• Title/Summary/Keyword: LR2

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Design of Time Synchronizer for Advanced LR-WPAN Systems (개선된 LR-WPAN 시스템을 위한 시간 동기부 설계)

  • Park, Mincheol;Lee, Dongchan;Jang, Soohyun;Jung, Yunho
    • Journal of Advanced Navigation Technology
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    • v.18 no.5
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    • pp.476-482
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    • 2014
  • Recently, with the growth of various sensor applications, the need of wireless communication systems which can support variable data rate is increasing. IEEE 802.15.4 LR-WPAN system using 2.45 GHz frequency band is very popular for the sensor applications. However, since LR-WPAN only supports the data rate of 250 kbps, it has a limit to be applied to various sensor networks. Therefore, we define the preamble structure which can support the data rates of 31.25 kbps, 62.5 kbps, 125 kbps, and present the low-complexity hardware architecture for time synchronizer based on double-correlation algorithm which can resist the CFO (carrier frequency offset). Implementation results show that the proposed time synchronizer include the logic slice of 18.36 K and four DSP48s, which are reduced at the rate of 79.1% and 99.4%, respectively, compared with existing architecture.

Adaptive Beacon Scheduling Algorithm to Reduce End-to-End Delay in Cluster-tree based LR-WPAN (클러스터-트리 기반 LR-WPAN에서 End-to-End 지연시간을 줄이기 위한 적응적 Beacon 스케줄링 알고리즘)

  • Kang, Jae-Eun;Park, Hak-Rae;Lee, Jong-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.3B
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    • pp.255-263
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    • 2009
  • In this paper, we propose an adaptive beacon scheduling algorithm to control a reception period of actual data according to variation of amount of traffic in IEEE 802.15.4 LR-WPAN(Low Rate-Wireless Personal Area Network) with the cluster-tree topology. If a beacon interval is shortened, the amount of the traffic a node receives can be increased while consumption of the energy can be also increased. In this sense, we can achieve optimal on orgy consumption by controlling the beacon interval when the amount of data to be received is being decreased. The result of simulation using NS-2 shows that the proposed algorithm improves performances in terms of packet loss rate and end-to-end delay compared with algorithm using a fixed beacon interval. For a design of cluster-tree based LR-WPAN managing delay-sensitive services, the proposed algorithm and the associated results can be applied usefully.

The Effects of Acupuncture at LR3 Acupoint on Mitochondrial Complex IV Oxidase activity in Liver (태충 침자가 간 미토콘드리아 내 Complex IV에 미치는 영향)

  • Choi, Donghee;Lee, Yumi;Kim, Mirae;Park, Jeonghye;Kim, Hyeran;Na, Changsu;Youn, Daehwan
    • Korean Journal of Acupuncture
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    • v.36 no.4
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    • pp.200-209
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    • 2019
  • Objectives : The liver is rich in mitochondria and it plays a key role in whole-body energy homeostasis. Mitochondria is double membrane-bound organelle that supplies energy for intracellular metabolism including Krebs cycle and beta-oxidation. Acupuncture is known to stimulate and regulate the flow of energy. To explore the effect of acupuncture on the mitochondrial respiratory chain activity in the rats' livers, the activity of mitochondrial respiratory chain complexes I to IV was observed. Methods : The rats were divided into 4 groups; Normal 1 (no acupuncture treatment and anesthesia for 5 min), Normal 2 (no acupuncture treatment and anesthesia for 10 min), MA1 (acupuncture treatment at bilateral LR3 under anesthesia for 5 min), and MA2 (acupuncture treatment at bilateral LR3 under anesthesia for 10 min). All rats were sacrificed and the livers were examined for respiratory chain change. Results : There was no difference in ubiquinon oxidoreductase, succinate dehydrogenase, and ubiquinol cytochrome C oxidoreductase after acupuncture at LR3. Acupuncture at LR3 for 10 min increased the activity of cytochrome C oxidase compared with no acupuncture groups. Conclusions : Acupuncture at LR3 mediated mitochondrial respiratory chain activity via the cytochrome C oxidase signaling pathway in the livers of rats.

