• Title/Summary/Keyword: ns-2

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A Research about Adding a New Network Component in Network Simulator 2 (Network Simulator 2에서의 새로운 Network Component 추가에 관한 연구)

  • 안혜환;손재기
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10c
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    • pp.70-72
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    • 2004
  • 본 논문은 NS-2 에서의 새로운 네트워크 요소 모듈 개발에 관한 연구를 목적으로 한다. 현재 대부분의 새로운 네트워크 요소들은 경제적인 이유와 네트워크의 환경적인 제약으로 인해서 시뮬레이터 환경에서 실험 되어지고 컴퓨터 공학에서 가장 많이 알려진 시뮬레이션툴 중의 하나로 NS-2 가 많이 사용되어 지고 있다 이러한 NS-2 는 Otcl 이라는 MIT 에서 개발한 언어와 C++ 가 상호 연동 되어져서 이벤트 처리 부분은 OTcl 이 담당하고 패킷 처리 부분은 C++가 담당 하고 있지만 새로운 네트워크 요소를 추가 하는 부분을 이해 하기에는 현재 공개된 문서 만으로는 이해하기 어려운 부분이 많다. 본 논문에서는 NS-2 에 새로운 네트워크 요소를 추가 하는대 있어서 필요한 NS-2 의 기술적인 부분을 설명함을 목적으로 하였다.

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Cupric Complexes Produced from the Reaction of Cupric Nitrate Trihydrate with S-2-Pyridyl Thioates

  • Choi, Young-Nam;So, Hyun-Soo;Lee, Jae-In;Kim, Sung-Gak
    • Bulletin of the Korean Chemical Society
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    • v.7 no.5
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    • pp.385-388
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    • 1986
  • The reaction of cupric nitrate trihydrate with S-2-pyridyl thioates in acetonitrile was studied. The major products were the corresponding carboxylic acids and $[Cu(NO_3)(C_5H_4NS)(C_5H_5NS$)] (Complex A). Sometimes $[Cu(NO_3)(C_5H_4NS)(H_2O$)] was also obtained in addition to Complex A. When Complex A was recrystallized in dimethylsulfoxide, $[Cu(NO_3)(C_5H_4NS)(C_5H_5NS)$ {$(CH_3)_2SO$}$_2]{\cdot}2H_2O$ was crystallized. The structures of these copper complexes and the role of cupric nitrate in the hydrolysis of S-2-pyridyl thioates are discussed.

The Use of Nutritional Supplements in Korean Elite Soccer Players (한국 프로축구 선수들의 영양보충제 섭취 실태)

  • Lee Hyun-Sook
    • Journal of Nutrition and Health
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    • v.39 no.3
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    • pp.299-306
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    • 2006
  • This study was done to investigate the use of nutritional supplements (NS) in Korean elite soccer players using an anonymous questionnaire. NS were classified into health supplements, manufactured health food supplements, chinese medicines & tonic foods, and nutrient supplements. Information was sought on the type of NS and factors that might influence supplement use including selected demographic parameters and health related variables. The data were collected from 241 athletes (aged $24.6{\pm}3.8$ years) in 9 professional soccer club. The prevalence of NS use among the subjects was 81.3%. Health supplements were used most frequently and nutrient supplement drug was the second one. Among the health supplements, weight/muscle gainer and calorie replacement product were most frequently used. Vitamin supplements were most frequently used among all nutrient supplement drugs. Users of NS were higher age (p<0.05) duration of exercise (p<0.05), and income (p<0.05) than non-users. The married (p<0.05) and a member of K-league (p<0.01) tended to have higher prevalence of NS use. The main adviser of NS were family (55.3%) and oneself (39%) instead of coach or sports nutritionist. Although NS use, only 26.2% certainly check up nutritional information on their used NS. Among the subjects, 84.5% of them felt that NS use were improved athletic performance, and 86.5% of them will to keep on taking supplement. These data suggest that a large number of elite soccer players use NS and these players may require education about healthy nutritional supplement practice and on the proper use of nutritional supplements.

