• Title/Summary/Keyword: 동요

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Fast Detection of Video Copy Using Spatio-Temporal Group Feature (시공간 그룹특징을 사용한 동영상 복사물의 고속 검색)

  • Jeong, Jae Hyup;Lee, Jun Woo;Kang, Jong Wook;Jeong, Dong Seok
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.11
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    • pp.64-73
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    • 2012
  • In this paper, we propose a method to search for identical videos. The proposed method is spatio-temporal group feature fingerprinting. Frame of video is extracted from fixed rate method and is partitioned into vertical group and horizontal group. Descriptor is made of each group feature that is extracted from binary fingerprinting. Next, use descriptor of original video to build a two type of fingerprinting database and matching with query video. To efficient and effective video copy detection, method have high robustness, independence, matching speed. In proposed method, group feature have high robustness and independence in variable modification of video. Building a original fingerprinting database is able to fast matching with query video. The proposed method shows performance improvement in variable modifications in comparison to the existing methods. Especially, very singular performance in speed improvement is great advantage of this paper.

Numerical Analysis for Nonlinear Static and Dynamic Responses of Floating Crane with Elastic Boom (붐(Boom)의 탄성을 고려한 해상크레인의 비선형 정적/동적 거동을 위한 수치 해석)

  • Cha, Ju-Hwan;Park, Kwang-Phil;Lee, Kyu-Yeul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.4
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    • pp.501-509
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    • 2010
  • A floating crane is a crane-mounted ship and is used to assemble or to transport heavy blocks in shipyards. In this paper, the static and dynamic response of a floating crane and a heavy block that are connected using elastic booms and wire ropes are described. The static and dynamic equations of surge, pitch, and heave for the system are derived on the basis of flexible multibody system dynamics. The equations of motion are fully coupled and highly nonlinear since they involve nonlinear mass matrices, elastic stiffness matrices, quadratic velocity vectors, and generalized external forces. A floating frame of reference and nodal coordinates are employed to model the boom as a flexible body. The nonlinear hydrostatic force, linear hydrodynamic force, wire-rope force, and mooring force are considered as the external forces. For numerical analysis, the Hilber-Hughes-Taylor method for implicit integration is used. The dynamic responses of the cargo are analyzed with respect to the results obtained by static and numerical analyses.

주석 전기도금과 열압착본딩을 이용한 Bi2Te3계 열전모듈의 제작

  • Yun, Jong-Chan;Choe, Jun-Yeong;Son, In-Jun;Jo, Sang-Heum;Park, Gwan-Ho
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2017.05a
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    • pp.129-129
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    • 2017
  • 열전재료는 열에너지를 전기에너지로 또는 전기에너지를 열에너지로 직접 변환하는데 가장 널리 사용되는 재료이다. $Bi_2Te_3$계 열전 재료는 400K 이하의 비교적 저온 영역에서 높은 성능지수(Dimensionless Figure of merit, ZT($={\alpha}2{\sigma}T/{\kappa}$, ${\alpha}$: 제백계수, ${\sigma}$: 전기전도도, T: 절대온도, ${\kappa}$: 열전도도))를 나타내는 열전재료이며 자동차 시트나 정수기 등에 응용되고 있다. 열전모듈은 제조시 수십 개에서 수백 개 이상의 n형 및 p형 열전소자를 알루미나($Al_2O_3$)와 같은 세라믹 기판(substrate) 상에 접합된 동 전극 위에 전기적으로 서로 직렬로 접합시켜 제조한다. 기존의 열전모듈의 제조방법에는 동 전극 위에 위에 Sn합금 분말과 플럭스(flux)의 혼합물인 솔더페이스트를 스크린 인쇄법을 사용하여 동 전극에 도포한 다음, 그 위에 열전소자를 얹고 약 520K의 열풍을 가하여 솔더를 용융시켜 열전소자와 동 전극을 접합시킨다. 스크린 인쇄법에서는 인쇄 압력이 일정하지 않으면, 솔더페이스트 층의 두께가 균일하지 않게 되어 열전소자 접합부의 불량을 유발시킨다. 그러나 열모듈은 단 하나의 접합 불량이 모듈 전체의 열전변환성능에 심각한 영향을 줄 수 있기 때문에 본 연구에서는 이러한 문제점을 해결하기 위해, 솔더페이스트를 도포하지 않고 열전소자를 직접 동 전극과 접합할 수 있는 방법을 고안하였다. 무전해도금을 이용한 니켈층을 형성시킨 $Bi_2Te_3$계 열전소자 표면에 약 $50{\mu}m$의 주석도금층을 전기도금법을 구사하여 형성시켰다. 그 후, wire cutting을 통하여 $3mm{\times}3mm{\times}3mm$의 크기로 절단한 주석도금된 열전소자를 동 전극에 얹고 1.1KPa의 압력을 가하면서 523K의 핫플레이트 위에서 3분간 방치하여 직접(direct) 열압착 접합을 실시하였다. 접합부의 단면을 SEM을 이용하여 관찰한 결과, 동 전극과 열전소자 사이의 계면에 용융 후 응고된 주석층이 결함없이 균일하게 형성된 양호한 접합부를 관찰할 수 있었다. 따라서, 솔더페이스트를 이용하지 않고, 열전소자 표면에 주석도금을 실시한 후, 동 전극과 직접 열압착 본딩을 실시하는 방법은 균일한 접합계면을 얻을 수 있는 새로운 공정으로 기대된다.