Effect of Acupuncture and Electro-acupuncture at $LR_3$ on Intestinal Motility in Rats (태충 유침 및 전침이 병태모델 흰쥐의 장운동에 미치는 영향)

  • Lim, Sung-Chul;Lee, Hyun
    • Journal of Acupuncture Research
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    • v.25 no.5
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    • pp.27-42
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    • 2008
  • Objectives : The purpose of this study was to observe the effects of acupuncture and electro-acupuncture at $LR_3$ on intestinal motility in rat. Methods : We made over-activated state of intestinal motility with carbachol and suppressed state of intestinal motility with loperamide in rat and carried out needle retention acupuncture and high frequency electro-acupuncture at $LR_3$ in rat devided into pre-treatment group and post-treatment group. The charcoal travel rate was measured to evaluate the intestinal motility. Results : 1. High frequency electro-acupuncture at $LR_3$ have significant influences on intestinal motility of rat in normal state. 2. Pre-treatment of needle retention acupuncture, high frequency electro-acupuncture significantly decreased intestinal motility in rat which over-activated with carbachol. 3. Post-treatment of high frequency electro-acupuncture significantly increased intestinal motility in rat which suppressed with loperamide. Conclusions : These results suggest that acupuncture and electro-acupuncture at $LR_3$ are effective on intestinal motility in rat.

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The Effect of LR3 Acupuncture on Blood Pressure and C-fos Expression in Hypertensive Rats Induced by 2K1C (침자(鍼刺)가 혈압(血壓) 및 신경계(神經系) 혈압중추(血壓中樞) c-fos 발현에 미치는 영향(影響))

  • Kang Dong-Hwan;Yun Yeo-Chung;Kim Jeong-Sang;Kim Won-Jae;Na Chang-Su
    • Korean Journal of Acupuncture
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    • v.19 no.1
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    • pp.47-56
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    • 2002
  • The frequency of the hypertension is increasing as the life level is improved and an average span of the life is extended since we approached modern stage. The hypertension is also dangerous disease which raises fatal complication for example with the bleeding aproplexy and the ischemic attack. The medicinal treatment about the hypertension is required patients to take continually. The acupuncture have been introduced because a medicine-chemical treatment hasn't good influence on the human body. It recently has been processed that studies acupuncture effect for blood pressure and have been found out that blood pressure go down. The object of this study observe the effect of LR3 acupuncture on hypertension in Renal Hypertension RAT induced by 2K1C. The 2K1C model was based on renin-angiotensin system. We put the silver clip in renal artery to induce renal hypertension. We try to observe that LR3 acupuncture influence on the blood pressure and c-fos expression in CVLM, NTS, RVLM. In results, the blood pressure was decreased during acupuncture than before acupuncture, after acupuncture. The heart rate was also decreased during acupuncture than before acupuncture, after acupuncture. The LR3 acupuncture significantly effects on blood pressure and heart rate (P<0.05). The increased expression of c-fos was shown in CVLM, NTS, but not in RVLM. In conclusion, LR3 was relived the action of control upon the hypertension and related with medulla, particularly CVLM, NTS. It needs to be closely examined pharmacological mechanism and studied combination with other acupoints.

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Plastochron indices for leaf development of glycine max (Glycine max 잎의 성장 분석을 위한 Plastochron 에 관한 연구)

  • Kim, Jong-Hee
    • The Korean Journal of Ecology
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    • v.15 no.1
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    • pp.1-7
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    • 1992
  • The dvelopment of leaves in soybean(glycine max cv. yellow grain and glycine max cv. black grain)plant were assessed for the applicability of the plastochron index. The plastochron ages versus time in days were respectively 6.4 days in black grain and 9.6 days in yellow grain. Plots of plastochron indes(pi) versus time were linear, there were two distinct groups of regression line. when a point of intersection in the lines were upper than the reference length, pi was estimated n+(ln Ln-ln LR)/(ln Ln-ln Ln+2) or (n-1)+(ln Ln-1-ln LR)/(ln Ln-1-ln Ln+1) . When a point of intersection in the lines were less than the reference length, pl was estimated n+(ln Ln-ln LR)/(ln Ln-ln Ln+2) or (n-1)+(ln Ln-1-ln LR)/(ln Ln-1-ln Ln+1) . The growth rate of black grain plants analysed by pl was higher than yellow grain plants.

