GaAs MESFET의 광특성에 관한 해석적 이론

권요한,정해양 慶熙大學校 레이저 工學硏究所 1997 레이저공학 Vol.8 No.-

In this paper, we analyzed d. c. and microwave characteristics of GaAs-MESFET under laser illumination. We obtained the analytical expression of I-V characteristics of GaAs-MESFET for linear, knee and saturation regions by solving 2-dimensional Poisson's equation and compared calculated I-V curves with experimental data. The resulting I-V curves are in good agreement with experimental data. We also obtained the analytical expressions for the current gain cut-off frequency f?? and time constant for the linear and the knee region, respectively. It was predicted that the reduction of the current gain cut-off frequency and the increase time constant due to the photovoltaic effect under laser illumination.

시각 특성을 고려한 웨이브릿 변환 비디오 압축

양해권,김진태 群山大學校 情報通信技術硏究所 1998 情報通信技術硏究論文集 Vol.2 No.-

In this paper, we will compress the data of video signal using motion compensation and wavelet transform method. It is abbreviate to process have not large gain that analysing human visual characteristic for video signal and is compressed to the high portion without low resolution for video signal by abbreviated unsensitive information for human visual. In the result of simulation with 'Football' and 'People', we get high resolution under compress of frame per 30:1.

고등학생의 열등감과 학업적 자기효능감을 위한 Adlerian 집단상담의 효과 분석

권기양,심혜숙 부산대학교 과학교육연구소 2005 교사교육연구 Vol.44 No.-

The purpose of this study is to investigate the effects of Adlerian Group Counseling Program which was based on individual psychology on inferiority feelings and academic self-efficacy of the academic high school students. For this study, the following hypotheses were established. First, there would be significant decrease in inferiority symptoms including three subordinate factors (sensitiveness, negativeness, retreat) for high school students after the treatment. Second, there would be significant increase in academic self-efficacy including three subordinate factors (self-confidence, self-regulatory efficacy, task difficulty preference) for high school students after the treatment. The subjects of this study were 27 first grade students of academic high school in Busan. 12 students were assigned to an experimental group and 15 were assigned to a control group. The study progressed through three stages : pre-test, experimental intervention (participation in the program by the experimental group), post-test. The experimental group participated in 15 sessions of 50 minutes each over six months. Inferiority Symptom scale (Yim, Gie-Hong) and Academic Self-efficacy scale (Kim Ah-yeong, Park In-yeong) were administrated in both experimental and control group.The results from this study were as follows; First, Adlerian Group Counseling Program significantly decreased the total scores in inferiority symptoms and the each score in three subordinate factors (sensitiveness, negativeness, retreat) for the experimental group subjects. Second, Adlerian Group Counseling Program significantly increased the total scores in the academic self-efficacy and the each score in three subordinate factors (self-confidence, self- regulatory efficacy, task difficulty preference) for the experimental group subjects. Based on the above results, it can be concluded that Adlerian Group Counseling Program is very effective in helping the high school students reduce the level of inferiority symptoms and elevate the level of their academic self-efficacy. Therefore, Adlerian Group Counseling Program can be strongly suggested as a useful means for high school students' self-growth and improvement for their fruitful school lives.

디버깅 트레이서의 설계 및 구현에 관한 연구

梁海權,李英魯,金仁洙 군산대학교 1987 論文集 Vol.14 No.-

Until now, many programmers debug a program using the primitive method of inserting print statements into the high level language program.This results in a time consuming cycle of deiting, Compliing and testing until the bug is found. In this paper, to trace the lines and variables in the interactive system, We design the simulator and interpret the object program.

집선장치를 이용한 ISDN 기본 액세스 다중화에서의 호손율 계산

梁海權,金仁洙 군산대학교 1988 論文集 Vol.15 No.-

This paper describes the separated line concentrator and the joint line concentrator to multiplex the traffic with different kinds of transmission rates.In multiplexing of ISDN basic access subscribers using these concentrators, this paper shows the increased number of input channels to maintain the acceptable value of blocking probability

데이타베이스에 있어서의 시간지원 구현에 관한 연구

梁海權,김광훈,박용문 군산대학교 1987 論文集 Vol.14 No.-

Recently, the need for supporting time varying information in databases has been recognized for quite some time.Thus, attention has been focused on Temporal Databases, representing an enterprise over time.Many authors have proposed numerous schemes to satisfy this need by incorporating one or two time attributes in the database. In this paper, We have introduced to this field, and surveyed a taxonomy of time and implementation issues which are the versioning methods, storage structures, and it's performance evaluation, and suggested the versioning method, storage structure, and approach to the development of a model for DBMS with time and revision-history supporting. And we'll expend this paper to design and develop the relational DBMS with time and revision history supporting.

ATM 망에서 ABR 서비스를 위한 속도기반 및 크레이트기반 흐름제어의 연동성능 분석

양해권,안탁현 群山大學校 情報通信技術硏究所 1999 情報通信技術硏究論文集 Vol.3 No.-

The ATM Forum has been focusing on flow control mechanism for ABR traffic management. The goal of this activity is to efficiently manage the leftover network bandwidth and fairly distribute it among contending ABR VC so that communication links can be optimally utilized ABR traffic is difficult to predict traffic shape because it has bursts and variable behavior. Also it's sensitive to lose but not to delay. This behavior makes difficult to UPC function in network and cause of congestion in switch, thus performance is degraded. To resolve this problem, various flow control mechanism has been worked in the ATM Forum. Especially, the rate-based flow control mechanism for ABR traffic has been standardized in the ATM Forum, Sept. 1994. Thus, various flow control mechanism has been working which liked EFCI, ER, VS/VD. VS/VD control is superior than existed ER ontrol because it isolate different networks from each other. In this paper, we propose an expanded VS/VD flow control algorithm and compare with existed VS/VD flow control algorithm. Simulation result shows that this algorithm improve a problem in aspect of delay and buffer occupancy and provide a better performance to ABR service in response time, throughput and link rate.

