• 제목/요약/키워드: joint characteristics

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공동 특허 출원인간 협력 요인이 기술혁신성과에 미치는 영향 분석: 우리나라 정보통신업을 중심으로 (Study of the Effects of Co-Patent Network Factors on Technological Innovation: Focus on IT industry in Korea)

  • 주성환;서환주
    • 기술혁신연구
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    • 제25권4호
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    • pp.211-238
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    • 2017
  • 본 연구는 혁신주체 간 협력이 기술혁신 성과에 미치는 영향을 알아보기 위해 사회네트워크분석 및 분산분석 그리고 회귀분석을 실시하였다. 2009년부터 2012년까지 한국 특허청의 공동 출원인 자료를 토대로 네트워크 구조 변수 및 특성 변수를 도출하였다. 이를 통해 전체 네트워크의 구조적 유형, 혁신주체 별 역할 그리고 혁신 성과에 영향을 미치는 네트워크 특성 변수가 무엇인지를 실증 분석하였다. 분석결과를 요약하면 다음과 같다. 첫째, 특허 공동출원인 네트워크는 비교적 소규모 그룹들이 산재해 있는 분산집중형 좁은세상 네트워크 구조이며 혁신주체들이 비교적 느슨하게 연결되어 있었다. 둘째, 특허 공동출원인 네트워크에서 가장 중심적인 역할을 하는 것은 대학교로 밝혀졌으나 협력 파트너의 다양성은 모든 혁신주체가 비슷하였다. 셋째, 익숙한 몇몇 협력 파트너로부터 얻는 신속하고 정확성이 높은 지식이 다양한 분야의 협력 파트너로부터 얻는 생소한 지식보다 성과를 창출하는 데에 보다 긍정적이었다.

무기체계 획득관리의 최적화 (I) -무기체계 획득시스템의 선정을 위한 비용대효과분석모형을 중심으로- (The Optimal Process of Weapon Acquisition Management (I) -With Special Reference to the Cost/Effectiveness Model for the Selection of Weapon Acquisition System-)

  • 이진주;권태영;주남연
    • 한국국방경영분석학회지
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    • 제3권2호
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    • pp.49-77
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    • 1977
  • Weapon systems are curcial instruments for the security of a nation and critical elements for the victory in a war. Since modern weapon systems tend to be capital-intensive with high precision and quality, they become more and more complex and diversified; their acquisition costs become huge; and their technological obsolescence becomes accelerated. Therefore, the systematic management of weapon acquisition process would be one of the most important defense tasks at the national level. To analyze such problems and find solutions, this paper has studied various aspects related to the efficient management of weapon system acquisition. After brief summarization of the general characteristics of weapon systems, their effectiveness, and developmental trend, the paper discusses the defense management policies and techniques for the weapon systems. Specifically, four alternative acquisition methods such as indigenous R & D, foreign purchase, co-production and joint-production are discussed and analyzed by systems approach. The systems analysis procedure to evaluate and select weapon acquisition method is as follows; 1) to analyze the merits and demerits of the alternative methods, 2) to screen unrealistic alternatives through the consideration of significant factors such as political, economic, military, technological, and social constraints, 3) to evaluate and select an optimal one among the remaining acquisition methods after the cost-effectivenss analysis. For the base of cost-effectivess analysis, cost analysis model as well as effectiveness analysis model of each acquisition method are developed.

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서해에서 측정된 수중 주변 소음의 공간 코히런스 분석 (Spatial Coherence Analysis of Underwater Ambient Noise Measured at the Yellow Sea)

