휴대폰 카메라용 자동초점 구동기의 충격해석

이성민,김봉석,송준호,이수훈,이혜진,이문구,송준엽,이창우 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

Recently, the robustness against daily impact is important according to portablization and downsizing of mobile electronics. Especially, almost parts of cellular phone should undergo drop test when they fall 1.5 m above ground. This test simulates the case when cellular phone slips through user's fingers while he is talking on the phone. This paper studies a drop test of auto focusing (AF) actuator for camera module in cellular phone. This component is composed of voice coil motor (VCM) as an actuator and leaf spring as a guide and suspension. The leaf spring's deformation is essential for the test because its permanent distortion disables the focusing, and then, a high quality photograph cannot be obtained. Up to now the drop test has been carried out after fabricating real AF actuator. We propose a dropt test model which simulates the drop test based on finite element analysis. This model makes us enable investigate the stress acting on the clamping and curved parts of leaf spring. Stress over Von Mises criterion lets the spring deformed permanently, and then AF actuator malfunctioned, It helps us to design and modify AF actuator without manufacturing the real product. And also, it saves the time and cost for the development of new products.

매크로/마이크로 레벨 볼트 결합 구조물에서의 실험적/해석적 방법을 통한 시스템 특성 비교

김봉석,이성민,이문구,이수훈,Jun Ni,송준엽,이창우,하태호 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

As the micro technology and miniaturization of a structure and component in the last couple of decades have been concretely realized, the understanding of structural and dynamic characteristics and prediction of dynamic behavior are indispensable to the miniaturized structures and micro machines. This paper shows the effect of dynamic characteristics in bolt-jointed structures by comparing natural frequencies and mode shapes between macro and micro-scale beams through experimental modal analysis and finite element analysis with a1 8 test models by materials, by size, and by joining condition; that is, SS41 and A16061-T651, micro and macro, and monolithic beam and bolt-jointed beam.

진동감쇠 장치를 부착한 트레일러의 수직진동

이홍주,홍종호,김성엽 한경대학교 2003 論文集 Vol.35 No.-

This study was aimed to find out the basic information for reducing damage of agricultural products during transportation. The vibration absorption system, consisted of suspension at wheel mounting and coil spring & rubber at hitch part, was developed and tested for the vibration characteristics. The vertical acceleration level was measured at 6 positions, i.e. engine, hitch, seat, and three parts of trailer(front, middle, and rear) according to the low(500rpm), medium(1000rpm), and high(1200rpm) engine speed. The results of this research could be summarized as follows; (1) For low engine speed of 500rpm, the average vertical accelerations were in the range of 0.11~0.27 m/s² by the sensing positions. The higher vertical accelerations were occurred at seat and front position of trailer in order. The vertical accelerations were distributed up to 100Hz at engine, hitch and trailer position, but were equally distributed up to 400Hz at seat position. At three positions of trailer, the peak accelerations of 0.3~1.0 m/s² was occurred one or two times. (2) For medium speed of 1000rpm, the average vertical accelerations were higher in low frequency range, but decreased in higher frequency range up to 300Hz at engine and hitch positions. The vertical accelerations were equally distributed up to 379Hz at seat position, but distributed up to 170Hz at trailer, and the peak accelerations of 0.8, 0.4, 0.2 m/s² were occurred one or two times at front, middle, and rear side of trailer, respectively. (3) For high speed of 1200rpm, the average vertical accelerations were equally distributed up to 400Hz at engine, hitch and seat positions, but up to 500Hz at trailer. The peak acceleration of 0.3m m/s² was occurred two or three times at trailer position. (4) For driving power tiller at speed of 0.35m/s on the controlled road, the peak vertical acceleration were occurred in the range of 80~150Hz at engine, hitch, and rear side of trailer position. The vertical accelerations were very low level for higher frequency range over 200Hz.

안성시 지역의 농업기계 보관관리 실태조사

이홍주,이성범,김성엽 안성산업대학교 1999 論文集 Vol.31 No.-

This study was conducted to analyze the storage and management status of major farm machinery, and to present the basic information for the construction of multipurpose storage housing suitable to the individual farmers by identifying current problems. The results of this study are summarized as follows; 1. The average farm area of the surveyed farmers was 4.25㏊, which represents relatively higher than the average of whole country. The mechanization rate for paddy farming was 98% so, the individual storage housing should be concentrated on the farm machinery utilized in paddy farming. 2. The annual operating span of the seasonal farm machinery (such as combine and rice transplanter) showed high difference between farmers and machines. For th rice transplanter, the highest portion of annual operation span was less than 10 days as 70%, and for the combine, that was over 20 days as 36% and the second was 16~20 days as 23%. The average difference in repairing cost for combine between the farmers with and without common storage housing was 100,000won. 3. The percent of storaging farm machinery in the open field for farmers without housing were 44% for power tiller, 16% for farm tractor, 21% rice transplanter, 10% for combine. Each farmer has individual temporary simple housing with various kinds and structure. 4. Most of the farmers, 63.7%, want to use the farm machinery storage housing for multipurpose utilization, 29% only for storaging purpose. Most farmers prefer near the farm house as suitable position of housing, and prefer the area of 132~198㎡ for storage housing. The current problems on common storage housing were insufficient area(44.8%), no problem(29%), improper position, excessive construction cost, inconvenient entrance, etc.

