• Title/Summary/Keyword: Turning-on time

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Caculating Ship Rudder Angle and Real-Time Mass Estimator Under Dynamic State (동적 상태의 선박 조향각 및 실시간 질량 추정 시스템)

  • Jin–hyuk Myung
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.06a
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    • pp.31-32
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    • 2022
  • In Early vessels did not provide an exact equation for preventig the capsizing vessels. On land, many vehicle rollover prevention technologies using the steady-state Conrning Equations were developed, which showed better performance than the exiting method at sea. For better performance, It is proposed to improve safety mangement when turning vessel using the Ackerman geometic model-based Cornering Equations in this paper.

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A Study of the Effect of Operating Time of a Rocket Motor on the Convective Heat Transfer Coefficient of Nozzle (로켓 모터의 작동시간이 노즐 열전달 계수에 미치는 영향에 관한 연구)

  • Kim, Jinsoo;Kim, Kyungsik;Cho, Seunghwan;Kwon, Youngdoo;Kwon, Soonbum
    • Journal of the Korean Society of Propulsion Engineers
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    • v.17 no.2
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    • pp.24-30
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    • 2013
  • To guarantee the exact control of missile warhead, it is inevitable to ensure the stabilities in the view points of structural and fluid/thermo dynamics of the rocket motor. Specially, despite of shortness in operating time of the rocket motor which is initial turning type of missile, it occurs frequently some problems of ablation at the neighborhood of the nozzle throat, with the result that the system itself gets to failure. In these connections, in the present study, the effect of the operating time of a rocket motor on the coefficient of convective heat transfer at the nozzle wall is investigated by numerical analysis. As a result, it is turned out that the heat transfer coefficient is largest at the just ahead of nozzle throat and decreases with the increase of operating time of the rocket motor. Furthermore, we found that the radius of curvature of throat becomes smaller, the maximum coefficient of convective heat transfer becomes larger.

A study on the influence of service recovery activities on churning commodities (Focus on the Cable-TV Industry) (서비스 회복활동이 상품전환에 미치는 영향에 관한 연구 (케이블TV산업 중심으로))

  • Kyung, Seung Hyun;Cheong, Ki Ju
    • Journal of Service Research and Studies
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    • v.6 no.3
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    • pp.57-78
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    • 2016
  • The purpose of this research is to study how service recovery activities influence customers' commodity churning in the media telecommunication industry(CATV industry). Put it differently, we tried to identify this change of commodity churning rates by the stages of service failures, by which we intend to emphasize the importance of service recoveries. Korean media telecommunication market has already been saturated; customers tend to move to bigger major companies with better customer care increasingly. As once customers gone never returns, CRM functions are being reinforced over the time. We were able to have the following results. First, turning rates, for those experienced service failure, who were dissatisfied with service recovery activities are 2~5 times (monthly average turning rates are 1.3%) higher than those satisfied. Secondly, active service recovery activities at the customer's service request after experiencing service failure lowered churning rates significantly. The most effective timing is service recovery activities pre-recovery stage. Thirdly, reward activities after service recovery activities at the immediate recovery stage is more effective than service recovery at the arranged recovery schedule and reward activities after customer's expressing churning intension. The implications of this study are that firms should engage in service recovery activities at the time of identifying service failures, prior to customer's expressing churning intention, which means relatively lower ROI for the service recovery activities than the times of customers' expressing churning intention.

The Expressional Characteristic of Modern Tattoo Look fashion (복식에 나타난 타투 룩(Tattoo Look) 패션의 표현 특성)

