• Title/Summary/Keyword: Transfer stability

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Kinematical Analysis of Angle and Angular Velocity of the Body Segment on Spike in Volleyball (배구 스파이크시 신체분절의 각도와 각속도에 대한 운동학적 분석)

  • Cho, Phil-Hwan
    • Korean Journal of Applied Biomechanics
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    • v.17 no.1
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    • pp.191-199
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    • 2007
  • This study was conducted to examine the biomechanical characteristics of open spike in the volleyball to improve the technique of the volleyball spike. The subjects were six male college and high school athletes. The motions of volleyball spike were filmed by using two Sony VX 2000 Video Cameras. The mechanical factors were angle and angular velocity of body segments in the upper and the lower limbs. The conclusions were as follows; 1. The angle of the shoulder joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 2. The angle of the elbow joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 3. The angle of the wrist joint of the skilled showed smaller than that of the unskilled in impacting of the volley ball spike. 4. The angle of the hip joint of skilled showed larger than that of unskilled in impacting of the volley ball spike. 5. The angle of the knee joint of the skilled and the unskilled showed same in take off and impacting of the volley ball spike, and that of the skilled showed smaller than that of the unskilled in take-off touchdown and touchdown after impact of the volley ball spike. 6. The angle of the ankle joint of skilled showed larger than unskilled in take-off of the volley ball spike. 7. The angular velocity of the shoulder joint, elbow joint, wrist joint of the skilled showed faster than that of the unskilled in impacting of the volley ball spike. Taken together the result of them, I have come to conclusion that knee joint angle in touchdown of the take off should be decreased and knee joint angle in take off should be increased, and then stability of the take off should be made and, and that extension of the elbow joint should be made and wrist joint angle decreased and shoulder and hip joint angle increased, and then C.O.G of the arm and hand should be positioned ahead C.O.G of the body in impacting for effective impact of the spike, and that the transfer of the angular velocity of body segments for effective impact of the spike make from the proximal segment to the distal segment at spike in volleyball.

Estimation of Subsurface Structure and Ground Response by Microtremor (상시미동에 의한 지하구조와 지반응답의 추정)

  • Hwang, Min-Woo;Kim, Sung-Kyun
    • Journal of the Korean earth science society
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    • v.23 no.4
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    • pp.380-392
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    • 2002
  • The purpose of the present study is to evaluate the usage of microtremor in estimation of subsurface structure and ground response to strong ground motion. To accomplish the purpose, the current status of microtremor study are reviewed and microtremors recorded at several stations are analysed. First of all, the stability of microtremor is examined through the analysis of microtremors recorded for 80 seconds per hour during the time from 10 p.m. to 6 a.m. for eight hours at night time. It is found that the shape of microtremor spectra of low frequency below 10Hz is approximately invariable with time and the spectra contain informations about subsurface structure. The subsurface structures estimated from the predominant frequency determined from the recorded microtremors are compared with the known ones from geophysical surveys at several stations in Kyungju. The comparison of structures shows rough agreements at most stations. Horizontal to vertical spectral ratio(HVSR) technique for microtremor has been proposed as an indirect method to determine ground response to strong ground motion. The HVSR for microtremors recorded in Kyungju is calculated and compared with theoretical transfer function calculated from the known structures. The comparison shows rough coincidence of the peak frequency of spectra between them.