플로우(Flow)가 배너광고의 지각된 혼잡도와 광고태도에 미치는 영향 : 이용자의 주의에 따른 차별적 효과

이철선,유승엽 한국방송광고공사 2004 광고연구 Vol.0 No.63

인터넷에서는 많은 배너광고가 동시에 제시될 뿐만 아니라 브랜드들이 유사한 경우가 많다. 이는 광고의 지각된 혼잡도(perceived clutter)의 구성요인과 밀접한 관련성을 가진다. 그러나 인터넷은 쌍방향 커뮤니케이션이 가능하여 자신의 의사에 따라 선택적으로 광고를 회피하거나 볼 수 있는 매체이다. 따라서 본 연구에서는 인터넷 광고의 지각된 혼잡도를 포함한 광고효과를 반복적인 경험과정 측면에서 그리고 소비자의 통제권이라는 측면에서 살펴보고자 시도되었다. 먼저 본 연구에서는 인터넷 이용자의 주의의 대상에 따라 광고의 지각된 혼잡도와 광고태도에 직접 영향을 미치는 플로우의 역할과 방향성에 대한 연구가설을 설정하였다. 그리고 플로우가 지각된 혼잡도와 광고태도에 미치는 간접적인 경로에서 지각된 행동통제가 매개변수로 작용한다는 연구가설도 설정하였다. 특히 두 번째 경로는 플로우가 광고태도에 미치는 영향이 소비자의 통제권 하에서 이루어진다는 것을 설명하기 위함이었다. 분석결과, 지각된 혼잡도에 영향을 미치는 플로우에 대한 가설은 유의한 것으로 나타났다. 그리고 플로우가 광고태도에 미치는 영향에서 지각된 행동통제가 중요한 매개변수로 작용함과 동시에 주의의 대상에 따라 방향성도 차별적인 것으로 나타났다. 이와 같은 연구결과는 인터넷 광고전략에 유용한 시사점을 제공하리라 기대된다. The previous articles for the perceived clutter in banner advertising has been dealt with what factors effect advertising clutter and relationship between advertising clutter and advertising attitude. But internet is possible media with a two-way communication. So, consumer have the right for control with selective avoidance or selective watching to advertising in internet. Therefore, this article intends to research internet advertising as experience process in the perspective of two-way communication replicated continuously. At first, researchers hypotheses about the effect of flow on perceived clutter and advertising attitude directly in banner advertising. Second, we are especially developed conceptual model considering perceived behavior control, intervening variable, in the relationships between flow, perceived clutter and advertising attitude by a subject of attention in banner advertising. The reason of established second hypothesis is to account for that experience process is accompany with user's emotional feelings by a subject of attention. The results of analysis, hypothesis for the role of flow and perceived behavior control including the possibility for decreasing perceived clutter is verified. And perceived behavior control verified as intervening variable in the relationship between flow and advertising attitude by a subject of attention. The results of study provide the strategic implication in internet advertising strategy.

바닥재 처리로 인한 수송 트레일러의 수직진동 감쇠 효과

이홍주,홍종호,김성엽 안성산업대학교 2002 論文集 Vol.34 No.-

This study was aimed to prevent the quality loss of agricultural products, which could be occurred by the vibrations of transporting trailer. The vibration absorption effect was measured and analyzed by mounting the polystyrene material on the bottom of trailer. The transporting trailer was tested with being mounted by the pear boxes up to fourth floor. The results of this study could be summarized as follows: 1. At low engine speed of 500rpm, the average vertical vibration level of the first floor boxes (lowest boxes) was reduced to almost half of the non-mounting system. And, at the fourth floor boxes (highest boxes), the vibration absorption effect was higher as about 10 times compared with the non-mounting system. 2. At standard engine speed of 1,000rpm, the average vertical vibration level of the first floor boxes was almost same as 0.005㎨ and 0.006㎨ respectively, but at the fourth floor boxes, the average vertical vibration was reduced to almost 60% of the non-mounting system.

바닥재 처리로 인한 수송 트레일러의 3차원진동 감쇠 효과

홍종호,이성범,김성엽 안성산업대학교 2002 論文集 Vol.34 No.-

This study was aimed to prevent the quality loss of agricultural products, which could be occurred by the vibrations of transporting trailer. The vibration absorption effect was measured and analyzed by mounting the polystyrene material on the bottom of trailer. The transporting trailer was tested with being mounted by the pear boxes up to fourth floor. The results of this study could be summarized as follows: 1. At low engine speed of 500rpm, average 3-dimensional accelerations of the polystyrene mounting system were showed similar results by the 3-directions as 0.0005 ~ 0.0006㎨, but those were reduced to 1/2 ~ 1/20 level of the non-mounting system. 2. At standard engine speed of 1,000rpm, the average 3-dimensional accelerations of the polystyrene mounting system were showed similar results by the 3-directions as 0.0005 ~ 0.0006㎨, and also showed similar results as 0.0006 ~ 0.0008㎨ for the non-mounting system. 3. For the accumulated vibration levels, the more low-frequency accelerations were occurred at the non-mounting system, which would make severe effect on the transporting loss.

