• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.4
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• pp.629-637
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• 2006

Currently the research on input-queued ATM switches is one of the most active research fields. Many achievements have been made in the research on scheduling algorithms for input-queued ATM switches and also applied in commerce. The scheduling algorithms have the characteristics of improving throughput, satisfying QoS requirements and providing service fairly. In this paper, we studied on an implementation of scheduler which arbirates the input-queued ATM switches efficiently and swiftly. The proposed scheduler approximately provides 100% throughput for scheduling. The proposed algorithm completes the arbitration for N-port VOQ switch with 4-iterative matching. Also the proposed algorithm has a merit for implementing the scheduling algorithm with 1/2 area compared to that of iSLIP scheduling algorithm which is widely used. The performance of the proposed scheduling algorithm is superior to that of iSLIP in 4-iterative matching. The proposed scheduling algorithm was implemented in FPGA and verified on board-level.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1A
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• pp.122-131
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• 2000

In this paper, we propose a cell scheduling algorithm for input queueing ATM switch. The input queueing architecture is attractive for building an ultra-high speed ATM (Asynchronous Transfer Mode) switch. We proposea WMUCS (Weighted Matrix Unit Cell Scheduler) based on the MUCS which resolves HOL blocking and outputport contention. The MUCS algorithm selects an optimal set of entries as winning cells from traffic matrix (weightmatrix). Our WMUCS differs from the MUCS in generating weight matrices. This change solves the starvationproblem and it reduces the cell loss variance. The performance of the proposed algorithm is evaluated by thesimulation program written in C++. The simulation results show that the maximum throughput, the average celldelay, and the cell loss rate are significantly improved. We can see that the performance of WMUCS is excellentand the cost-effective implementation of the ATM switch using proposed cell scheduling algorithm.

• Journal of Society of Occupational Therapy for the Aged and Dementia
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• v.12 no.2
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• pp.87-95
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• 2018

Objective : Vibration stimulators are easier to obtain in clinical settings than other treatment tools, and it is advantageous that the arm activation training can be performed passively. Despite the following advantages, recent studies on vibration sense have not been activated yet. The purpose of this study was to investigate the effect of vibration sensation on the hands of the affected upper limb on unilateral reduction of stroke patients. Method : Patients with unilateral neglect due to stroke were enrolled in this study for about 3 weeks from October 19, 2018 to November 7, The research design used ABA design among the single-subject experimental research design, and a total of 18 circuits (4 baseline, 6 intervention, 3 baseline regression) were performed once a day on weekdays Respectively. MMES-K was used to select the subjects. Line bisection test (LBT), Albert's test and Star Cancellation Test (SCT) were used as unilateral neglect test. For the analysis, the baseline and intervention period measurements were visually analyzed using graphs and mean values were used. Result : All three evaluations showed that the number of errors missed during the training period was lower than the baseline period, and this decrease remained after training. The error was reduced by an average of $2{\pm}1.2$ omissions and an average omissions of $0.6{\pm}0.5$ omitting an average of $4.5{\pm}1$ omissions in the line break test. As a result of the Albert test, the average error decreased by $22.5{\pm}1.9$ omissions and $8{\pm}7.3$ omissions and $0.3{\pm}0.5$ omissions, respectively. In the star clearance test, the average error decreased from $26{\pm}4.6$ to $21.8{\pm}1.7$ and $20{\pm}0$, respectively. Conclusion : In this study, vibrotactile stimulation therapy showed a continuous effect on improving unilateral neglect. Based on these findings, further research should be conducted in order to improve objectivity in future studies. Further research on various arbitration methods that maximize the effect of intervention will be needed.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.55-57
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• 2001

