• Title/Summary/Keyword: Ns-2

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MAC protocol based on Single-channel Jamming Signal in the Multi-Hop Ad Hoc Network (Multi-Hop Ad Hoc Network용 Single-channel Jamming 신호 기반 MAC 프로토콜)

  • Kim, Young-Man;Han, Wang-Won;Park, Hong-Jae;Jung, Kyung-Tae;Choi, Nak-Gil
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07a
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    • pp.280-282
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    • 2005
  • 급변하는 컴퓨터 네트워킹 환경에서 이동화에 따른 무선통신의 비중이 날로 더해지고 있다. 본 논문에서는 무선 인터넷 프로토콜 표준인 IEEE 802.11의 문제점들을 분석하고, Multi-Hop Ad Hoc Network에서 성능 향상을 위하여 Single-channel Jamming 신호를 기반으로 한 SJMAC(Single-channel Jamming MAC) 프로토콜을 설계하고, NS2 모듈을 구현한 후에 성능 평가를 하였다. 기존 IEEE 802.11과의 성능 비교를 위하여 NS2 (Network Simulator2)[1]에 SJMAC 모듈을 추가하여 제안된 프로토콜의 성능을 검증한다.

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SNMP Based Routing Process for Hand Handoff (Fast Handoff를 위한 SNMP 기반의 라우팅 프로세스)

  • 유상훈;박수현;백두권
    • Proceedings of the Korea Society for Simulation Conference
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    • 2003.11a
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    • pp.139-144
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    • 2003
  • Mobile Node has to maintain communication as they move form place to place, so it doesn't guarantee Quality of Service(QoS). Fast Handoff is important to provide multimedia and real-time applications services in mobile, and it is closely related to handoff delay. Therefore, handoff delay problem is actively studied to quarantee QoS as a main issue in mobile IP research area. Next generation Mobile IPv6 resolve this problem somewhat, triangle problem for first packet and handoff delay still remain. In this paper, we suggest SNMP Information-based routing that adds keyword management method to Information-based routing in active network in order to resolve such a problem, and then suggest QoS controlled handoff based on SNMP Information-Based routing. After modeling of suggested method and existing handoff method, simulations are carried out with NS-2 for performance evaluation. The results of simulations show the some improvement on handoff delay, and therefore on QoS improvement.

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Effect of Suckling Systems on Serum Oxytocin and Cortisol Concentrations and Behavior to a Novel Object in Beef Calves

  • Chen, Siyu;Tanaka, Shigefumi;Ogura, Shin-ichiro;Roh, Sanggun;Sato, Shusuke
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.11
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    • pp.1662-1668
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    • 2015
  • We investigated differences between effects of natural- and bucket-suckling methods on basal serum oxytocin (OT) and cortisol concentrations, and the effect of OT concentration on affiliative and investigative behavior of calves to a novel object. Ten Japanese Black calves, balanced with birth order, were allocated evenly to natural-suckling (NS) and bucket suckling (BS) groups. Blood samples were collected at the ages of 1 and 2 months (1 week after weaning) calves, and serum OT and cortisol concentrations were measured using enzyme-linked immunosorbent assay and enzymeimmunoassay tests, respectively. Each calf at the age of 2 months (2 weeks after weaning) was released into an open-field with a calf decoy, and its investigative and affiliative behaviors were recorded for 20 minutes. In 1-month-old calves, the basal serum OT concentration ($25.5{\pm}4.9$ [mean${\pm}$standard deviation, pg/mL]) of NS was significantly higher than that of BS ($16.9{\pm}6.7$) (p<0.05), whereas the basal cortisol concentration ($5.8{\pm}2.5$ [mean${\pm}$standard deviation, ng/mL]) of NS was significantly lower than that in BS ($10.0{\pm}2.8$) (p<0.05). Additionally, a negative correlation was noted between serum OT and cortisol concentrations in 1-month-old calves (p = 0.06). Further, the higher serum OT concentration the calves had at 1 month old, the more investigative the calves were at 2 months old but not affiliative in the open-field with a calf decoy. Thus, we concluded that the natural suckling method from a dam elevates the basal serum OT concentration in calves, and high serum OT concentrations induce investigative behavior and attenuate cortisol concentrations.

Design and Performance Analysis of Multi-hop Routing Protocol for WiMedia (WiMedia를 위한 멀티홉 라우팅 프로토콜 개발 및 성능분석)

  • Jung, Jin-Uk;Lee, Seung-Jin;Jin, Kyo-Hong;Hwang, Min-Tae;Jeon, Young-Ae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1406-1415
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    • 2012
  • Though WiMedia supports the higher data rates than other WPAN technologies, a WiMedia device cannot reach other devices which are apart from it more than 10 meter; the limited transmission range of the WiMedia protocol. In this paper, we propose a multi-hop QoS routing protocol to enable WiMedia devices to transmit real-time data to devices that is located out of transmission range. The proposed routing protocol is a hybrid routing protocol, which is the mixed protocol of table-driven and on-demand routing algorithm. In the proposed protocol, a route for a device within 2-hop is established by using the table-driven routing algorithm and a route for the device beyond 2-hop is established by using the on-demand routing algorithm. We perform ns-2 simulation to investigate the performance of the proposed routing protocol with AODV and DSDV. The simulation results show that the proposed protocol's performance is better than AODV and DSDV in terms of the throughput and delay.