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A study on Brain activity induced by electro-acupuncture on Taechung(LR3) and Hapkok(LI4) using functional Magnetic Resonance Imaging (태충(太衝)(LR3).합곡(合谷)(LI4) 전침자극(電鍼刺戟)이 뇌활성(腦活性) 변화(變化)에 미치는 영향(影響) - fMRI를 이용(利用)한 연구(硏究) -)

  • Park, Tae-Gyoon;Kim, Young-Il;Hong, Kwon-Eui;Yim, Yun-Kyoung;Lee, Hyun;Lee, Byung-Ryul
    • Korean Journal of Acupuncture
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    • v.21 no.2
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    • pp.29-46
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    • 2004
  • Objectives and Methods : This study was performed to investigate the effect of electro -acupuncture at four gates(bilateral LR3 and LI4) on brain activity in normal subjects using fMRI. Results and Conclusions : 1. fMRI signal increase by electro-acupuncture at Lt. LR3 was observed in Rt. Middle frontal gyrus in group average as well as more than half of the subjects. 2. fMRI signal decreases by electro-acupuncture at Lt. LR3 were observed in Rt. Superior frontal gyrus, Rt. Middle temporal gyrus, Rt. Cingulate gyrus in group average as well as more than half of the subjects. 3. fMRI signal increases by electro-acupuncture at Lt. LI4 were observed in Lt. Superior frontal gyrus, Lt. Middle frontal gyrus, Lt. Inf. Semi-Lunar Lobule(cerebellum), Rt. Middle frontal gyrus, Rt. Cingulate gyrus in group average as well as more than half of the subjects. 4. fMRI signal decreases by electro-acupuncture at Lt. LI4 were observed in Lt. Middle frontal gyrus, Lt. Inferior frontal gyrus, Lt. Precentral gyrus and Rt. Middle frontal gyrus, Rt. Middle temporal gyrus, Rt. Precuneus, Rt. Inferior frontal gyrus, Rt. Postcentral gyrus in group average as well as more than half of the subjects. 5. fMRI signal increase by electro-acupuncture at Lt. LR3 and Lt. LI4 in group average as well as more than half of the subjects was not observed. 6. fMRI signal decreases by electro-acupuncture at Lt. LR3 and Lt. LI4 were observed in Lt. culmen(cerebellum), Lt. Cingulate gyrus와 Rt. Middle frontal gyrus, Rt. Cingulate gyrus, Rt. Inferior frontal gyrus in group average as well as more than half of the subjects. 7. fMRI signal increases by electro-acupuncture at four gates (bilateral LR3 and LI4) were observed in Lt. Middle temporal gyrus and Lt. Postcentral gyrus in group average as well as more than half of the subjects. 8. fMRI signal decrease by electro-acupuncture at four gates (bilateral LR3 and LI4) were observed in Lt. Middle frontal gyrus, Lt. Precentral gyrus, Lt. Inferior frontal gyrus, Lt. Middle temporal gyrus, Lt. Frontal sub-gyral and Rt. Tuber(cerebellum) in group average as well as more than half of the subjects.

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Comparison of Landslide Susceptibility Analysis Considering the Characteristics of Landslide Trigger Points (산사태 발생지점의 특성을 고려한 취약성 분석 비교)

  • Shin, Hyun Woo;Lee, Su Gon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.2
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    • pp.59-66
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    • 2018
  • This study examined the correlation among topography, forest type, soil and geology in Inje area where landslides occurred during heavy rainfall from July 11 to July 18, 2006 to assess the landslide susceptibility. In order to assess the susceptibility of future landslides, landslides occurred in Inje area were classified into slide type and flow type, and slope angle, aspect, curvature, ridge and valley were extracted from the area. The landslide susceptibility was assessed by applying diameter class, age class, density, and forest type to Bayesianbased LR (Logistic Regression) model and WOE (Weight of Evidence) model, and the fitness of modeling was verified by predict rate curve. As the results of susceptibility assessment, using all landslides without no distintion, it was found that 75% of the LR model and 73% of the WOE model were fit in terms of the top 20% of the landslides. According to slide type and flow type in the top 20% of the landslides, it was found that 71% of the LR model and 69% of the WOE model were fit in terms of the slide type. Whereas, it was found that 86% of the LR model and 82% of the WOE model were fit in terms of the flow type. That is, the results of the LR model showed higher fitness than the results of the WOE model, and the fitness of the flow type was higher than that of the slide type. Consequently, it suggests that it is reasonable to assess and verify the landslide susceptibility according to the types of landslides.