  • 윤정혜;유영선
    • Journal of the Korean Society of Costume
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    • v.51 no.3
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    • pp.87-98
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    • 2001
  • The purpose of this study is to examine the tattoo look in modern fashion from the aspects of 'expression techniques' and 'aesthetic properties'. Tattoos are one of the body decoration which have been continued for a long time all over the world and have contained various meanings in : invocation. symbolization. solidification, exotic tastes, and body decoration. While tattoos have been progressed for the past time, they have been enlarged into body painting, make-up, and even into body art. Besides, their technical skills and equipments have been also developed. Therefore, tattoos are neither tabooed nor restricted in lower class, such as gangsters, bickers, prostitutes, etc., any longer. They are showed in everywhere of our society, running on the fashion. Specially, in fashion, they are shown through the 'tattoo look' designed by talented fashion designers. Futhermore, tattoos are one of the things which have gotten a new value under the Post-modernism and the turning of the century. The various tattoo looks in modern fashion are classified into four categories, according to the expression techniques, the use of see-through, reappearance of primitive body-decoration, application of tattoo patterns, application of street styles'tattoo patterns, make-up & body painting. And, they are also classified into four categories, according to the aesthetic properties Exoticism, Eroticism, Primitivism, and Grotesque.

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studdyon the Field Efficiency of the Plowing Operation of the Power Tillers in accordance withthe Various Field Dimensions. (보장구획의 장단변화에 따른 경운기의 기종별 이경작업 효력에 관한 연구)

  • 최규홍;김종관
    • Journal of Biosystems Engineering
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    • v.2 no.1
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    • pp.49-54
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    • 1977
  • In order to obtain the field efficiency of the power tiller plowing on the various size of and its length-width field tests were performed with 8ps.10ps. power tiller popularly used in the korean rural area, and Satoh 5ps. made in Japan, Land Master 5ps. made in England were tested to compare with the field efficiency of the above power tillers. The results obtained in this tests were as follows ; 1. In considering of the resting time and the refueling time and others, the field efficiency of Satoh was the highest among the power tillers as to be 80%, at the 8ps. power tiller 76.5%, at the 10ps. power tiller 79.3% and the lowest field efficiency was obtained at the Land Master as 75.7%. 2. The field efficiency of the each power tiller increased as the ratio of the length to width of the field was increased. 3. The increasing rate of field efficiency was much bigger in the below the ratio of 5 : 1 but at the upper ratio increased above, the ratio was nearly constant. 4. The field efficiency of the power tiller was higher at the smaller power tiller than the larger, except the Land Master , because of easily operating and turning of the power tiller by virtue of its lighter weight.

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An Experimental Study on the Temperature Control For a Gas Engine Cogeneration System (가스엔진 열병합시스템의 온도제어에 관한 실험적 연구)

  • 장상준;유재석;방효선;한정옥
    • Journal of Energy Engineering
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    • v.5 no.1
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    • pp.28-33
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    • 1996
  • This study was carried out find out the appropriate tuning method of PID controller for a package type gas engine cogeneration system in terms of stabilizing the engine coolant temperature and system heat balance. In order to acquire the proper parameters of the controller, a system transfer function was set as a first order plus dead time model and thereafter model parameters were determined by using several tuning methods. And, with determined values of parameters and the system transfer functions, optimal turning method was selected by simulating the process using MATLAB. From the experimental results, it was found that obtained PID gains made the system stable in various operating conditions.

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A Study on Hand Shape Recognition using Edge Orientation Histogram and PCA (에지 방향성 히스토그램과 주성분 분석을 이용한 손 형상 인식에 관한 연구)

  • Kim, Jong-Min;Kang, Myung-A
    • Journal of Digital Contents Society
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    • v.10 no.2
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    • pp.319-326
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    • 2009
  • In this paper, we present an algorithm which recognize hand shape in real time using only image without adhering separate sensor. Hand recognizes using edge orientation histogram, which comes under a constant quantity of 2D appearances because hand shape is intricate. This method suit hand pose recognition in real time because it extracts hand space accurately, has little computation quantity, and is less sensitive to lighting change using color information in complicated background. Method which reduces recognition error using principal component analysis(PCA) method to can recognize through hand shape presentation direction change is explained. A case that hand shape changes by turning 3D also by using this method is possible to recognize. Human interface system manufacture technique, which controls a home electric appliance or game using, suggested method at experience could be applied.

