• 한국정밀공학회지
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• 제32권11호
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• pp.983-988
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• 2015

This paper details a new ultra-precise turning method for increasing surface quality, "Multi Point B Axis Control Method." Machined surface error is minimized by the compensation machining process, but the process leaves residual chip marks and surface roughness. This phenomenon is unavoidable in the diamond turning process using existing machining methods. However, Multi Point B axis control uses a small angle (< $1^{\circ}$) for the unused diamond edge for generation of ultra-fine surfaces; no machining chipping occurs. It is achieved by compensated surface profiling via alignment of the tool radial center on the center of the B axis rotation table. Experimental results show that a diamond turned surface using the Multi Point B axis control method achieved P-V $0.1{\mu}m$ and Ra 1.1nm and these ultra-fine surface qualities are reproducible.

• 대한물리의학회지
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• 제5권4호
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• pp.685-692
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• 2010

Purpose : The purpose of this study was to investigate effects of repetitive hand task on upper extremity proprioception and dexterity. Methods : Experimental group who had done hand task since last 1 year and young adult control group was recruited this study. Proprioception was measured positioning errors of elbow and wrist on three dimensional coordinate system by Winarm software(Zebris Medcal GmbH, Germany). And dexterity was measured by box and block test. Statistical analysis was used independent t -test. Results : When elbow moved from flexion to extension, there were significant difference on error of x axis in wrist location and erros of x, z axis in shoulder location(p<.05). When wrist moved from flexion to extension, there was significant difference on y axis in finger location error(p<.05). And there significant difference on dexterity(p<.05). Conclusion : In conclusion, repetitive hand task increase upper extremity proprioception and dexterity. The physical therapy in industrial workers should inhibit overuse injury.

• 한국방사선학회논문지
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• 제15권3호
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• pp.321-327
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• 2021

Wrist PA-grip view는 주변 인대들의 손상을 쉽게 진단할 수 있기 때문에 삼각섬유연골 파열 진단에 시행한다. 그러나 의료장비 기술의 발전에도 불구하고 기하학적 요소에 따른 영상의 왜곡은 아직까지도 많은 제한점이 있다. 본 논문에서는 정확한 Wrist PA-grip view 검사를 위해 현재 사용되고 있는 검사방법에서 발생되는 왜곡을 분석하여 영상의 왜곡을 최소한으로 감소시킬 수 있는 검사방법을 제시하고자 한다. Wrist PA-grip view를 재현하기 위하여 인체모형 팬텀을 사용하였고 source of image distance (SID)는 110 cm와 임의로 정해놓은 130 cm, 150 cm로 설정하였다. 각 SID에 따라서 손목 팬텀을 x축 방향 및 y축 방향으로 각각 0, 2, 4, 6, 8, 10 cm 이동하였다. 정량적 평가를 하기 위해 손목 팬텀의 이동 시 마다 자뼈와 노뼈의 먼쪽관절면의 거리의 차이를 picture archiving and communication system (PACS) system을 통해 측정하였다. 정성적 평가로는 방사선사 20명을 대상으로 설문조사를 실시하였다. SID에 따라 나뉜 세 그룹 간의 x축과 y축 방향의 움직임에 따른 왜곡도를 비교하기 위해 Kruskal Wallis test 통계기법을 시행하였으며 사후검정으로 Tukey test를 시행하였다. 정량적 평가 결과에서 x축 방향으로 이동하여 얻은 측정값은 모든 그룹에서 유의한 차이를 보이지 않았다 (p>0.05). y축 방향으로 이동하여 얻은 측정값은 대부분의 그룹에서 유의한 차이를 보였다 (p<0.05). 영상에서 왜곡이 임상적 진단과 수술에 많은 영향을 미치는 검사의 경우, 보다 정확한 진단을 위해 영상 후처리로 영상의 질을 유지하는 한도 내에서 기존의 SID인 110 cm 보다는 150 cm에서 검사하여 왜곡을 감소시키기를 제안하는 바이다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제28권1호
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• pp.4-13
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• 2017

The seeds of addiction are typically sown years prior to the onset of addictive substance use or engagement in addictive behaviors, due to the priming of the reward pathway (RewP) by alterations in the mechanism of stress-signaling from the hypothalamic-pituitary-adrenal axis (HPA) and related pathways. Excessive stress from a single-event and/or cumulative life experiences during childhood, such as those documented in the Adverse Childhood Experiences Study, is translated into neurobiological toxicity that alters the set-point of the HPA axis and limbic system homeostasis [suggested new term: regulation pathway (RegP)]. The resultant alteration of the RegP not only increases the risk for psychiatric and physical illness, but also that for early onset and chronic addictions by dysregulating the RewP. This paper reviews the interface of these symbiotic pathways that result in the phenotypic pathology of emotional dysregulation, cognitive impairment, and compulsive behaviors, as well as morbidity and shorter life expectancy when dysregulated by chronic stress.

• ALGAE
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• 제22권2호
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• pp.87-93
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• 2007

Three ecotypes of the freshwater red alga Compsopogon coeruleus (Balbis) Montagne were recorded from different freshwater and brackish water habitats of Orissa state in the east coast of India. These three had persistent differences in their branching pattern, e.g. (i) acute angle between main axis and lateral branch, (ii) equal or near to right angle between main axis and lateral branch, and (iii) short spine-like outgrowth instead of a branch in older filaments, besides having differences in the length, breadth and thickness of cortex of the thallus. Morphological observation of these taxa, and the ecological characteristics of the habitat of their occurrence is presented.

