• 한국경영정보학회:학술대회논문집
• /
• 한국경영정보학회 2007년도 추계학술대회
• /
• pp.411-416
• /
• 2007

Only a few P3P-based privacy aware systems address the discrepancy between a service provider's privacy policy and the user's typical concerns-hence, putting service usage at risk. Moreover, since users are typically nomadic in pervasive computing services, their specific privacy concerns would dynamically change according to the surrounding context. This leads us to develop a dynamically adjusting P3P-based policy for a personalized, privacy-aware service as a core element of secure pervasive computing. Hence, the purpose of this paper is to propose a pervasive P3P-based negotiation mechanism for privacy control which functions in a dynamic and flexible way.

• 한국산업정보학회논문지
• /
• 제4권4호
• /
• pp.94-99
• /
• 1999

가상 현실 기술은 사용자가 현실과 유사한 방법으로 정보를 공유할 수 있는 방법이다. 가상 현실기술은 인간의 오감을 이용한 사실적인 환경을 제공하고 인터넷 환경에서 사용자는 가상 현실 공간을 공유할 수 있는 장점을 가지고 있다. 이러한 가상 공간을 이용하여 갤러리를 모의 구현하고 갤러리 정보영역에 미술작품의 내용을 음성 데이터베이스로 구성한다. 외부의 사용자는 대리인(avatar)을 통하여 가상현실갤러리에서 미술작품을 감상할 수 있다. 본 논문은 감상자가 미술작품에 근접했을 경우 감상의 질을 높히기 위하여 해상도를 높히고, 큐레이터(curator)를 도입하여 미술작품 감상시 작품의 정보를 음성과 문자 메시지를 출력함으로서 상호 작용성을 높혀 사용자에게 현장감을 증대할 수 있다.

• International Journal of Automotive Technology
• /
• 제6권4호
• /
• pp.391-402
• /
• 2005

Despite its superior braking performance to conventional vehicles on test tracks, the performance of the ABS-equipped car seems disappointing on real highway. The poor braking performance results from questionable design of the human-machine interface(HMI) of the brake system. Force-displacement relation at the brake pedal has a strong effect on the braking performance. Recently developed brake-by-wire (BBW) system may allow us to tailor the force feel at the brake pedal. This study aims at exploring analytical ways of designing human-machine interface of BBW system. In this paper, mathematical models of brake pedal feel for electro-hydraulic BBW (EH-BBW) system are developed, and the braking motion and the characteristics of the driver's leg action are modeled. Based on the dynamic characteristics of the brake pedal and the driver, two new HMI designs for EH-BBW system are proposed. In the designs, BBW system is modeled as a type of master-slave teleoperator. The effectiveness of the proposed designs is investigated using driving simulation.

• 기술혁신연구
• /
• 제12권2호
• /
• pp.127-150
• /
• 2004

This article examines the issue of utilization of research findings from public funded research institutions (PRIs) and universities in Malaysia from the perspective of knowledge flows. Such a perspective is adapted from the literature on innovation and knowledge systems. This representation of innovation in terms of knowledge flows helps us to focus on the managerial dimensions involved in the organization of activities such as research and development (R&D). The paper reveals that there is a dismal rate of adoption of research findings generated from PRIs and universities in Malaysia. It is argued that this poor performance is a consequence of weak research management practices. A framework on the key elements of sound research management is described. The article concludes with a discussion on managerial and policy issues arising from these deficiencies and some suggestions for addressing them.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 추계학술대회논문집
• /
• pp.709-711
• /
• 2006

According as optical storage becomes high-density, numerical aperture increases. Therefore, the shift characteristic of moving parts in an actuator for optical pickup becomes a critical design factor because of decrease in the tilt margin. The tilt angle is maximized when the position of moving parts is in a diagonal direction within a moving range. This is determined by design of structure and magnetic circuit of an actuator. Previous analysis method only predicts linear characteristics of moving parts. However, the result of shift characteristics of the moving parts considering structural and magnetic circuit's nonlinearity following the every position simultaneously shows us more realistic result. Therefore, we present analysis method considering nonlinearity of moving parts' position through FEM package using coupled-field analysis. Then, we will suggest hereafter a design guide by comparing the above results with experimental ones.

