of arthroscopic techniques have been reported for the treatment of the displaced tibial eminence fracture. The purpose of this study was to describe details of arthroscopic technique using pull-out wire and to evaluate the results. Eleven patients with irreducible type II and type III tibial eminence fractures underwent the arthroscopic reduction and internal fixation using double strand pull-out wiring. The anterior cruciate ligament tibial drill guide was utilized for the reduction of fracture and passage of the guide pins. The tibial eminence fracture was firmly fixed with double strand 26-gauge pull-out wire(0.45mm diameter). Fracture union was achieved at 7.2 weeks (range, six to eight weeks) after operation. All cases were united at the last follow-up. Subjectively, nine patients had no pain and no restriction of daily activities. Two patients with combined injuries had limitation of knee motion(10 to 130 degrees, respectively) and one patient showed mild anterior laxity. Early rehabilitation was enabled without loss of reduction and breakage of pull-out wire. The arthroscopic reduction and internal fixation using pull-out wire showed good results including early rehabilitation, early fracture union, minimal morbidity, and no requirement of the second operation for hard ware removal.

• Transactions on Electrical and Electronic Materials
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• 제17권2호
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• pp.57-68
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• 2016

In this study, we present the modern hybrid system based power generation for electric vehicle applications. We describe the hybrid structure of modified current source based DC - DC converters used to extract the maximum power from Photovoltaic (PV) and Fuel Cell system. Due to reduced dc-link capacitor requirement and higher reliability, the current source inverters (CSI) better compared to the voltage source based inverter. The novel control strategy includes Distributed Maximum Power Point Tracking (DMPPT) for photovoltaic (PV) and fuel cell power generation system. The proposed DC - DC converters have been analyzed in both buck and boost mode of operation under duty cycle 0.5>d, 0.5<d<1 and 0.5<d for capable electric vehicle applications. The proposed topology benefits include one common DC-AC inverter that interposes the generated power to supply the charge for the sharing of load in a system of hybrid supply with photovoltaic panels and fuel cell PEM. An improved control of Direct Torque and Flux Control (DTFC) based induction motor fed by current source converters for electric vehicle.In order to achieve better performance in terms of speed, power and miles per gallon for the expert, to accepting high regenerative braking current as well as persistent high dynamics driving performance is required. A simulation model for the hybrid power generation system based electric vehicle has been developed by using MATLAB/Simulink. The Direct Torque and Flux Control (DTFC) is planned using Xilinx ISE software tool in addition to a Modelsim 6.3 software tool that is used for simulation purposes. The FPGA based pulse generation is used to control the induction motor for electric vehicle applications. FPGA has been implemented, in order to verify the minimal error between the simulation results of MATLAB/Simulink and experimental results.

• 대한안전경영과학회지
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• 제10권3호
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• pp.89-98
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• 2008

A preventive maintenance model, caller FNBM($\alpha$, $\delta$, $\gamma$)model, is proposed to decide an optimal repair number under achieved availability requirements(r) along with taking two types of failures (repairable or irrepairable) into account. In this model, the current system is replaced by a new one in case when it doesn't meet the achieved availability requirement, even though it is repairable failure; Otherwise it is replaced in time of the first irrepairable failure. Assumed that the j-th failure is repairable with probability ${\alpha}_j$ minimal repairs are allowed for repairable failure between replacements. Expected cost rate for preventive maintenance model is developed using NHPP(Non-Homogeneous Poisson Process) in order to determine the optimal number $n^*$, also numerical examples are shown in order to explain the proposed model. Since the proposed FNBM($\alpha$, $\delta$, $\gamma$)model includes Park FNBM model(1979) and Nakagawa FNBM(p)model(1983) this proposed model is thought to be better than previous model, especially for weapon system which requires availability as primary parameter.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.401-412
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• 2000