Effect of Yukgunjatang Granule on Gastric Emptying in Rats (육군자탕(六君子湯)이 흰쥐의 위(胃) 배출능(排出能)에 미치는 영향)

  • Won, Jong-Man;Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
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    • v.28 no.2
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    • pp.242-249
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    • 2007
  • Backgrounds & Objectives : Yukgunjatanggranule (YGJT) ha been used for the treatment of functional dyspepsia, regarded as one of the gastric dysmotility diseases, but its mechanisms of cation are not yet well known, We investigated the effects of YGJT on gastric emptying and its mechanisms of action in rats. Methods : Gastric emptying was measured by glass beads (1mm in diameter) expelled from the stomach for 1 hour and 2 hours after administration ofnormal saline (NS) or YGJT 41.6mg/kg or 124.8mg/kg in rats. By the same method, gastric emptying was measured only for 2 hours after administration of NS of YGJT 124.8mg/kg in rats treated with atropine sulfate (1mg/kg, s.c), quinpirole HCl(0.3mg/kg, i.p.), NAME (NG-nitro-L-arginine methyl ester, 75mg/kg, s.c.) or cisplatin (10mg/kg, i.p.) to delay gastric emptying. Results : YGJT 124.8mg/kg improved gastric emptying more than NS or YGJT 41.6mg/kg (p=0.046). Under delayed gastric emptying, YGJT 124.8mg/kg improved gastric emptying in the group treated with cisplatin ($3.1{\pm}1.3$ vs. $6.6{\pm}3.1$, p=0.015), quinpirole HCl ($4.7{\pm}2.8$ vs. $5.5{\pm}5.6$, p=0.874) and NAME ($2.2{\pm}1.4$ vs. $4.7{\pm}6.0$, p=0.414), but aggravated it with atropine sulfate ($1.8{\pm}0.9$vs. $1.7{\pm}1.0$, p=0.957). Conclusions : YGJT improves gastric emptying through the cholinergic pathwas, and shows some effect against the toxicity of cisplatin. Therefore, we expect that it would be effective in relieving gastrointestinal symptoms in functional dyspepsia patients and cisplatin-treated patients.

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Evaluation of Applicability of SWAT-CUP Program for Hydrologic Parameter Calibration in Hardware Watershed (Hardware 유역의 수문매개변수 보정을 위한 SWAT-CUP 프로그램의 적용성 평가)

  • Sang Min, Kim
    • Journal of The Korean Society of Agricultural Engineers
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    • v.59 no.3
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    • pp.63-70
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    • 2017
  • The purpose of this study was to calibrate the hydrologic parameters of SWAT model and analyze the daily runoff for the study watershed using SWAT-CUP. The Hardware watershed is located in Virginia, USA. The watershed area is $356.15km^2$, and the land use accounts for 73.4 % of forest and 23.2 % of pasture. Input data for the SWAT model were obtained from the digital elevation map, landuse map, soil map and others. Water flow data from 1990 to 1994 was used for calibration and from 1997 to 2005 was for validation. The SUFI-2 module of the SWAT-CUP program was used to calibrate the hydrologic parameters. The parameters were calibrated for the highly sensitive parameters presented in previous studies. The P-factor, R-factor, $R^2$, Nash-Sutcliffe efficiency (NS), and average flow were used for the goodness-of-fit measures. The applicability of the model was evaluated by sequentially increasing the number of applied parameters from 4 to 11. In this study, 10-parameter set was accepted for calibration in consideration of goodness-of-fit measures. For the calibration period, P-factor was 0.85, R-factor was 1.76, $R^2$ was 0.51 and NS was 0.49. The model was validated using the adjusted ranges of selected parameters. For the validation period, P-factor was 0.78, R-factor was 1.60, $R^2$ was 0.60 and NS was 0.57.

