• Title/Summary/Keyword: stability of turning

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Response of Marbled Sole to the White Lights (백색광에 대한 문치가자미의 반응)

  • YANG Yong-Rhim
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.6
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    • pp.558-562
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    • 1986
  • The purpose of this study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by using marbled sole, Limanda yokohamae (Gunther). An experimental tank ($360L{\times}50W{\times}55H\;cm$) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 40 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 1.9 lux ($1.2{\sim}2.9\;lux$) in the daytime and 0.7 lux ($0.5{\sim}1.1\;lux$) at night. The variation of the gathering rate of fish in illumination time was small and comparatively fluctuated with stability.

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Dynamic Analysis of A High Mobility Tracked Vehicle Using Compliant Track Link Model (유연성 궤도 모델을 사용한 고기동성 궤도차량의 동역학 해석)

  • 백운경;최진환;배대성
    • Journal of KSNVE
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    • v.9 no.6
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    • pp.1259-1266
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    • 1999
  • The objective of this investigation is to develop a compliant track link model and apply this model to the multi-body dynamic analysis of high mobility tracked vehicles. Two major difficulties encountered in developing the compliant track models. The first one is that the integration step size must be kept small in order to maintain the numerical stability of the solution. This solution deals with high oscillatory signals resulting from the impulsive contact forces and stiff compliant elements to represent the joints between the track links. The second difficulty is due to the large number of the system equations of motion of the three dimensional multibody tracked vehicle model. This problem was sloved by decoupling the equations of motion of the chassis subsystem and the track subsystems. Recursive methods are used to obtain a minimum set of equations for the chassis subsystem. Several simulation scenarios were tested for the high mobility tracked vehicle including accelaeration, high speed cruising, braking, and turning motion in order to demonstrate the effectiveness and validity of the methods proposed in this investigation.

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Study on Improving Energy-Efficiency of Set-top Box (셋톱박스의 에너지 효율 개선에 관한 연구)

  • Lee, Sang-Hak;Yun, Jung-Mee
    • The KIPS Transactions:PartD
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    • v.18D no.3
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    • pp.197-204
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    • 2011
  • Set-top Box which receives broadcasting signal and delivers it to display device such as TV usually doesn't have low-power mode, standby power mode. On the other side, most consumer electronics support standby power mode. The main reasons come from technical barriers and operational stability. Set-top box normally consumes 80~90% power of active mode even though turning off. This is much higher compared to other consumer electronics which consume less than 1W in standby power mode. However, most developed countries including Korea are enforcing the regulations which enhance energy efficiency of set-top box. This paper describes design and development of low-power set-top box. Key technologies are SoC supporting low-power mode, system hardware and software operating in separated power mode, and middleware managing the power with broadcasting system. Finally, we show energy saving expectation through development and proliferation.

A Systematic Approach to Decide Maximum Berthing Ship Size Coupled with Berth Design Criteria - A Case of Port of Ulsan - (부두 설계기준을 고려한 접안가능 최대선형의 결정에 관한 연구 - 울산항을 중심으로 -)

  • Jun, Sang-Yup;Kim, Young-Mo;Woo, Byung-Goo;Chung, Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.1
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    • pp.45-54
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    • 2008
  • "Summer Deadweight Tonnage(SDWT)" is used as the criteria of the berthing capacity when establishing port entry limits under current guideline. The important factors affecting to the maximum ship size of possible berthing are mass, length and breath of the ship rather than deadweight. Therefore this guideline should be modified to ensure safety and efficient operation of berth. This study aimed to propose a rational guideline to adjust the berthing capacity. In order to decide proper berthing capacity, three berths of Port of Ulsan were selected and systematic evaluations for the safety of passage transit, berthing maneuvers, ship motions at berth and stabilities of structures were conducted. Small changes of ship size had little effect on those characteristics and little significant differences were found according to the increase of ship size at the same displacement. The evaluation results of the increasement of 50% of berthing capacity at 20,000 DWT, 25% at 40,000 DWT and 13% at 150,000 DWT were within the design criteria in which the berths were built. Therefore, if the channel width, diameter of turning circle, berth length and mooring arrangements are satisfied with the criteria, the current berth limitations should be adjusted by the displacement. as substitute for the deadweight.