The Hemodynamic Effects of Acupuncture on Taechung($LR_3$) on Mammary Tissues of Rat Monitored by Diffuse Optical Imaging (Diffuse Optical Imaging으로 측정한 태충($LR_3$) 자침이 쥐의 유방 조직에 미치는 혈역학적 변화)

  • Cho, Myeong-Rae;Kim, Jae-Gwan
    • Journal of Acupuncture Research
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    • v.27 no.6
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    • pp.59-66
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    • 2010
  • 목적 : 태충($LR_3$)에 자침을 하는 것이 쥐의 유방 조직에 미치는 혈역학적 변화를 측정하기 위하여 diffuse optical imaging 기법을 사용하였다. 방법 : 실험에 사용한 쥐는 자침을 하지 않은 대조군 7마리, 태충에 자침을 한 실험군 8마리로 총 2개의 군으로 나누었다. 몸무게 170g 정도의 건강한 암컷 쥐는 100% 산소와 1.5% isoflurane을 혼합한 것을 이용하여 마취시켰다. 자침은 양 발등의 첫째와 둘째 중족골 사이의 지점인 태충($LR_3$)에 20분간 시행하였다. Beckman Laser Institute and Medical Clinic에서 개발된 modulated imaging system을 이용하여 자침하기 전과 자침하고 있는 동안에 산화혈색소(OHb), 탈산소혈색소(RHb), 총 혈색소(THb)와 조직 산소 포화도($StO_2$)의 영상을 얻었다. 결과 : 실험 결과 태충($LR_3$)에 자침을 한 실험군에서는 대조군에 비하여 유의성이 있는 OHb THb의 감소와 유의성이 없는 RHb의 증가가 나타났다. 결론 : Diffuse optical imaging 기법으로 자침 중에 조직 산소공급과 혈류량의 변화를 확인할 수 있었고, 이는 비침습적으로 자침의 효과를 측정하는 데 활용할 수 있다고 생각한다. 또한 자침으로 인한 유방조직의 혈역학적 조절은 암 검진뿐만 아니라 암 치료에도 다른 치료와 병행하여 활용할 수 있으리라 생각한다.

Advantages of Laparoscopic Abdominoperineal Resection for Anastomotic Recurrence of Rectal Cancer

  • Zhang, Xing-Mao;Wang, Zheng;Ma, Sheng-Hui;Zhou, Zhi-Xiang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4295-4299
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    • 2014
  • Background: Surgery offers the only potential for cure and long-term survival of recurrence of rectal cancer. Few studies about laparoscopic recurrent lesion resection have been reported. This study was designed to evaluate the safety and feasibility of laparoscopic abdomino-perineal resection for anastomotic recurrence of rectal cancer. Materials and Methods: Data for 42 patients with recurrence of rectal cancer were collected retrospectively. Of the 42 patients, 22 underwent laparoscopic surgery (LR group) and 20 received open surgery (OR group). Outcomes between the two groups were compared. Results: Operation time in LR group was shorter compared with the OR group ($164.6{\pm}27.7min$ vs $203.0{\pm}45.3min$); intra-operative blood loss was $119.7{\pm}44.4ml$ and $185.0{\cdot}94.0ml$ in LR group and OR group, respectively (p<0.001); time to first flatus in LR group was shorter than in OR group, and the difference was statistically significant ($2.6{\pm}0.8$ days vs $3.1{\pm}0.8$ days, p=0.013); hospital stay in the LR and OR groups was $8.6{\pm}1.3$ days and $9.8{\pm}2.2$ days; 3-year survival rates in the LR and OR groups were 44.4% and 42.8% (p=0.915) and the 3-year disease-free survival rates were 36.4% and 30.0%, respectively (p=0.737). Conclusions: Laparoscopic abdomino-perineal resection is safe and feasible for anastomotic recurrence of rectal cancer.