• 산업경영시스템학회지
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• 제17권31호
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• pp.163-176
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• 1994

Over the last few years Total Quality Management (TQM) programs have hem widely adapted by Korean manufacturing firms to improve their productivity, competitive edge and product quality levels. The purpose of this study is to evaluate the level of importance placed on four key TQM factors (customer satisfaction, strong management leadership, continuous improvement, imployee involvement and participation) used during the implementation of korean manufacturing TQM programs and to assess the effectiveness of those key factors in improving the performance of the firms. A Questionaire was developed and sent to senior managers in manufacturing organizations throughout korea. This survey asked qustions regarding 1) the firm's business environment and TQM program development 2) subcomponents of the key factors and 3) the effectiveness of the TQM program at improving the performance of the organization. The survey data were analyzed to determine the degree of correlation between each of the factors and the effectiveness of the TQM programs. This study demonstrated that the TQM programs were instrumental at improving the performance of the firms studied, and that the improvement was positively correlated with the length of time that the program had been implemented and the planned duration of the TQM program implementation. It was found that the person-oriented elements of management leadership and employee involvement were positively correlated and predictive of the success of the TQM Program, while the process-oriented components of customer satisfaction and employee involvement were not useful predictors of the effectiveness of the TQM program implementation.

• Computers and Concrete
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• 제14권1호
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• pp.91-107
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• 2014

Using the principle of damage mechanics, zero-thickness pore pressure cohesive elements (PPCE) are used to simulate the casing-cement interface (CCI) and cement-rock interface (CRI). The traction-separation law describes the emergence and propagation of the PPCE. Mohr-coulomb criteria determines the elastic and plastic condition of cement sheath and rock. The finite element model (FEM) of delamination fractures emergence and propagation along the casing-cement-rock (CCR) interfaces during hydraulic fracturing is established, and the emergence and propagation of fractures along the wellbore axial and circumferential direction are simulated. Regadless of the perforation angle (the angle between the perforation and the max. horizontal principle stress), mirco-annulus will be produced alonge the wellbore circumferential direction when the cementation strength of the CCI and the CRI is less than the rock tensile strength; the delamination fractures are hard to propagate along the horizontal wellbore axial direction; emergence and propagation of delamination fractures are most likely produced on the shallow formation when the in-situ stresses are lower; the failure mode of cement sheath in the deep well is mainly interfaces seperation and body damange caused by cement expansion and contraction, or pressure testing and well shut-in operations.

• 디지털산업정보학회논문지
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• 제7권1호
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• pp.31-39
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• 2011

VoIP service uses packet network of ip-based because that has eavesdropping, interception, illegal user as vulnerable elements. In addition, PSTN of existing telephone network is subordinate line but VoIP service using the ip packet provide mobility. so The user authentication and VoIP user's account service using VoIP has emerged as a problem. To solve the vulnerability of SIP, when you use VoIP services with SIP, this paper has made it possible to authenticate user's terminal by using proxy server and proxy server by using authentication server. In conclusion, sender and receiver are mutually authenticated. In the mutual authentication process, the new session key is distributed after exchanging for the key between sender and receiver. It is proposed to minimize of service delay while the additional authentication. The new session key is able to authenticate about abnormal messages on the phone. This paper has made it possible to solve the vulnerability of existing SIP authentication by using mutual authentication between user and proxy server and suggest efficient VoIP service which simplify authentication procedures through key distribution after authentication.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.757-765
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• 2002

This paper analyzes three theories for land degradation assessment and internationl/domestic methods for land degradation monitoring and assessment. Under the guidance of absolute degradation thought, this paper proposes the technological framework for monitoring and appraising cultivated land degradation based on the 3S technique. We can apply 3S technique and analyze the nature, the environmental, the social, and the economic elements which influence the land utilization and degradation synthetically, to set up the indicator system of the cultivated land degradation monitoring and assessment based on 3S technique; to propose the degradation information extraction methods based on 3S technique; to create the quantitative assessment model and method for land degradation; to analyze the ecological environment response of land use and degradation quantitatively; and to propose the measure, policy and suggestion for solving the land degradation problem from the point of view of land utilization.