진동감쇠 장치를 부착한 트레일러의 3축진동

홍종호,이성범,김성엽 한경대학교 2003 論文集 Vol.35 No.-

This study was aimed to find out the basic information for reducing damage of agricultural products during transportation. The vibration absorption system, consisted of suspension at wheel mounting and coil spring & rubber at hitch part, was developed and tested for the vibration characteristics. The 3-dimensional acceleration levels were measured at engine and trailer part according to the low(500rpm), medium(1000rpm), and high(1200rpm) engine speed. The results of this research could be summarized as follows; (1) For low engine speed of 500rpm, the average accelerations of engine part were 0.0085 m/s², 0.0238m/s². and 0.0182 m/s² for X-, Y-, Z-direction, respectively. Those of trailer part were 0.0162 m/s², 0.013 m/s². and 0.0l06 m/s² for X-, Y-, Z-direction respectively. And the peak accelerations of trailer part were 0.19 m/s², 0.34 m/s², and 0.18 m/s² for X-, Y-, Z-direction, respectively at 80Hz of frequency. (2) For medium engine speed of 1,000rpm, the average accelerations of trailer part were 0.0164 m/s², 0.011 m/s². and 0.0104 m/s² for X-, Y-, Z-direction, respectively. And the peak accelerations were 0.31 m/s² at 100Hz, 0.29 m/s² at 70Hz, and 0.28 m/s² at 100Hz for X-, Y-, Z-direction, respectively. (3) For high engine speed of 1,200rpm, the average accelerations of trailer part were 0.0293 m/s², 0.0194 m/s². and 0.022 m/s² for X-, Y-, Z-direction, respectively. And the peak accelerations were 1.2 m/s², 1.1 m/s², and 1.9 m/s² for X-, Y-, Z-direction, respectively at 60Hz of frequency. (4) For the driving of power tiller at speed of 0.35m/s on the controlled road, the average accelerations of trailer part were 0.018 m/s², 0.031 m/s². and 0.027 m/s² for X-, Y-, Z-direction, respectively. And the peak accelerations were 0.13 m/s², 0.24 m/s², and 0.29 m/s² for X-, Y-, Z-direction, respectively.

알코올 사용 장애 환자에서 알코올 사용의 심각도에 따른 불안 및 우울 증상과의 연관성

천은진,이준엽,구본훈,문보영,정진영,정성훈 대한생물치료정신의학회 2011 생물치료정신의학 Vol.17 No.2

Objectives:The purpose of this study was to examine the relationships of anxiety& depressive symptoms according to the severity of alcohol use in patients with alcohol use disorder. Methods:A total of 85 patients with alcohol use disorders were enrolled in this study. The severity of alcohol use was measured by the Korean version of alcohol use disorders identification test(AUDIT-K)& National Alcohol Screening test(NAST). Anxiety and depressive symptoms were measured by using the Beck Anxiety Inventory(BAI) and the Beck Depression Inventory(BDI), respectively. Pearson’s correlation test was applied to correlate among the severity of alcohol use, anxiety and depressive symptoms. Results:The mean scores of AUDIT-K, NAST, BAI and BDI were 22.22(±8.28), 6.24(±3.25), 18.64(±13.08), and 22.05(±10.13), respectively. Pearson’s correlation test showed that between the score of AUDIT-K and NAST, BAI or BDI, there were positively significant correlations(r=.534, p<.01 r=.231, p<.05 r=.334, p<.01), respectively. And in cases of≥26 score of AUDIT-K, there were much more positive correlations with BAI(r=.425, p<.05). Conclusion:The results of this study demonstrated that patients with alcohol use disorders have high co-morbid anxiety and depressive disorders. Overall, the greater severity of alcohol use may be associated with more anxiety and depressive symptoms. However, it is suggested that in the patients with severe alcohol use, correlation appeared to be positive only for anxiety symptoms.

Insulated Gate Transistor의 설계 및 제작

정상구,김진형,최연익,이동엽,황성규,성만영 亞洲大學校 1988 論文集 Vol.11 No.-

In this paper, we discuss fabrication and characteristics of the singular and the array-type insulated gate transisters(IGT). The starting wafers were two kinds: for a singular type IGT, p type(100) silicon with n??buffer and n??epitaxial layer; for a array-type IGT, p type(111) silicon with the n??epi layer. The channel regions were defined using the self-aligned double-diffusion process. Aluminum and poly silicon gate were used in the singular and array-type IGT, respectively. Characteristics of the singular IGT shows threshold voltage of 4 V, breakdown voltage of 73V and forward voltage drop of 0.7V. On the whole, the experimental results were in agreement with the theoretical ones when comparing the breakdown voltage and forward voltage drop. On the other hand, array-type IGT shows poor I-V characteristics, relatively low breakdown voltage and large leakage current.