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Effect of Transient Condition on Propeller Shaft Movement during Starboard Turning under Ballast Draught Condition for the 50,000 DWT Oil Tanker (50,000 DWT 유조선의 밸러스트 흘수에서 우현 전타시 과도상태가 프로펠러축 거동에 미치는 영향 연구)

  • Lee, Jae-ung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.4
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    • pp.412-418
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    • 2020
  • Generally, the propeller shaft that constitutes the ship shaft system has different patterns of behavior due to the ef ects of engine power, propeller load and eccentric thrust, which increases the risk of bearing failure by causing local load variations. To prevent this, different studies of the propulsion shaft system have been conducted focused the relative inclination angle and oil film retention between the shaft and the support bearing, mainly with respect to the Rules for the Classification of Steel Ships. However, in order to secure the stability of the propulsion shaft via a more detailed evaluation, it is necessary to consider dynamic conditions, including the transient state due to sudden change in the stern wakefield. In this context, a 50,000 DWT vessel was analyzed using the strain gauge method, and the effects of propeller shaft movement were analyzed on the starboard rudder turn which is a typical transient state during normal continuous rate(NCR) operation in ballast draught condition. Analysis results confirm that the changed propeller eccentric thrust acts as a force that temporarily pushes down the shaft to increase the local load of the stern tube bearing and negatively affects the stability of the shaft system.

The Achievements and Limitations of Petit Bourgeois Desires in "Oksosun Story" (<옥소선 이야기> 속 소시민적 욕망의 성취와 한계)

  • Lee, Won-young
    • Journal of Korean Classical Literature and Education
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    • no.32
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    • pp.327-355
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    • 2016
  • This study aims to identify petit bourgeois desires through the characters in "Oksosun Stories" from Cheonyerok, an eighteenth-century Yadam anthology. The desires and motivations of the characters are quite secular and egocentric. Because of this, their shared characteristics are similar to those of the petit bourgeois, as neutral existence begins to emerge during the transition from feudal to modern society. The concept of petit bourgeois generally means the public and the working class of modern society. The main character's behavior in the story differs little from general petit bourgeois attitudes. An important belief in petit bourgeois is not the ruling ideology in society but the achievement and stability of realistic and ordinary desires to fulfill their lives' satisfaction. Also selfish or antisocial attitudes and boundary characteristics appear in the process, depending on whether subject having any desire. However, the character's actions are limited in the governance system of a huge reality. And It is characterized by end goal being to meet their upward mobility and stability. This corresponds with Seang's (書生) actions of turning his back on his family and country as well as promising Jaran his love; and, he redeems himself with his family and society by acquiring stability after he passed the state examination. Furthermore, the contemporary significance of this work demonstrates Seang (書生) discovering his desires for human love; therefore, in order to affirm and gratify this desire, he endures the societal state of semi-feudalism against filial duty (不孝), disloyalty (不忠), and non-chastity (不烈), and he acts independently. In addition, on the strength of his pursuit of his desires, Oksosun frees herself from the caste restraint called gisaeng (妓生) and affirms her desire to become a subject of love, but she then deviates from the social system. Moreover, the limitations and achievements of the petit bourgeois are indicated in the actions of recognizing the social threshold of their past in the process, making independent efforts using their capabilities, fulfilling success in the state examination with their intellectual capacity, and re-entering society. From the late Chosun Dynasty to modern times, there is not only the type of contemporary people who hunger for fulfillment of their personal desire and live in free will, but there is also the feudal type that is still lacking in the understanding of independent life. This is not as different as in these present times. This literature asserts the meaning of awakening one's self-existence and assigning great value to the fulfillment of self-desires against the odds that are created by socio-political, cultural, economic norms of the era. "Oksosun Story" affirms the small efforts and successes of private individuals in reality. It also validates the search for life happiness through positivity. In this sense, even the contemporary reader would derive valid meaningfulness from this literature.

