• Title/Summary/Keyword: Dynamic Method

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Design and Implementation of Communication Mechanism between External Educational Contents and LAMS (LAMS와 외부 교육용 콘텐츠간의 통신 메커니즘의 설계 및 구현)

  • Park, Chan;Jung, Seok-In;Han, Cheol-Dong;Seong, Dong-Ook;Yoo, Jae-Soo;Yoo, Kwan-Hee
    • The Journal of the Korea Contents Association
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    • v.9 no.3
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    • pp.361-371
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    • 2009
  • LAMS(learning activity management system)[1] is one of the useful tools for designing and managing effectively the learning activities such as web search, chat, forum, grouping, and board. Even if LAMS has been upgraded to support the methods for making e-Learning contents conveniently, it does not have a method to communicate with external educational contents (EEC) made by external tools like Flash, Java, Visual C++, and so on. LAMS, which has been operated on Web environment, should manage all EECs like video and dynamic educational contents as educational contents in LAMS database. However, the current LAMS does not support the functionalities which can provide information of EECs to LAMS database and can also access any information about EECs from the database yet. In this paper, we propose the communication mechanism between the LAMS and EECs for solving the problem. In special, the mechanism makes many statistical data by using the information, and provides them for reflecting in education, and can control various learning management that was impossible under the original LAMS. Based on the proposed mechanism, teachers using LAMS can make more various educational contents and can manage them in the system.

Adsorption Characteristics of Toluene Vapor According to Pore Structures of Zeolite 5A Modified with Hydrochloric Acid (산으로 개질한 Zeolite 5A의 세공구조에 따른 Toluene Vapor의 흡착특성)

  • Lee, Song-Woo;Bae, Sang-Kyu;Kwon, Jun-Ho;Na, Young-Soo;An, Chang-Doeuk;Yoon, Young-Sam;Song, Seung-Koo
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.8
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    • pp.807-812
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    • 2005
  • This study is to investigate the correlation of pore structures of Zeolite 5As modified with acid and their adsorption capacity of toluene vapor using the dynamic adsorption method. The experimental results showed that the modification with acid allowed more micropores and enlarged the existing pores. Toluene vapor was mainly adsorbed on the surface of pores over $15\;{\AA}$ in diameter. The equilibrium adsorption capacity of toluene vapor of the modified Zeolite 5As was in the range of $15{\sim}70\;mg/g$ and the equilibrium adsorption capacity was increased to f times than that of the Zeolite 5A. The correlation between the total cumulative surface area and the equilibrium adsorption capacity was hard to say linear. The correlation in diameter between the cumulative surface area in the range of over $15\;{\AA}$ and the equilibrium adsorption capacity gate the highest correlation factor of 0.997.

A Study on the Architectural Environment as a Combination of Performance and Event (퍼포먼스.이벤트의 결합체로서 건축환경연구)

  • 김주미
    • Archives of design research
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    • v.14
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    • pp.121-138
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    • 1996
  • The purpose of this study is to develop a new architectural language and design strategies that would anticipate and incorporate new historical situations and new paradigms to understand the world. It consists of four sections as follows: First, it presents a new interpretation of space, human body, and movement that we find in modern art and tries to combine that new artistic insight with environmental design to provide a theoretical basis for performance-event architecture. Second, it conceives of architectural environment as a combination of space, movement, and probabilistic situations rather than a mere conglomeration of material. It also perceives the environment as a stage for performance and the act of designing as a performance. Third, in this context, man is conceived of as an organic system that responds to, interacts with, and adapts himself to his environment through self-regulation. By the same token, architecture should be a dynamic system that undergoes a constant transformation in its attempt to accommodate human actions and behaviors as he copes with the contemporary philosophy characterized by the principle of uncertainty, fast-changing society, and the new developments in technology. Fourth, the relativistic and organic view-point that constitutes the background for all this is radically different from the causalistic and mechanistic view that characterized the forms and functions of modernistic design. The present study places a great emphases on dematerialistic conception of environment and puts forth a disprogramming method that would accommodate interchangeability in the passage of time and the intertextuality of form and function. In the event, performance-event architecture is a strategy based on the systems world-view that would enable the recovery of man's autonomy and the reconception of his environment as an object of art.

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Lightweight Design of a Vertical Articulated Robot Using Topology Optimization (위상최적화를 이용한 수직 다관절 로봇의 경량 설계)

  • Hong, Seong Ki;Hong, Jung Ki;Kim, Tae Hyun;Park, Jin Kyun;Kim, Sang Hyun;Jang, Gang-Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.36 no.12
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    • pp.1683-1688
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    • 2012
  • Topology optimization is applied for the lightweight design of three main parts of a vertical articulated robot: a base frame, a lower and a upper frame. Design domains for optimization are set as large solid regions that completely embrace the original parts, which are discretized by using three-dimensional solid elements. Design variables are parameterized one-to-one to the material properties of each element by using the SIMP method. The objective of optimization is set as the multi-objective form combining the natural frequencies and mean compliances of a structure for which load steps of interest are selected from the multibody dynamics analysis of a robot. The obtained results of topology optimization are post-processed to designs favorable to manufacturability for casting process. The final optimized results are 11.0% (base frame), 12.0% (lower frame) and 10.0% (upper frame) lighter with similar or even higher static and dynamic stiffnesses than the original models.