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Comparison of Educational Effects between Song·Video Self Study of Cardiopulmonary Resuscitation(CPR) and Video Self Instruction(VSI) of CPR by Middle School Students (일부 중학생의 심폐소생술에 관한 노래·동영상 자가 학습과 심폐소생술 동영상 자가 학습(VSI)과의 교육 효과 비교)

  • Park, Dae-Sung
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.225-235
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    • 2010
  • This study examined the educational effects by song video self study of CPR and CPR VSI with middle school students who have no CPR education experience and aimed to provide basic materials for effective CPR education method with middle school students. The subjects of the research were total 68 middle school students of S middle school in G metropolitan city and they were selected by convenience sampling into 33 experimental group and 35 control group. The period of examination was from Apr. 22 to 23, 2009 and the data were collected for two days. As a result of the research, song video self learning of CPR with middle school students was not considered as achieving better results than video self learning. But, as its educational effects were confirmed, it will be available in education of CPR with middle school students.

A Study on Revision of Regulations to Promote Recycling of Animal and Plant Residues (동·식물성잔재물의 재활용 촉진을 위한 관련 법규 개정 연구)

  • Oh, Gil-Jong;Park, Seon-Oh;Kim, Ki-Heon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.25 no.2
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    • pp.77-90
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    • 2017
  • In order to promote recycling of animal and plant residues, it is necessary to prepare detailed statistics on the sources, generation amount and the state of disposal so that waste recycling companies and enterprises can obtain the information easily. Also, the recycling methods specified in the law should be appropriate. For this, the study reviewed the appropriateness of detailed classification of animal and plant residues and permitted recycling methods in the Enforcement Regulations of the Waste Management Act of Korea. For improvement of the detailed classification, the study conducted literature review on European and Japanese ones. Additionally, we visited slaughterhouses of livestock and poultry, vegetable oils manufacturing companies, starches and glucose or maltose manufacturing companies, which generate the waste and recycle the waste, to grasp the status of recycling in Korea. Based on the results, the study proposes improvement measures for the detailed classification and the permitted recycling types in the law.

Measurement of postural instability before and after experiencing a VR system by using a force platform (힘판을 이용한 가상현실 체험 전후 신체동요의 측정)

  • 박재희;김영윤;김은남;김현택;고희동
    • Science of Emotion and Sensibility
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    • v.5 no.4
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    • pp.45-49
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    • 2002
  • Recently, virtual environment systems are used in various application fields such as industry, medicine, and training and education. However, the negative effect, cybersickness including nausea, visual fatigue, and disorientation, could be happened while using VR systems. It prevents VR system from spreading much more. To control the cybersickness, first of all, the objective measurement method should be established. As one of alternative methods, the postural instability could be a measure of cybersickness. In this study, 45 participants' postural sway before and after experiencing a H driving simulator was measured by using a force platform. Especially, we examined if two factors, motion and feedback, could affect on the postural instability The results showed the postural instability slightly increased after experiencing the VR driving simulator. For the factors, the providing of motion synchronized to visual display showed statistical significant decrease in postural sway along lateral side. To check the effectiveness of postural instability as a cybersickness measure, further studies are needed.