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Motion planning of a steam generator mobile tube-inspection robot

  • Xu, Biying;Li, Ge;Zhang, Kuan;Cai, Hegao;Zhao, Jie;Fan, Jizhuang
    • Nuclear Engineering and Technology
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    • v.54 no.4
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    • pp.1374-1381
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    • 2022
  • Under the influence of nuclear radiation, the reliability of steam generators (SGs) is an important factor in the efficiency and safety of nuclear power plant (NPP) reactors. Motion planning that remotely manipulates an SG mobile tube-inspection robot to inspect SG heat transfer tubes is the mainstream trend of NPP robot development. To achieve motion planning, conditional traversal is usually used for base position optimization, and then the A* algorithm is used for path planning. However, the proposed approach requires considerable processing time and has a single expansion during path planning and plan paths with many turns, which decreases the working speed of the robot. Therefore, to reduce the calculation time and improve the efficiency of motion planning, modifications such as the matrix method, improved parent node, turning cost, and improved expanded node were proposed in this study. We also present a comprehensive evaluation index to evaluate the performance of the improved algorithm. We validated the efficiency of the proposed method by planning on a tube sheet with square-type tube arrays and experimenting with Model SG.

Response of Rockfish to the Colored Lights (색광에 대한 조피볼낙의 반응)

  • YANG Yong-Rhim
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.2
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    • pp.119-123
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    • 1985
  • The author carried out an experiment to find out the response of rockfish, Sebastes schlegeli(Hilgendorf) to the color lights. The experimental tank($360L{\times}50W{\times}55H\;cm$) was set up in a dark room. Six longitudinal sections with 60 cm intervals are marked in the tank to observe the location of the fish. Water depth in the tank was kept 50 cm level. Light bulbs of 20 W at the both ends of the tank projected the light horizontally into the tank. Two different colored filters were selected from four colors of red, blue, yellow, and white, and they were placed in front of the light bulbs to make different colors of light. Light intensity were controlled by use of auxiliary filters intercepted between the bulb and the filter. The fishes were acclimatized in the dark for 50 minutes before they were employed in the experiment. Upon turning on the light, the number of fish in each section was counted 40 times in 30 second intervals, and the mean of the number of fish in each section was given as the gathering rate of the fish. The colors favourited by the fish was found in the order of blue, white, yellow and red in day time, and yellow, blue, white and red at night time. The gathering rate of fish on illumination period was not constant and fluctuated with irregularity. The difference of the gathering rate on two different colors of light was great and the difference was larger in day time than in night time.

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Wordsworth's Re-Formation of Individuality: "Spots of Time," the Fragment and the Autobiography

  • Park, Mikyung
    • Journal of English Language & Literature
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    • v.56 no.6
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    • pp.1361-1378
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    • 2010
  • This paper argues that it is possible to construct an analogy of the literary fragment to an organic individual on the basis of an autonomous system of organic unity by reading William Wordsworth's ways of self-writing in The Prelude. The organicity of a fragment is borrowed from Friedrich Schlegel's theoretic and literary approach to the Romantic fragment. Focusing primarily on the two "spots of time" in Book Twelfth, I attempt to formulate a reciprocal relationship between a work of art and a literary autobiographer in terms of the self-generativity of the fragment. To be precise, both the fragment and the autobiographical project presuppose and at the same time depend on the engendering force of an organic unity and its resistance to discontinuity, which ironically affirms the persistent threat of disruption and death. Rewriting traumatic childhood experiences as rites of passage into adulthood, the two specified "spots of time" show the dominant mode of memory operative in the poem. Asserting the prominence of the individual as the very vehicle of realizing universal humanity, Wordsworth tries to re-form his individuality grounded in his childhood memories in a literary fashion. Under the premise that the poet is remembered by his posterity, The Prelude is constituted and reconstituted in conjunction with different versions of each memory. The poem also marks the poet's unachieved project of writing a philosophical poem, namely, The Recluse; for this very reason, The Prelude, which is complete in itself, points to an eternal work in progress, turning the truth of every fragment complete in its incompletion. As a trope of fragmentation, an autobiographical individuality is reformed in the poet's process of writing and re-visioning while simultaneously being dispersed once again between words, sentences, and pages.