• 지식경영연구
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• 제23권3호
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• pp.89-109
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• 2022

많은 기업이 포화한 내수시장을 벗어나 해외시장으로의 진출을 도모하고 있다. 하지만 바이어 발굴 및 컨텍, 대금결제의 위험성, 최근 쟁점이 되는 자국 보호주의 정책의 강화 등 여러 이유로 해외 진출이 어려운 실정이다. 기업의 UN 공공 조달 참여를 장려하기 위하여 여러 노력이 진행되었다. 하지만, UN 공공 조달의 다양한 기회에도 불구하고 여전히 제한된 규모의 기업만이 참여하고 있다. 본 연구에서는 기업의 UN 공공 조달 참여 의향에 영향을 미치는 요인을 기업요인과 제품요인으로 구분하여 설명하였다. 구체적으로 본 연구에서는 UN 공공 조달 참여에 긍정적인 영향을 주는 기업의 사회적 책임과 글로벌 지향성의 중요성을 확인하였다. 이와 함께, UN 공공 조달 참여와 지속가능성 사이의 긍정적인 관계에 관해 설명하였다. 본 연구에서 제시한 요인들은 기업의 UN 공공 조달 참여 의향 수준을 높이며 최종적으로 지속가능성 등 기업의 경쟁력 향상에 중요한 역할을 할 수 있을 것으로 판단된다.

• 대한인간공학회지
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• 제26권2호
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• pp.113-122
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• 2007

In shipbuilding industry, musculoskeletal disorders increase rapidly since 2001. Musculoskeletal disorders was occurred the number of 735 in 2003 and the number of 479 on the whole in 2002 and is increased. About this, it is in progress actively that a lot of research services for problem grasping and technology seminar for prevention of musculoskeletal disorders of shipbuilding industry with KOSHIPA (The Korea Shipbuilding Association) in the center in 2002. But, it is actuality that the research is in many difficulties by absence of basic data in shipbuilding industry that most un-standardization work forms. Therefore, this study analyzed present condition of musculoskeletal disorders to shipbuilding industry that most un-standardization work forms. Also, we analyzed on the subject of the Centering-work that appearance extremely much musculoskeletal disorders.

• 월간포장계
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• 통권259호
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• pp.42-43
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• 2014

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 동계학술발표회 논문집
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• pp.531-532
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• 2009

• IEIE Transactions on Smart Processing and Computing
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• 제2권5호
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• pp.282-296
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• 2013

With the emergence of cloud computing, more and more sensitive user data are outsourced to remote storage servers. The privacy of users' access pattern to the data should be protected to prevent un-trusted storage servers from inferring users' private information or launching stealthy attacks. Meanwhile, the privacy protection schemes should be efficient as cloud users often use thin client devices to access the data. In this paper, we propose a lightweight scheme to protect the privacy of data access pattern. Comparing with existing state-of-the-art solutions, our scheme incurs less communication and computational overhead, requires significantly less storage space at the user side, while consuming similar storage space at the server. Rigorous proofs and extensive evaluations have been conducted to show that the proposed scheme can hide the data access pattern effectively in the long run after a reasonable number of accesses have been made.

• 한국컴퓨터정보학회논문지
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• 제20권10호
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• pp.77-83
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• 2015

This paper suggests heuristic algorithm to obtain optimal solution of minimum number of delay aircraft in airport arrivals/departures problem. This problem can be solved only mathematical optimization method. The proposed algorithm selects the minimum delays capacity in various airport capacities for number of arrivals/departures aircraft in $i^{th}$ time interval (15 minutes). In details, we apply median selection method and left-right selection method. This algorithm can be get the optimal solution of minimum number of delay aircraft for sixes actual experimental data.

