• Korean Journal of Acupuncture
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• 제26권2호
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• pp.91-108
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• 2009

Objectives: Single colorectal instillation of trinitrobenzenesulphonic acid (TNBS) causes a dose-dependent increase of visceral motor response (VMR) and severity of inflammation. In this study we compared the effects of electroacupuncture in the different acupoints in the acute colitis induced by TNBS intracolonic injection in rats. Methods: In Male Sprague-Dawley rats, weighing $250{\sim}400g$, a single colorectal administration of TNBS 5mg/kg and 50% ethanol under isoflurane anaesthesia after an overnight fast. Electrodes for electromyography (EMG) recording were stitched into the external oblique musculature under general anesthesia. Acupoints of LI4, ST25, or ST36 were stimulated by electroacupuncture, respectively. The balloon was inserted intra-anally and visceral motor response (VMR) to colorectal distensioin (CRD) was quantified with an EMG recording system. Results: At an observation of the visceral hyperalgesia in the day-time series, the visceromotor response increased significantly 3 days after TNBS intra-rectalcolonic injection in rats. Electroacupuncture on either ST25 or ST36 suppressed the visceromotor response to colorectal distension, but not LI4, at 3 days after TNBS injection. Pretreatment of naltrexone (10 mg/kg, i.p.), opioids antagonist, inhibited the VMR suppress of 10Hz EA to ST36 but not phentolamine (5 mg/kg, i.p.). Pretreatment of either naltrexone or phentolamine inhibited effects of 10Hz EA to ST25. Conclusions: Data show that EA at either ST25 or ST36 potently inhibits hypersensitivity of colorectum after TNBS induced colitis and is differently mediated through the endogenous opioid system and adrenergic system.

• 한국ITS학회 논문지
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• 제19권6호
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• pp.74-87
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• 2020

과적차량은 도로 주행환경의 안전을 위협하고 도로구조물의 수명단축에 직접적인 영향을 주는 주요 원인이다. 자중계는 화물차량에 탑재하여 중량을 측정할 수 있는 유일한 장비로, 운전자는 스스로 과적상태를 확인하고 운행 전 상차 시 적재중량을 조절하여 과적을 사전에 예방할 수 있다. 본 연구에서는 과적 적재물 중 골재 및 토사가 전체의 36.55%로 주요 과적적재물로 나타나 이를 주로 운송하는 30대의 건설폐기물 수집·운반차량을 선정하였으며, 자중계의 시범설치 및 원격 모니터링을 수행하여 운행데이터를 수집하였다. 운전자에게 중량을 인지할 수 있는 중량표시 앱을 배포하기 전 1달과 배포한 후 1달 동안 운행데이터를 비교하여 과적 예방효과를 분석하였다. 자중계로부터 제공받은 적재중량을 인지함으로써 과적운행이 6.1%가 감소한 것을 확인하였으며, 운송량을 극대화하면서 단속을 우려하여 원거리로 우회 주행을 할 필요가 없어 운송거리와 시간이 줄어 운송 효율이 높아진 것을 확인하였다.

• 항공우주시스템공학회지
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• 제18권2호
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• pp.64-70
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• 2024

국내에서 중형급 무인동력비행장치(25kg < MTOW ≤ 150kg) 신고 건수 및 안전성인증 수요가 급격하게 증가하고 있다. 그리고 무인동력비행장치 안전성인증 불합격 사례도 증가하고 있으며, 제작 품질 문제가 불합격의 주요 원인으로 확인되고 있다. 그러나 무인동력비행장치 안전성인증 제도에서 제작업체에 대한 품질시스템 기준은 부재하다. 따라서 본 논문에서는 무인동력비행장치 제작업체의 품질시스템 점검 기준을 수립하기 위해 국내 안전성인증 업무와 미국재료시험협회(ASTM)의 소형 무인항공시스템(sUAS)의 품질 기준을 분석하였다. 그리고 국내 제작사 실정에 맞는 품질시스템 기준 수립을 위해 중형급 무인동력비행장치 제작업체 현장실사를 통해 제작 품질시스템 특성을 추가 점검항목으로 반영한 제작업체 품질시스템 기준을 제안하였다. 그리고 제안된 품질시스템 기준에 대하여 국내 무인동력장치 제작업체 7개사를 대상으로 설문조사를 수행하였다.