Development of the Elementary Science Curriculum to Enhance Creative Problem-Solving Abilities: Theme Based Construction of Contents (창의적 문제해결력 신장을 위한 과학교육과정 개발 연구-주제 중심의 초등과학교육과정 내용구성-)

  • Cho, Youn-Soon;Choi, Kyung-Hee;Suh, Ye-Won
    • Journal of The Korean Association For Science Education
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    • v.18 no.4
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    • pp.527-537
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    • 1998
  • This article is a part of a research on the elementary science curriculum development to enhance creative problem-solving abilities. The components of the curriculum have been identified as 'scientific knowledge', 'process skills' & 'divergent/critical thinking'. Among these components, construction of the scientific knowledge that enables creative problem-solving abilities has been selected as an intensive research topic for the purpose of the present research. To avoid or to prevent the knowledge learned from separate facts and concepts, five themes have been selected so as to incorporate with all three areas of the elementary science curriculum, i.e., physical science, earth science and life science. The five themes are, 'structure', 'change', 'interaction', 'energy' and 'stability'. The contents of elementary science, which have been selected from the 3rd, 6th and 7th National Elementary Science curriculum, were reconstructed based on the five themes given above. The results of reconstruction are presented in the form of matrix, such that the vertical axis represents how the concepts are related within each domain of science, while the horizontal axis shows how the concepts are interconnected between domains of science. Therefore, based upon the five themes, individual or separate knowledge can be put into more unified knowledge so that contribution of knowledge transfer to new ones can be expected for leaners who will be creative in problem-solving. The process and products of the curriculum development as well as the background of the present research are described and discussed in detail.

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Synthesis of Mesoporous Pt-Au Alloy Electrode by Electrodeposition Method for Direct Methanol Fuel Cell (전기화학적 증착법에 의한 직접 메탄올 연료전지(DMFC)용 메조포러스 백금-금 합금전극제조)

  • Park, Eun-Kyung;Ahn, Jae-Hoon;Kim, Young-Soo;Kim, Kyung-Hwa;Baeck, Sung-Hyeon
    • Korean Chemical Engineering Research
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    • v.46 no.4
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    • pp.727-731
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    • 2008
  • Mesoporous Pt-Au alloy films were successfully fabricated on ITO-coated glass by electrodeposition method using tri-blockcopolymer (P123) as a templating agent. The electrolyte consisted of 10 mM hydrogen hexachloroplatinate ($H_2PtCl_6$), 10 mM hydrogen tetrachloroaurate ($HAuCl_4$), and proper amount of P123. For comparison, control samples were electrodeposited without $HAuCl_4$ and P123. Film composition was determined by EDS(Energy Dispersive X-ray Spectroscopy), and the mesoporous structure was confirmed by TEM(Transmission Electron Microscopy). SEM(Scanning Electron Microscopy) was utilized to examine surface morphology, and it was observed that the addition of P123 affected the particle growth, resulting in the significant change of surface morphology. Methanol oxidation and CO oxidation were carried out to investigate electrocatalytic activities of synthesized samples. It was observed that the catalytic activity was strongly dependent on the film compositions. Compared with nonporous electrode prepared without P123 templating, mesoporous films prepared with P123 templating showed much higher catalytic activities and stability for both methanol oxidation and CO oxidation. These enhanced electrocatalytic activities were due to the high surface area and facilitated charge transfer of mesoporous films.

Diagnosis of Organizational Culture: Focused on Public Institutions (조직문화에 대한 진단: 공공기관을 중심으로)

  • Lee, Hyangsoo;Lee, Seong-Hoon
    • Journal of Digital Convergence
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    • v.15 no.3
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    • pp.9-16
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    • 2017
  • Organizational culture provides organizational members with identity, homogeneity and behavioral guidance, and promotes organizational commitment and enhances the stability of social systems. What organizational culture positively influences organizational performance? In this study, we tried to categorize organizational culture as creativity, change, cooperation, trust and knowledge sharing for specific public institutions and to diagnose the organizational culture by examining the level of recognition of the organizational members. The purpose of this study is to investigate the effect of organizational culture on organizational culture. The result of this study shows that the degree of future - oriented and cooperative culture of the public institutions that are the subject of research is not so high. In order to improve the performance of the organization, it is necessary to create a futuristic and cooperative culture. In order to create such a culture, various efforts must be made to continuously communicate and build trust among the members of the organization. In particular, leadership efforts to distribute, transfer, and trust authority to subordinates are a priority. In other words, it is very difficult to build a future-oriented, collaborative culture successfully without the efforts of managers.

