• 제목/요약/키워드: specific field

검색결과 3,177건 처리시간 0.029초

Verification and Mitigation of Seismic Failure in Concrete Piers under Near-field Earthquakes

  • Ikeda, Shoji;Hayashi, Kazuhiko;Naganuma, Toshihiko
    • Journal of the Earthquake Engineering Society of Korea
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    • 제11권4호
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    • pp.1-11
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    • 2007
  • This paper verifies the difference of the seismic behavior and seismic damage of the neighboring two reinforced concrete piers damaged by the 1995 Hyogoken Nanbu earthquake. The two piers were almost the same size, carrying slightly different dead load, and were provided with the same reinforcement arrangement except the amount of longitudinal reinforcement at the bottom portion of the piers. The pier with more reinforcement was completely collapsed due to this near field earthquake by shear failure at the longitudinal reinforcement cut-off while the other was only damaged at the bottom by flexure even though the longitudinal reinforcement cut-off was also existed at the mid height of the pier. According to the results of the pseudo dynamic test, the seismic damage was recognized to be greatly dependent on the ground motion characteristics even though the employed ground motions had the same peak acceleration. The severe damage was observed when the test employed the seismic wave that had strong influence to the longer period range compared to the initial natural period of the pier. On the other hand, based on the similar model experiment, the defect of gas-pressure welded splice of longitudinal reinforcement was revealed to save the piers against collapse due to the so-called fail-safe mechanism contrary to the intuitive opinion of some researchers. It was concluded that the primary cause of the collapse of the pier was the extremely strong intensity and peculiar characteristics of the earthquake motion according to both the site-specific and the structure-specific effects.

Influence of Sensor Noise on the Localization Error in Multichannel SQUID Gradiometer System (다채널 스퀴드 미분계에서 센서 잡음이 위치추정 오차에 미치는 영향)

  • 김기웅;이용호;권혁찬;김진목;정용석;강찬석;김인선;박용기;이순걸
    • Progress in Superconductivity
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    • 제5권2호
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    • pp.98-104
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    • 2004
  • We analyzed a noise-sensitivity profile of a specific SQUID sensor system for the localization of brain activity. The location of a neuromagnetic current source is estimated from the recording of spatially distributed SQUID sensors. According to the specific arrangement of the sensors, each site in the source space has different sensitivity, that is, the difference in the lead field vectors. Conversely, channel noises on each sensor will give a different amount of the estimation error to each of the source sites. e.g., a distant source site from the sensor system has a small lead-field vector in magnitude and low sensitivity. However, when we solve the inverse problem from the recorded sensor data, we use the inverse of the lead-field vector that is rather large, which results in an overestimated noise power on the site. Especially, the spatial sensitivity profile of a gradiometer system measuring tangential fields is much more complex than a radial magnetometer system. This is one of the causes to make the solutions of inverse problems unstable on intervening of the sensor noise. In this study, in order to improve the localization accuracy, we calculated the noise-sensitivity profile of our 40-channel planar SQUID gradiometer system, and applied it as a normalization weight factor to the source localization using synthetic aperture magnetometry.

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Interregional Network Analysis of National Innovation Activities (국가 기술혁신활동의 지역 간 네트워크에 관한 연구 : 전기소자 기술을 중심으로)

  • Yoo, Sun-Hi
    • Journal of Information Management
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    • 제37권2호
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    • pp.93-107
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    • 2006
  • There are some questions about the way to monitoring the regional innovative activities in a specific field because of decision-making for raising regional specialized industry. Numerous studies have been conducted in the past using patent statistics to explain and compare the innovative capabilities of districts, regions and countries. The prior method of calculating the regional distribution of patent counts is to assign the patents to districts by assignee's address, which was not proper, in the case of larger firms's headquarters, holdings or subsidiaries, to mislead in geographical terms. So the regional distribution of patent was counted for a specific technology area, electric device field(H01 IPC classification), by inventors' residential addresses. Then the interregional structure was investigated by analysing the relations of co-inventors' regions by individual patent using a network analysis tool.

