• Title/Summary/Keyword: turn-taking

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The Design of a Hybrid Engine System Based on a Reciprocal Engine For Unmanned Aerial Vehicles (내연기관 기반 드론용 하이브리드 엔진 시스템 설계)

  • Gang, Byeong Gyu;Kim, Keun-Bae
    • Journal of Aerospace System Engineering
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    • v.14 no.5
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    • pp.42-48
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    • 2020
  • This research illustrates how the hybrid engine system comprising of a two-cycle reciprocal engine with an integrated generator and a battery is prepared for the design process. The purpose of this research is to increase flight endurance taking advantage of the high energy density of hybrid propulsion systems as well as to cope with current environmental issues by reducing fossil fuel. The hybrid system is designed to offer 6 kW power, and the power can be adjusted by controlling the engine's RPM in accordance with load variations. In addition, the battery is adopted to offer extra electric power that this hybrid system cannot cover, and can function as the main power source in limited time in the case of an emergency situation. Besides that, the generator is directly mounted on an engine crank-shaft, and in turn, they can share the same RPM. Thus, it is hypothesized that this integration method can make a compact design possible by reducing space for the installation in the fuselage of UAVs.

A study on the relationship between the symptom of Shanghanlun(傷寒論) and the Nutritive-Gi(營氣) (『상한론(傷寒論)』 병증(病症)과 영기(營氣)의 관계에 대한 연구(硏究))

  • Bang, Jung-kyun
    • Journal of Korean Medical classics
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    • v.30 no.1
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    • pp.211-221
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    • 2017
  • Objectives : The practices of Wei-qi and Nutritive-qi are generally divided into external Mai and internal Mai. However, they are closely interrelated and practiced together. While taking these aspects into consideration, this paper attempts to make interpretations in relation with Nutritive-qi the disease pathogens that appear in Shanghanlun's disease symptoms. Methods : Using the practice and function of Nutritive-qi described in Huangdineijing, the paper shall make interpretations for the patterns of Mawhangtang, patterns of Gaejitang, and the pathologies of pain, oedema, and nosebleed as described in Shanghanlun. Results & Conclusions : The pain from the patterns of Gaejitang differ from that of the patterns of Mawhangtang. First, the pain from the the patterns of Gaejitang cannot be the main symptom. Even if there is a symptom of pain, it's severity is not serious. Second, the pain from the patterns of Gaejiang takes the form of stiffness, and not general bodily pain. The reason for this stiffness is because of the emptiness of Wei-qi that leads to the congestion of Nutritive-qi which in turn causes the lack of qi and blood flow in muscula area such as abdomins. The symptom of oedema where one's body becomes swollen comes from a number of pathogens. First, the flow of meridian becomes hindered due to external dampness, a character which tends to be adhesive when added with humidty, and this results in the blockage of water qi which then causes the coagulation of nutritive blood. Second, when toxic heat is repressed and blocked within the lesser-yang channel, lesser-yang meridian stops working, which causes nutritive blood to clog at the front and back of ears since lesser-yang channel flows through that portion of body. Third, although oedema is not specifically mentioned in the sentences, but there exists the patterns of Daechungyongtang where water lumps are formed due to the accumulation and blockage of watery dampness. The patterns of Daechungyongtang is cuased when meridian is hindered from externally discharging body fluid due to a problem with meridian that blocks the fumigated internal heat which turns into bodily fluid from being discharged externally.

NIR PREDICTIONS OF INDIRECT RESPONSES

  • Claridge, Rovert-Burling;Ross Clarke
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.3103-3103
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    • 2001
  • NIR has been extensively used to predict directly measurable properties of materials that are important to the appropriate industries. Commonly, NIR is used to perform fast, routine tests to improve control response as against the response time for the (normally chemical) base test. This paper discusses the use of NIR to measure indirect properties of materials. In these cases, the pure chemical or physical tests are either unable measure the appropriate parameters (eg GMO modification) or there are mitigating effects that are not properly addressed by the base tests. In particular, we looked at the digestible portion of amino acids within meat and bone meal. This is the desired response measurement by end-users of the product (intensive livestock producers) but is currently unable to be offered as a measurement by producers. The base test method is by controlled feeding trials. These are somewhat cumbersome, taking 2-3 months, involving several sets of animals, and considerable expense. A shortened test (feed trial based) would be of little use, as the precision blows out over short period feeding trials. For example, a rat ileal digestibility test requires around 2 months, and costs some $USD1000. This is clearly impractical test for a producer involved in continuous production, with a 1-2 day turn around. While the amino acid abundance is accessible chemically, the uptake of amino acids into usable material by mammalian species is not simply related to the measured abundance within the material. There are many co-related material properties that might help or hinder uptake, some chemical based (eg protein damage), some indirect (eg palatability), some physiological (intestinal tract response vs speed of throughput). We discuss the approaches taken to provide a suitable reference data set, and present the derived prediction and validation relationships.