• 경영과학
• /
• 제9권1호
• /
• pp.3-15
• /
• 1992

In this paper, we study a manufacturing system of serial stages with general service times, in which the production of each stage and the coordination of stages are controlled by Kanban discipline. This Kanban discipline is modeled as a Discrete Event Dynamic System and a system of recursive equations is applied to study the dynamics of the system. The recursive relationship enables us to compare this Kanban discipline with the other blocking disciplines such as transfer blocking, service blocking, block-and-hold b, and block-and-hold K, and the Kanban is shown to be superior to the other disciplines in terms of makespan and throughput. As a special case, two stages Kanban system is modeled as $C_2/C_2/1/N$ queueing system, and a recursive algorithm is developed to calculate the system performance. In optimizing the system performance, the stochastic optimization approach of Robbins-Monro is employed via perturbation analysis, the way to estimate the stochastic partial derivative based on only one sample trajectory of the system, and the required commuting condition is verified. Then the stochastic convexity result is established to provide second-order optimality condition for this parametric optimization problem.

• Industrial Engineering and Management Systems
• /
• 제16권1호
• /
• pp.44-51
• /
• 2017

In today's competitive environment, supply chain management is a major concern for a company. Two of the key issues in supply chain management are transportation and inventory management. To achieve significant savings, companies should integrate these two issues instead of treating them separately. In this paper we develop a framework for modeling stochastic programming in a supply chain that is subject to demand uncertainty. With reasonable assumptions, two stochastic programming models are presented, respectively, including a single-period and a multi-period situations. Our assumptions allow us to capture the stochastic nature of the problem and translate it into a deterministic model. And then, based on the genetic algorithm and stochastic simulation, a solution method is developed to solve the model. Finally, the computational results are provided to demonstrate the effectiveness of our model and algorithm.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 추계학술대회논문집
• /
• pp.816-821
• /
• 2002

It is getting more important that energy efficiency and manufacturing cost of the electric motor in appliance. The SRM has been alternative choice. But acoustic noise and harshness in this motor was widely known. So this paper had been studied on the noise reduction of a SRM in air conditioner. This works include some parameters regarding to blown noise sources like a reluctance torque ripple, air gap eccentricity, Especially, it was focused on dynamic characteristics of the system based on mechanical viewpoint. It came to successful results. Besides, this gave us a validity of phase excitation in experimental measurements.

• 한국자동차공학회논문집
• /
• 제15권2호
• /
• pp.28-34
• /
• 2007

In design stage of vehicles, the application of virtual durability analysis techniques enables us to cut down the necessary time and cost to carry out various physical experiments. In this study, computer simulations of vehicle suspensions were carried out with DADS program including component flexibility, and the durability analysis of vehicle components was executed with MSC/Fatigue program using the load history obtained from vehicle dynamic simulation. Driving test of a vehicle was also carried out to obtain precise input data for the durability analysis, and the results of virtual durability analysis were compared to those of experiments.

• 한국시스템다이내믹스연구
• /
• 제4권2호
• /
• pp.131-151
• /
• 2003

Traffic congestion stems from the widespread desires of people to purse certain goals that inevitably overload existing roads every day. he a transportation policy, congestion toll system has been implemented in Seoul, since 1996. The growing concerns on whether the system would achieve sustained results in the future motivated us to investigate the effectiveness of this policy. Developing and running the congestion toll simulation model, we find that this policy is not an effective policy in the long m. The paper indicates the power of system dynamics approach as a tool for evaluating complex policy like a congestion toll, and suggest that city transportation policy maker should approach the problem with systems thinking and analyze the effectiveness of policy on the basis of understanding the dynamic relationships among subsystems.