• Title/Summary/Keyword: captive

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A Study on Technique of Development Test by an Aircraft Captive Flight Test in Weapon System (무기체계의 항공기 탑재비행시험을 통한 개발시험 기법 연구)

  • Yeom, Hyeong-Seop;Oh, Jong-Hoon;Sung, Duck-Yong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.37 no.10
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    • pp.1010-1016
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    • 2009
  • In this paper, we have described an aircraft captive flight test for the development test of weapon systems. We have conducted a captive flight test for the development of core onboard parts and sensors of airborne weapons and guided missiles. We have used KTX-1/XKO-1 aircraft as a platform for the captive flight test. In order to perform a captive flight test, we have made a captive test pod as a shape of external fuel tank in the XKO-1 and have modified XKO-1 aircraft for a system interface. We have taken a development test about all kinds of seekers, navigation & guidance systems, and core part of guided missile through the aircraft captive flight test.

Changing Effect in Aerodynamic Characteristics of a Captive Body Separated from Aircraft (항공기 탑재체의 분리 후 공력 특성 변화 효과)

  • Cho, Hwan-Kee;Lee, Sang-Hyun;Kang, Chi-Hang
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.3
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    • pp.397-404
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    • 2011
  • The aerodynamic characteristics of a separated captive body in flow field around aircraft are studied to observe aerodynamic stability for safe separation from aircraft. Since the captive body separated from aircraft is initially exposed to unsteady flow pattern, the change of aerodynamic forces and moments should be measured to analyze how the flow pattern affects on the captive body at the vicinity of aircraft. Aerodynamic forces and moments of the separated captive body are measured at selected positions along predictable dropping trajectories. The measuring trajectories, generated by the free drop test of the dropping model in the wind tunnel, are consisted of 9 possible lines by free dropped trajectories. Experimental results show that the aerodynamic forces and moments are significantly varied with the distance between the captive body and aircraft. In conclusion, the change of aerodynamic characteristics within flow field around aircraft should be considered to simulate trajectories of the separated captive body from aircraft.

The Analysis of the Growth Model and Performance Factors for the Large IT Service Companies in Korea (대형 IT서비스기업의 경영성과 요인 분석 및 성장모델)

  • Kang, Un-Sik;Kim, Hyun-Soo;Ahn, Yeon-S.
    • Journal of Information Technology Services
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    • v.9 no.1
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    • pp.57-71
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    • 2010
  • The purpose of this study is to verify the competence level of IT service companies in Korea from the view point of capability of creating customers value and outcome as an independent companies which have been growing in the captive customers(market) circumstance by performance data analysis and IT specialists survey. This study presents a growth model which emphasis on the importance of the correlation between IT service companies and captive customers. It proves that the captive customers have been being the growth power and motive of the IT service company, because IT service companies have been cumulating the competence for IT service through the service for the customers, and with this competence, IT service companies have been expanding its service out to non-captive market(customers) and got good outcomes as an independent companies. And this study proves that the captive customers who served by the IT service companies which have a higher level of service capabilities have better business outcome. IT service companies contribute to improve the IT level of the captive customers and to make the customers to increase sales by conducting IT projects.

Development and Verification of Wireless Check-up System of POD for Captive Flight Test (탑재비행시험용 POD 무선 점검 시스템 개발 및 검증)

  • Ko, Myoungjun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.2
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    • pp.204-210
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    • 2021
  • In this paper, we studied a method of wirelessly checking up the POD for captive flight tests which is performed during the development of guided weapons systems. The wireless power transfer module, the power distribution device, and the battery pack were designed to wirelessly power the captive flight test POD, and the communication device was designed to enable wireless communication between the POD and the check-up device. The communication device was designed to enable WiFi, IR communication, and laser diode communication, so that various communication methods could be tested. Through the performance test, it was confirmed that power was stably supplied to the captive flight test POD, and the wireless communication performance was verified by measuring the delay time and error rate. As a result, by using our system the POD check-up for the captive flight test was performed wirelessly and the data of the captive equipment could be obtained effectively.