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Fast Generation of 3-D Video Holograms using a Look-up Table and Temporal Redundancy of 3-D Video Image (룩업테이블과 3차원 동영상의 시간적 중복성을 이용한 3차원 비디오 홀로그램의 고속 생성)

  • Kim, Seung-Cheol;Kim, Eun-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.10B
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    • pp.1076-1085
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    • 2009
  • In this paper, a new method for efficient computation of CGH patterns for 3-D video images is proposed by combined use of temporal redundancy and look-up table techniques. In the conventional N-LT method, fringe patterns for other object points on that image plane can be obtained by simply shifting these pre-calculated PFP (Principle Fringe Patterns). But there have been many practical limitations in real-time generation of 3-D video holograms because the computation time required for the generation of 3-D video holograms must be massively increased compared to that of the static holograms. On the other hand, as ordinary 3-D moving pictures have numerous similarities between video frames, called by temporal redundancy, and this redundancy is used to compress the video image. Therefore, in this paper, we proposed the efficient hologram generation method using the temporal redundancy of 3-D video image and N-LT method. To confirm the feasibility of the proposed method, some experiments with test 3-D videos are carried out, and the results are comparatively discussed with the conventional methods in terms of the number of object points and computation time.

Strength and sulfuric acid resistance properties of cement mortar containing copper slag (동 제련 슬래그를 사용한 시멘트 모르타르의 강도 및 황산저항 특성)

  • Hong, Chang Woo;Lee, Jung-Il;Ryu, Jeong Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.26 no.3
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    • pp.101-108
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    • 2016
  • Each year, more than seven hundred thousand tons of copper slag are generated in Korea as a byproduct during the production of copper. Due to the large amount of copper slag produced, there has been increased interest in the use of copper slag as a construction material. To evaluate the potential of copper slag as a construction material, laboratory evaluations were conducted in this study, and three particle shapes and replacement rates of river sand were selected as experimental variables. Strength, air-void characteristics, and sulfuric acid resistance were the three properties evaluated to assess whether copper slag can be used as a construction material. Test results indicate that the gradation of copper slag has an effect on strength, and the maximum strength was achieved when 60 % of river sand was replaced with copper slag. In addition, when compared with ordinary Portland cement mortar, replacing river sand with copper slag reduced air void size and increased sulfuric acid resistance.

Bread Quality with Boiled Wax Gourd (Benincasa hispida) (열처리 동아(Benincasa hispida)를 첨가한 빵의 품질 특성)

  • Ju, In-Ok;Jung, Gi-Tai;Ryu, Jeong;Choi, Joung-Sik;Choi, Yeong-Geun;Kim, Young-Soo
    • Korean Journal of Food Science and Technology
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    • v.35 no.2
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    • pp.195-200
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    • 2003
  • Effects of mashed wax gourd (Benincasa hispida) on texture and sensory quality of bread were evaluated. Farinograph results revealed increase in mechanical tolerance index (MTI) and water absorption, and decrease in dough stability with the addition of wax gourd. Addition of wax gourd also decreased loaf weight and volume. L, a, and b values of crust decreased with increasing addition of wax gourd, Whereas no effect on the color of crumb, Firmness of bread crumb increased with the addition of wax gourd at 67%, resulting in significant increase in hardness, gumminess, and chewiness of bread. Sensory evaluation revealed that acceptable quality of bread could be obtained by the addition of wax gourd up to 50%.

Mdlti-View Video Generation from 2 Dimensional Video (2차원 동영상으로부터 다시점 동영상 생성 기법)

  • Baek, Yun-Ki;Choi, Mi-Nam;Park, Se-Whan;Yoo, Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.1C
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    • pp.53-61
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    • 2008
  • In this paper, we propose an algorithm for generation of multi-view video from conventional 2 dimensional video. Color and motion information of an object are used for segmentation and from the segmented objects, multi-view video is generated. Especially, color information is used to extract the boundary of an object that is barely extracted by using motion information. To classify the homogeneous regions with color, luminance and chrominance components are used. A pixel-based motion estimation with a measurement window is also performed to obtain motion information. Then, we combine the results from motion estimation and color segmentation and consequently we obtain a depth information by assigning motion intensity value to each segmented region. Finally, we generate multi-view video by applying rotation transformation method to 2 dimensional input images and the obtained depth information in each object. The experimental results show that the proposed algorithm outperforms comparing with conventional conversion methods.