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Pre-cluster HEAD Selection Scheme based on Node Distance in Chain-Based Protocol (체인기반 프로토콜에서 노드의 거리에 따른 예비 헤드노드 선출 방법)

  • Kim, Hyun-Duk;Choi, Won-Ik
    • Journal of Korea Multimedia Society
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    • v.12 no.9
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    • pp.1273-1287
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    • 2009
  • PEGASIS, a chain-based protocol, forms chains from sensor nodes so that each node transmits and receives from a neighbor. In this way, only one node (known as a HEAD) is selected from that chain to transmit to the sink. Although PEGASIS is able to balance the workload among all of the nodes by selecting the HEAD node in turn, a considerable amount of energy may be wasted when nodes which are far away from sink node act as the HEAD. In this study, DERP (Distance-based Energy-efficient Routing Protocol) is proposed to address this problem. DERP is a chain-based protocol that improves the greedy-algorithm in PEGASIS by taking into account the distance from the HEAD to the sink node. The main idea of DERP is to adopt a pre-HEAD (P-HD) to distribute the energy load evenly among sensor nodes. In addition, to scale DERP to a large network, it can be extended to a multi-hop clustering protocol by selecting a "relay node" according to the distance between the P-HD and SINK. Analysis and simulation studies of DERP show that it consumes up to 80% less energy, and has less of a transmission delay compared to PEGASIS.

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A Case of Becker's Type Congenital Myotonia (Becker형 선천성 근긴장증 1례)

  • Yun, Sung-Hwan;Hah, Jung-Sang;Lee, Jun
    • Journal of Yeungnam Medical Science
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    • v.16 no.1
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    • pp.125-130
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    • 1999
  • Congenital myotonia is a hereditary disorder of the skeletal muscle. The most characteristic features of the disease are myotonia and variable muscular hypertrophy. Molecular biologic investigations have revealed that mutations in the gene of the human skeletal muscle chloride ion channel protein are a cause of the disease. The Becker's type congenial myotonia is clinically similar to the autosomal dominantly inherited congenital myotonia (Thomsen's disease). Both disorders are characterized electrophysiologically by increased excitability of muscle fibers. reflected in clinical myotonia. In general, Becker's type congenital myotonia is more severe than Thomsen's disease in muscular hypertrophy and weakness. The authors recently experienced a 25-year-old female patient who has no family-related disease history and who has conspicuous muscular hypertrophy and the stiffness with muscles which occurred from the age of 3 or 4. Clinically she showed the authors a percussion myotonia. On electrophysiological study, exercise and repetitive stimulation of the abductor digiti quinti muscle disclosed a decline in the compound muscle action potential. Biopsy of biceps muscle revealed enlargement of muscle fibers with marked nuclear internalization. After the oral taking the Mexiletine, the patient showed a favorable turn a little with her stiffness of muscles. So we authors are reporting one case of Becker's type congenital myotonia with review of literatures.

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Pre-Computation Based Selective Probing (PCSP) Scheme for Distributed Quality of Service (QoS) Routing with Imprecise State Information

  • Lee Won-Ick;Lee Byeong-Gi
    • Journal of Communications and Networks
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    • v.8 no.1
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    • pp.70-84
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    • 2006
  • We propose a new distributed QoS routing scheme called pre-computation based selective probing (PCSP). The PCSP scheme is designed to provide an exact solution to the constrained optimization problem with moderate overhead, considering the practical environment where the state information available for the routing decision is not exact. It does not limit the number of probe messages, instead, employs a qualitative (or conditional) selective probing approach. It considers both the cost and QoS metrics of the least-cost and the best-QoS paths to calculate the end-to-end cost of the found feasible paths and find QoS-satisfying least-cost paths. It defines strict probing condition that excludes not only the non-feasible paths but also the non-optimal paths. It additionally pre-computes the QoS variation taking into account the impreciseness of the state information and applies two modified QoS-satisfying conditions to the selection rules. This strict probing condition and carefully designed probing approaches enable to strictly limit the set of neighbor nodes involved in the probing process, thereby reducing the message overhead without sacrificing the optimal properties. However, the PCSP scheme may suffer from high message overhead due to its conservative search process in the worst case. In order to bound such message overhead, we extend the PCSP algorithm by applying additional quantitative heuristics. Computer simulations reveal that the PCSP scheme reduces message overhead and possesses ideal success ratio with guaranteed optimal search. In addition, the quantitative extensions of the PCSP scheme turn out to bound the worst-case message overhead with slight performance degradation.

Analysis on Employment Effects of Working Hours Reduction with the Emphasis of Industry Size (근로시간 단축의 고용효과 분석: 기업규모별 추정을 중심으로)

  • Yoo, Gyeongjoon;Lee, Jin
    • Journal of Labour Economics
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    • v.37 no.1
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    • pp.1-28
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    • 2014
  • We use a set of Korea panel data to estimate effects of legal working hours reduction on actual hours worked and employment effects, through panel econometrics methods. Taking account of sequential decrease in legal hours worked since 2004, we estimate the relationship between legal and actual working hours by size of industries. It is found that one hour reduction of legal hours per week caused 0.44 to 1.05 actual hours worked on average per week, depending on different industrial sizes. Also, estimated employment effects were not unanimously determined, rather they turn out to be clearly size-dependent, which provide different results from exiting literature. Our analysis proposed in this work can be restrictive as, for instance, there is significant lack of data for foreign workers, particularly in the small-sized industries. Subsequent empirical analysis is expected.