Busy-tone PHY Module with IEEE 802.11 Design and Implementation in NS-2 (NS-2에서 IEEE 802.11의 Busy-tone PHY 모듈 설계 및 구현)

  • Yoo, Dae-Hun;Choi, Woong-Chul
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.7
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    • pp.189-197
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    • 2008
  • ENS-2 simulator is the most widely-used simulator in the research of wired/wireless communication. Since an IEEE 802.11 module has been implemented in NS-2. much research using this module has been done for various MAC layer functions. The most important problem in terms of performance is the hidden terminal problem. To solve this problem, the solutions using a busy-tone such as BTMA, DBTMA, etc. have been proposed. In order to be able to use a busy-tone, channels using the frequency bandwidth except the frequency bandwidth of the data channel is required for the collision prevention, and a MAC layer has to be able to menage such multiple channels. In this research, we implement a module that can use a busy-tone in NS-2, implement a modified RI-BTMA by applying the implemented module, and verify its performance.

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Analysis of Effects of Hidden Nodes and CCA Deferment Algorithm on IEEE 802.15.4 Performance Using ns-2 Simulator (ns-2 시뮬레이터를 이용한 은닉 노드와 CCA 지연 알고리즘이 IEEE 802.15.4 네트워크의 성능에 미치는 영향 분석)

  • Lee, Kang-Woo;Hyun, Gyu-Wan;Shin, Youn-Soon;Ahn, Jong-Suk
    • The KIPS Transactions:PartC
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    • v.16C no.3
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    • pp.393-406
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    • 2009
  • This paper introduces two functions added to the current version of ns-2 simulator for better accuracy of IEEE 802.15.4 network simulations. The first one is to automatically place hidden nodes over the ring topology in which the coordinator is centered, when the number of hidden nodes and total number of nodes is given. Collisions of signals can be distinguished into the trace file according to the ways of participation of hidden nodes. The second one is the CCA deferment algorithm described in IEEE 802.15.4-2006 standard which is not implemented in the current version of ns-2. Owing to these additional functions, we can carry out the precise analysis of the performance effects of hidden nodes and CCA deferment algorithm on 802.15.4 networks. Simulation results present at least 66% of performance degradation in throughput and drastic increase of collision probability up to 90% from 65% by just a single hidden node. Besides, 2006 standard for CCA deferment algorithm gives 19% lower collision probability and 38% higher performance.

Identification and in silico analysis of two types of serpin genes from expressed sequence tags (ESTs) of the Oriental land snail, Nesiohelix samarangae (동양달팽이 (Nesiohelix samarangae) 의 expressed sequence tags (ESTs) 로부터 분리한 2종류의 Serpin 유전자 분석)

  • Park, So Young;Jeong, Ji Eun;Hwang, Hee Ju;Wang, Tae Hun;Park, Eun Bi;Kim, Yong Min;Lee, Jun-Sang;Han, Yeon Soo;Yang, Seung-Ha;Lee, Yong Seok
    • The Korean Journal of Malacology
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    • v.30 no.2
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    • pp.155-163
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    • 2014
  • Serpins are a group of proteins involved in the regulation of serine and other type of proteases, and have been identified in many kinds of organisms from invertebrates to vertebrates. Serpins are known to regulate the proteolytic cascades of the innate immune pathways in addition to their roles in blood coagulation, angiogenesis, fibrinolysis, inflammation and tumor suppression. In this study, we have isolated two partial serpin gene fragments from expressed sequence tags (ESTs) of Nesiohelix samarangae. Dotplot analysis indicates that they are of two different types, Ns-serpin type 1 and Ns-serpin type 2. Ns-serpin type 1 has 819 bp coding region (272 amino acids), whereas Ns-serpin type 2 has 555 bp coding region (185 amino acids). Molecular phylogenetic analysis shows that the identified serpins have high similarities to their counterparts in the California see slug, Aplysia californica. Yet, the precise biological and immunological roles of these Ns-serpins remain to be further investigated using RNA interference and other molecular techniques.

Ginsenosides Have a Suppressive Effect on c-Fos Expression in Brain and Reduce Cardiovascular Responses Increased by Noxious Stimulation to the Rat Tooth