The New Technology Development Strategy of Cosmeceuticals with Use Advanced Materials Resources (신소재 자원을 활용한 기능성화장품의 신기술 개발전략)

  • Kim Ju-Duck
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.3 s.47
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    • pp.427-438
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    • 2004
  • Cosmeceuticals products we not the products simply for moisturizing and protecting skin but the ones for encouraging to make improvements on wrinkles and helping to whiten, tan, and protect skin against ultraviolet light. In a broader sense, they refer to products with aiming to maintain healthy condition of skin such that skin troubles could be improved or aging of skin could be delayed. However, cosmeceuticals should not have any side effects because they are applied to the whole body for a long period of time differing from medical products which are used on specific areas for a short time. The number of such cosmeceuticals has increased from 500 in 2001 to 2300 in 2003. In order to develop and broaden the scope of cosmeceuticals, the concept of cosmetics needs to be changed from caring skin to delaying aging of the skin and reviving cells. For this purpose, high-valued materials should be developed through basic researches related to the biological function of skin, in vivo experiment and reaction of skin in response to various stimuli using biotechnologies and bioengineering methods. At the same time, it should be proceeded to develop new nano materials for overcoming skin barriers and transfer matericals for helping to absorb effective substances and maintaining stability.

Analysis of Economic Effects and Basic Theoretical Frameworks of ITQ Fishery Management - Focusing on the Red Crab Trap Fishery - (ITQ 어업관리의 기본이론과 경제적 효과분석 - 붉은대게어업을 중심으로 -)

  • Lee Sang-Go;Lee Yong-Soo
    • The Journal of Fisheries Business Administration
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    • v.36 no.3 s.69
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    • pp.119-139
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    • 2005
  • The purpose of this paper is to provide information that will help both fishing industry and fisheries authority understand the principals of individual transferable quota(ITQ) fishery management. Theoretical frameworks and primary features of ITQ fishery managemenet are the assignment of exclusive property rights for harvest of common - property fisheries resources. An ITQ fishery management is fundamentally different from the conventional fishery management and it gives an individual fisherman the right to catch a specified quantity of fish, his quota. With ITQ, fisherman's quotas are transferable, in whole or in part. An ITQ is a property with certain rights of use, namely, the right to catch a given quantity and species of fish in a specific location during a specific period of time. The right is exclusive in the sense that no one else has the right to use the quota without the owner's permission. The property may be assigned, traded, and exchanged; i.e., the owner has the right to transfer an ownership to others. An ITQ fishery management leads to both economic efficiency and resource conservation. Motivations to overexploit stocks and to overcapitalize should be lessened because fishermen no longer have to compete for limited resources. There are significant positive net benefits and advantages with ITQ fishery management than without. The potential benefits and advantages of ITQ fishery management include increased profits, economic stability, improved product quality, safer working conditions, less gear conflict, elimination of the race - to - fish phenomenon, less by - catch, less gear loss, improved investment climate, mitigation of market gluts, waste reduction, addition to fisherman's wealth, and compensation for fisherman exiting the fishery. As an independent observe to Red Crab Trap Fishery some of the benefits, problems, and effects, an ITQ fishery management in Red Crab Trap Fishery is still far from to be implemented. Many different and difficult aspects (biological, socioeconomics, administrative) are involved considering the implementation of ITQ fishery management in Red Crab Trap Fishery. Among other fishery management tools, the implementation of ITQ fishery management in Red Crab Trap Fishery is considered to be the best in achieving the better conservation of fisheries resources and their more economic and rational exploitation. Korean fisheries authority should pay great attention to the experience of the economic effects of the ITQ fishery management in Red Crab Trap Fishery in the hope of being able to implement at least some of those experiences into the Korean fishery management.

