• Title/Summary/Keyword: Moire

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Thermo-mechanical Behavior of WB-PBGA Packages with Pb-Sn Solder and Lead-free Solder Using Moire Interferometry (무아레 간섭계를 이용한 유연 솔더와 무연 솔더 실장 WB-PBGA 패키지의 열-기계적 변형 거동)

  • Lee, Bong-Hee;Kim, Man-Ki;Joo, Jin-Won
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.3
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    • pp.17-26
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    • 2010
  • Pb-Sn solder is rapidly being replaced by lead-free solder for board-level interconnection in microelectronic package assemblies due to the environmental protection requirement. There is a general lack of mechanical reliability information available on the lead-free solder. In this study, thermo-mechanical behaviors of wire-bond plastic ball grid array (WB-PBGA) package assemblies are characterized by high-sensitivity moire interferometry. Experiments are conducted for two types of WB-PBGA packages that have Pb-Sn solder and lead-free solder as joint interconnections. Using real-time moire setup, fringe patterns are recorded and analyzed for several temperatures. Bending deformations of the assemblies and average strains of the solder balls are investigated and compared for the two type of WB-PBGA package assemblies. Results show that shear strain in #3 solder ball located near the chip shadow boundary is dominant for the failure of the package with Pb-Sn solder, while normal strain in #7 most outer solder ball is dominant for that with lead-free solder. It is also shown that the package with lead-free solder has much larger bending deformation and 10% larger maximum effective strain than the package with Pb-Sn solder at same temperature level.

Diagnosis of Work-related Musculoskeletal Disease through Moire Image Pattern and Treatment Measure using a Sling System (Moire' 영상무늬를 통한 근골격계질환의 진단과 현가장치를 이용한 치료방안)

  • Lee Sang-Yong;Lee Eun-Kyong;Kwon So-Hee;Jung He-Kyong;Kim Sam-Tae;Chong Myong-Soo;Lee Ki-Nam
    • Journal of Society of Preventive Korean Medicine
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    • v.7 no.2
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    • pp.121-130
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    • 2003
  • The Musculoskeletal Disease has been ignored or turned away due to the difficulty of diagnosis and the vagueness of judgement up to now. Contrary to other diseases, there were many cases where the character of the Musculoskeletal Disease wasn't revealed through the objective inspection. And that's because the Musculoskeletal Disease appears for the most part due to muscular defect so it is impossible to diagnose the muscle by X-ray diagnosing the bone and it is also impossible to diagnose the fine damage of the muscle or tendon even by advanced device like MRI. As the nervous blood vessels or acupunctures pass through or are next to the muscle, the tension of the muscle put pressure on these so can become the direct or indirect causes of various kinds of pains or intern diseases. But in spite of that, for lack of proper equipment diagnosing the state of the muscle(Shortened.. Relaxed... or Hardened...) the muscle has been disregarded or neglected intentionally or unintentionally. While many people think themselves to be a muscular expert, if they don't see the shape of the muscle, that is just like blind treatment. But as now the equipment diagnosing the state of the muscle is developed, it seems that this problem can be settled. It was attempted in this study that the muscle or skeleton of the Musculoskeletal disease patients was diagno the treatment order and method were decided by a questionnaire survey and simple inspection, and the Musculoskeletal correction exercise using the muscle management and sling system made them escape from the Musculoskeletal disease, turning their muscle into more flexible and stronger muscle. As a result notwithstanding the limited treatment period '12 times', the improvement rate was as high as 74%, which showed that the muscle management and Musculoskeletal correction exercise had a great effect on the symptom improvement of the patients. If the treatment times had increased, the improvement rate also would have increased more.

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A Study on the Adequate HD Camera Focal Length in the Broadcasting Studio using LED Video Wall (LED 비디오월을 사용하는 방송환경에서 HD 카메라의 적정 초점거리 연구)

  • Choi, Ki-chang;Kwon, Soon-chul;Lee, Seung-hyun
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.5
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    • pp.713-721
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    • 2022
  • In order to use the LED video wall in the broadcasting studio, there are a few things to be aware of. First, since the pixels are closely arranged, a moire phenomenon may occur due to a short arrangement period, and second, the distance between pixels (pixel pitch) may be recorded on the image sensor of the broadcasting camera. When moire occurs or pixel pitch is observed, viewers feel uncomfortable. Moire effect can be reduced by adjusting the shooting distance or angle of the camera, but in order to prevent the pixel pitch from being recorded on the image sensor, secure a sufficient distance between the LED video wall and camera. even when the distance secured, the zoom lens used in the broadcasting studio must be operated by appropriately changing the magnification. If the focal length is changed by changing the magnification to obtain a desired angle of view, the pixel pitch may be unintentionally recorded. In this study we propose the range that the pixel pitch is not observed while changing the magnification ratio of the zoom lens when the distance from the video wall is sufficiently secured. The content was played back on the LED video wall and the LED video wall was recorded on the server using an HD camera equipped with a B4 mount zoom lens

