• Title/Summary/Keyword: captive

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Store Separation Analysis of Flow Angularity Wind Tunnel Test Technique using CFD (1) (CFD를 활용한 Flow Angularity 풍동시험기법의 외장분리 해석(1))

  • Son, Chang-Hyeon;Seo, Sung-Eun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.1
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    • pp.10-20
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    • 2017
  • This study presents the feasibility of CFD(computational fluid dynamic) analysis using the flow angularity wind tunnel test technique. The CFD analyzed data by the flow angularity technique has been constructed as the database to get store trajectories by 6-DOF simulation. The database has been checked out store aerodynamic coefficients by the analyses at each position under wing. After that process, the simulated trajectories by database have been compared with the store trajectories by CTS(Captive Trajectory Simulation) of CFD. The trajectories provided by the database of flow angularity have a good agreement with the store trajectories by CFD.

Study of a Characteristics of Maneuvering Mathematical Model of Twin POD Cruise Ship (2축 POD 여객선의 조종운동 수학모형 특성 연구)

  • Kim, Yeon-Gyu;Yun, Kun-Hang;Kim, Sun-Young;Son, Nam-Sun
    • Journal of the Society of Naval Architects of Korea
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    • v.50 no.6
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    • pp.429-435
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    • 2013
  • Recently, to improve the safety and maneuverability at fairway around harbor the POD system has been equipped on a ship. And the interest about maneuvering characteristics of a cruise ship has been increasing. In this paper the mathematical model of maneuvering motion of a cruise ship with twin POD system in general speed and slow speed are presented. And the maneuvering coefficients of mathematical model are obtained from the captive model tests using CPMC(Computerized Planar Motion Carriage). Computer simulation using mathematical model in general speed and slow speed are carried out and compared with the results of free running model test with the same model ship. The differences between the mathematical models are compared and discussed. In this paper the mathematical models, the results of captive model test and simulation results are presented.

Prediction of Maneuverability of KCS with 4 Degrees of Freedom (KCS 선형의 4자유도 조종성능 추정)

  • Kim, Yeon-Gyu;Yeo, Dong-Jin;Son, Nam-Sun;Kim, Sun-Young;Yun, Kun-Hang;Oh, Byeong-Ik
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.3
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    • pp.267-274
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    • 2011
  • This paper presents the results of prediction of maneuverability of KCS about 4 degree of freedom(DOF) including roll motion. The prediction is carried out by CPMC captive model test. The CPMC(Computerized Planar Motion Carriage) with captive model test equipment including roll moment gage is installed at Ocean Engineering Tank of MOERI. KCS is the container ship open to the world by MOERI. To predict the 4 DOF maneuverability of a ship some tests with roll angle are conducted. And the prediction results of maneuverability by simulation are compared with the results of free running model test. The simulation results agree well with those of free running model tests.

Necrotic enteritis in a captive mute swan (Cygnus olor) in the breeding season

  • Lee, Hae Rim;Koo, Bon-Sang;Jeon, Eun-Ok;Han, Moo-Sung;Min, Kyung-Cheol;Lee, Seung Baek;Bae, Yeonji;Kim, Jung-Ho;Mo, In-Pil
    • Korean Journal of Veterinary Service
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    • v.37 no.2
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    • pp.137-141
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    • 2014
  • A captive mute swan (Cygnus olor) in the brooding period was found dead without any specific signs. On necropsy, the entire digestive tract was severely necrotized with loosely adherent pseudomembranes, and Clostridium perfringens (CP) colonies isolated from the intestinal contents were identified as CP type A by polymerase chain reaction. Microscopically, the intestine and the liver were necrotized and intralesional bacterial clusters were observed. In this case, there were no other mortalities, so the condition of a single bird, in particular, stress from incubation effort, could act as the predisposing factor for necrotic enteritis. In this study, we report a unique case of necrotic enteritis associated with incubation in a captive mute swan.

Captive Flight Test System Configuration and Verification for Multi-mode Guidance Missile System (복합유도방식이 적용된 유도탄의 탑재비행시험(CFT) 시스템 구성 및 검증)

  • Park, Inchul;Heo, Wonyoung;Lee, Yongho;Jeong, Seyoung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.5
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    • pp.606-612
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    • 2016
  • A Captive Flight Test(CFT) is used to verify the performance of missile component such as seeker and guiding algorithm of missile. Recently most of surface to air missile adapts multi-mode guidance method which include command guidance and active/passive guidance. A CFT system for missile system adapting multi-mode guidance method consists of pod equipment, command transmitting system and measuring system. In this paper, we proposed CFT system and testing method for missile which adapt multi-mode guidance, and system integration procedure by using distributed missile system integration method and procedure. The proposed CFT system and system integration method was applied to CFT of surface to air missile, and brought successful result.

A Study on Development of Wireless Check-up Device for Captive Flight Test (탑재비행시험용 무선 점검장치 개발에 대한 연구)

  • Ryu, Sang-Gyu;Joo, Junghyun;Ko, Myoungjun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.22 no.4
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    • pp.501-508
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    • 2019
  • In this paper, a study on a wireless check-up method of test equipment for captive flight test(CFT) was conducted. For CFT, test equipment is mounted on a POD, and check-up is carried on the test equipment's. For check-up the POD wirelessly, battery, power distribution unit, wireless communication devices were designed within the POD, and a check-up device is designed outside of the POD. Once the external check-up device sends a 'start signal' to the POD, it performs the overall check-up procedures and transmits the 'end signal' to the external check-up device. Detailed check-up results are stored in an internal storage device, and are possible to read from external check-up device if necessary, thereby improving the reliability of the wireless check-up. By implementing and applying these wireless check-up system, the reliability of the check-up was enhanced by dynamical and movable check-up, and safety is guaranteed as the check-up was carried without access to the aircraft.

