• 대한수학회보
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• 제52권1호
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• pp.215-222
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• 2015

We show that homology group on a contact CR-warped product submanifold in odd dimensional sphere is zero under certain conditions in terms of warping function and the dimension of the submanifold.

• 대한수학회보
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• 제33권4호
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• pp.521-530
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• 1996

This paper treats the existence of odd solutions of the Cauchy problem for a perturbation of a conservation law.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제5권1호
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• pp.79-86
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• 1998

In this paper, we study an (n ＋ 1)-dimensional compact, orientable, minimal contact CR-submanifold of (n - 1) ontact CR-dimension in a (2m ＋ 1)-dimensional unit sphere $S^{2m＋1}$ in terms of integral formula.

• 한국정보과학회논문지:시스템및이론
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• 제35권7호
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• pp.318-326
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• 2008

본 논문에서는 하이퍼큐브보다 망비용이 개선된 폴디드 하이퍼큐브 연결망과 이븐연결망, 오드 연결망 사이의 임베딩을 분석한다. 연구 결과로 폴디드 하이퍼큐브 $FQ_n$을 이븐연결망 $E_{n-1}$에 연장율 2, 밀집율 1에 임베딩 가능함을 보이고, 이븐연결망 $E_d$을 폴디드 하이퍼큐브 $FQ_{2d-3}$에 연장율 1에 임베딩 가능함을 보인다. 또한, 폴디드 하이퍼큐브 $FQ_n$는 오드연결망 $O_{n-1}$에 연장율 2, 밀집율 1에 임베딩 가능함을 보이고, 오드연결망 $O_d$는 폴디드 하이퍼큐브 $FQ_{2d-1}$에 연장율 2, 밀집율 1에 임베딩 가능함을 보인다. 마지막으로, 이븐연결망 $E_d$는 오드연결망 $O_d$에 연장을 2, 밀집을 1에 임베딩 가능함을 보이고, 오드연결망 $O_d$는 이븐연결망 $E_{d-1}$에 연장율 2, 밀집율 1에 임베딩 가능함을 보인다.

• 대한기계학회논문집B
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• 제27권1호
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• pp.25-31
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• 2003

Airborne contaminant particles are intruded into optical disk drives(ODD) due to the flow caused by disk rotation and can be adhered to lens or disk surfaces, which causes decrease of laser power and increase of read/write errors. Such a phenomenon can be more serious as the space between the disk and the lens is reduced fur high-density storage devices. The purpose of this paper is to understand design parameters to reduce the particle intrusion into an ODD. Suggestions are made to prevent the particle intrusion that can decrease the stability of an ODD and also prevent the potential heat build-up problem. The sealing effect of drive and the forced injection of clean air (using HEPA filter) into the drive minimizes intrusion of the outside air and dusts in an ODD remarkably. Moreover it is proved by experiments that the installation of a heatproof pad to isolate heat generation part (PCB) from information read/write sections and the forced injection of dust-free air reduce the gas temperature inside the drive as well as the amount of particles intruded.

• 제어로봇시스템학회논문지
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• 제8권7호
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• pp.539-546
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• 2002

This paper presents a new direct seek control scheme that provides fast data access capability and robust performance for high-speed rotational optical disk drives (ODD). When a disk is rotating at a high speed to obtain fast data transfer in ODD, the magnitude and frequency of velocity disturbance caused by eccentric rotation of the disk increase in proportion to the rotational speed of the disk. Such disturbances make it almost impossible for the conventional seek control scheme to achieve stable and satisfactory seek performance. We analyze the problems that may arise when the conventional seek control scheme is applied to the high-speed rotational ODD and propose a new direct seek control scheme that will solve such problems. In the proposed scheme, a seek control system is designed such that its performance is guaranteed for a set of plants with parameter perturbations. The performance of the proposed seek control scheme is shown by experiments using a high-speed rotational ODD.