Conditions for Reintroduction of Captive-Bred Endangered Birds: A Review

  • Kim, Sooil;Park, Heonwoo;Cheong, Seokwan
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.3 no.3
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    • pp.129-138
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    • 2022
  • Reintroduction programs have been promoted across the world to recover and rehabilitate endangered birds through ex situ captive breeding and releasing to the nature. The ultimate aims of these reintroduction programs are recovery of sustainable populations in natural habitats. To ensure the success of the reintroduction programs, it is necessary to examine the followings in order to increase the success rate of releasing along with the development of captive breeding techniques: 1) Adequate habitat provision, 2) adaptability of captive-bred individuals, 3) survivability of released individuals, and 4) social interest and will. Before releasing captive-bred individuals, it should be reviewed whether there are habitats in which the limiting factor is removed, and assessed their long-term safety. The quantity and quality of the released individuals must be considered to increase the chances for mate selection, maintain genetic diversity, and acquire the ability to adapt to the wild. The release method must be decided in consideration of characteristics of the target habitats and individuals, and rational means such as careful observation, evaluation, and feedback must be provided throughout the release process. For the long-term success of recovery projects, social awareness, sustainable support, and related experts are needed. Satisfying these criteria can help to increase the success rates of reintroduction programs. For the bird reintroduction program in the future, the feasibility of the methods and procedures must be closely reviewed before starting.

An Economic Study Analysis of Captive Power Plant as a Commercial Plant in the Cost Based Pool (자가발전기의 CBP시장 참여시 수익성 변화 평가)

  • Goh, Do-Hyun;Park, Jong-Bae;Lee, Ki-Song;Shin, Joong-Rin
    • Proceedings of the KIEE Conference
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    • 2005.11b
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    • pp.183-185
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    • 2005
  • This paper discusses an economic study analysis of captive power plant as a commercial plant in the cost based pool market. In this paper I assumed the conversion of a captive power plant owned by factories to a commercial plant and investigated the changes in profitability associated with this. I set the total electricity expense of a captive purpose plant as state A and the costs associated with converting to a commercial purpose plant as state B. Each state subdivided by case which is classified its plant variable cost, type of generation (combined cycle, single cycle) and type of power contract received. After set model for each case, different economic benefits by each case can be calculated.

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Development and Characterization, and Application of Ten Polymorphic Microsatellite Markers in the Crested Ibis Nipponia nippon from South Korea

  • Choi, Eun Hwa;Kim, Gyeongmin;Baek, Su Youn;Kim, Sung Jin;Hwang, Jihye;Jun, Jumin;Jang, Kuem Hee;Ryu, Shi Hyun;Hwang, Ui Wook
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.2
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    • pp.154-158
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    • 2020
  • The Asian crested ibis Nipponia nippon is one of the world's most endangered species. Except for the Sanxii population from China, it is known that all of the crested ibis populations from East Asia have been extinguished. In these days, most of them are being inbred as captive populations in China, South Korea, and Japan, which caused their low expected genetic diversity. Microsatellite markers are well known as a suitable DNA marker for exploring genetic diversity among captive populations of a variety of endangered species. In the present study, ten microsatellite markers were developed for the captive populations of the South Korean crested ibis, which were employed to examine the level of genetic diversity with the two founders from Sanxii, China and the 70 descendants of them. As a result, the mean number of gene diversity, observed heterozygosity, and expected heterozygosity of the captive population were 0.70, 0.84, and 0.70 respectively. It revealed that the captive population of South Korea is as genetically more stable than we expected. In addition, the principal coordinates analysis and genetic structure analyses showed that the captive population of N. nippon can be divided into the two different genetic groups. The developed microsatellite markers here could be helpful for crested ibis conservation in East Asian countries such as China and Japan as well as South Korea.