직업적 아크릴아미드 폭로에 의한 다발성 신경병증

정해관,권용욱,어경윤,김병준,양정선,정철,진영우,이미영,강성규 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.3

Authors report a first Korean case of polyneuropathy in an acrylamide producing factory together with an environmental and epidemiologic survey for the ten workers of the same workplace and 46 workers in the production and manufacturing acrylamide in Ulsan, Korea. The case is 30 years old man who worked in the production of the acrylamide for two years. In August, 1997, he had a weakness of the lower extremity with loss of body weight of 15 Kg which progressed to paresthesia of the limbs, the loss of vibration sense, difficulty in walking, speech disturbance, dysuria, constipation, difficulty in erection and swallowing difficulty. Neurologic examination showed a complete loss of vibration and position sense, and loss of deep tendon reflex in all the limbs. There was a contact dermatitis-like skin lesion on the feet. Electrodiagnostic test showed a generalized polyneuropathy of moderate degree involving motor and sensory component of peripheral and cranial nerves. After 8 months' cessation from exposure and supportive care, his symptoms were completely resolved, but abnormality in electrodiagnostic test and vibrotactile perception threshold still persisted, although much improved than before. There were 11 workers in the same workplace of the case, producing acrylamide by microorganism as a catalyst. Environmental monitoring of the workplace revealed air borne concentration of the acrylamide to be from 0.05 to 0.23 mg/m3 by personal sampling and from 7.65 to 11.65 mg/m3 by area sampling during filter exchanging process, which far exceeds TLV-TWA of 0.03 mg/m3. However, acrylamide was not detected from the plasma of the workers. Symptom questionnaire showed a markedly higher complain of neurologic symptoms, compared to the workers of the other acrylamide producing companies. Electrodiagnostic test showed a several workers are in the lower normal range without definite abnormality. Vibrotactile perception threshold by Vibratron Ⅱ showed a significantly increased threshold in the workers of the same workplace compared to the other acrylamide workers and significantly decreased test score of color vision compared to normal controls. After improvement of the production process and strict wearing of the protective device, most workers reported the improvement of clinical symptoms, but vibrotactile perception threshold was not improved. These result suggests the need for the effective environmental monitoring together with a periodic biological monitoring. Development of effective screening test is urgently needed to control and assess the skin absorption of acrylamide.

ATM 망에서 MARS와 RSVP를 이용한 효율적인 IP 멀티캐스팅

김진수,양혜권 국립7개대학공동논문집간행위원회 2001 공업기술연구 Vol.1 No.-

Various multi-media applications are occured as Internet expanded. Real-time Internet multi-media service, for example audiovisual-conference, Internet-broadcasting and VOD, require fast data transmission, QoS, IP multicast. MARS is porposed to support IP multicast in the ATM Networks based on Internet, and RSVP is proposed to guarantee QoS in the Internet which is originally based on only best-effort service. In this paper, we propose two mechanisms to support IP multicast service involving QoS support over the ATM networks with MARS architecture based on multiple MCSs. In the first mechanism, when an ATM host requests joining into a specific multicast group, the MARS selects a proper MCS among the multiple MCSs to minimize the average time of transfer delay between the sender and the group members. In the second mechanism, when the RSVP reservation message from group member arrive at the MARS, the MARS which can process the RSVP reservation message select again the MCS with using the MCS management table. Fially, we recommend the mechanism to keep the QoS of Internet service and to reduce the the processing-overhead between MARS and MCS.

재래(흑색) 염소의 비육에 관한 연구 : Ⅰ. 일측 갑상선 제거가 체중, 체온 및 맥박에 미치는 영향 Ⅰ. Effect of Uni-lateral Thyroidectomy on Body Weight, Body Temperature and Pulse Rate

박무현,권해병,양일석 慶尙大學校 1975 論文集 Vol.14 No.-

In order to investigate the relationship of body weight, body temperature and pulse rate to hypothyroidism in the state of uni-lateral thyroidectomy of Korean native goat, a brief observation was carried out. Twenty healthy male adult goats (7 months old) were used in the present experiment dividing into 2 groups, the control with 5 and the experimental with 15, respectively. Individuals of the experimental group were received uni-lateral thyroidectomy by surgical operation, while individuals of the control group, on the other hand, were received sham-operation. Measurements of body weight, body temperature and pulse rate after the operation were performed in duration of 48 days by 2 days interval. The results obtained could be summerized as follows. 1. There were no significant changes in body weight of experimental group compared to that of control group. 2. Uni-laterally thyroidectomized goat showed no changes in body temperature, which is seemed to he doe to a compensatory effect. 3. Statistical calculation did not show any difference in pulse rate between control and experimental group. The present experiment can he concluded that uni-lateral thyroidetomy had not any effect on the changes body weight, body temperature and pulse rate.