Field evaluation of Enterotoxigenic Escherichia coli-specific bacteriophage (ΦCJ19) as a feed additive (Enterotoxigenic Escherichia coli 특이 박테리오파지 (ΦCJ19)의 사료 첨가제로서의 사양 평가)

  • Yoo, Anna;Cha, Seung Bin;Shin, Min Kyoung;Park, Hong Tae;Seo, Hyo Sil;Kim, Jae Won;Yoo, Han Sang
    • Korean Journal of Veterinary Research
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    • 제53권2호
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    • pp.83-88
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    • 2013
  • Field efficacy of enterotoxigenic Escherichia coli-specific phage (${\Phi}CJ19$) as a feed additive was evaluated in weaning piglets. Fifty-four piglets at 3-4 weeks old were allocated in three different groups and two of them were fed with bacteriophage at different concentrations ($10^6PFU/kg$ feed and $10^8PFU/kg$ feed, respectively) for 30 days. Body weight and feed intake were measured at 10 days interval and body condition and fecal score were inspected every day. Based on the measurement, feed conversion rate (FCR) and average daily gain (ADG) of each group during 30 days were analyzed. The analysis suggests that the bacteriophage may help the improvement of FCR and ADG at $10^8PFU/kg$ of bacteriophage feeding group in 30 days. A result from analysis of fecal score indicates that the bacteriophage also may help to relieve the intermittent diarrhea in post-weaning stage. Those results suggest that bacteriophage might help the growth of piglets in post-weaning stage.

Educational Need Assessment of Advanced Practice Nurses on the Pathophysiology ("병태생리학" 교과목에 대한 전문간호사의 교육 요구도 조사)

  • Park, Mi-Jung;An, Gyeong-Ju;Jeong, Jae-Sim;Kim, Hee-Seung;Hong, Hae-Sook;Choe, Myoung-Ae
    • Journal of Korean Biological Nursing Science
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    • 제9권1호
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    • pp.85-102
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    • 2007
  • Purpose: Knowledge on pathophysiology is important to understand diseases and patient conditions and also in providing advanced nursing care. This study was performed to investigate the present situation, knowledge, and educational need on pathophyiology of advanced practice nurses(APN). Method: Eighty-four APN, who is practicing in hospitals nationwide, were surveyed with structured questionnaires developed by researchers. The questionnaire were composed of 109 items with 4 point scales with the contents of general characteristics, educational experience on pathophyisology, educational need, and knowledge on major and subcategories of pathophysiology. Result: The 77.1% of APN had experience of taking pathophysiology lecture and the lecturer were mainly medical doctors(39.8%) and APN(32.4%). The 61.5% of APN answered that the knowledge on pathophysiology was helpful and 97.6% of APN thought pathphysiologic education is needed in clinical practice. Seven major categories of pathophysiology showed higher scores were water imbalance, heart diseases, hemodynamic disorders, arterial vessel disorders, electrolyte imbalance, diseases of the digestive system, and diseases of the respiratory systems. Educational needs on the major and subcategories of pathphysiology were different by the field of APN and also by the clinical experiences as APN. APN also responded that there is a necessity to change the present curricular more specific to each practice field and more focus on the clinical practice. Conclusion: It was confirmed that educational and clinical need on the pathophysiology is very high and there is urgent need to change current curricular more specific to the field of APN and also clinical practice. This survey will help to identify and clarify the areas of change and to improve the education for the APN.

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Electronic Detection of Biomarkers by Si Field-Effect Transistor from Undiluted Sample Solutions with High Ionic Strengths

  • Ah, Chil-Seong;Kim, An-Soon;Kim, Wan-Joong;Park, Chan-Woo;Ahn, Chang-Geun;Yang, Jong-Heon;Baek, In-Bok;Kim, Tae-Youb;Sung, Gun-Yong
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1561-1567
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    • 2010
  • In this study, we have developed a new detection method using Si field effect transistor (FET)-type biosensors, which enables the direct monitoring of antigen-antibody binding within very high-ionic-strength solutions such as 1$\times$PBS and human serum. In the new method, as no additional dilution or desalting processes are required, the FET-type biosensors can be more suitable for ultrasensitive and real-time analysis of raw sample solutions. The new detection scheme is based on the observation that the strength of antigen-antibody-specific binding is significantly influenced by the ionic strength of the reaction solutions. For a prostate specific antigen (PSA), in some conditions, the binding reaction between PSA and anti-PSA in a low-ionic strength reaction solution such as 10 ${\mu}M$ phosphate buffer is weak (reversible), while that in high-ionic strength reaction solutions such as 1$\times$PBS or human serum is strong.

SAR in a Human Head Depending on the Arrangement of Antenna of Mobile Phone (이동통신단말기 안테나 배치에 따른 두부의 전자파 흡수율)

  • 이애경;김진석;이광천;조광윤
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • 제10권7호
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    • pp.1095-1103
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    • 1999
  • Presently, the retractable phone with a whip antenna composed of a helix and a monopole is most widely used for cellular mobile communications. However, since the length of the monopole is usually about λ/4, the strong radiated electric fields are produced in the region where the auricle of a head is contacted directly. This field distribution results in high specific absorption rates(SAR's) in the head. In this paper, SAR distributions and local SAR values for the inversely shaped phone(ISP) whose antenna arrangement is opposite to the original retractable phone(ORP) are compared with those for the ORP. This phone is accomplished by mounting the $\lambda$/4-whip antenna on the bottom, not on the top of the handset. The time-averaged field distribution in a computational space including a human model and a phone model is computed using the finite-difference time-domain(FDTD) method. SAR distributions and local SAR values for these phones are calculated with the field distributions. An anatomical head model and an approximate hand model were used to consider a real situation. From the analyzed data, it is shown that this arrangement of the antenna considerably reduces the spatial peak SAR in a human head.

