• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.4
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• pp.68-77
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• 1996

In this paper, we investigate the effect of a LAN traffic on the performance of a shared buffer ATM switch andIWF (interworking function )on a LAN environment through simulations. Firstly, the delay and the buffer occupancy of the switch and IWF are mesured according to the proportion of the LAN traffic to the traffic generated by gernoulli process. Secondly, we investigate the behavior of the switch in the case that LAN traffic is concentrated to a connectionless server, and the effect of LAN traffic shaping at IWF on the delay and the buffer occupancy of the switch.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.525-534
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• 2012

This study was conducted to classify community and verify vegetation structure of Picea jezoensis community in subalpine zone of Mt. Kyebang, Mt. Jiri, Mt. Deogyu, 39 releves set up and was carried out to analyze ordination. P. jezoensis Community was classified into Acer ukurunduense subcommunity, Quercus mongolica subcommunity, Syringa reticulata var. mandshurica subcommunity and P. jezoensis typical subcommunity. The order of important value of the forest community with DBH 2cm above plants was P. jezoensis (89.22), Acer komarovii (30.50), Abies koreana (18.81), Rhododendron schlippenbachii (18.10), Sorbus commixta (17.19), Betula ermanii (16.89), Pinus koraiensis (16.80), Taxus cuspidata (12.45), Acer ukurunduense (11.73). The DBH analysis suggests that P. jezoensis will maintain dominant position.

• Korean Journal of Child Studies
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• v.25 no.3
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• pp.75-85
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• 2004

This study was to investigate parental rearing attitudes which are perceived by the only children and sibling children and their socio-emotional development. The subjects were 426 4th and 6th grade students in an elementary school located in Seoul and Kyonggi-do. The data was analyzed by SPSS WIN computer program. Two-way ANOVA and Multiple Regression analyses were performed. Within group variables that predicted children's socio-emotional development were parental achievemental, loving and autonomous attitude, and school-aged children's socio-emotional development was most predicted by parental achievemental attitude.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.383-389
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• 2010

The vapor concentration of hexane in a liquid spray jet in crossflow was qualitatively measured on the basis of the infrared (IR) extinction techniques. The objectives of the present study are to understand the whole evaporation process from droplet breakup to vapor and to confirm the usefulness of IR emission method in a lab-scale ramjet combustor. From the experimental results, we concluded that hexane vapor mole fraction increased with temperature rise and kept nearly constant during the variation of fuel to air momentum ratio.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.12a
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• pp.61-64
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• 2000

EZW 알고리듬을 수행하는 동안 네 가지의 심벌 (POS, NEG, IZ, ZT)을 사용하게 된다. 하지만 POS 또는 NEG 심벌을 가지는 계수들의 하위밴드의 계수들이 모두 ZT 심벌을 가질 경우 도미넌트 계수열을 만드는데 있어서 데이터의 낭비가 심하다. 이러한 단점을 보완하기 위해 여섯개의 심벌(POS, NEG, IPOS, INEG, IZ, ZT)을 이용한 알고리듬이 제안된 바 있다. 하지만 경우에 따라서 4개의 심벌을 이용한 본래의 알고리듬보다 왜곡이 심한 경우가 간혹 발생하게 된다. 본 논문에서는 네 개의 심볼(LS, IS, IZ, ZT)을 이용한 새로운 알고리듬을 제안한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.413-414
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• 2015

SDN은 네트워크 장비의 control plane과 data plane을 분리하고, 중앙의 컨트롤러를 통해 네트워크를 제어한다. 네트워크 운영에서 monitoring은 필수적인 요소이며, SDN 환경에서의 기존의 monitoring 방법인 OpenTM은 in-band network 환경을 고려하지 않았다. 본 논문은 in-band network 환경에서 hop-count와 정확도를 고려하여 높은 정확도를 유지하면서도 네트워크 부하를 줄일 수 monitoring 방법을 제안한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.11a
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• pp.718-721
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• 2012