Layer-specific cholinergic modulation of synaptic transmission in layer 2/3 pyramidal neurons of rat visual cortex

  • Cho, Kwang-Hyun;Lee, Seul-Yi;Joo, Kayoung;Rhie, Duck-Joo
    • The Korean Journal of Physiology and Pharmacology
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    • v.23 no.5
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    • pp.317-328
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    • 2019
  • It is known that top-down associative inputs terminate on distal apical dendrites in layer 1 while bottom-up sensory inputs terminate on perisomatic dendrites of layer 2/3 pyramidal neurons (L2/3 PyNs) in primary sensory cortex. Since studies on synaptic transmission in layer 1 are sparse, we investigated the basic properties and cholinergic modulation of synaptic transmission in layer 1 and compared them to those in perisomatic dendrites of L2/3 PyNs of rat primary visual cortex. Using extracellular stimulations of layer 1 and layer 4, we evoked excitatory postsynaptic current/potential in synapses in distal apical dendrites (L1-EPSC/L1-EPSP) and those in perisomatic dendrites (L4-EPSC/L4-EPSP), respectively. Kinetics of L1-EPSC was slower than that of L4-EPSC. L1-EPSC showed presynaptic depression while L4-EPSC was facilitating. In contrast, inhibitory postsynaptic currents showed similar paired-pulse ratio between layer 1 and layer 4 stimulations with depression only at 100 Hz. Cholinergic stimulation induced presynaptic depression by activating muscarinic receptors in excitatory and inhibitory synapses to similar extents in both inputs. However, nicotinic stimulation enhanced excitatory synaptic transmission by ~20% in L4-EPSC. Rectification index of AMPA receptors and AMPA/NMDA ratio were similar between synapses in distal apical and perisomatic dendrites. These results provide basic properties and cholinergic modulation of synaptic transmission between distal apical and perisomatic dendrites in L2/3 PyNs of the visual cortex, which might be important for controlling information processing balance depending on attentional state.

An Experimental Study on Pairwise Key Pre-distribution Schemes of Wireless Sensor Networks Considering 3D Environments (3D 환경을 고려한 무선 센서 네트워크의 키 사전 분배 기법 실험 연구)

  • Yun, Hyemin;Shin, Sooyeon;Kwon, Taekyoung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.6
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    • pp.975-980
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    • 2020
  • To protect wireless sensor networks (WSNs), various key distribution and management schemes have been proposed. However, most of them conducted simulations and experiments for performance evaluation by considering only the two-dimensional (2D) environments. In this paper, we investigate the effect of real-world three-dimensional (3D) topographic features on the key pre-distribution schemes for WSNs. For this purpose, we analyze and compare the performance of three pairwise key pre-distribution schemes in 2D and 3D environments: full pairwise (FP), random pairwise (RP), and full and random pairwise (FRP) schemes. For the experiments, we employ a network simulator NS-3 and 3D graphic tools such as Blender and Unity. As a result, we confirm that there was a difference in the performance of each scheme according to the actual 3D terrain and that the location-based FRP that considers deployment errors, has the highest efficiency in many aspects.

Bilateral iliac and popliteal arterial thrombosis in a child with focal segmental glomerulosclerosis

  • Han, Kyoung Hee;Park, Ji Youn;Min, Seung-Kee;Ha, Il-Soo;Cheong, Hae Il;Kang, Hee Gyung
    • Clinical and Experimental Pediatrics
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    • v.59 no.5
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    • pp.242-245
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    • 2016
  • Thromboembolic complications (TECs) are clinically important sequelae of nephrotic syndrome (NS). The incidence of TECs in children is approximately 2%-5%. The veins are the most commonly affected sites, particularly the deep veins in the legs, the inferior vena cava, the superior vena cava, and the renal veins. Arterial thrombosis, which is less common, typically occurs in the cerebral, pulmonary, and femoral arteries, and is associated with the use of steroids and diuretics. Popliteal artery thrombosis in children has been described in cases of traumatic dissection, osteochondroma, Mycoplasma pneumoniae infection, and fibromuscular dysplasia. We report of a 33-month-old girl with bilateral iliac and popliteal arterial thrombosis associated with steroid-resistant NS due to focal segmental glomerulosclerosis. Her treatment involved thrombectomy and intravenous heparinization, followed by oral warfarin for 8 months. Herein, we report a rare case of spontaneous iliac and popliteal arterial thrombosis in a young child with NS.

Development of Leuconostoc sp. Host Vector System

  • Eom, Hyun-Ju;Park, Myeong-Soo;Ji, Geun-Eog;Han, Nam-Soo
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2004.06a
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    • pp.323-327
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    • 2004
  • Leuconostoc citreum CBUE isolated from kimchi proved to harbor a small cryptic plasmid, pNS75. The complete nucleotide sequence of pNS75 was 1,821 bp and had a low G+C content of 39.2%. Computer analysis using DNASIS revealed one open reading frame (ORF), having ATG as putatitive start condon and potentially encoding proteins with molecular mass of 38 kDa. The chimeric plasmid pLeuCM was first constructed wih pNS75, pUC19 and chroamphenicol acetyltransferase (CAT) from Staphylococcus sp.. pLeuCM replicated and expressed chroamphenicol acetyltransferase in Leuconostoc citerum CBNF after transformation. To test the availability of shuttle vector as cloning vehicle of foreign gene, $\alpha$-amylase gene of Streptococcus bovis was cloned and all transformants secreated the $\alpha$-amylase successfully. The result indicates that pLeuCM is a potential shuttle vector for Leuconostoc spp. and lactic acid bacteria.

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