Like other livestock, monogastric animals are essential components of the farming systems in the tropical countries. Pigs, chicken and ducks are by far the most important animals in the culture of the peoples of developing countries in the tropics. Traditionally these animals are raised in small farms and they are also the bulk producers of meat, eggs etc. in the tropics. In many countries the farmers of these small farms are unable to meet the requirement set by financial institution and other loan giving agencies for agricultural loan. Thus, the small farmers can get neither the opportunity to generate sufficient income to support the family nor to extend the livestock activities. The production systems are characterized by small number of animals with no or minimal inputs, low outputs and periodic destruction of animals by disease. Typically the litter size or flocks are small in number with each household containing 5-6 pigs and 7-10 poultry. Animals are owned by individual households and mostly maintained under a scavenging systems with little or no inputs for housing, feeding or health care. Because of the nature of this production system, productivity of these animals is rather low. The low level of inputs is due to a lack of capital and a low risk oriented outlook. The feed resource base for monogastric is scavenging and consists of household waste, roots and tuber, grain by-products and anything edible found in the immediate environment. Usually farmers select breeding gilts from their own female piglets or to a lesser extent, buy them from neighbors for natural mating. As regards poultry attempts have been made to increase egg and meat production by improving local poultry birds by upgrading and crossbreeding with exotic germ plasma in the tropics. Animal disease present a major constraint to animal production in the tropical region and the extent of the losses due to disease is very high.

• 한국항행학회논문지
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• 제16권1호
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• pp.96-102
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• 2012

모바일 인터넷 시스템의 목표는 고속 데이터 율, 낮은 지연 그리고 유연한 대역폭 진화를 제공할 수 있는 최적화된 패킷 무선접속기술을 제공하는 것이다. 따라서 연속적인 이동성과 서비스 품질 그리고 최소지연을 갖는 패킷 스위치 트래픽 목표를 제공하는 LTE 네트워크 구조가 설계되었다. LTE 시스템에서의 중요한 요구조건은 셀 경계에서의 BER 성능과 데이터 처리율을 개선하는 것이다. 이것은 통신 지역에서 지리적 영역과 데이터 처리율 측면에서 서비스의 일관성을 제공한다. 하지만 셀룰러 시스템에서 셀의 중앙과 경계지역 사용자 사이의 SINR 차이는 20 [dB] 정도가 된다. 이러한 차이는 통신 영역이 제한된 셀룰러 시스템에서 더욱 크다. 이 현상은 셀 중앙의 사용자에 비하여 셀 경계의 사용자에게 대단히 낮은 데이터 처리율 유발하고 큰 QoS 차이를 발생시킨다. 본 논문에서 인접 셀 간섭을 감소하기 위한 분석적인 방법을 제시하고 모바일 인터넷 환경에서 OFDM 시스템 파라미터에 따른 SIR 및 BER 성능을 보였다.

• Journal of Nutrition and Health
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• 제37권5호
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• pp.394-405
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• 2004

The objective of this study is to develop a nutrition policy on food and nutrition labeling and education systems for fast food and carbonated soft drinks in Korea by identifying the fast food and soft drink use and by examining nutrition policies and labeling in Korea and other countries. Fast food is defined as food dispensed quickly at a restaurant generally offering a limited menu of inexpensive items, which may be mostly not nutritious. It is a growing component of the Korean diet, especially on children and adolescent population. Low nutrient dense beverages such as carbonated drinks are also increasing in the children and adolescent's diet in Korea and concern has been raised that these beverages may replace more nutritious beverage and provide empty calories. According to 2001 Korean national health and nutrition survey, fast food and carbonated soft drinks were most popular among 13 - 19 years old adolescents. Thirty six and 72 percent of adolescents consumed hamburger and carbonated beverage equal to or more than once a week, respectively. In United States, all processed food including soft drinks should disclose full nutrition information by nutrition labeling requirement.. Restaurant foods are not required to provide nutrition information currently, but legislation on mandatory nutrition labeling of fast foods with other restaurant foods has been proposed currently in US. The sales of foods of minimal nutritional value, such as soft drinks, in the nation's schools is regulated by the United States Department of Agriculture. Nutrition information about fast food in US has been provided by fast food companies, non-profit organizations, hospitals and government through internet, booklet and brochure, etc, but the information is available from only a few resources in Korea. This study suggests a nutrition policy on fast food and soft drink use which includes establishing mandatory nutrition labeling and developing nutrition education materials and programs by web-site, booklet and government and school programs in Korea.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권4호
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• pp.327-333
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• 2006

