• 한국IT서비스학회지
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• 제10권2호
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• pp.247-257
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• 2011

In this paper, we propose a multiple-disseminators determining mechanism for Efficient Code Dissemination with low-delay(ECoDi) for wireless sensor networks (WSN). Code dissemination is in the spotlight as an important research issue since sensor nodes are necessary for updating new software remotely or fixing bugs dynamically. In particular, the time factor for code dissemination is the most important factor in order that the normal operation of nodes can be continuously performed as soon as finishing the dissemination. For this factor, ECoDi determines the set of disseminators through regression analysis based on the size of distributed code and the time of past unicasts and broadcasts. Then it transmits the entire code as a unicast to multiple disseminators, and the disseminators broadcast the code to the remaining neighbor nodes. Performance results on a testbed show that ECoDi reduces dissemination time significantly compared to a conventional scheme.

• 한국측량학회지
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• 제16권1호
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• pp.95-101
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• 1998

이 논문에서는 한국경위도원점의 실용성과 및 VLBI 관측점과의 연결에 의한 국제지구기준좌표계94(ITRF94)성과의 결정과정을 설명하고 있으며 이를 이용한 원점변환요소를 도출하고 있다. 또한 실용성과와 31점으로 구성된 지구중심좌표계 KTRF94 성과간의 국가변환요소를 가중변수법을 이용하여 산정하고 결과를 제시하였다. 이 변환요소에 대한 특성을 분석한 결과, 앞으로 KTRF성과를 사용한다면 기선해석의 초기좌표 계산이나 지구중심좌표계의 3차원 성과산정에 활용될 수 있음을 보여주고 있다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.410-417
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• 2002

We consider the constraint based explicit routing problem in MPLS based IP Network. In this problem, we are given a set of traffic demands and a network with different link capacities. The problem is to assign the demand commodities to the paths in the network while minimizing the maximum link load ratio. We formulate this problem as an integer programming problem and propose an efficient column generation technique. To strengthen the formulation, we consider some valid inequalities. We also incorporate the column generation technique with variable fixing scheme Computational results show that the algorithm gives high quality solutions in a short execution time.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.89-90
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• 2019

The purpose of this study is to clarify the difference between design and construction conditions based on theory for support (S) and infill (I) distinction and separation in long-life housing, and to search for future direction. To do this, the SI theory is summarized and the construction situation is examined in the demonstration house and the differences and limitations are analyzed. In order to realize SI separation in Korea, it is necessary to set the position of pipe shafts for sewage and drainage, buried in the structure and Ondol layer of the private pipes, buried various wires in the inner wall, and fixing the position of the inner wall.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.565-580
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• 2006

Set in constant increase and period current of lively technical development of railroad use and construction of cable stayed bridge railway bridge, one of bridge form of most suitable that think side police officer and the material enemy of bridge that use long rail, is increasing laying stress on the foreign countries. Main tower fixing department of this cable stayed bridge is consisted of main tower flange that support bearing plate, bay ring plate bearing plate, support end rib and diaphragm etc, as stress transmission mechanic that tensility of cable socket into normal force of main tower, and is used this time. These structural elements is very complex the structure and direction of load delivered from socket specially calbe particularly be different, and need FEM analysis that use Thick Shell element for suitable arrangement of mutual stress flowing grasping and absence that follow hereupon because all of the each support plate angle that suport this differ.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2003년도 춘계학술발표논문집
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• pp.267-270
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• 2003

All artificial infernal organs which are using electric energy supply energy with inductive couple. Transcutaneous energy transmission system enhance survival chance of the patients and quality of life by reducing volume and mass. In this research, we used both tune in transmission system in state of fixing cycle in order to increase the voltage gain and the current gain and to reduce effect of leakage inductance. Also to maximize the effect of resonance, a constant frequency duty cycle control method is used. Test is progressed with litz wire which is set up with various sizes of core to minimize size of converter. This research aimed in analysis of transcutaneous energy transmission system and in measuring of stability and efficiency of Lithium-ion battery charge which are using transmitted energy.

• Nuclear Engineering and Technology
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• 제53권9호
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• pp.2953-2959
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• 2021

A new practical modeling of the Norton's power law creep is proposed and implemented to analyze the high temperature behaviors of Alloy 690 SG tube material. In the model, both the stress exponent n and the rate constant B are simply treated as the temperature dependent parameters. Based on the two-step optimization procedure, the temperature function of the rate constant B(T) was determined for the data set of each B value after fixing the stress exponent n value by using the prior optimized function at each temperature. This procedure could significantly reduce the numerical errors when using the power law creep equations. Based on the better description of the steady-state creep rates, the experimental rupture times could also be well predicted by using the Monkman-Grant relationship. Furthermore, the difference in tensile strengths at high temperatures could be very well estimated by assuming the imaginary creep stress related to the given strain rate after correcting the temperature effects on the elastic modulus.