Relationship between roar sound characteristics and body size of Steller sea lion

  • Park, Tae-Geon;Iida, Kohji;Mukai, Tohru
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.458-465
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    • 2010
  • Hundreds of Steller sea lions, Eumetopias jubatus, migrate from Sakhalin and the northern Kuril Islands to Hokkaido every winter. During this migration, they may use their roaring sounds to navigate and to maintain their groups. We recorded the roars of wild Steller sea lions that had landed on reefs on the west coast of Hokkaido, and those of captive sea lions, while making video recordings. A total of 300 roars of wild sea lions and 870 roars of captive sea lions were sampled. The fundamental frequency ($F_0$), formant frequency ($F_1$), pulse repetition rate (PRR), and duration of syllables (T) were analyzed using a sonagraph. $F_0$, $F_1$, and PRR of the roars emitted by captive sea lions increased in the order male, female, and juvenile. By contrast, the $F_1$ of wild males was lower than that of females, while the $F_0$ and PRR of wild males and females did not differ statistically. Moreover, the $F_0$ and $F_1$ frequencies for captive sea lions were higher than those of wild sea lions, while PRR in captive sea lions was lower than in wild sea lions. Since there was a linear relationship between body length and the $F_0$ and $F_1$ frequencies in captive sea lions, the body length distribution of wild sea lions could be estimated from the $F_0$ and $F_1$ frequency distribution using a regression equation. These results roughly agree with the body length distribution derived from photographic geometry. As the volume of the oral cavity and the length of the vocal cords are generally proportional to body length, sampled roars can provide useful information about a population, such as the body length distribution and sex ratio.

Prediction of Maneuverability of KCS Using Captive Model Test (구속모형시험을 이용한 KCS 선형의 조종성능 추정)

  • Shin, Hyun-Kyoung;Choi, Si-Hoon
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.5
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    • pp.465-472
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    • 2011
  • Recently, ultra large scale of ship is being ordered continuously and because of that, the accurate prediction of ship maneuverability in design stage becomes important matter. The model test like PMM test or CFD analysis are representative methods for predicting the maneuverability of ship. In this study, the captive model tests were carried out for predicting maneuverability of MOERI container ship(KCS) which is opened to the public using X-Y Carriage of Ocean Engineering Wide Tank of University of Ulsan. Considering the dimensions of tank, 2m class model ship was used for captive model test. CMT(Circular Motion Test) was performed for obtaining purer hydrodynamic coefficients related to yawing velocity. For getting hydrodynamic coefficients which cannot be obtained using CMT, PMM test(Planar Motion Mechanism test) were also performed. The maneuverability prediction results by simulation are compared with those of other research institutes.

Prediction of Ship Manoeuvring Performance Based on Virtual Captive Model Tests (가상 구속모형시험을 이용한 선박 조종성능 평가)

  • Sung, Young Jae;Park, Sang-Hun
    • Journal of the Society of Naval Architects of Korea
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    • v.52 no.5
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    • pp.407-417
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    • 2015
  • For the more accurate prediction on manoeuvring performance of a ship at initial design phase, bare hull manoeuvring coefficients were estimated by RANS(Reynolds Averaged Navier-Stokes) based virtual captive model tests. Hydrodynamic forces and moment acting on the hull during static drift and harmonic oscillatory motions were computed with a commercial RANS code STAR-CCM+. Automatic and consistent mesh generation could be implemented by using macro functions of the code and user dependency could be greatly reduced. Computed forces and moments on KCS and KVLCC 1&2 were compared with the corresponding measurements from PMM(Planar Motion Mechanism) tests. Quite good agreement can be observed between the CFD and EFD results. Manoeuvring coefficients and IMO standard manoeuvres estimated from the computed data also showed reasonable agreement with those from the experimental data. Based on these results, we could confirm that the developed virtual captive manoeuvring model test process could be applied to evaluate manoeuvrability of a ship at the initial hull design phase.