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Bio-sensing Data Synchronization for Peer-to-Peer Smart Watch Systems (피어-투-피어 스마트워치 시스템을 위한 바이오 센싱 데이터 동기화)

  • LEE, Tae-Gyu
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.4
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    • pp.813-818
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    • 2020
  • Recently, with the rapid increase in technology and users of smart devices, the smart watch market has grown, and its utility and usability are continuously expanding. The strengths of smartwatches are wearable portability, application immediacy, data diversity and real-time capability. Despite these strengths, smartwatches have limitations such as battery limitations, display and user interface size limitations, and memory limitations. In addition, there is a need to supplement developers and standard devices, operating system standard models, and killer application modules. In particular, monitoring and application of user's biometric information is becoming a major service for smart watches. The biometric information of such a smart watch generates a large amount of data in real time. In order to advance the biometric information service, stable peer-to-peer transmission of sensing data to a remote smartphone or local server storage must be performed. We propose a synchronization method to ensure wireless remote peer-to-peer transmission stability in a smart watch system. We design a wireless peer-to-peer transmission process based on this synchronization method, analyze asynchronous transmission process and proposed synchronous transmission process, and propose a transmission efficiency method according to an increase in transmission amount.

Fabrication of suction denture by using the individual tray duplicated an existing denture through scan and milling process: A case report (스캔 및 밀링을 통해 기존 의치를 복제한 개인트레이를 이용한 흡착식 의치 제작 증례)

  • Park, Minhyuk;Kee, Wonjin;Yang, Hongso;Park, Sang-Won;Yun, Kwi-Dug;Park, Chan
    • The Journal of Korean Academy of Prosthodontics
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    • v.58 no.3
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    • pp.221-227
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    • 2020
  • In the case of complete edentulous patients, as the mandibular alveolar bone absorption progresses, the maintenance and stability of the existing dentures, which had satisfactory functions in the past, are deteriorated. Despite of the need to fabricate new dentures, they often hesitate due to physical burdens on the duration and intensity of future treatment progress due to the effects of aging and systemic diseases. In the case of these completely edentulous patients, it is necessary to consider the treatment goals that can reduce the number of visits and the adaptation period for new dentures before starting the treatment. This case is a case of producing complete dentures of elderly patients with deteriorated physical ability. In addition to producing suction dentures through preliminary and definitive closed mouth functional impression suggested by Sato, CAD / CAM technique was used to transfer occlusal functional information of existing dentures to facilitate adaptation to new dentures.

Facile Synthesis of In2S3 Modified Ag3PO4 Nanocomposites with Improved Photoelectrochemical Properties and Stabilities

  • Zeng, Yi-Kai;Bo, Shenyu;Wang, Jun-hui;Cui, Bin;Gu, Hao;Zhu, Lei;Oh, Won-Chun
    • Korean Journal of Materials Research
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    • v.30 no.11
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    • pp.601-608
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    • 2020
  • In this work, Ag3PO4/In2S3 nanocomposites with low loading of In2S3 (5-15 wt %) are fabricated by two step chemical precipitation approach. The microstructure, composition and improved photoelectrochemical properties of the as-prepared composites are studied by X-ray diffraction pattern (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), photocurrent density, EIS and amperometric i-t curve analysis. It is found that most of In2S3 nanoparticles are deposited on the surfaces of Ag3PO4. The as-prepared Ag3PO4/In2S3 composite (10 wt%) is selected and investigated by SEM and TEM, which exhibits special morphology consisting of lager size substrate (Ag3PO4), particles and some nanosheets (In2S3). The introduction of In2S3 is effective at improving the charge separation and transfer efficiency of Ag3PO4/In2S3, resulting in an enhancement of photoelectric behavior. The origin of the enhanced photoelectrochemical activity of the In2S3-modified Ag3PO4 may be due to the improved charge separation, photocurrent stability and oriented electrons transport pathways in environment and energy applications.