• IMMUNE NETWORK
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• 제2권2호
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• pp.109-114
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• 2002

Background: To investigate the role of sympathetic nervous system (SNS) in moxibustion-induced immunomodulation, the effects of chemical sympathectomy on moxibustion-induced changes in splenic NK cell cytotoxicity, T and B cell proliferation were studied in Sprague-Dawley male rats. Methods: Chemical sympathectomy was achieved with intraperitoneal injection of 6-hydroxydopamine 50 mg/kg/day for 3 successive days. Direct moxibustion (6-minute interval, 9 moxa ball, each of which weighing 0.007 g and burning for 40 seconds) was applied on unilateral anterior tibial muscle region where Zusanli (ST36) acupoint is located, once a day for 7 successive days. NK cell cytotoxicity was measured by $4hr-^{51}Cr$ release assay. Mitogen-induced lymphocyte proliferation was analyzed by [$^3H$]-thymidine incorporation assay. Results: NK cell cytotoxicity was suppressed by moxibustion, more in sympathectomized rats than in vehicle-treated rats. T cell proliferation induced by concanavalin A was not affected by moxibustion. B cell proliferation induced by lipopolysaccharide showed no significant change in vehicle-treated rats, but an increase in sympathectomized rats by moxibustion. Sympathectomy alone induced augmentation of NK cell cytotoxicity and suppression of T cell proliferation. Conclusion: These results suggest that SNS has no direct relation with moxibution-induced immunomodulation but has an important role in the mechanism to keep the homeostasis of immune system by tonically inhibiting excessive changes of various immune components.

• 대한전자공학회논문지SP
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• 제42권1호
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• pp.71-77
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• 2005

본 논문에서는 5.1채널 입체음향 오디오 신호를 2채널의 헤드폰으로 재생하기 위한 HRTF (Head Related Transfer Function) 기반의 입체음향 생성 시스템에 대하여 다룬다. 각 채널의 모노 입력신호는 HRTF를 이용한 바이노럴(binaural) 필터링을 통해 가상적으로 음상정위되며, 입체감과 공간감을 증가시키기 위해 잔향효과가 추가된다. 연산량 감소를 위해 음상정위 성능을 저하시키지 않는 범위에서 HRTF의 임펄스 응답 탭 수를 줄였으며, 잔향효과를 위한 음장제어부에서는 초기반사열중 주요한 성분만을 지연기로 모델링하였다. 또한 비개인화된 HRTF DB에 의란 앞/뒤 혼돈 문제를 줄이기 위하여 앞/뒤 스펙트럼의 차를 가중치로 하여 HRTF 스펙트럼을 강조하는 방법을 적용하였다. 구현한 시스템의 성능 평가 결과, 단순한 스테레오 방법이나 2채널 Down Mixing 방식에 비해 현실감 있고 방향성 있는 입체음향을 느낄 수가 있었다.

• 한국동물위생학회지
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• 제40권4호
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• pp.287-292
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• 2017

A five-year-old, male, Great Dane weighing 107 kg was presented with anorexia, abdominal distension, and dyspnea for 5 days. Physical examination, blood works, radiography, electrocardiography (ECG), and echocardiography were performed. Based on severely low fractional shortening (FS) and marked four chamber enlargement in echocardiography, continuous atrial fibrillation and occasional ventricular premature complex (VPC) on ECG, the dog was diagnosed as dilated cardiomyopathy (DCM) concurrent with congestive heart failure. Pleural effusion and ascites were modified transudate. In accordance with DCM scoring system recommended by European Society of Veterinary Cardiology (ESVC), DCM score was 13/15 in this case. Concentrations of cTnI and NT-pro-BNP were 1.0 ng/mL and 693 pmol/L, respectively. Since the former and the latter were remarkably high values, it was certain that the patient had grave prognosis. Intensive care was performed for the dog and the clinical signs as well as the radiographic abnormalities were resolved. However, when he presented serious dyspnea again at 25 days post therapy, the dog was dead. In case of canine DCM, the scoring system for the diagnosis and cardiac biomarkers including NT-pro-BNP and cTnI could be useful to advise owners on the status and prognosis of their dog with DCM.

• Structural Engineering and Mechanics
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• 제43권5호
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• pp.607-621
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• 2012

The Expo Culture Centre is one of the permanent buildings at the World Expo 2010 in Shanghai, China. The main structure has an oval shape and consists of 36 radial cantilever steel trusses with different lengths and inner frames made of concrete-filled rectangular steel tube members. Tuned mass dampers are used to reduce the excessive vibrations of the sixth floor that are caused by human-induced resonance. A three-dimensional analytical model of the system is developed, and its main characteristics are established. A series of field tests are performed on the structure, and the test results show that the vertical vibration frequencies of most structural cantilevers are between 2.5 Hz and 3.5 Hz, which falls in the range of human-induced vibration. Twelve pairs of tuned mass dampers weighing 115 tons total were installed in the structure to suppress the vibration response of the system. These mass dampers were tuned to the vertical vibration frequency of the structure, which had the highest possibility of excitation. Test data obtained after the installation of the tuned mass dampers are used to evaluate their effectiveness for the reduction of the vibration acceleration. An analytical model of the structure is calibrated according to the measured dynamic characteristics. An analysis of the modified model is performed and the results show that when people walk normally, the structural vibration was low and the tuned mass dampers have no effect, but when people run at the structural vibration frequency, the tuned mass dampers can reduce the floor vibration acceleration by approximately 15%.