• Current Optics and Photonics
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• 제5권3호
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• pp.322-328
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• 2021

In this paper, a pretreatment method for a matrix in convex optimization is proposed to optimize the spectral reconstruction process of a disordered dispersion spectrometer. Unlike the reconstruction process of traditional spectrometers using Fourier transforms, the reconstruction process of disordered dispersion spectrometers involves solving a large-scale matrix equation. However, since the matrices in the matrix equation are obtained through measurement, they contain uncertainties due to out of band signals, background noise, rounding errors, temperature variations and so on. It is difficult to solve such a matrix equation by using ordinary nonstationary iterative methods, owing to instability problems. Although the smoothing Tikhonov regularization approach has the ability to approximatively solve the matrix equation and reconstruct most simple spectral shapes, it still suffers the limitations of reconstructing complex and irregular spectral shapes that are commonly used to distinguish different elements of detected targets with mixed substances by characteristic spectral peaks. Therefore, we propose a special pretreatment method for a matrix in convex optimization, which has been proved to be useful for reducing the condition number of matrices in the equation. In comparison with the reconstructed spectra gotten by the previous ordinary iterative method, the spectra obtained by the pretreatment method show obvious accuracy.

• Geomechanics and Engineering
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• 제35권4호
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• pp.411-424
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• 2023

Reasonable estimates of tunnel lining dislocations in the operation stage, especially under longitudinal differential settlement, are important for the design of waterproof gaskets. In this paper, a modified shell-joint model is proposed to calculate shield tunnel dislocations under longitudinal differential settlement, with the ability to consider the nonlinear shear stiffness of the joint. In the case of shell elements in the model, an elastoplastic damage constitutive model was adopted to describe the nonlinear stress-strain relationship of concrete. After verifying its applicability and correctness against a full-scale tunnel test and a joint shear test, the proposed model was used to analyze the dislocation behaviors of a shield tunnel in Shanghai Metro Line 2 under longitudinal differential settlement. Based on the results, when the tunnel structure is solely subjected to water-earth load, circumferential and longitudinal joint dislocations are all less than 0.1 mm. When the tunnel suffers longitudinal differential settlement and the curvature radius of the differential settlement is less than 300 m, although maximum longitudinal joint dislocation is still less than 0.1 mm, the maximum circumferential joint dislocation is approximately 10.3 mm, which leads to leakage and damage of the tunnel structure. However, with concavo-convex tenons applied to circumferential joints, the maximum dislocation value reduces to 4.5 mm.

• Nuclear Engineering and Technology
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• 제56권4호
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• pp.1480-1489
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• 2024

Displacement cascade behaviors of Ti-6Al-4V alloys are investigated using molecular dynamics (MD) simulation. The embedded atom method (EAM) potential including Ti, Al and V elements is modified by adding Ziegler-Biersack-Littmark (ZBL) potential to describe the short-range interaction among different atoms. The time evolution of displacement cascades at the atomic scale is quantitatively evaluated with the energy of primary knock-on atom (PKA) ranging from 0.5 keV to 15 keV, and that for pure Ti is also computed as a comparison. The effects of temperature and incident direction of PKA are studied in detail. The results show that the temperature reduces the number of surviving Frenkel pairs (FPs), and the incident direction of PKA shows little correlation with them. Furthermore, the increasing temperature promotes the point defects to form clusters but reduces the number of defects due to the accelerated recombination of vacancies and interstitial atoms at relatively high temperature. The cluster fractions of interstitials and vacancies both increase with the PKA energy, whereas the increase of interstitial cluster is slightly larger due to their higher mobility. Compared to pure Ti, the presence of Al and V is beneficial to the formation of interstitial clusters and indirectly hinders the production of vacancy clusters.