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Conceptual Design of an HTS Motor for Future Electric Aircraft (차세대 전기 항공기를 위한 HTS 모터의 개념 설계)

  • Le, Dinh-Vuong;Nam, Gi-Dong;Lee, Seok-Ju;Park, Minwon
    • Journal of Korea Society of Industrial Information Systems
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    • 제25권5호
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    • pp.49-57
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    • 2020
  • Conventional electric motors are not suitable for aircraft because of their large size and weight. High-temperature superconducting (HTS) motors have high current density, high magnetic field density, and low loss, so they can significantly reduce the size and weight compared to general electric motors. This paper presents the conceptual design and analysis results of HTS motors for electric propulsion in future aircraft. A 2.5 MW HTS motor with a rotational speed of 7,200 RPM was designed and the specific power (kW/kg) was analyzed. The operating temperature of the field coil of the HTS motor is 20K in consideration of LH2 cooling. The stator winding were connected in a multi-phase configuration and Litz wires were used to minimize eddy current losses. As a result, it was confirmed that the specific power of the motor is about 18.67 kW/kg, which is much higher than that of the conventional electric motor.

Analysis of Educational System and Workforce Development Needs for Urban Air Mobility in Daegu-Gyeongbuk (대구경북지역 도심항공교통의 교육 체계 및 인력 양성 수요에 대한 분석)

  • Wooram Lee
    • The Journal of the Convergence on Culture Technology
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    • 제10권4호
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    • pp.701-710
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    • 2024
  • This study conducted a survey of companies in the aviation, drone, and Urban Air Mobility (UAM) sectors to analyze the educational and workforce needs, identifying essential competencies and technical training required. The study also proposed potential areas for collaboration between universities and industry regarding educational methods. Key findings and implications of the survey were derived. The results indicated that the most critical consideration for hiring was job-specific skills in the respective field. The most essential quality for workforce training was identified as enhancing the ability to use various equipment and software related to the major field. In the UAM sector, there was a high demand for personnel and education related to aircraft and components, with the highest demand being for lightweight manufacturing technology for aircraft. This study can serve as foundational data for addressing the educational needs in this field.

A Study on the Establishment of Clinical Nurse Specialist (우리나라 전문간호사제도 개선방안에 관한 연구)

  • Byun, Young-Soon;Kim, Young-Im;Song, Mi-Sook
    • Research in Community and Public Health Nursing
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    • 제5권2호
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    • pp.130-146
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    • 1994
  • Our medical care system is trying to diversify in order to meet the client's needs, and to adjust to a medical environment which is changing very rapidly. Because current nursing theory and practice focus on holistic care, health care management, education, and research, contrary to the traditional emphasis on only assisting a physician, more autonomy and specialization for the implementation of nursing are required. Considering these trends and actual needs, the category of clinical nurse specialist should be established as soon as possible. In order to develop strategies for implementing this new professional specialty, the authors conducted a field survey and literature review of the current system in Korea. As a result, various obstacles and constraints were discovered as follows : 1) There are few accredited educational programs for the training of CNS's. 2) Several hospitals already have staff designated as clinical nurse specialist (CNS) even though the term CNS is not yet standardized or adopted in nationwide. 3) The role of the CNS is not clearly understood by the medical societies, or even nursing societies. A nurse who works in specific nursing areas such as central supply, kidney dialysis, intensive care, coronary care, etc. for a long time, considers herself /himself a CNS. Based upon the above findings, the following alternatives are recommended. 1) The role of the CNS should be defined according to specified functions and authority : professional autonomy ; counselling and educating patients and their familes, nurses, and even other medical personnel ; research on improvement of nursing ; and management of the nursing environment including medical resources, information, and cases. 2) the qualification of CNS should be attained only by a nurse who has an RN license and clinical experience of more than 3 years in a specific nursing field: passes a qualifying examination; and contributes to the professional development of peers, colleagues, and others. A master's degree should only be optional, because of the insufficient of graduate programs which are well designed for the CNS. 3) The CNS should initially be a head nurse rather than line staff in order to deal with as wide an experience base as possible. 4) The nursing specialty could be divided into two areas such as a clinical field and a community field. The clinical field could then be categorized by the Styles' classification such as diseases and pathogenics, systems, ages, acuity, skills/techniques, and function/role ; the community field could be classified according to work site.

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