Future cell-based therapies such as tissue engineering will benefit from a source of autogenous pluripotent stem cells. There are embryonic stem cells (ESC) and autologous adult stem cells, two general types of stem cells potentilally useful for these applications. But practical use of ESC is limited due to potential problems of cell regulation and ethical considerations. To get bone marrow stem cells is relatively burden to patients because of pain, anesthesia requirement. The ideal stem cells are required of such as the following advantages: easy to obtain, minimal patient discomfort and a capability of yielding enough cell numbers. Adipose autologus tissue taken from intraoral fatty pad or abdomen may represent such a source. Our study designed to demonstrate the ability of human adipose tissue-derived stromal cells (hATSC) from human abdominal adipose tissue diffentiating into osteocyte and adipocyte under culture in vitro conditions. As a result of experiment, we identified stromal cell derived adipose tissue has the multilineage potentiality under appropriate culture conditions. And the adipose stromal cells expressed several mesenchymal stem cell related antigen (CD29, CD44) reactions. Secondary, we compared the culture results of a group of hATSC stimulated with TGF-${\beta}$1, bFGF with a hATSC group without growth factors to confirm whether cytokines have a important role of the proliferation in osteogenic differentiation. The role of cytokines such as TGF-${\beta}$1, bFGF increased hATSC's osteogenic differentiation especially when TGF-${\beta}$1 and bFGF were used together. These results suggest that adipose stromal cells with growth factors could be efficiently available for cell-based bone regeneration.

• International Journal of Advanced Culture Technology
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• 제7권4호
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• pp.208-221
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• 2019

The inference for this research was concentrated on client's data protection in cloud computing i.e. data storages protection problems and how to limit unauthenticated access to info by developing access control model then accessible preparations were introduce after that an access control model was recommend. Cloud computing might refer as technology base on internet, having share, adaptable authority that might be utilized as organization by clients. Compositely cloud computing is software's and hardware's are conveying by internet as a service. It is a remarkable technology get well known because of minimal efforts, adaptability and versatility according to client's necessity. Regardless its prevalence large administration, propositions are reluctant to proceed onward cloud computing because of protection problems, particularly client's info protection. Management have communicated worries overs info protection as their classified and delicate info should be put away by specialist management at any areas all around. Several access models were accessible, yet those models do not satisfy the protection obligations as per services producers and cloud is always under assaults of hackers and data integrity, accessibility and protection were traded off. This research presented a model keep in aspect the requirement of services producers that upgrading the info protection in items of integrity, accessibility and security. The developed model helped the reluctant clients to effectively choosing to move on cloud while considerate the uncertainty related with cloud computing.

• 한국정보기술학회논문지
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• 제17권6호
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• pp.9-16
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• 2019

최근 제조 공정을 개선하려는 기업들은 스마트 팩토리를 도입, 이에 따른 도약이 특별히 눈에 띈다. 이는 최소한의 수동 제어를 통해 완벽하게 생산시설의 프로세스를 수행하는 스마트 팩토리의 영역을 최대화하고 추론의 오차를 최소화 하는 것이 최종 목적이다. 본 연구는 무인 생산, 관리, 포장, 배송 관리를 위한 프로젝트의 일부로써 무인생산의 자동화 설비의 철근 추적을 통해 롤러의 자동 교정을 수행하기 위해 철근 추적 시작점 검출에 대한 연구이며, 시작지점부터 끝점까지의 위치를 정확히 추적해야 하는 요구사항을 만족해야 한다. 추적성능을 높이기 위해서는 시작점 설정이 주요한데 기존의 시간 기반 검출방법을 통해서는 조도, 분진 등 환경에 따라 추적오류의 발생 확률이 높다. 본 논문에서는 환경에 따른 오차를 줄이기 위해 고속 IR카메라의 평균 밝기 변화를 이용한 시작점 검출 방법을 제안하며, 제안 사항을 통해 15%이상의 성능 향상을 확인하였다.

• 한국정밀공학회지
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• 제13권9호
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• pp.114-129
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• 1996

This paper describes the whole development phase for the underwater vehicle actuating system with high hydroload torque disturbance. This includes requirement analysis, system modeling, control algorithm design, real time implementation, test and performance evaluations. As for driving control algorithms, fuzzy logic, variable structure and PD(Proportional-Differential) algorithm were designed and implemented on board controller using a single chip microprocessor. Intel 8797. And test and performance evaluation is carried out both single test and wystem integration test. We could confirm the basic performance of actuating system through the single test and gereral developing work of any actuating systems was finished with a single performance test of actuating system without system integration test. But, we suggested that system integration test be needed. System integration test is carried out using G/C HILS(Guidance and Control Hardware-In-the -Loop Simulation) which is constituted flight motion simulator, load simulator, real time host computer and the related subsystems such as inertial navigation system, power supply system and Guidance and Control Computer etc.. The most important practical contribution of this paper is that full system characteristics such as minimal control effort, enhancement of guidance and autopilot performance by the actuating system using G/C HILS technique are investigated. Through full running G/C HILS, in spite of the passing to single tests, some control algorithm resulted in failure as to stability of full system and system time frame.