• Steel and Composite Structures
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• 제27권3호
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• pp.337-353
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• 2018

In previous weak-axis moment connection tests, brittle fracture always initiated near the edge of the beam flange groove weld due to force flow towards the stiffer column flanges, which is the opposite pattern as strong-axis moment connections. As part of the China NSFC (51278061) study, this paper tested two full-scale novel weak-axis reduced beam section moment connections, including one exterior frame connection specimen SJ-1 under beam end monotonic loading and one interior frame joint specimen SJ-2 under column top cyclic loading. Test results showed that these two specimens were able to satisfy the demands of FEMA-267 (1995) or ANSI/AISC 341-10 (2010) without experiencing brittle fracture. A parametric analysis using the finite element software ABAQUS was carried out to better understand the cyclic performance of the novel weak-axis reduced beam section moment connections, and the influence of the distance between skin plate and reduced beam section, a, the length of the reduced beam section, b, and the cutting depth of the reduced beam section, c, on the cyclic performance was analyzed. It was found that increasing three parametric values reasonably is beneficial to forming beam plastic hinges, and increasing the parameter a is conducive to reducing stress concentration of beam flange groove welds while increasing the parameters b and c can only reduce the peak stress of beam flange groove welds. The rules recommended by FEMA350 (2000) are suitable for designing the proposed weak-axis RBS moment connection, and a proven calculation formulation is given to determine the thickness of skin plate, the key components in the proposed weak-axis connections. Based on the experimental and numerical results, a design procedure for the proposed weak-axis RBS moment connections was developed.

• 한국산학기술학회논문지
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• 제11권10호
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• pp.3789-3793
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• 2010

검영기 훈련 모형안(모형안)에 표시된 굴절상태 눈금과 벗어난 시축의 효과를 타각적 굴절검사인 검영법으로 알아보자 하였다. 두 명의 능숙한 retinoscopist가 검영법을 이용하여 굴절상태를 무작위로 검사하였다. 동일한 7개의 훈련 모형안을 선정하여 각각 +4에서 -6 diopter(+4, +3, +2, +1, 0, -1, -2, -3, -4, -5, -6) 굴절상태 눈금을 맞추고 거리보정용 시험렌즈를 가입하여 180도 경선에서 중화거리를 측정하여 눈금설정 상태를 평가하였고, 시축과 5, 10, 15, 20도 시축에서 벗어난 굴절력을 측정하였다. 두 명의 retinoscopist가 측정한 눈금설정 상태는 7개 중 6개의 훈련 모형안 이 통계적인 차이가 있었다(P<0.05). 5, 10, 15, 20도 시축에서 벗어난 검영법 굴절력은 $-0.13{\pm}0.06$, $-0.29{\pm}0.06$, $-0.58{\pm}0.11$, $-0.83{\pm}0.16$ diopter 이였다. 모형안에 표시된 굴절상태 눈금과 검영법을 이용하여 측정한 굴절상태 눈금이 다를 수 있고, 모형안에 검영을 시축에 벗어나 시행할 경우 굴절 검사값에 오차를 유발할 수 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1316-1319
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• 1996

This paper proposes the algorithm for the correction of a position and orientation of small object such as chip in the precise construction process. In the past, it is general to correct position and orientation of object using human sight and simple vision sensors. But recently, researches using image processing devices have been studied to improve the corrective precision of a position and orientation of object. In this piper, maximum-axis moment and p-theta algorithm are used to correct the position and orientation. Algorithm of maximum-axis moment is widely applied to hetero-object except being applied to a perfect rectangle. This is reason that moments of the X and Y-axis are equal. Therefore, being the shape of a perfect rectangle, the object is applied to other algorithm. In the light of time problem, real-time control is as important as correction of object. To solve it, we use the DSP(Digital Signal Processing) which is far more fast than PC.

• Journal of Biosystems Engineering
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• 제24권1호
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• pp.41-50
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• 1999

This study aims at detecting the three dimensional gripping points for the transplanting robot system to grip in the process of developing transplanting robot system, which is one of the automation systems for transplanting tissue culture. The stereo vision system equipped with two cameras has been used to detect the gripping points of the plant stem. The method for matching the plants of the image information which came from two cameras was to measure the total numbers of pixels, leaves, and the heights of the plants. The gripping points were detected near the roots after extracting the stem parts by the standard deviation of the X axis according to the Y axis. The performance test of the developed program showed that the detecting errors of the gripping points were 0∼1mm for X axis and 1∼2mm for Y & Z axis. The mean running time of the program was about 3 seconds.

• Applied Biological Chemistry
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• 제27권2호
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• pp.129-134
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• 1984

콩나물을 온도별로 길러 생장과정별 단백질조성을 7.5% polyacryl amide gel 전기영동법으로 조사하고 조제표품단백질의 그것으로 동정하였다. 원료대두(大豆)에서는 주(主) band 5개(a,b,c,d 및 p)와 미소 band 10개가 나타났고 4일자자엽(日字子葉)에서는 8개의 주(主) band와 (o band포함)와 11개 미소 band로 최고 band수(數)를 보였다. 배축(胚軸)에서는 자엽(子葉)에서 발견(發見)되는 band들이 모두 나타났으나 분리(分離)가 선명치 못하였다. 생육이 경과함에 따라 자엽(子葉)에서는 a band가 먼저, b,c,d band가 다음으로 감소해 갔으며 미소 band o+p는 6일(日)까지 증가하다 그후 감소하였다. 배축(胚軸)에서는 모든 band가 계속 증가하였는데 미소 band와 b+c+d가 증가속도가 컸다. a band는 7S, b+c+d는 11S, o+p는 2S globulin으로 동정되었다. 생육온도가 높아짐에 따라 자엽(子葉)에서의 감소와 배축(胚軸)에서의 증가속도가 빨라졌으며 7S보다 11S가 촉진되었다.