• Title/Summary/Keyword: 접촉 역학

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The Study of an Anisotropy for Fabric Surface Roughness by using a Non-Contact Measuring System (비접촉 표면 굴곡 측정방법을 이용한 직물 표면의 이방성 연구)

  • 박경희;권영하;권현준;오경화
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.407-409
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    • 2003
  • 직물의 질감을 객관화시키는 연구는 고부가가치의 의류제품을 생산하고 판매하는데 매우 중요한 요소이다. 섬유제품의 표면 거칠기에 대한 연구를 통해, 인간이 섬유제품에서 느끼는 촉감과 그러한 촉각을 느끼게 하는 여러 물리적, 기계적 요인들과의 관계를 조사하고, 인간이 제품을 만질 때 느끼는 감성을 객관화 하여 감성적인 제품의 생산에 응용할 수 있는 자료를 마련해 보고자 한다. 질감은 직물의 역학적 성질과 표면 상태에 따라 좌우되는데 직물은 경사와 위사가 서로 엮어지고 짜여져 표면굴곡과 이방성을 가지게 된다. (중략)

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Deformation pathway of semiconductor materials in nanometer scale (반도체 소재의 나노미터 스케일의 변형거동 해석)

  • Kim, Dong-Earn;Oh, Soo-Ik
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.518-520
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    • 2007
  • Since all essential property of semiconductor materials are structure-sensitive, the understanding of the deformation mechanism and the deformed structure which can be formed in the nanometer-scale devices is very crucial. To investigate the deformation mechanism and the corresponding structures, nanometer-scale contact loading simulations are carried out using molecular dynamics in silicon and gallium-arsenide.

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내열성 방염직물의 역학 특성과 수분전달 특성

  • 정유미;안승국
    • Proceedings of the Korean Fiber Society Conference
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    • 1998.10a
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    • pp.426-429
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    • 1998
  • 의복의 여러 가지 기능 중 하나는 인간을 열이나 추운 환경으로부터 보호하는 것이다. 이러한 의복 중 방염직물(flame-resistant fabrics)은 산업적으로 열과 접촉하거나 위험한 환경에서 작업하는 작업자들을 열로부터 보호하는 중요한 역할을 하고 있다. 내열성 방염직물로 만들어진 작업복이 요구되어 지는 작업환경은 제철소에서와 같이 연속적으로 위험성이 있는 곳과 비행기 사고나 건물화재와 같은 잠재 위험성이 있는 곳 등이다[1]. (중략)

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Focus - 2020년도 감염병 관리사업지침

  • 대한산업보건협회
    • 월간산업보건
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    • s.383
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    • pp.42-55
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    • 2020
  • 협회에서는 최근 발생한 코로나바이러스감염증19와 관련하여 2020년도 감염병 관리사업지침을 소개합니다. 본 지침은 「감염병의 예방 및 관리에 관한 법률」 에 따른 감염병 감시, 역학조사, 실험실 검사, 감염병 환자 및 접촉자 관리, 감염병 예방, 방역, 지자체 역량강화에 관한 정확한 정보를 제공하여 업무수행의 효율성을 높이고자 제작하였습니다. 해당 내용은 질병관리본부의 <2020년도 감염병 관리사업지침>을 발췌하였습니다. 사업장 특성과 사정에 따라 참고하시길 바랍니다.

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Big Data based Epidemic Investigation Support System using Mobile Network Data (이동통신 데이터를 활용한 빅데이터 기반 역학조사지원 시스템)

  • Lee, Min-woo;Kim, Ye-ji;Yi, Jae-jin;Moon, Kyu-hwan;Hwang, SeonBae;Jun, Yong-joo;Hahm, Yu-Kun
    • The Journal of Bigdata
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    • v.5 no.2
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    • pp.187-199
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    • 2020
  • The World Health Organization declared COVID-19 a pandemic on March 11. South Korea recorded 27,000 cases of the coronavirus illness, and more than 50 million coronavirus cases were confirmed all over the world. An epidemiological investigation becomes important once again due to the spread of COVID-19 infections. However, there were a number of confirmed coronavirus cases from Deagu and Gyeongbuk. Limitations of the epidemiological investigation methods were recognized. The Korea Disease Control and Prevention Agency developed the Epidemiological Investigation Support System(EISS) to utilize the smart city data hub technology and utilized the system in the epidemiological investigation. As a part of EISS, The proposed system is big-data bsed epidemiological investigation support system processing mobile network data. The established system is the epidemiological investigation support system based on big data to process mobile carriers' big data. Processing abnormal values of mobile carriers' data which was impossible with existing staff or creating hotspot regions where more than two people were in contact with an infected person were realized. As a result, our system processes outlier of mobile network data in 30 seconds, while processes hotspot around in 10 minutes. as a first time to adapt and support bigdata system into epidemiological investigation, our system proposes the practical utilizability of big-data system into epidemiological investigation.