A Study on the Prediction Model of Unmanned Helicopter Fuel Consumption for the Captive Flight Test (탑재비행시험을 위한 무인헬기 연료 소모량 예측모형 연구)

  • Kim, Jisu
    • The Journal of the Korea Contents Association
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    • v.19 no.7
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    • pp.436-443
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    • 2019
  • The purpose of this paper is to establish a predictive model by analyzing the influence and correlation of factors affecting the fuel consumption of unmanned helicopters in Captive Flight Test. In this study, a four-factor two-level full factorial experiment was designed and tested using the design of experiments, results were analyzed to derive the main effects and interactions of the factors, and the predictive model was established through regression analysis. It is expected that the results from this study contribute to carrying out Captive Flight Test efficiently and the improvement of the test capability of Electronic Testing Range.

Mycobacterium genavense induced mycobacteriosis in an Indian peafowl (Pavo cristatus)

  • Oh, Yeonsu;Lee, Sang-Joon;Tark, Dong-Seob;Cho, Ho-Seong
    • Korean Journal of Veterinary Service
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    • v.44 no.2
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    • pp.119-124
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    • 2021
  • The report describes an avian mycobacteriosis in a captive wild bird. A 7-year-old female Indian peafowl (Pavo cristatus) maintained in a zoo of Korea presented a gradual cachexia and eventually was found dead. At necropsy, severely atrophied pectoral muscles exposing the keel bone were noticed. Yellowish thick nodules in varying sizes were scattered in all lobes of lungs, liver and spleen, suggesting mycobacteriosis. Histopathologically, multifocal to coalescing granulomas surrounded by multinucleated giant cells were observed. Numbers of acid-fast bacilli were revealed in granulomas. Then, a series of molecular diagnostic techniques were followed: a nested PCR, DNA sequencing and bioinformatics analysis. It resulted as Mycobacterium genavense. The identification of M. genavense as an etiological agent suggested that it might serve as a risk factor for other captive wild animals, and for a potential zoonotic risk since M. genavense have been a definite cause of disseminated mycobacterial infection in immunocompromised people. To the authors' knowledge, this is the first report of avian mycobacteriosis with M. genavense in a captive Indian peafowl.

Primary diffuse hepatocellular carcinoma in a captive polar bear (Ursus maritimus)

  • Krisdianti, Krisdianti;Kim, Taeyeon;Aufa, Sulhi;Lee, Sangjoon;Ahn, Sangjin;Cho, Ho-Seong;Oh, Yeonsu
    • Korean Journal of Veterinary Service
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    • v.44 no.4
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    • pp.299-303
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    • 2021
  • A captive male polar bear (Ursus maritimus) was found dead after a long-term anorexia at a Park Zoo in Republic of Korea. At necropsy, the liver lesion was prominent with hepatomegaly carrying a big mass and numerous small nodules in various sizes. The cut surface of the nodules was creamy white, firm, and solid with umbilicated appearance. Histologically, there was proliferation of hepatocellular neoplastic cells arranged in glandular-like (pseudoglandular) pattern and complete loss of hepatocellular arrangement. The immunoreactivity for neoplastic hepatocyte antigens was positive for hepatocyte paraffin 1, and negative for vimentin, cytokeratin 7 and 19, and carcinoembryonic antigen. Based on those diagnostic features, the neoplasia was diagnosed as hepatocellular carcinoma. To the author's knowledge, this is the first case report of hepatocellular carcinoma in the captive polar bear in Republic of Korea.

Change of Predator Recognition Depends on Exposure of Predation Risk Source in Captive Breed Endangered Freshwater Fish, Microphysogobio rapidus (인공증식된 멸종위기종 여울마자의 포식 위험원 노출에 따른 포식자 인지 변화)

  • Moon-Seong Heo;Min-Ho Jang;Ju-Duk Yoon
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.406-413
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    • 2023
  • Captive breeding and reintroduction are crucial strategies for conserving endangered species populations. However, fish raised in predator-free environments, show a lack of recognition of predationrelated stimuli such as chemical and visual signals. It is critical to recognize chemical signals from injured conspecifics, also known as alarm signals, and the order or shape of predators to indicate the spread of predation risk in the habitat. We conducted a laboratory experiment to determine and adjust the optimal exposure period to induce appropriate anti-predator behavior response to different types of stimuli (Chemical, Visual and Chemical+Visual) for the endangered species Microphysogobio rapidus. Our results demonstrate that predator avoidance behavior varies depending on the types of stimuli and the duration of predation risk exposure. First, the results showed captive-breed M. rapidus show lack of response against conspecific alarm signal (Chemical cue) before the predation risk exposure period and tend to increase response over predation risk exposure time. Second, response to predator (visual cue) tend to peak at 48 hours cumulative exposure, but show dramatic decrease after 72 hours cumulative exposure. Finally, response to the mixed cue (Chemical+visual) tend to peak prior to the predation risk exposure period and show reduced response during subsequent exposure periods. This experiment confirms the lack of responsiveness to conspecific alarm signals in captive-bred M. rapidus and the need for an optimal nature behavior enhancement program prior to release of endangered species. Furthermore, responsiveness to predator visual signal peak at 48 hours cumulative exposure, suggest an optimal predation risk exposure period of up to 48 hours.