A Study on dress and its Ornaments for farm-music (농악복식(農樂服飾)에 관한 연구(硏究))

  • Suh, Ok-Kyu
    • Journal of the Korean Society of Costume
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    • v.12
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    • pp.9-23
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    • 1988
  • This study is on the costumes for Korean traditional play, Nong-ak(farm music), and intends to analyze their aesthetic features, laying emphasis on Pilbong Nong-ak, Im sil, Chollanam-do. About its origin there are many kinds of theories; for example, the theory of hoping stability, the theory of it being related with Buddhism, the theory of martial music, etc. Shamanic, Buddhist, and martical fators that support these theories are expressed through flags, bells, drums, Deograe (half-coats), Cheonrips (sang-mo, felf hats), go-kkals(peaked hats), colored lines called 'ga-sa', which are used in Nong-ak. The characteristic of the costumes used in Pilbong Nong-ak is that it keeps its conservativeness and the costumes of its members are various and splendid. For example, leader groups' black half coats, Changbu's and Hwa-dong's red and bule over coats are remarkable. Particpants wear gok-kal or cheonrip, trousers and half coats which are the basic costumes of Korean Hanbok, and wear blak half coats or blue vests and put blue, red, and yellow lines around them. The colors and knotting methods of those lines in this region are the same with those of chollawoo-do and Kyongi province, but different form those of Kongwon and Kyong-sang province using green, red, and yellow colors. This comparison of colors shows each region's preference of peculiar colors and those colors coincide with colors used in flags. The research on the aesthetic characteristics of Nong-ak clothes through each region's clothes tells us that these can be linear clothes which have expressiveness as stage clothes used in Madangori, the play which is performed in the field, and modern spatial formativeness. Those characteristics are as follows; 1. The expressions of a rhythmical and daring round line by turning a long line of sang-mo. 2. Various rhythms according to the attaching methods. 3. The expressions of thick, simple, and daring color lines. 4. Natural beauty of materials. 5. The popular simplicity and non-technicality 6. The beauty of five-direction colors, Oriental ideal colors Consequently in this study our national consciousness of beauty are examined through clothes. It is suggested that the aesthetic characteristics of Nong-ak clothes and ornaments should be effectively expressed, for this purpose. interests in participants' clothes should be increased in order to prevent the confusion of each region's features. Also it is necessary to improve color lines, their length, width, and knotting methods, and beautify instrument. Finally this study intends to bring the reappraisal about the art of Nong-ak clothes and its re-establishment in view of modern aesthetic consciousness.

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Study of Plant Growth Inhibition with Edible Sweetener Saccharin and Acesulfame Potassium (식용 감미료 사카린과 에이스셜팜 칼륨의 식물 성장 저해 연구)

  • Donggiun Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.661-667
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    • 2023
  • Five commercially available edible sweeteners are used as diet products because they can replace sucrose. In studies on the effects on animals and the human body, stability has been proven by excreting-oriented studies with characteristics of animal cells, and accumulation in small amounts has been ignored. On the other hand, plants can absorb, degrade, and accumulate foreign substances, so the effect of degradability and accumulation potential can be studied using plants. Metabolic effects in plants of commercially available saccharin and acesulfame potassium (Ace K) were tested using germinated barley and bean sprouts. In germinated barley and bean sprouts, saccharin and ace K showed inhibitory effects on plant growth in all organs from low concentrations in leaves, stems and roots. In addition, it can be observed that the symptoms of death appear clearly over time, so it can be seen that they are accumulated in the body of the plant. As the accumulated amount increases, the toxic effect increases and the plant reaches a state where it is unable to metabolize, turning black from the tip of the leaf and reaching a state of death. In order to remove the accumulated artificial sweetener, recovery was attempted by culturing in distilled water, but it acts as a substance that is not degraded and dies without avoiding toxicity. Saccharin and ace K cannot be excreted from the cell. Its toxic effects are thought to be persistent, inhibiting growth and eventually leading to cell death.