  • 권혁종;김정훈;최지웅;강돈혁;조성호;정섬규;박경주
    • 한국음향학회지
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    • 제34권6호
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    • pp.432-443
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    • 2015
  • 코히런스 분석은 두 수신신호의 유사성을 분석하는 방법으로, 수중음향에서는 음파의 시간 및 공간 특성을 나타낼 수 있는 유용한 분석 방법이다. 본 논문에서는 한국해양과학기술원과 한양대학교가 공동으로 수행한 해양음향 실험의 일부로, 3개의 수중청음기로 구성된 수직선배열센서를 이용하여 수중에서 주변 소음을 측정하였다. 조사선 발전기가 작동할 때와 정지했을 때, 총 두 가지 경우에 대하여 주변 소음이 측정되었고 각각에 대한 코히런스 분석을 수행하였다. 조사선 발전기가 작동하는 경우의 코히런스 결과는 조사선 발전기 소음의 전달 손실을 고려하여 계산된 방향 밀도함수를 이용한 코히런스 결과와 비교되며, 조사선 발전기가 정지한 경우인 주변 소음의 코히런스 결과는 해수면 소음원, 해저면 구성성분 및 원거리 선박 소음이 반영된 코히런스 모델 결과와 비교, 분석되어진다.

주짓수 선수의 허리 통증 유무에 따른 엉덩관절 돌림 가동범위 비교 (Comparison of Hip Rotation Range of Motion in Jiu-Jitsu Athletes With and Without Low Back Pain)

  • 양성준;박규남;경문수;김시현
    • 한국전문물리치료학회지
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    • 제25권1호
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    • pp.47-52
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    • 2018
  • Background: A limited hip rotational range of motion (ROM) has been considered to be one of characteristics of low back pain (LBP) in athletes. Although LBP frequently occurs in jiu-jitsu athletes, no previous has compared hip rotational ROM between jiu-jitsu athletes with and without LBP. Objects: The aim of the study was to compare ROM for hip internal rotation (IR) and external rotation (ER), and total hip rotation between jiu-jitsu athletes with and without LBP. Methods: Jiu-jitsu athletes were recruited for the LBP group ($n_1=15$) and control group without LBP ($n_2=15$). IR, ER, and total rotational range of hip joint were measured using a goniometer. Analysis of variance was used to compare the ROM between groups and sides. Results: The LBP group showed a significantly lower range of passive hip IR, passive total rotation, active IR, active ER, and active total rotation than the control group (p<.05). Dominant side of passive hip IR and active IR had a significantly lower ROM than non-dominant side (p<.05). In passive ER ROM, non-dominant side was significantly greater than dominant side (p<.05). Conclusion: Compared to jiu-jitsu athletes without LBP, athletes with LBP exhibit a loss of hip rotational ROM. Based on these results, clinicians and athletic trainers should measure hip rotational ROM when designing the management plan for jiu-jitsu athletes with LBP.

Scar Status, Depression, Sleep, and Health Related Quality of Life Following Severe Burn Injury: A Cross-sectional Descriptive Study

  • 오현진;김경자;서정훈;김도헌;이병철;부선주
    • 가정∙방문간호학회지
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    • 제26권3호
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    • pp.341-348
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    • 2019
  • Purpose: Severe burn injuries require long periods of hospitalization and treatment, which results in various physical and psychological issues. The main purpose of this study was to identify burn characteristics and psychological problems that influence Health Related Quality of Life (HRQoL) after discharge. Methods: A cross-sectional descriptive study using mobile/web or paper-based survey methods was conducted from a major burn center. A total of 145 patients completed the scar assessment, quality of life, sleep disorders, and depression scales. Results: The overall mean HRQoL and scar status scores were 2.28 out of 5 and 34.45 out of 60 points, respectively. Participants with higher burn degree, joint involvement, and emotional distress reported significantly lower HRQoL and scar status. Participants with depression and sleep problems also had lower HRQoL. Significant predictors of HRQoL included burn range, scar status, depression, and sleep issues. Conclusion: The results show that patients with severe burn injury experience high levels of physical and psychological problems. Patients with severe burn injury and psychological problems such as depression and sleep are likely to experience a reduced HRQoL. Psychological management and intervention in home care setting may improve HRQoL of burn patients.