  • Jung, Ji-Yeon;Seong, Kyung-Joo;Moon, In-Ohk;Cho, Jin-Hyoung;Kim, Sun-Hun;Kim, Won-Jae
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.2
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    • pp.121-125
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    • 2013
  • The purpose of this study is to investigate the antinociceptive effects of ginsenosides on toothache. c-Fos immunoreactive (IR) neurons were examined after noxious intrapulpal stimulation (NS) by intrapulpal injection of 2 M KCl into upper and lower incisor pulps exposed by bone cutter in Sprague Dawley rats. The number of Fos-IR neurons was increased in the trigeminal subnucleus caudalis (Vc) and the transitional region between Vc and subnucleus interpolaris (Vi) by NS to tooth. The intradental NS raised arterial blood pressure (BP) and heart rate (HR). The number of Fos-IR neurons was also enhanced in thalamic ventral posteromedial nucleus (VPMN) and centrolateral nucleus (CLN) by NS to tooth. The intradental NS increased the number of Fos-IR neurons in the nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (RVLM), hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN), central cardiovascular regulation centers. Ginsenosides reduced the number of c-Fos-IR increased by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Naloxone, an opioid antagonist, did not block the effect of ginsenoside on the number of Fos-IR neurons enhanced by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Ginsenosides ameliorated arterial BP and HR raised by NS to tooth and reduced the number of Fos-IR neurons increased by NS to tooth in the NTS, RVLM, hypothalamic SON, and PVN. These results suggest that ginsenosides have an antinociceptive effect on toothache through non-opioid system and attenuates BP and HR increased by NS to tooth.

Effects of Surimi and Starch on the Quality Properties of Mackerel Scomber japonicus Sausage (Surimi 및 전분 첨가에 따른 고등어S(comber japonicus) 소시지의 품질 특성)

  • Kim, Koth-Bong-Woo-Ri;Jeong, Da-Hyun;Pak, Won-Min;Kim, Bo-Ram;Kang, Ja-Eun;Park, Hong-Min;Ahn, Dong-Hyun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.6
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    • pp.739-745
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    • 2013
  • This study was conducted to evaluate the qualities of mackerel Scomber japonicus sausage prepared with Theragra chalcogramma surimi (TS, A grade), Nemipterus virgatus surimi (NS, A grade) (0, 5, 7, 10%), and 7% NS with starch (0, 1, 2, 3%). The whiteness of the mackerel sausage was significantly increased by adding TS and NS, but that of the NS with starch groups was decreased compared with the control. The hardness increased significantly with the addition of TS, whereas the NS and NS with starch groups showed no considerable differences compared with the control. The gel strength was not significantly different among the mackerel sausage additive groups. In the sensory evaluation, the mackerel sausages containing 5% TS, 7% NS, and 7% NS with 2% starch had the highest overall preference. In conclusion, these results suggest that 5% TS, 7% NS, and 7% NS with 2% starch improve the quality, texture and sensory properties of mackerel sausage.

Modification of Extended Version of IEEE 802.11 in ns-2 and Performance Analysis with Error Rate Using Computer Simulation (ns-2에서 IEEE 802.11 확장 모듈의 오류 수정과 Error Rate를 적용한 시뮬레이션 및 성능분석)

  • Jung, Jin-Uk;Jin, Kyo-Hong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.9
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    • pp.2008-2015
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    • 2010
  • Ns-2 is a proven simulator which is widely utilized to evaluate the performance of wired and wireless network. Ns-2.33 version introduced the extended version including the modules which the core functions of existing 802.11 PHY and MAC layer are implemented. However, if the error rate, one of most important parameters to evaluate a performance of wireless network, is applied to the extended version, the simulation is ceased with several fatal errors. Furthermore, a packet error is detected and discarded on MAC layer in the traditional protocol architecture, but there is the problem which can't identify information about a packet with error by processing packet error on PHY layer in this version. In this paper, we modify the extended version to resolve the above mentioned problems. And also we perform ns-2 simulation using the modified version on the IEEE 802.11p based vehicular ad-hoc networks, and then analyze effects of error rate.

Quasi-nonvolatile Memory Characteristics of Silicon Nanosheet Feedback Field-effect Transistors (실리콘 나노시트 피드백 전계효과 트랜지스터의 준비휘발성 메모리 특성 연구)

  • Seungho Ryu;Hyojoo Heo;Kyoungah Cho;Sangsig Kim
    • Journal of IKEEE
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    • v.27 no.4
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    • pp.386-390
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    • 2023
  • In this study, we examined the quasi-nonvolatile memory characteristics of silicon nanosheet (SiNS) feedback field-effect transistors (FBFETs) fabricated using a complementary metal-oxide-semiconductor process. The SiNS channel layers fabricated by photoresist overexposure method had a width of approximately 180 nm and a height of 70 nm. The SiNS FBFETs operated in a positive feedback loop mechanism and exhibited an extremely low subthreshold swing of 1.1 mV/dec and a high ON/OFF current ratio of 2.4×107. Moreover, SiNS FBFETs represented long retention time of 50 seconds, indicating the quasi-nonvolatile memory characteristics.