A Kinematical Analysis of Belle Motion on Parallel Bars (평행봉 Belle 기술동작의 운동학적 분석)

  • Kong, Tae-Ung
    • Korean Journal of Applied Biomechanics
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    • v.15 no.4
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    • pp.43-53
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    • 2005
  • This study is to define how the difference of athletic change influence on the last regrasp after somersault in Belle movement of parallel bars. For his study, the following conclusion was produced by analysis of athletic change by means of three dimensional visual image in three athlete of nation. 1. As the picture of S1, there are total used time(2.01 sec), S3(2.17 sec) and S2(2.19 sec). In case of a short needed time, it is difficult for them to perform the remaining movement of the vertical elevating flight easily and comfortably, it is judged as performing the small movement with restrict swing. 2 In the change of body center sped by each event, it is calculated as $-89.1^{\circ}$ the narrowest in S1, $-81.96^{\circ}$ the widest and then $86.34^{\circ}$ in S3. In E3 event, average compound speed is 4.07m/s, S2 showed the fastest speed of 4.14m/s whereas S1 the narrowest angle of 3.95m/s. 3. A shoulder joint and coxa are the period of mention in E3. In E4 which was pointed out the longest vertical distance, S2 that is indicated the highest vertical height as the period of detach in parallel bars. showed -3.91m. This is regarded as a preparatory movement for dynamic performance after using effectively elastic movement of shoulder joint and coxa while easily going up with turning back movement. In the 5th phrase, long airborne time and vertical change position is showed as the start while regrasping securely air flight movement from high position. 4. In E5, a long flight time and a long vertical displacement were shown as the regrasp after somersault efficiently in high position with stability from the point of the highest peak of the center of the body. Especially, S2 is marked as a little bit long position, while S1 is reversely indicated as performing somersault and unstable motion in a low position. 5. In E3, at the point of the largest extension of the shoulder joint and hip joint the shoulder joint is largely marked in $182^{\circ}$ and the hip point $182^{\circ}$ in S2. The shoulder joint is marked at the smallest angle in $177^{\circ}$ and the hip point $176^{\circ}$ in S1. And S1 is being judged by its performance of the less self - confident motion with lessening a breath of swing. S2 makes the most use of flexion and extension of the shoulder joint and the hip joint effectively. It was performed greatly with swinging and dropping the rotary movement and the rotary inertia naturally. 6. In E6, as the point of regrasp of the upper arm in parallel bars it is recognized by the that of components of vertical and horizontal velocity stably. During this study, the insufficient thing and the study on the parallel bars at a real game later are more activated than now. If it is really used as the basic materials by means of Belle Picked Study of Super E level after Bell movement, you may perceive the technique movement previously and perform without difficulty. Especially, such technique as crucifix is quite advantageous for oriental people thanks to small body shape condition. In conclusion we will nicely prepare for our suitable environment to gradually lessen trials and errors by analyzing and studying kinematically this movement.

Effect of hot-air drying temperature on nutritional components and rehydration rate of sweetpotato leaves (열풍건조 온도에 따른 고구마 잎의 영양성분 및 수화복원성 변화)

  • Jeong, Da-Woon;Park, Yang-Kyun;Nam, Sang-Sik;Han, Seon-Kyeong
    • Food Science and Preservation
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    • v.22 no.4
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    • pp.498-504
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    • 2015
  • The purpose of the present study is to provide preliminary data for turning sweetpotato leaves into dehydrated vegetables. To achieve this goal, we have gone through the process of hot-air drying the leaves of sweetpotato that are usually thrown away and examined the drying speed and rehydration resilience, then made a comparative analysis of the general ingredients, lutein, $\beta$-carotene and chromaticity. The drying speed reached the peak at a temperature of $70^{\circ}C$. As for other general ingredients, there was no significant difference according to temperature. The content of lutein, which is a functional ingredient, was large in Shinmi with $171.59{\mu}g/g$ at a temperature of $40^{\circ}C$; small in Hayanmi with $73.75{\mu}g/g$ at a temperature of $70^{\circ}C$. The content of $\beta$-carotene was large in Shinmi with $379.59{\mu}g/g$ at a temperature of $40^{\circ}C$; small in Hayanmi with $170.78{\mu}g/g$ at a temperature of $70^{\circ}C$. The content of functional materials was the largest at a temperature of $40^{\circ}C$, and decreased in the order of temperatures at $50^{\circ}C$, $60^{\circ}C$, and $70^{\circ}C$. As for rehydration stability, rehydration rate in both Shinmi and Hayanmi was the highest at a temperature of $40^{\circ}C$ with 233.93% and 223.47% respectively. To summarize, the quality of dried sweet potato leaf was more affected by temperature than by drying time, and low temperature drying resulted in better product value.