• 한국통신학회논문지
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• 제29권7C호
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• pp.1015-1023
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• 2004

임의의 두 노드사이에 전송되는 데이터를 보호하기 위해서 단 대 단 키 설정은 필수적이다. 그러나 동적으로 위상이 변화하고, 동일한 권한을 갖는 노드로 구성되는 Ad-Hoc네트워크 환경에서 선행 키 분배는 비현실적인 가정이다. 본 논문은 Ad-Hoc네트워크에서 미리 키를 분배하지 않고 두 노드사이에 단 대 단 키를 설정하는 방안을 제안한다. 제안하는 방안은 Diffie-Hellman 키교환 방법을 기반으로 한다. 제안하는 방안은 키를 교환하는 과정에서 임의의 해쉬체인 값들을 이용하여 교환되는 Diffie-Hellman값의 위조를 방지한다. 따라서 제안하는 단 대 단 키 설정 방안은 man-in-the-middle공격에 대해 해쉬함수의 안전성만큼 안전하다. 실험결과는 제안된 방안이 선행 키 분배 방법에 비해 키 설정 과정에서 전송되는 메시지 수를 크게 감소시킴을 보여준다. 또한 실험결과를 통해 제안된 방안이 상대적으로 확장성이 높은 것으로 평가되었다.

• 대한간호학회지
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• 제19권2호
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• pp.147-159
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• 1989

The main Purpose of this survey was to identify for elements of an effective hospital infection control program for Korea. Nurses and doctors who had participated in an education program for infection control or were re s ponsible for hospital infection control were selected as data informers. The data were collected from 51 subjects by employing a Delphi technique in a series of three rounds from september 1, 1987, to March 31, 1988. IN each round the responses to questionaires were analyzed and the results were communicated back to the individuals. Finally 32 elements of effective hospital infection control program were reduced to 10 elements. 10 elements are as follows ; 1) Hospital administrator's knowledge of importance and necessity for HIC(hospital infection control) 2) Supporting HIC administratively 3) Constituting infection control committee and role of ICC 4) Developing an eductional program and providing a work manual for the hospital infection control staff 5) Educating and informing medical staff about hospital infection 6) Surveillance for hospital infection 7) Developing patient care technique 8) Controlling the hospital environment 9) Executing regular health examination of all medical staff 10) Recruiting the medical staff sufficiently Three rankings of response rate about 32 elements are as follows ; 1) Hiring a full tim staff member for the HIC(66%) 2) Establishing a hospital policy and standards for the HIC(66%) 3) Activating the infection control committee and taking administrative action to support the ICC(63%) In addition the rankings of importance score by Likert 5 scale are as follows ; 1) Washing hands scrupulously(4.88) 2) Nurses participation as key members of the ICC(4.75) 3) Reviewing and evaluating all ongoing aseptic techniques (4.69) In conclusion, first of all, administrative support must be given to hiring a full time staff member and to organization of infection control committee for the HIC in Korea.

• 감성과학
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• 제7권4호
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• pp.7-17
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• 2004

최근까지 제품디자인에 있어서의 조형요소의 심미성에 관한 연구가 많이 진행되어 왔다. 그러나 기존의 연구는 "심미성 요인이 무엇인가\ulcorner"에 초점을 맞추어 왔을 뿐 각각의 심미적 요소들이 사용자의 심미적 반응에 어떻게 영향을 미치는지에 대해서는 그다지 연구된 바가 없다. 따라서 본 연구는 제품디자인에서 심미성 요소를 내용미와 형태미로 나누어 서로의 상관관계를 파악하고 사용자의 심미적 반응에 어떠한 영향을 미치는지를 알아보는 연구이다. 더욱이 연구의 초점이 내용미 중 전형성을, 형태미 중 균형을 중심으로 서로의 심미적 반응의 영향정도와 관여수준과 국가와 같은 조절변수에 의해 심미적 반응이 어떻게 달라지는지를 검증하고자 하기 위한 연구이다. 본 연구를 통하여 실제로 디자인 현장이나 기업에서 디자인에 있어서 심미적 영향요소를 적용하는 데에 대한 의미 있는 시사점을 제공해주고 디자인의 심미성에 대한 이론적인 체계를 만들어가는 것에 기여하리라 본다. 기여하리라 본다.