• Smart Structures and Systems
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• 제6권3호
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• pp.277-290
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• 2010

Internationally the load carrying capacity of bridges is decreasing due to material deterioration while at the same time increasing live loads mean that they are often exposed to stresses for which they were not designed. However there are limited resources available to ensure that these bridges are fit for purpose, meaning that new approaches to bridge maintenance are required that optimize both their service lives as well as maintenance costs. Wireless sensor networks (WSNs) provide a tool that could support such an optimized maintenance program. In many situations WSNs have advantages over conventional wired monitoring systems in terms of installation time and cost. In order to evaluate the potential of these systems two WSNs were installed starting in July 2007 on the Humber Bridge and on a nearby approach bridge. As part of a corrosion prevention strategy, a relative humidity and temperature monitoring system was installed in the north anchorage chambers of the main suspension bridge where the main cables of the bridge are anchored into the foundation. This system allows the Bridgemaster to check whether the maximum relative humidity threshold, above which corrosion of the steel wires might occur, is not crossed. A second WSN which monitors aspects of deterioration on a reinforced concrete bridge located on the approach to the main suspension bridge was also installed. Though both systems have provided useful data to the owners, there are still challenges that must be overcome in terms of monitoring corrosion of steel, measuring live loading and data management before WSNs can become an effective tool for bridge managers.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.128-131
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• 2005

The effects of alternate-week feeding strategies on growth and feed efficiency ratio of juvenile Nile tilapia were investigated in a recirculating aquaculture system. Twenty fish initially weighing 25.5 g were randomly distributed into each of 18 tanks to conduct three replicates for each of six different feeding strategies. Weight gain of fish in the control that were fed daily for 6-week feeding trial was significantly higher than those of fish subjected to various alternate-week feeding regimes. Weight gain of fish that were starved for 3 weeks and then fed daily for 3 weeks (3WS+3WF) was not significantly different from that of fish, starved and fed daily for alternate 1-week period during the trial (1WS+1WF), but was significantly higher than those of fish starved for 2 weeks, and fed for 2 weeks (2WS+2WF); fish starved for 4 weeks and fed for 2 weeks (4WS+2WF); and fish fed for 5 weeks and fed for 1 week (5WS+1WF.) The amount of feed supplied to fish in the groups of 1WS+1WF and 3WS+3WF was significantly lower than that fed to fish in the control group, but significantly higher than the amount feed supplied to fish in the other three groups. Feed efficiency ratio for fish in the control group did not differ from that for fish in the groups of 1WS+1WF, 2WS+2WF and 3WS+3WF, but was significantly higher than that for fish in the groups of 4WS+2WF and 5WS+1WF. In conclusion, juvenile Nile tilapia that were subject to starvation for 1 to 5 weeks did not exhibit compensatory growth sufficient to attain the same weight as fish fed daily for 6 weeks. In addition, fish subjected to starvation exhibited low feed efficiency ratio compared to fish fed daily, which were probably attributable to poor weight gain.

• Preventive Nutrition and Food Science
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• 제9권4호
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• pp.352-360
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• 2004

To investigate the antioxidative effects of an etbylacetate fraction extracted from the flowers of Chrysanthemum indicum L. (Chrysanthemi Flos) on the antioxidative system and lipid profiles of rats with ethanol induced hepatotoxicity. Sprague-Dawley rats weighing $100\~150$ g were divided into 5 groups: normal group (NOR), Chrysanthemi Flos EtOAC fraction (200 mg/kg) treated group (S1), $35\%$ etbanol (10 mL/kg) treated group (S2), Chrysanthemi Flos EtOAC fraction (200 mg/kg) and ethanol concomitantly treated group (S3) and Chrysanthemi Flos EtOAC fraction (400 mg/kg) and ethanol concomitantly treated group (S4), respectively. The antioxidative activity of each fraction was decreased in order of EtOAC, n-hexane, n-BuOH, water and chloroform. The growth rates and feed efficiency ratios were decreased by ethanol treatment, but were gradually restored to similar levels as in the NOR group by administering Chrysanthemi Flos EtOAC fraction. The whole blood concentrations of total cholesterol and LDL-cholesterol, and the activities of ALT and AST that were elevated by ethanol were significantly decreased in the Chrysanthemi Flos EtOAC fraction treated groups. It was also observed that the activities of SOD, catalase, xanthine oxidase and GSH-Px elevated by ethanol in rat liver were markedly decreased in the Chrysanthemi Flos EtOAC fraction treated group as compared to S2. These results suggest that Chrysanthemi Flos EtOAC fraction has possible protective effects against ethanol induced hepatotoxicity in rat liver.