Towards Hope Seeking Intervention Based on Individual Experience in Palliative Care (완화돌봄에서 개인 경험에 근거한 희망 중재를 향하여)

  • Kim, Dal-Sook
    • Journal of Hospice and Palliative Care
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    • v.15 no.1
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    • pp.1-9
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    • 2012
  • Purpose: The aim of this study was to discuss challenges for hope seeking intervention based on individual experience (HSIBIE) in palliative care, assuming that hope is an individualized unique, subjective, and dynamic experience. Methods: Literature, including analysis and discussion, was reviewed to identify limitations and ways to develop HSIBIE. Results: This study identified following challenges: 1. Hope was often described and utilized as a standardized unified structure with varying attributes or mono-structure emphasizing a realistic hope, or both of them (relativism vs. monism) in one literature. This challenge is represented as a problem in conceptualization. 2. Few studies discussed various patterns of hope or individuals' unique experiences in palliative care. 3. The HSIBIE and the method for the HSIBIE have been rarely discussed. Conclusion: A problem in conceptualization is often related to fixed ideas formed over a long period and used in a closed circle of scholars and professionals. Therefore, such fixed ideas should be openly challenged with fresh perspectives. The second issue requires a cross-cultural studies of various hope experiences in palliative care, which can be used for effective and appropriate HSIBIE.

Analysis on the Dynamic Responses of Fishing Vessels in a Seaway (파랑중 어선의 동력학 해석)

  • 이희상
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.36 no.1
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    • pp.33-44
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    • 2000
  • Ships in a seaway will encounter dangerous situation, such as slamming, stranding, and capsizing. The number of capsizing is small, but the loss due to them is very large from the viewpoint of human life, property, and the environmental pollution. The number of capsizing of fishing vessels is about 62% of total number of capsizing, and the half of them is originated from the operational mistake in a seaway. So the dynamics and the capsizing phenomena are to be studied, and the guide for the safe operation of a fishing vessel in a seaway are to be specified. The hydrodynamic forces consist of radiation forces (which are due to the motion of a ship), Froude-Krylov forces (which is due to the incoming waves), and diffraction forces (which is due to the wave and ship interaction). These forces are calculated by well-known strip method. Using the calculated forces, the motion of a ship in a regular sea is obtained. In the real seaway, the waves are very irregular, therefore the statistical analysis is very helpful. In this paper, using the results of the motion in a regular seaway and the wave spectrum, the motion in a irregular seaway are obtained and analyzed.

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Change of Fractured Rock Permeability due to Thermo-Mechanical Loading of a Deep Geological Repository for Nuclear Waste - a Study on a Candidate Site in Forsmark, Sweden

  • Min, Ki-Bok;Stephansson, Ove
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2009.06a
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    • pp.187-187
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    • 2009
  • Opening of fractures induced by shear dilation or normal deformation can be a significant source of fracture permeability change in fractured rock, which is important for the performance assessment of geological repositories for spent nuclear fuel. As the repository generates heat and later cools the fluid-carrying ability of the rocks becomes a dynamic variable during the lifespan of the repository. Heating causes expansion of the rock close to the repository and, at the same time, contraction close to the surface. During the cooling phase of the repository, the opposite takes place. Heating and cooling together with the, virgin stress can induce shear dilation of fractures and deformation zones and change the flow field around the repository. The objectives of this work are to examine the contribution of thermal stress to the shear slip of fracture in mid- and far-field around a KBS-3 type of repository and to investigate the effect of evolution of stress on the rock mass permeability. In the first part of this study, zones of fracture shear slip were examined by conducting a three-dimensional, thermo-mechanical analysis of a spent fuel repository model in the size of 2 km $\times$ 2 km $\times$ 800 m. Stress evolutions of importance for fracture shear slip are: (1) comparatively high horizontal compressive thermal stress at the repository level, (2) generation of vertical tensile thermal stress right above the repository, (3) horizontal tensile stress near the surface, which can induce tensile failure, and generation of shear stresses at the comers of the repository. In the second part of the study, fracture data from Forsmark, Sweden is used to establish fracture network models (DFN). Stress paths obtained from the thermo-mechanical analysis were used as boundary conditions in DFN-DEM (Discrete Element Method) analysis of six DFN models at the repository level. Increases of permeability up to a factor of four were observed during thermal loading history and shear dilation of fractures was not recovered after cooling of the repository. An understanding of the stress path and potential areas of slip induced shear dilation and related permeability changes during the lifetime of a repository for spent nuclear fuel is of utmost importance for analysing long-term safety. The result of this study will assist in identifying critical areas around a repository where fracture shear slip is likely to develop. The presentation also includes a brief introduction to the ongoing site investigation on two candidate sites for geological repository in Sweden.