• 한국정보과학회논문지:시스템및이론
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• 제36권5호
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• pp.429-436
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• 2009

오드 연결망은 그래프이론 모델의 하나로 발표되었는데, [1]에서 고장허용 다중컴퓨터에 대한 하나의 모형으로 소개되었고, 여러 가지 유용한 성질들 - 간단한 라우팅 알고리즘, 최대고장허용도, 노드 중복 없는 경로 등 - 이 분석되었다 본 논문에서는 오드 연결망 $O_d$ 에서 에지 중복 없는 스패닝 트리를 구성하는 알고리즘을 제안한다. 그리고 제안한 알고리즘에 의해 구성된 에지 중복 없는 스패닝 트리가 에지 중복 없는 최적 스패닝 트리임을 증명한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.672-675
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• 2006

It is becoming more significant to develop a rotary VCM type actuator for small form factor ODD, as portables are getting more and more popularized nowadays. In this paper, the procedure of development of the actuator which is applicable to compact flash II card and is fit in the specification of BD 1X is explained. This is based on the rotary VCM type actuator, which is good for reducing thickness. Air core solenoid coil is used in order to do focusing mechanism. And the total weight is reduced by using the structure of steel-aluminium-steel triple layer, so, the stiffness is still adequate. Additionally, the tracking coil is moved next to the actuator, so the total length was reduced, then the actuator become applicable to compact flash II card. The force of Magnetic Circuit is improved by using Magnetic Circuit DOE. And flexible mode frequency improved through the DOE of structure part. Modeling was exactly done in consideration of air core solenoid coil and pivot bearing. It is confirmed that the designed model is satisfied with the specification of BD 1X and is applicable to Compact Flash II card.

• Macromolecular Research
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• 제10권4호
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• pp.230-235
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• 2002

Alternating polyols of oxymethylene and oxyalkylene were synthesized and used as precursors for thermoplastic poly(ether-ester) elastomers (TPEs). The polyols were synthesized by reacting diols having different methylene units with dichloromethane in the presence of a phase transfer catalyst. The number of methylene units in the alkylene oxides was varied from 3 to 6. TPEs were prepared using the polyols as soft segments and poly(butylene terephthalate) units as hard segments. The polyols and TPEs synthesized were characterized using FTIR, NMR, GPC, DSC, and polarized optical microscopy. The polyols showed a profound odd-even effect on the melting (T$_{m}$) and glass transition temperatures (T$_{g}$). Polyols with odd numbers of methylene groups in the alkylene units have higher transition temperatures than polyols with odd number of methylene groups. The tendency is still kept in TPEs, even though the T$_{g}$ of soft segment in TPEs are slightly higher than those of corresponding neat polyols. The T$_{m}$ and T$_{g}$ of soft segments are almost constant in the range of 20 to 60 wt % contents of soft segments. On the other hand, the normalized heat of fusion of hard segment decreased with increasing the content of loft segment.ent.t.ent.

• 대한전자공학회논문지SD
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• 제37권10호
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• pp.57-64
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• 2000

본 논문에서는 동적 프로그래밍에 기반한 스테레오 정합 알고리듬을 구현하는 새로운 하드웨어 구조를 제안하였다. 제안된 MOEPE(Merged Odd-Even PE) 구조는 시스톨릭 방법으로 동작하고, 극상선상의 화소의 밝기 값으로부터 변이를 찾는다. MOEPE구조에서 사용된 PE 수는 변이제약조건의 수와 일치하는데, 이는 극상선상의 화소 수만큼의 PE를 사용하는 기존의 방법에 비하여 훨씬 적은 수의 PE를 사용한다. MOEPE 구조에서 사용된 PE 수는 일반적 크기의 영상에 대하여, 기존의 방법에 비하여 약 25배 적은 수의 PE를 사용한다. 제안된 구조는 VHDL로 기술하였고, Synopsys 설계 환경에서 시뮬레이션을 수행하였다.