강화학습은 한 에이전트가 자신이 놓여진 환경으로부터의 보상을 최대화할 수 있는 최적의 행동 전략을 학습하는 것이다. 따라서 강화학습은 입력(상태)과 출력(행동)의 쌍으로 명확한 훈련 예들이 제공되는 교사 학습과는 다르다. 특히 Q-학습과 같은 비 모델 기반(model-free)의 강화학습은 사전에 환경에 대한 별다른 모델을 설정하거나 학습할 필요가 없으며 다양한 상태와 행동들을 충분히 자주 경험할 수만 있으면 최적의 행동전략에 도달할 수 있어 다양한 응용분야에 적용되고 있다. 하지만 실제 응용분야에서 Q-학습과 같은 강화학습이 겪는 최대의 문제는 큰 상태 공간을 갖는 문제의 경우에는 적절한 시간 내에 각 상태와 행동들에 대한 최적의 Q값에 수렴할 수 없어 효과를 거두기 어렵다는 점이다. 이런 문제점을 고려하여 본 논문에서는 로봇 축구 시뮬레이션 환경에서 각 선수 에이전트의 동적 위치 결정을 위해 효과적인 새로운 Q-학습 방법을 제안한다. 이 방법은 원래 문제의 상태공간을 몇 개의 작은 모듈들로 나누고 이들의 개별적인 Q-학습 결과를 단순히 결합하는 종래의 모듈화 Q-학습(Modular Q-Learning)을 개선하여, 보상에 끼친 각 모듈의 기여도에 따라 모듈들의 학습결과를 적응적으로 결합하는 방법이다. 이와 같은 적응적 중재에 기초한 모듈화 Q-학습법(Adaptive Mediation based Modular Q-Learning, AMMQL)은 종래의 모듈화 Q-학습법의 장점과 마찬가지로 큰 상태공간의 문제를 해결할 수 있을 뿐 아니라 보다 동적인 환경변화에 유연하게 적응하여 새로운 행동 전략을 학습할 수 있다는 장점을 추가로 가질 수 있다. 이러한 특성을 지닌 AMMQL 학습법은 로봇축구와 같이 끊임없이 실시간적으로 변화가 일어나는 다중 에이전트 환경에서 특히 높은 효과를 볼 수 있다. 본 논문에서는 AMMQL 학습방법의 개념을 소개하고, 로봇축구 에이전트의 동적 위치 결정을 위한 학습에 어떻게 이 학습방법을 적용할 수 있는지 세부 설계를 제시한다.

• Journal of Digital Contents Society
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• v.8 no.3
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• pp.309-314
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• 2007

A decision tree algorithm should be modified to be suitable in distributed and collaborative environments for distributed data mining. The distributed data mining system proposed in this paper consists of several agents and a mediator. Each agent deals with a local data mining for data in each local site and communicates with one another to build the global decision tree model. The mediator helps several agents to efficiently communicate among them. One of advantages in distributed data mining is to save much time to analyze huge data with several agents. The paper focuses on a transfer technique among agents dealing with each local decision tree model to reduce huge overhead in communication among them.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.3
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• pp.1-9
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• 2010

In recent year, the cores of ubiquitous environment are sensor networks and RFID systems. RFID system transmits the electronic information of the tag to the reader by using RF signal. Collision happens in RFID system when there are many matched tags, and it degrades the tag identification performance. Such a system needs algorithm which is able to arbitrate tag collision. This paper suggests a hybrid method which reduces collision between the tags, and can quickly identify the tag. The proposed method operates based on certainty, which takes an advantage of tree based algorithm, and to reduce collision it selects transmission time slot by using tag ID. The simulation results show the suggested method has higher performance in the number of queries and collision compared to other tree based and hybrid algorithms.

• Korean Journal of Psychosomatic Medicine
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• v.12 no.1
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• pp.56-65
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• 2004

Objectives: The aim of this study was to investigate the quality of life of caretaking family members who have a patient with psychiatric disorders. The results will be served as a basic data of ameliorating the quality of life of caregivers. Methods: 78 caretaking family members who have a patient with schizophrenia and 54 caretaking family members who have a patient with alcohol dependence, a total of 132 persons completed the questionnaire, and analyzed. The Korean version of the SmithKline Beecham Quality of Life Scale and the Family Burden Scale were applied. Results: There was no statistically significant correlation between burden and sex, age, income, and duration of living with patients before onset. The male caregiver showed higher quality of life than that of female. It showed statistically significant correlation between age and factor physical well-being and factor activity. 41% of variance of quality of life of caregivers were explained by the stress response, burden, and overall merits of the field of psychiatry, and the tension had the most explanatory power. Conclusion: The chronic illness may give a burden on caregivers, and that decrease the quality of life of caregivers. The longer duration of illness of patients, the lower quality of life of caregivers on competence factor. Therefore, the authors recommend the therapeutic modality must be offered to the caregivers who may experience the stress and burden.