• 무역상무연구
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• 제42권
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• pp.163-186
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• 2009

On April 11, 1980, the "United Nations on Contracts for the International Sale of Goods" ("CISG") was prepared by the United Nations Commission on International Trade Law (UNCITRAL) and approved by a diplomatic conference in Vienna providing uniform law for international sales of goods. It took effect as of March 1, 2005, in Korea. It is set forth on the seller's remedies for breach by the buyer Section III (Art. 61 - 65) under the CISG. In this study, the focus is only on the seller's notice fixing additional final period for performance (Art. 63) and the right to avoid the contract (Art. 64), with examination on some relevant foreign arbitral awards rendered by the ICC and the CIETAC together. Article 63 provides that the seller may fix an additional period of time for reasonable length for performance by the buyer of his obligation. It was found from the above arbitral awards that the concept of 'reasonable length' should be decided on a case-by-case basis, given the specific circumstances in the case [Art. 63(1)]. It is provided that unless the seller has received a notice that he will not perform within the period so fixed, the seller may not, during that period, resort to any remedy for breach of contract in accordance with Article 63(2). Article 64(1) provides the means and grounds for avoidance of the contract, which can be avoided 1) when the breach of the buyer amounts to a fundamental breach of contract, or 2) when the additional period of time is fixed by the seller, unless the buyer declares that he will not perform so within the period of fixed time. As we examined in the above arbitral awards, it was held that the contract is avoided when the seller sends the final notice stating that he will avoid the contract, after the expiration of the additional period of time fixed by the seller in the ICC award. On the contrary, it was held that the contract should be deemed to be avoided exactly when the expiration of additional period noted in the avoidance notice is elapsed in the CIETAC award. Article 64(2) sets time limits for avoidance.

• Investigative Magnetic Resonance Imaging
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• 제25권1호
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• pp.1-9
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• 2021

The aim of this study was to provide a new assessment of rotator cuff muscle activity. Eight male subjects (24.7 ± 3.2 years old,171.2 ± 9.8 cm tall, and weighing 63.8 ± 11.9 kg) performed the study exercises. The subjects performed 10 sets of the exercise while fixing the elbow at 90 degrees flexure and lying supine on a bed. One exercise set consisted of the subject performing external shoulder rotation 50 times using training equipment. Two imaging protocols were employed: (a) true fast imaging with steady precession (TrueFISP) at an acquisition time of 12 seconds and (b) multi-shot spin-echo echo-planar imaging (MSSE-EPI) at an acquisition time of 30 seconds for one echo. The main method of assessing rotator cuff muscle activity was functional T2 mapping using ultrafast imaging (fast-acquired muscle functional MRI [fast-mfMRI]). Fast-mfMRI enabled real-time imaging for the identification and evaluation of the degree of muscle activity induced by the exercise. Regions of interest were set at several places in the musculus subscapularis (sub), musculus supraspinatus (sup), musculus teres minor (ter), and deltoid muscle (del). We used the MR signal of the images and transverse relaxation time (T2) for comparison. Most of the TrueFISP signal was not changed by exercise and there was no significant difference from the resting values. Only the T2 in the musculus teres minor was increased after one set and the change were seen on the T2 images. Additionally, except for those after one and two sets, the changes in T2 were significant compared to those at rest (P < 0.01). We also demonstrated identify and visualize the extent to which muscles involved in muscle activity by exercise. In addition, we showed that muscle activity in a region such as a shoulder, which is susceptible to B0 inhomogeneity, could be easily detected using this technique.

• 사물인터넷융복합논문지
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• 제4권2호
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• pp.7-11
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• 2018

본 논문에서는 기구학을 이용한 이족보행 로봇의 보행패턴 생성방법을 살펴본다. 2족 보행로봇이 3차원 공간상에서 모든 동작 및 보행이 가능하기 위해 필요한 자유도는 각 다리별로 6자유도이다. 따라서 본 논문에서는 로봇의 보행을 위해 간략화된 보행로봇의 구조를 살펴보고 발목의 경로를 설정한 후 기구학을 이용하여 조인트 각도를 파악하여 생성한다. 또한 로봇의 기구 해석을 위해 한쪽 다리의 조인트들에 대해 좌표계를 설정하였다. 조인트 각도를 역기구학을 이용하면 로봇의 보행 패턴을 생성할 수 있다. 최종적으로 발목의 궤적 설정과 이를 통한 보행 패턴 생성 과정을 살펴보기로 한다.