정규모드 동역학을 활용한 비선형 진동

  • 박철희
    • Journal of KSNVE
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    • v.7 no.1
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    • pp.6-12
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    • 1997
  • 물리계에서 일어나는 동적 현상들은 선형해석 만으로 설명하기에는 불충분한 점이 많이 있다. 이는 기계구조물과 같은 실제 계의 진동이 기하학적 비선형성, 강성 의 비선형성 또는 경계조건의 비선형성 등의 영향으로 비선형적인 거동을 하기 때문 이다. 비선형 진동을 하는 기계 계는 우리 주변에서 쉽게 찾아 볼 수 있는데, 그 예로써 진자운동을 포함하여 동흡진기, 회전체계, 공작기계의 절삭운동, 건마찰 (dry friction) 관련 기계장치, 치차 및 기차의 바퀴와 레일 간의 접촉에서 볼수 있는 구분적 선형(piecewise linear) 진동계, 충격 진동계 등을 들 수 있다. 비선형 진동 연구는 limit cycle, 준주기운동(quasiperiodic motion), 점프현상(jump phenomena) 등의 인식에서 시작되어, 과거에는 설명이 안되어 회피되 왔던 랜덤(random) 형태의 비주기운동에 대한 연구로 까지 발전하고 있다. 비선형 진동을 다루는데 있어서 정규모드(normal mode)를 이용하는 방법이 있다. 일반적으로 선형계는 선형 정규모드 (linear normal mode)가 존재하는 것과 같이 비선형계에도 이와 유사한 정규모드가 존재한다는 사실이 연구 보고된 바 있다. 비선형계에 존재하는 정규모드는 계의 매개 변수(system parameters)에 따라 그 안정성이 바뀔 수 있으며, 만일 안정한 정규모드 가 어떤 매개변수에서 그 안정성이 바뀐다면 선형이론으로는 설명될 수 없는 새로운 운동이 일어나고 이러한 운동을 분기모드(bifurcation mode)라고 한다. 안정한 정규 모드 및 분기모드를 포함하여 비선형계를 다류는 것을 "정규모드 동역학(normal mode dynamics)"이라고 한다. 정규모드 동역학은 앞에서 언급된 비선형 현상들의 원인규명, 예측, 안정성해석 및 강제진동 해석을 가능하게 한다. 또한 최근에 활발히 연구되고 있는 혼돈운동(chaotic motion)의 해석도 가능하다. 이 글에서는 비선형 진동해석을 위한 정규모드 동역학에 대한 연구동향 및 기본 이론을 살펴 보았고, 그 적용 예를 통하여 실험결과와 비교 고찰 함으로써 정규모드 동역학의 적용성을 서술하여 보았다. 선형이론으로 이해하기 어려운 현상들에 대하여는 비선형의 관점에서 새롭게 접근하 려는 노력이 필요하며 비선형 이론에 대한 연구가 지속적으로 진행되어야 한다. 진행되어야 한다.

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Criminal Law Issues in Epidemiological Investigations Under the INFECTIOUS DISEASE CONTROL AND PREVENTION ACT (감염병의 예방 및 관리에 관한 법률상 역학조사와 관련된 형사법적 쟁점)