Ag-Pd 후막도체와 솔더범프 사이의 접합특성 및 계면반응 (Characteristics of Joint Between Ag-Pd Thick Film Conductor and Solder Bump and Interfacial Reaction)

  • 김경섭;한완옥;이종남;양택진
    • 마이크로전자및패키징학회지
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    • 제11권1호
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    • pp.1-6
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    • 2004
  • 자동차 전장품의 시험환경 조건이 엄격해짐에 따라, 전장품 개발 기술자들은 이에 부합하는 성능, 신뢰성, 비용 등을 고려한 보다 효과적인 제품 설계를 위해 노력하고 있다. 본 논문에서는 ECM 알루미나 기판의 플라즈마 세척 영향과 리플로우 후 Sn-37wt%Pb 솔더와 패드 접합부 계면에서 형성되는 금속간 화합물을 관찰하였다. 기판의 플라즈마 세척은 계면 접착력을 저해하였던 C에 의한 유기 잔류물 층이 제거되어 계면 접착력을 향상시키는 효과가 있다. 또한 AFM 분석 결과 도체 패드의 표면 거칠기는 304 nm에서 330 m로 증가하였다. 리플로우 과정에서 솔더와 TiWN/Cu 패드 계면에서 형성된 $Cu_6/Sn_5$는 리플로우 횟수가 증가할 수록 결정립의 크기도 조대화되었다. 솔더와 Ag-Pd 도체패드 계면에서는 세포질 형태의 $Ag_3Sn$화합물이 관찰되었다. $Ag_3Sn$은 지름이 약 0.1∼0.6 $\mu\textrm{m}$이며, 솔더 내부에서는 침상 모양도 관찰되었다.

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비내진설계된 우리나라 RC 외부 접합부의 횡저항 능력에 관한 실험 (Experiments of the Lateral Loading Capacity of Exterior Joints of Non-seismically Designed RC Frames in Korea)

  • 이영욱;박형권
    • 한국지진공학회논문집
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    • 제14권4호
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    • pp.29-36
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    • 2010
  • 국내 비내진 설계된 RC 골조 외부접합부의 횡저항 능력특성을 연구하기 위하여, 1988년 이후의 건물을 대상으로 실물 크기의 70%의 T형 보-기둥 실험체 4개를 제작하여 보에 횡력을 가력하여 실험을 수행하였다. 작용한 횡력은 총 9단계로 변위를 조절하여 최대 횡변위비 3.5%까지 가력하였고, 각 변위 단계마다 3싸이클의 반복하중을 가력하였다. 실제의 상황과 유사하게 하기 위하여 실험동안 기둥에 압축력을 지속적으로 작용하였다. 실험 결과, 부재가 휨 공칭강도에 도달하여야 하는 내력에 비하여 실험 결과는 85%이하로 나타났고 층간변위비 0.85% 미만에서 모든 실험체의 접합부에서 전단균열이 발생하여 국내 외부접합부가 취약함을 확인할 수 있었다. 또한 접합부 균열발생시 주응력-층간변위비는 Priestly의 제안식과 유사하게 나타났다.

대학생들의 생활습관이 시력에 미치는 영향에 관한 연구 - 치기공과 재학생을 중심으로 - (A Study on the Impact of Life Habits on Eyesight among College Students (centering on students studying Dental Technology))

  • 최운재;전정자
    • 대한치과기공학회지
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    • 제32권4호
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    • pp.403-415
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    • 2010
  • Purpose: The purpose of this study was to examine the eyesight and life habits of college students in an attempt to provide some information on the protection of their eyesight. Methods: The subjects in this study were 311 students in the department of dental technology at a college of health, on whom a survey was conducted. A crosstabulation analysis was carried out to show the joint distribution of general characteristics and several variables involving the use of glasses or contact lenses and life habits. Results: 77.5% of the students currently wore glasses due to weak sight. 9.3% took an eye test on a regular basis, and 31.2% did that every six months. As for the length of the length of daily mean reading time, 55.3% spent one hour or less reading books. The most common distance between eyes and books during their reading(44.7%) was 21 to 25. Concerning a reading posture, the biggest group(54.3%) lay down or lay on their face while they read books. 45.0 % spent less than an hour watching TV per day on average, and 27.0% were on the computer for 30 minutes to less than an hour per day on average. The greatest group(63.0%) made use of basic indoor lighting when they were on the computer at night, and 62.1% saw eye doctors to take an eye test. In relation to how to protect eyesight, the biggest group(50.5%) spent less time being on the computer. Conclusion: As the eyesight of college students fails due to reading, TV, computer, and improper ways and posture of doing or using those things, every college definitely should provide education on eye health as one of general education courses.