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A Route Search of Urban Traffic Network using Fuzzy Non-Additive Control (퍼지 비가법 제어를 이용한 도시 교통망의 경로 탐색)

  • 이상훈;김성환
    • Journal of Korean Society of Transportation
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    • v.21 no.1
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    • pp.103-113
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    • 2003
  • This paper shows alternative route search and preference route search for the traffic route search, and proposes the use of the fuzzy non-additive controller by the application of AHP(analytic hierarchy process). It is different from classical route search and notices thinking method of human. Appraisal element, weight of route is extracted from basic of the opinion gathering for the driving expert and example of route model was used for the finding of practice utility. Model evaluation was performed attribute membership function making of estimate element, estimate value setting, weight define by the AHP, non additive presentation of weight according to $\lambda$-fuzzy measure and Choquet fuzzy integral. Finally, alternative route search was possible to real time traffic route search for the well variable traffic environment, and preference route search showed reflection of traffic route search disposition for the driver individual. This paper has five important meaning. (1)The approach is similar to the driver's route selection decision process. (2)The approach is able to control of route appraisal criteria for the multiple attribute. (3)The approach makes subjective judgement objective by a non additive. (4)The approach shows dynamic route search for the alternative route search. (5)The approach is able to consider characteristics of individual drivers attributed for the preference route search.

A Study on the Air Foil Journal Bearing Analysis with Perturbed Rarefaction Coefficients

  • Lee, Yong-Bok;Park, Dong-Jin;Kim, Chang-Ho;Jang, Gun-Hee
    • KSTLE International Journal
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    • v.7 no.2
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    • pp.27-34
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    • 2006
  • Knudsen number is the ratio of molecular mean free path versus mm thickness and the criterion to determine the flow form. When its value is lower than 0.01, the flow can be assumed to has no slip boundary condition. And in the case that the value is between 0.01 and 10, then the flow has slip boundary condition at both the adjacent walls. The condition of the air flow between the rotating journal and top foil in the air foil bearing is determined by the rotating speed and load, and the Knudsen number is also varied by those values. Because the molecular mean free path is variable to the pressure and temperature, more exact formulation is necessary to understand and analyze the flow regime. In this study, the analysis considering Knudsen number formulated with those variables (pressure, temperature and mm thickness) was executed. The approximate value was examined using the equation to confirm whether the flow has the slip or no-slip boundary condition. From the analytic investigation, it was decided to range approximately 0.01 to 1.0 and the flow can be supposed to have the slip boundary condition. Under the condition of the slip flow, the static characteristics of the air foil bearing were examined using modified Reynolds equations. The results were compared with those considering no slip condition. It shows that the slip condition makes the flow decelerates and the load carrying capacity decreases compared with no slip condition. And as the bearing number and eccentricity ratio increase, the load carrying capacity also increased at both the cases. From this result, it can be supposed that the bearing torque also increases. In the analysis of the dynamic characteristics, the perturbed Knudsen number was taken into consideration. Because the Knudsen number is expressed as the terms of each variable, the perturbed equation can be simply derived. The results of both cases considering and not considering Knudsen number were compared each other. In the case of the direct terms of the stiffness and damping coefficients, the difference between both cases was little and increased as the bearing number and eccentricity ratio increased. And the cross terms have less or more differences.

Study on WP-IBE compliant Mobile IPSec (WP-IBE 적용 Mobile IPSec 연구)

  • Choi, Cheong Hyeon
    • Journal of Internet Computing and Services
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    • v.14 no.5
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    • pp.11-26
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    • 2013
  • In the wireless Internet, it is so restrictive to use the IPSec. The MIPv4 IPSec's path cannot include wireless links. That is, the IPSec of the wireless Internet cannot protect an entire path of Host-to-Host connection. Also wireless circumstance keeps a path static during the shorter time, nevertheless, the IKE for IPSec SA agreement requires relatively long delay. The certificate management of IPSec PKI security needs too much burden. This means that IPSec of the wireless Internet is so disadvantageous. Our paper is to construct the Mobile IPSec proper to the wireless Internet which provides the host-to-host transport mode service to protect even wireless links as applying excellent WP-IBE scheme. For this, Mobile IPSec requires a dynamic routing over a path with wireless links. FA Forwarding is a routing method for FA to extend the path to a newly formed wireless link. The FA IPSec SA for FA Forwarding is updated to comply the dynamically extended path using Source Routing based Bind Update. To improve the performance of IPSec, we apply efficient and strong future Identity based Weil Pairing Bilinear Elliptic Curve Cryptography called as WP-IBE scheme. Our paper proposes the modified protocols to apply 6 security-related algorithms of WP-IBE into the Mobile IPSec. Particularly we focus on the protocols to be applied to construct ESP Datagram.