  • Jang, Junhyuk
    • The Korean Society of Law and Medicine
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    • v.23 no.3
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    • pp.3-44
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    • 2022
  • As a result of a close review focusing on the case of obstruction of epidemiological investigation by a religious group A in Daegu, which was a problem when the pandemic of Covid-19 infection began in Korea around February 2, 2020, when an epidemiological investigator requested a specific group to submit a list, While there have been cases where an act of not responding or submitting an edited omission list was sentenced to the effect that the act did not fall under an epidemiological investigation, in the case of non-submission of the visitor list for the B Center, even though a 'list of visitors' was requested. Regarding the fact of refusal without a justifiable reason, 'providing a list of persons entering the building is a key factual act that forms a link between epidemiological investigations accompanying an epidemiological investigation, and refusing to do so is also an act of refusal and obstruction of an epidemiological investigation. There are cases where it is possible to demand criminal punishment. Regardless of whether the request for submission of the membership list falls under the epidemiological investigation, there are cases in which the someones' actions correspond to the refusal or obstruction of the epidemiological investigation. A lower court ruling that if an epidemiological investigation is rejected or obstructed as a result of interfering with factual acts accompanying an epidemiological investigation, comprehensively considering whether or not the list has been diverted for purposes other than epidemiological investigation, the logic is persuasive. Epidemiological investigations such as surveys and human specimen collection and testing are conducted for each infectious disease patient or contact confirmed as a result of the epidemiological investigation, but epidemiological investigations conducted on individual individuals cannot exist independently of each other, and the This is because the process of identification and tracking is essential to an epidemiological investigation, and if someone intentionally interferes with or rejects the process of confirming this link, it will result in direct, realistic, and widespread interference with the epidemiological investigation. In this article, ① there are differences between an epidemiological investigation and a request for information provision under the Infectious Disease Control and Prevention Act, but there are areas that fall under the epidemiological investigation even in the case of a request for information, ② Considering the medical characteristics of COVID-19 and the continuity of the epidemiological investigation, the epidemiological investigator the fact that the act of requesting a list may fall under the epidemiological investigation, ③ that the offense of obstructing the epidemiological investigation in certain cases may constitute 'obstruction of Performance of Official Duties by Fraudulent Means', and ④ rejecting the request for information provision under the Infectious Disease Control and Prevention Act from September 29, 2020 In this case, it is intended to be helpful in the application of the Infectious Disease control and Prevention Act and the practical operation of epidemiological investigations in the future by pointing out the fact that a new punishment regulation of imprisonment or fine is being implemented.

Evaluation of the Effect of Initial Condition of the Granular Assembly on the Bearing Capacity of the Shallow Foundation using Photoelastic Measurement Technique (광탄성 측정 기법을 이용한 입상체 초기 조건의 얕은 기초 지지력에 대한 영향 평가)

  • Shin, Sang-Young;Jung, Young-Hoon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.3
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    • pp.471-491
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    • 2016
  • Traditional limit equilibrium method needs an assumption of the failure surface to calculate the bearing capapcity of the shallow foundation. From the viewpoint of the mechanics of granular materials, however, the failure of the soil mass is initated by the local buckling of the contact force chains. In this study we observed the directional distribution of the contact force chains in the granular assembly stacked by model particles subjected to the model shallow foundation during loading. Two sets of the assemblies with a regular structure and initially local imperfection were prepared for tests. Existence of the initial local imperfection has a significant effect on the directional distribution of the contact force chains. The bearing capacity of the assembly with local imperfection is only 67% the capacity of the assembly with the regular structure.

Finite element analysis on bio-mechanical behavior of composite bone plate for healing femur fracture considering contact conditions (접촉조건을 고려한 대퇴골 치료용 복합재료 고정판의 생체 역학적 거동에 관한 유한요소해석)

  • Kim, Suk-Hun;Chang, Seung-Hwan
    • Composites Research
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    • v.23 no.1
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    • pp.1-7
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    • 2010
  • In this paper, finite element analyses for estimating the behavior of fractured femur just after the operation were carried out by using ABAQUS 6.71. A stainless steel bone plate and composite bone plates with various stacking angles were considered to find out the effect of bone plate properties on bone fracture healing. In order to simulate the actual state, contact conditions between the plate and bone and fractured bones were imposed on the finite element models and the whole analysis was divided by two steps; screw fastening step and load bearing step. The stress and strain distributions at the fracture site for the cases of the stainless steel and composite bone plates were analyzed and compared with. From the analyses it was found that the composite bone plate had potential advantages for effective bone fractures healing relieving stress shielding effect.

Effect of Damper Between Maglev Vehicles on Curve Negotiation (자기부상열차 차간 댐퍼의 곡선주행에의 효과 분석)

  • Kim, Ki-Jung;Han, Hyung-Suk;Kim, Chang-Hyun;Yang, Seok-Jo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.4
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    • pp.581-587
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    • 2013
  • In a magnetic train set composed of more than two cars, the installation of dampers between cars is carefully considered for improving both the ride quality and the safety, particularly during curve negotiation. In this study, a dynamic simulation of the ride quality and curve negotiation of a Maglev vehicle was carried out. The dynamic model is developed based on multibody dynamics. The presented full vehicle multibody dynamic model integrates the electromagnet model and its control algorithm. By using this model, the effects of the dampers are numerically analyzed. The proposed damper is installed on the vehicle and tested to analyze its effects. In this study, the simulation and measured results of the vehicle behavior and ride quality are discussed.