엄지 두덩 덩이로 발생한 근육내 신경섬유종 (An Intramuscular Neurofibroma Presenting as a Thenar Mass)

  • 강문석;최환준;남승민;이형교
    • Archives of Plastic Surgery
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    • 제38권1호
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    • pp.109-112
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    • 2011
  • Purpose: Neurofibromas may present as multiple or solitary lesions. Although there is no predilection site for solitary lesions, they are rare on the hand. In addition, solitary intramuscular neurofibromas are a very rare pathological type. Here, we report a rare solitary intramuscular neurofibroma in the hand. This paper examines the clinical characteristics of intramuscular neurofibroma arising from the lumbricalis in order to enable a correct diagnosis and treatment. Methods: A 32-year-old male presented with a painless mass on the palm. The physical examination revealed a $3{\times}2$ cm protruding mass that was non-tender to palpation. The vascular and sensory examinations were unremarkable, while the motor examination showed mild difficulty with flexion and extension. Magnetic resonance imaging demonstrated an enhancing solid mass between the thenar eminence and second metacarpophalangeal joint. The diagnosis of an intramuscular neurofibroma was confirmed following surgical excision and histological evaluation. Results: The pathological examination was consistent with a neurofibroma, with delicate fascicles and loose fusiform cells in a fibrous stroma, with oval or spindle-shaped nuclei and scant cytoplasm. The background matrix was pale staining and had focal myxoid stroma. There was no significant nuclear pleomorphism and no mitoses. Immunohistochemistry with S-100 was slightly positive. At the 6-month follow-up, motor and sensory function were intact and the range of motion was full. Conclusion: A neurofibroma is a rare tumor of the hand, especially the intramuscular type. Hand surgeons should consider the diagnosis of this tumor based on the examination and imaging.

편마비 환자의 반 무릎서기 자세가 일어서기 동작 수행에 미치는 영향 (Influence of Transition from the Half-Kneel to Standing Posture in Hemiplegic Patients)

  • 양대중;장일용;박승규;이준희;강정일;천동환
    • The Journal of Korean Physical Therapy
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    • 제23권5호
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    • pp.49-56
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    • 2011
  • Purpose: The purpose of this study was to investigate the kinematic characteristics and muscle activities during the following two conditions: transition from half-kneel to standing on the affected leg and non-affected leg. Methods: Twenty-one hemiplegic patients participated in the study. A motion analysis system was used to record the range of motion and angle velocity of the hip, knee and ankle from the half-kneel to the standing position. Electromyography was used to record the activity of 4 muscles. Results: The statistical analysis showed that the minimum ROM of the hip joint was less on the affected leg during transition from half-kneel to standing. However, the minimum ROM of the knee and ankle joints was less on the non-affected leg during transition from half-kneel to standing. The angle velocity of the knee and ankle joints was less during transition from half kneeling to standing on the non-affected leg. Muscle activity of the rectus femoris and tibialis anterior was less while moving from half-kneel to the standing position on the affected leg. Conclusion: These results show that greater active ROM of the knee and ankle was required on the affected leg for transition from half-kneel to the standing position than for normal gait. Muscle activity of the rectus femoris and tibialis anterior is normally required for movement from the half-kneel to the standing position during normal gait. Further studies are needed to investigate the antigravity movement in healthy subjects and hemiplegic patients in order to completely understand the normal and abnormal movement from the half-kneel to the standing position.