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The Kinetic Analysis K-study of Roche Technique in Horse Vaulting (도마 Roche 기술의 운동역학적 사례분석)

  • Yeo, Hong-Chul;Ryu, Jae-Kyun
    • Korean Journal of Applied Biomechanics
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    • v.18 no.4
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    • pp.201-207
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    • 2008
  • The purpose of this study was to examine the Roche technique performed by three male subjects in 2003 Taegu World Students Game. Conclusions are as followed. If the angular momentum was increased to counter-clockwise on voulting, the momentum acted like an interrupting factor of body spinning force. The biggest body angle was at VTD phase and the smallest was at BTO phase. At the phase of contacting on vaulting board and taking off from the vaulting board, the biggest personal angle difference between VTD and BTO was found. As the Roche technique was needed not only to fly high but also to increase body spinning rate, the projection angles of Roche technique were showed smaller than those of Cuervo technique. The angular velocity was peak during 2 times forward turn phase. The angular momentum was influenced by angular velocity from BTO and VTD phase.

Effects of Metal and Metalloid Contamination on Microbial Diversity and Activity in Agricultural Soils

  • Tipayno, Sherlyn C.;Chauhan, Puneet S.;Woo, Sung-Man;Hong, Bo-Hee;Park, Kee-Woong;Chung, Jong-Bae;Sa, Tong-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.1
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    • pp.146-159
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    • 2011
  • The continuous increase in the production of metals and their subsequent release into the environment has lead to increased concentration of these elements in agricultural soils. Because microbes are involved in almost every chemical transformations taking place in the soil, considerable attention has been given to assessing their responses to metal contaminants. Short-term and long-term exposures to toxic metals have been shown to reduce microbial diversity, biomass and activities in the soil. Several studies show that microbial parameters like basal respiration, metabolic quotient, and enzymatic activities, including those of oxidoreductases and those involved in the cycle of C, N, P and other elements, exhibit sensitivity to soil metal concentrations. These have been therefore, regarded as good indices for assessing the impact of metal contaminants to the soil. Metal contamination has also been extensively shown to decrease species diversity and cause shifts in microbial community structure. Biochemical and molecular techniques that are currently being employed to detect these changes are continuously challenged by several limiting factors, although showing some degree of sensitivity and efficiency. Variations and inconsistencies in the responses of bioindicators to metal stress in the soil can also be explained by differences in bioavailability of the metal to the microorganisms. This, in turn, is influenced by soil characteristics such as CEC, pH, soil particles and other factors. Therefore, aside from selecting the appropriate techniques to better understand microbial responses to metals, it is also important to understand the prevalent environmental conditions that interplay to bring about observed changes in any given soil parameter.

The Types of Color Coordination and Their Characteristics In Contemporary Women′s Fashion (현대 여성 패션에 나타난 색채 코디네이션의 유형과 유형별 특성 분석)

  • Kwon Hae-Sook;Shim Eun-A
    • Journal of the Korea Fashion and Costume Design Association
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    • v.6 no.3
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    • pp.139-152
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    • 2004
  • The main objective of this research is to investigate the color coordination types and their characteristics of contemporary female fashion by reviewing 'pre-a-porter Collections' of four collections (i.e., cities) - Paris, Milan, New York, London - from the periods of 2000 S/S to 2002/3 A/W. Through the review of various books and articles written on the subject, the color coordination types and their characteristics were categorized and defined. The data was collected by reviewing 'pre-a-porter Collections' magazine and total 4,269 observations were made. These in turn were categorized into eight color coordination and three color tone categories through the content analysis. Frequency analysis was used to analyse the data. The findings are as follows; First of all, there were 8 observable color coordination categories in contemporary women's fashion. The most used color coordination was chromatic & achromatic color coordination. It was followed by chromatic identical, and then by achromatic identical color coordination. These three color coordinations were the majority, comprizing 73.4% of the total. The rest were in the order of complementary, gradation, similarity, accent. And the most used tone type was contrasting tone and followed by similar and identical. Next, the analysis of each coordination categories shows that; The chromatic identical coordination focused on presenting its own unity or break it using the contrasting color tone. Meanwhile, the achromatic identical coordination project a clean and strong feeling through black and white combination or a subtle feeling through the different material combination. The chromatic & achromatic coordination showed strong colors and contrasting tones of clear and bright colors. Meanwhile, the characteristics of complementary coordinations are that these coordinations seem to free the colors and show the subtle changes in tones very clearly. The gradation coordination was used to create a cool and lively feeling. Next, the similarity coordination seems to create feminine and warm feeling by taking advantage of similar color feelings, often through the use of warm to warm, cool to cool color matching. Lastly, the accent coordination, through the use of contrasting tones emphasizes the differences in colors, while separation coordination mostly uses black and white on various color coordinations.

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