PMIPv6 (Proxy Mobile IPv6)는 네트워크 기반 이동성 지원 프로토콜로 MN (Mobile Node)의 이동성 프로토콜 스택 유무와 관계없이 MN의 이동성을 지원한다. 하지만 핸드오버 과정에서 이동성 관련 시그널링을 완료할 때까지 지연이 발생하고 핸드오버 동안 MN으로 향하는 패킷이 손실된다는 단점을 갖고 있다. 이러한 단점을 보완하기 위한 기법으로 FPMIPv6 (Fast Handover for PMIPv6)가 제안되었다. 본 논문에서는 PMIPv6의 오픈소스인 OAI PMIPv6 (OpenAirInterface PMIPv6)를 기반으로 FPMIPv6 테스트베드를 구축하고 MN의 핸드오버를 실험하여 실제 FPMIPv6 환경에서의 핸드오버 지연 및 패킷 손실 정도를 측정한다.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.5
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• pp.219-224
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• 2015

In this paper, the designed fish robots DOMI ver1.0 is researched and development for aquarium underwater robot. The presented fish robot consists of the head, 1'st stage body, 2nd stage body and tail, which is connected two point driving joints. The model of the robot fish is analysis to maximize the momentum of the robot fish and the body of the robot is designed through the analysis of the biological fish swimming. Also, Lighthill was applied to the kinematics analysis of robot fish swimming algorithms, we are applied to the approximate method of the streamer model that utilizes techniques mimic the biological fish. The swimming robot has two operating mode such as manual and autonomous operation modes. In manual mode the fish robot is operated to using the RF transceiver, and in autonomous mode the robot is controlled by microprocessor board that is consist PSD sensor for the object recognition and avoidance. In order to the submerged and emerged, the robot has the bladder device in a head portion. The robot gravity center weight is transferred to a one-axis sliding and it is possible to the submerged and emerged of DOMI robot by the breath unit. It was verified by the performance test of this design robot DOMI ver1.0. It was confirmed that excellent performance, such as driving force, durability and water resistance through the underwater field test.

• Korean journal of applied entomology
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• v.49 no.2
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• pp.151-158
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• 2010

Among 18 Bacillus thuringiensis isolates with spherical parasporal inclusion from soils, B. thuringiensis subsp. israelensis CAB199 was selected. It was showing over 90% mortality against Aedes aegypti and Culex pipiens moletus. It was confirmed that this B. thuringiensis subsp. israelensis CAB199 isolate also had a insecticidal activity against Culex inatomii that was occurred in the marsh. Because most of mosquito larva were primarily situated or shifted from under- to surface water, we need to select long floating formulations on surface water for controlling mosquito larva. It was tested the pesticidal and control effects in the laboratory and wetland with two formulation types of B. thuringiensis subsp. israelensis, for example, wettable power (WP) and suspension concentrate type (SC). Laboratory test showed that SC formulation type was relatively faster and more effective against 3 tested mosquito species, C. pipiens, Aedes aegypti, and C. inatomii. Otherwise, the control efficacy of SC formulation type was more rapidly appeared against C. inatomii in the wetland.

• Journal of the Korean Geotechnical Society
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• v.21 no.7
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• pp.31-42
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• 2005

In this study, a rockfill-dam material was investigated on its shear strength and compressibility by performing large-scaled triaxial and oedometer tests. The rockfill material was compacted at two different compaction levels and sheared in triaxial compression at three different confining stresses. Also, rockfill samples were prepared to have three different grain size distributions but the same dry density. Each sample with a given grain size distribution was then compressed one-dimensionally in a large-scaled oedometer cell with and without soaking. The rockfill samples exhibited slightly different shear behaviors with the varying compaction and confining stress levels. The increase in the compaction level changed the behavior from contractive to dilative. Dilation decreased gradually with increasing confining stress, resulting in reduction in the peak shear strength. The large-scaled oedometer test results showed that particle breakages increased with increasing average particle sizes of the samples. Comparing the samples with different gradations, a relatively well-graded sample exhibited lower compressibility. For saturated samples, slightly higher deformations were observed, compared to dry samples. The values of tangent constrained modulis for the dry samples were larger by about 10 to 20$\%$, on the average, than those for the saturated samples.