• International Journal of Aeronautical and Space Sciences
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• 제16권2호
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• pp.123-136
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• 2015

The present study numerically investigates the effect of shield on the flow characteristics of Hartmann whistle. The flow characteristics of un-shielded Hartmann whistle are compared with whistles of different shield heights 15 mm, 17 mm, 20 mm, 25 mm and 30 mm. The comparison of Mach number contours and transient velocity vectors of shielded Hartmann whistles with un-shielded ones for the same conditions reveal that the presence of shield causes the exiting jet to stick to the wall of the shield without causing spill-over around the cavity inlet, thus sustaining the shock oscillation as seen in the unshielded Hartmann whistle, which has intense flow/shock oscillation and spill-over around the cavity mouth. The velocity vectors indicate jet regurgitance in shielded whistles showing inflow and outflow phases like un-shielded ones with different regurgitant phases. The sinusoidal variation of mass flow rate at the cavity inlet in un-shielded Hartmann whistle indicates jet regurgitance as the primary operating mode with large flow diversion around the cavity mouth whereas the non-sinusoidal behavior in shielded ones represent that the jet regurgitance is not the dominant operating mode. Thus, this paper sufficiently demonstrates the effect of shield in modifying the flow/shock oscillations in the vicinity of the cavity mouth.

• 한국기계가공학회지
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• 제6권2호
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• pp.34-40
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• 2007

Antifatigue failure technology take an important part of current industries. Currently, the shot peening is used for removing the defect from the surface of steel and improving the fatigue strength on surface. Therefore, this paper the effect of compressive residual stress and corrosion of spring steel(SAE 5155)by shot-peening on fatigue crack growth characteristics in stress ratio(R=0.05)was investigated with considering fracture mechanics. By using the methods mentioned above, We arrived at the following conclusions. The fatigue crack growth rate(da/dN) of the shot-peening material was lower than that of the un-peening material. And in stage I, ${\Delta}Kth$, the threshold stress intensity factor, of the shot-peen processed material is high in critical parts unlike the un-peening material. Also m, fatigue crack growth exponent and number of cycle of the shot-peening material was higher than that of the un-peening material. That is concluded from effect of da/dN. Finally fracture of shot-peening material and un-peening material was identified and discussed in this study.

• 한국기계가공학회지
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• 제6권1호
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• pp.62-70
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• 2007

The development of new materials that are light-weight, yet high in strength has become vital to the machinery, aircraft and auto industries. However, there are a lot of problems with developing such materials that require expensive tools, and a great deal of time and effort. Therefore, the improvement of fatigue strength and fatigue life are mainly focused on by adopting residual stress. The fatigue crack growth rate of the Shot-peened material was lower than that of the Un-peened material. And in stage I, threshold stress intensity factor of the shot-peen processed material is high in critical parts unlike the Un-peened material. Also, fatigue crack growth exponent and number of cycle of the Shot-peened material was higher than that of the Un-peened material. That is concluded from effect of da/dN. And Fatigue life shows more improvement in the Shot-peened material than in the Un-peened material. And compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation.

• 한국자동차공학회논문집
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• 제12권1호
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• pp.196-202
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• 2004

The development of new materials with light weight and high strength has become vital to the machinery, aircraft and auto industries. However, there are a lot of problems with developing such materials that require expensive tools, and a great deal of time and effort. Therefore, the improvement of fatigue strength and fatigue life are mainly focused on adopting residual stress(in this thesis). The compressive residual stress was imposed on the surface according to each shot velocity(57, 70, 83, 96 m/sec) based on Shot-peening, which is the method of improving fatigue life and strength. By using the methods mentioned above, the following conclusions have been drawn. 1. The fatigue crack growth rate(da/dN) of the Shot-peened material was lower than that of the Un-peened material. And in stage I, ΔKth, the threshold stress intensity factor, of the shot-peen processed material is high in critical parts unlike the Un-peened material. Also m, fatigue crack growth exponent and number of cycle of the Shot-peened material was higher than that of the Un-peened material. That is concluded from effect of da/dN. 2. Fatigue life shows more improvement in the Shot-peened material than in the Un-peened material. And compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation.