• Journal of Chest Surgery
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• 제30권12호
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• pp.1219-1224
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• 1997

1980년대 이후 임상 폐이식 예가 급속히 증가하고 그 성적도 날로 향상되어, 현재 폐이식술은 말기 폐질환 의 치료 방법으로 선택되어 지고 있으나, 아직도 거부 반응의 조기 발견 및 치료, 적출 폐장의 보존, 감염 관 리, 기관지 문합부 합병증 등 여러 면에서 해결해야 할 과제가 많이 남아 있다. 기관지 문합부 합병증은 다른 장기 이식과는 달리 폐이식에 특이한 것으로, 허혈, 거부 반응, 면역 억제제, 문합 부위의 기계적 손상, 감염 등의 여러 인자가 복합적으로 작용하여 일어난다고 생각되고 있다. 기관지 문합부 합병증을 감소시키기 위한 노력의 하나인 telescoping 기법은 Su Antonio Group에 의해 최근에 다시 소개되어 좋은 성적을 보이고 있다 이 실험은 허혈 상태의 기관 문합부 치유에 있어서 Telescoping 기법의 효과를 평가하기 위해 고안되었다. 방법 : 경부 기관을 주위 조직으로 부터 완전 박리하여 최대한의 허혈 상태를 만든 후 중간 1/3을 절제하여 절제된 기관 절편을 재문합하였는데, 그룹 I에서는 단순 단속 봉합하였고, 그룹 II에서는 telescoping 기법으로 문합하여 문합부에서의 섬유화 정도를 비교 관찰하였다. 결과 ; 양 군에서 평균 생존일, 사망 원인, 원인 불명 또는 혈종에 의한 질식으로 사망한 토끼의 술후 평균 생존 기간, 기관 합병증의 발생 빈도 등이 모두 통계적으로 유의한 차이가 없었음에도 불구하고 telescoping 기법으로 문합한 군에서 수술 조기의 문합부의 섬유화(fibroblast density, collagen formation)가 유의하게 증가 되었으며, 섬유아세포의 band-like fibrous union 현상이 문합부에서 현저하게 관찰되었다.

• 대한토목학회논문집
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• 제31권5D호
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• pp.705-717
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• 2011

타워크레인은 건설현장의 전체 자재인양 중 약 50%의 물량을 인양하는 양중 장비로 그 수는 빠른 속도로 증가하고 있으나, 건설현장에서의 소홀한 안전관리로 타워크레인 관련 안전사고는 매년 지속적으로 발생되고 있는 실정이다. 특히, 텔레스코핑 작업은 타워크레인 설치단계에서 텔레스코핑 케이지를 유압으로 상승시킨 후 생긴 빈 공간에 새로운 마스트를 삽입하여 요구 높이까지 상승시키는 작업으로 고소에서 다수의 작업자가 동시에 작업을 실시하여 추락 및 낙하의 위험성이 존재하는 등 타 작업에 비해 재해사례 비중이 가장 높은 것으로 분석되었다. 본 연구의 목적은 타워크레인 작업 중 특히 위험성이 높은 것으로 조사 및 분석된 텔레스코핑 작업의 안전성 및 생산성을 향상시킬 수 있는 타워크레인 텔레스코핑 자동화기술의 개념모델을 제안하고 이에 대한 안전성 측면에서의 잠재적 성능을 분석함으로써 향후 타워크레인 텔레스코핑 자동화기술 실물 제작을 위한 원천자료를 제공하는 것이다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.9-13
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• 2009

As recent construction projects are bigger and higher, the importance of lifting is increasing. In construction sites tower cranes are an essential lifting equipment covering were than 50% of all construction activities. But due to neglect of safety supervision, tower crane-related accidents are frequently taking place. Since most of construction activities is done in heights, the accidents are more likely to be catastrophic. According to an analysis of the causes of tower crane-related accidents, 49% of all accidents claimed for certain periods($1999{\sim}2003$) occurred in the process of telescoping work. Therefore, this research is conducted with the object of analyzing telescoping work of tower cranes and presenting solutions against safety risk. It is expected that the results of this study can be used as useful basic data or material when preparing for effective safety management for tower cranes.

• 한국안전학회지
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• 제36권1호
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• pp.9-17
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• 2021

This study analyses the load imbalance of the tower crane used in telescoping work for structural safety, owing to the difference in wind speed and balance weight position. This is because wind speed and position of the balance weight have a significant impact on the structural stresses of a tower crane during telescoping work. Therefore, structural analysis was performed on the 290HC model, which is often used at construction sites and has only one cylinder installed. Moreover, two models were classified to determine the load acting on the connecting part of the telescopic cage to slewing platform and the cylinder. Five types of balance weight positions were applied at regular intervals from jibs; moreover, four types of wind load criteria were differently applied. Hence, the telescopic cage columns were destroyed at all balance weight positions at a wind speed of 30 m/s and only at certain locations at a wind speed of 20 m/s. Furthermore, failures occurred for cylinders, torsional, and bending at wind speeds of 30 m/s and 20 m/s, load imbalances above the allowable thresholds considering the safety factor. In addition, the load imbalance in the telescoping work also varied depending on the position of the balance weights. The results of these studies have validated that the current standards of adjusting the appropriate position of the balance weights on the jib are completely valid, with the telescoping work to be executed only at wind speeds of less than equal to 10 m/s.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.83-84
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• 2007

• 디지털산업정보학회논문지
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• 제9권4호
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• pp.103-110
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• 2013

In Information Technology era, various amazing IT technologies, for example Big Data, are appearing and are available as the amount of information increase. The number of counselling for violation of personal data protection is also increasing every year that it amounts to over 160,000 in 2012. According to Korean Privacy Act, in the case of treating unique personal identification information, appropriate measures like encipherment should be taken. The technologies of encipherment are the most basic countermeasures for personal data invasion and the base elements in information technology. So various cryptography algorithms exist and are used for encipherment technology. Therefore studies on safer new cryptography algorithms are executed. Cryptography algorithms started from classical replacement enciphering and developed to computationally secure code to increase complexity. Nowadays, various mathematic theories such as 'factorization into prime factor', 'extracting square root', 'discrete lognormal distribution', 'elliptical interaction curve' are adapted to cryptography algorithms. RSA public key cryptography algorithm which was based on 'factorization into prime factor' is the most representative one. This paper suggests algorithm utilizing telescoping series as a safer cryptography algorithm which can maximize the complexity. Telescoping series is a type of infinite series which can generate various types of function for given value-the plain text. Among these generated functions, one can be selected as a original equation. Some part of this equation can be defined as a key. And then the original equation can be transformed into final equation by improving the complexity of original equation through the command of "FullSimplify" of "Mathematica" software.

• 시스템엔지니어링워크숍
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• 통권2호
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• pp.29-44
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• 2003

• 반도체디스플레이기술학회지
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• 제8권4호
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• pp.21-24
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• 2009

We investigated a nanoscale inertia sensor based on telescoping carbon nanotubes, using classical molecular dynamics simulations. The position of the telescoping nanotubes is controlled by the centrifugal force exerted by the rotation platform, thus, position shifts are determined by the capacitance between carbon nanotubes and the electrode, and the operating frequency of the carbon nanotube oscillator. This measurement system, tracking oscillations of the carbon nanotube oscillator, can be used as the sensor for numerous types of devices, such as motion detectors, accelerometers and acoustic sensors.

• 소음진동
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• 제8권3호
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• pp.494-503
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• 1998

In this paper, in order to analyze dynamic characteristics of an automobile steering system consisting of many components, natural frequencies and transfer functions of each component and the total system are found on a FFT analyzer by experiments. Then, the data are transmitted to a commercial package program, CADA-PC. By analyzing the data, the mode shape of each natural frequency and damping values are obtained. Also, the function of a rubber coupling in column and telescoping effects on system are considered. C.A.E commercial programs are used to compare with the results of experiments. For the finite element modeling, I-DEAS is used. Data processing and post processing are operated on NASTRAN and XL, respectively. The ball-bearing and the linkage of shaft with column are modeled by spring element. Stiffness is modified from the results of experiments. The results of those show close agreement. In the mode shape of total system, wheel mode is dominant at lower frequency, while the column mode is main mode at higher. The role of rubber coupling in vibration isolation is clear on mode shape. Telescoping function makes natural frequency of column changed.

• Advances in nano research
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• 제10권4호
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• pp.339-347
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• 2021

In the framework of the density functional theory combined with the method of non-equilibrium Green functions (DFT + NEGF), the electric transport properties of a one-dimensional nanodevice consisting of telescoping polyprismanes with various types of electrical conductivity were studied. Its transmission spectra, density of state, current-voltage characteristic, and differential conductivity are determined. It was shown that C_[14,17], C_[14,11], C_[14,16], C_[14,10] show a metallic nature, and polyprismanes C_[14,5], C_[14,4] possess semiconductor properties and has a band gap of 0.4 eV and 0.6 eV, respectively. It was found that, when metal C_[14,11], C_[14,10] and semiconductor C_[14,5], C_[14,4] polyprismanes are coaxially connected, a Schottky barrier is formed and a weak diode effect is observed, i.e., manifested valve (rectifying) property of telescoping polyprismanes. The enhancement of this effect occurs in the nanodevices C_[14,17] - C_[14,11] - C_[14,5] and C_[14,16] - C_[14,10] - C_[14,4], which have the properties of nanodiode and back nanodiode, respectively. The simulation results can be useful in creating promising active one-dimensional elements of nanoelectronics.