A Study on Oriental Medical Diagnosis of Musculoskeletal Disorders using Moire Image (Moire 영상을 이용한 근골격계 질환의 한의학적 진단에 관한 연구)

  • Lee Eun-Kyoung;Yu Seung-Hyun;Lee Su-Kyung;Kang Sung-Ho;Han Jong-Min;Chong Myong-Soo;Chun Eun-Joo;Song Yung-Sun;Lee Ki-Nam
    • Journal of Society of Preventive Korean Medicine
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    • v.4 no.2
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    • pp.72-92
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    • 2000
  • This research has conducted studies on an Oriental medicine-based method of diagnosing of occupational musculoskeletal system diseases. This researcher has searched through existing relevant medical literature. Also, this researcher has worked on a moire topography using moire topography. In this course, this researcher has reached the following conclusion in relation to the possibility of using a moire topography as a diagnosing device of musculoskeletal system diseases under Oriental medicine . 1 The Western medicine outlines its criteria of screening occupational musculoskeletal system diseases as follows A. The occupational musculoskeletal diseases must clearly include one or more of the subjective symptoms characterized by pain, hypoesthesia dysaesthesia, anaesthesia. etc . B, There should be clinically admitted objective observations and diagnosis outlining that the disease concerned shows symptoms such as tenderness, induration. and edema that can appear with occupational musculoskeletal system diseases. dyscinesia should be admitted with the disease concerned, or there should be observations and diagnosis outlining that abnormality exists in electric muscular or nervous diagnosis and examination . C. It should be admitted that prior to the occurrence of symptoms or observations and diagnosis on musculoskeletal system-related diseases, a patient has been engaged in works with conditions requiring improper work posture or work movement. That is, this is an approach whereby they see abnormality in the musculoskeletal system come from material and structural defect, and adjust and control abnormality in the musculoskeletal system and secreta . 2. The Oriental medicines sees that a patient develops the pain of occupational musculoskeletal diseases as he cannot properly activate the flow of his life force and blood thus not only causing formation of lumps in the body and blocking the flow of life force and blood in some parts of the body. Hence, The Oriental medicine focuses on resolving the cause of weakening the flow of life force and blood, instead of taking material approach of correcting structural abnormality Furthermore , Oriental medicine sees that when muscle tension builds up, this presses blood vessels and nerves passing by, triggering circulation dyscrasia and neurological reaction and thus leading to lesion. Thus, instead of taking skeletal or neurophysiological approach. it seeks to fundamentally resolve the cause of the flow of the life force and blood in muscles not being activated. As a result Oriental medicine attributes the main cause of musculoskeletal system diseases to muscle tension and its build-up that stem from an individual's long formed chronicle habit and work environment. This approach considers not only the social structure aspect including companies owners and work environment that the existing methods have looked at, but also individual workers' responsibility and their environmental factors. Hence, this is a step forward method. 3 The diagnosis of musculoskeletal diseases under Oriental medicine is characterized by the fact that an Oriental medicine doctor uses not only photos taken by himself, but also various detection devices to gather information and pass comprehensive judgment on it. Thus, it is the core of diagnosis under Oriental medicine to develop diagnosing devices matching the characteristics of information to be induced and to interpret information so induced from the views of Oriental medicine. Diagnosis using diagnosing devices values the whole state of a patient and formal abnormality alike, and the whole balance and muscular state of a patient serves as the basis of diagnosis. Hence, this method, instead of depending on the information gathered from devices under Western medicine, requires devices that provide information on the whole state of a patient in addition to the local abnormality information that X-ray. CT, etc., can offer. This method sees muscle as the central part of the abnormality in the musculoskeletal system and thus requires diagnosing devices enabling the muscular state. 4. The diagnosing device using moire topography under Oriental medicine has advantages below and can be used for diagnosing musculoskeletal system diseases with industrial workers . First, the device can Provide information on the body in an unbalanced state. and thus identify the imbalance and difference of height in the left and right stature that a patient can not notice at normal times. Second, the device shows the twisting of muscles or induration regions in a contour map. This is not possible with existing shooting machines such as X-ray, CT, etc., thus differentiating itself from existing machines. Third, this device makes it possible for Oriental medicine to take its unique approach to the abnormality in the musculoskeletal system. Oriental medicine sees the state and imbalance state in muscles as major factors in determining the lesion of musculoskeletal system, and the device makes it possible to shoot the state of muscles in detail. In this respect, the device is significant. Fourth, the device has an advantage as non-aggression diagnosing device.

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Moire' Free Pseudo-Random Method in Digital Halftoning (무아레 억제용 의사 랜덤 망점화)

  • 박희윤
    • Journal of the Korean Graphic Arts Communication Society
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    • v.15 no.2
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    • pp.91-106
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    • 1997
  • The new algorithm for halftone generation for gravure engraving was developed. The basic concept of this algorithm is based on the mapping and equal density expansion methods that we are mapped out. The program was used by the Microsoft Visiul C++2.0 and could be loaded in IBM personal computer.

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