• Therapeutic Science for Rehabilitation
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• v.10 no.1
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• pp.63-75
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• 2021

Objective : The purpose of this study was to examine the roles and practices of occupational therapists in public health centers based on their working experience of occupational therapists who are working in these facilities. Methods : We used Giorgi's descriptive phenomenological research method. Six occupational therapists were interviewed, and their recorded data were analyzed using Claizzi's thematic analysis. Results : As a result, 4 categories, 16 themes, and 24 elements were elicited. The major roles of occupational therapists in public health centers were the evaluation of clients, home-visit occupational therapy, management of dementia programs and community connection projects. Interventions that are needed to create a healthy community include case and program management, compensatory approaches, and healthy lifestyle interventions. The difficulties experienced by occupational therapists include their limited number job insecurity, performance-oriented administrative policy, and the lack of communication among professionals. Occupational therapists require education in health management and practice in public health centers to build their capacities. Conclusion : The results of this study could be used for guidelines for occupational therapists who work in community healthcare centers, as well as basic training for competent occupational therapists in the community.

• Korea Trade Review
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• v.43 no.5
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• pp.139-158
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• 2018

As trade volume increases and the business environment becomes more complex and competitive, international trade disputes are also increasing and becoming more complex. Parties need to become more aware of alternatives to costly and time consuming arbitration and litigation. The ADR (Alternative Dispute Resolution) can encompass all dispute resolution processed and can act as a substitute for traditional litigation. Mediation, a type of ADR, offers an amicable dispute settlement mechanism between concerned parties through a natural mediator. There are several strong points of mediation compared with litigation or arbitration. First of all, mediation can take place without having to complete time-consuming and expensive discovery processes associated with litigation. In addition, since mediation is considered a private process, the dispute can remain out of the public eye. It can be embarrassing and disrupt business when customer or suppliers learn that a company is involved in litigation. Lastly, mediation is less adversarial than litigation or arbitration, so the parties often can salvage their relationships. Often the parties to mediation find themselves continuing to conduct business. In spite of such benefits of mediation, it is less used in Korea and therefore, this article aims to promote the mediation system in international trade disputes. However, this paper has limitation, for example, why ADR is not used well in Korea and need to suggest how ADR can work best in international trade disputes.

• Journal of the Korean Society of Radiology
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• v.84 no.4
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• pp.809-823
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• 2023

Trauma is an injury to the body that involves multiple anatomical and pathophysiological changes caused by forces acting from outside the body. The number of patients with trauma is increasing as our society becomes more sophisticated. The importance and demand of traumatology are growing due to the development and spread of treatment and diagnostic technologies. In particular, damage to the large blood vessels of the chest can be life-threatening, and the sequelae are often severe; therefore, diagnostic and therapeutic methods are becoming increasingly important. Trauma to nonaortic vessels of the thorax and aorta results in varying degrees of physical damage depending on the mechanism of the accident and anatomical damage involved. The main damage is hemorrhage from non-aortic vessels of the thorax and aorta, accompanied by hemodynamic instability and coagulation disorders, which can be life-threatening. Immediate diagnosis and rapid therapeutic access can often improve the prognosis. The treatment of trauma can be surgical or interventional, depending on the patient's condition. Among them, interventional procedures are increasingly gaining popularity owing to their convenience, rapidity, and high therapeutic effectiveness, with increasing use in more trauma centers worldwide. Typical interventional procedures for patients with thoracic trauma include embolization for non-aortic injuries and thoracic endovascular aortic repair for aortic injuries. These procedures have many advantages over surgical treatments, such as fewer internal or surgical side effects, and can be performed more quickly than surgical procedures, contributing to improved outcomes for patients with trauma.