• Title/Summary/Keyword: Environmental compatibility

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Estimation of shear strength parameters of lime-cement stabilized granular soils from unconfined compressive tests

  • Azadegan, Omid;Li, Jie;Jafari, S. Hadi
    • Geomechanics and Engineering
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    • v.7 no.3
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    • pp.247-261
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    • 2014
  • Analytical and numerical modeling of soft or problematic soils stabilized with lime and cement require a number of soil parameters which are usually obtained from expensive and time-consuming laboratory experiments. The high shear strength of lime and cement stabilized soils make it extremely difficult to obtain high quality laboratory data in some cases. In this study, an alternative method is proposed, which uses the unconfined compressive strength and estimating functions available in literature to evaluate the shear strength parameters of the treated materials. The estimated properties were applied in finite element model to determine which estimating function is more appropriate for lime and cement treated granular soils. The results show that at the mid-range strength of the stabilized soils, most of applied functions have a good compatibility with laboratory conditions. However, application of some functions at lower or higher strengths would lead to underestimation or overestimation of the unconfined compressive strength.

Globalizing Information Systems Alignment : Strategic Thrust and Local Responsiveness

  • Kim, Gyeung-Min;Cho, Namjae
    • Journal of Information Technology Applications and Management
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    • v.22 no.1
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    • pp.131-152
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    • 2015
  • Environmental differences across countries such as socio-cultural, political, economic, and technological differences require business strategies of multinational corporations to vary business practices across regions. Despite the keen awareness of the necessity for strategic adaptation to local context, IS management and strategy tend to remain similar across countries. One of the reasons is to maintain the stability and compatibility of information technology infrastructure. After a careful observation of retail business practice, this study finds IS strategy should also be highly responsive to the local context. This study shows how information resources including systems architecture, processes, human resources, and national context are interlinked together. Despite global excellence in general systems management, failure in such alignment can be a serious problem in extending competitive advantages across regions. This study aims to reveal issues to be taken care of in order to accomplish global technological alignment. Results of this study provide senior management with guidelines and a framework for aligning IT with regional strategic thrust that can improve local responsiveness of multinational companies.

Surface Ageing Property of Polymer Insulator for Transmission line with Forest Fire Test (H종 주상용 몰드 변압기의 덕크구조에 따른 열해석 특성)

  • Cho, Han-Goo;Kim, Kyang-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.111-111
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    • 2010
  • The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss, but it needs some cooling method because heat radiation between each winding is difficult. In this paper, the temperature distribution and thermal stress analysis of H class 100kVA pole cast resin transformer for power distribution are investigated by FEM program.

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Development of strut-and-tie model and design guidelines for improved joint in decked bulb-tee bridge

  • Li, Lungui;He, Zhiqi;Ma, Zhongguo John;Yao, Lingkan
    • Structural Engineering and Mechanics
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    • v.48 no.2
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    • pp.221-239
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    • 2013
  • This paper focuses on a development of strut-and-tie model (STM) to predict the capacity of an improved longitudinal joint for decked bulb-tee bridge systems. Nine reinforced concrete beam/slab specimens anchored by spliced headed bars with different details were tested. Test results were evaluated and compared with an anticipation of the validated STM. The proposed STM provides a lower bound of the ultimate capacity of the joint zone. It shows that the lap length of headed bars has a significant effect on structural behaviors of the improved joint. To develop a full strength joint, the range of the lap length can be determined by the strength and compatibility requirement. Design recommendations to spliced headed bars, concrete strength, as well as lacer bars in the joint zone are proposed for developing a full strength joint.

Current Status and Prospects of Standard Methods for the Measurements of Air Pollution in Korea (대기오염공정시험법의 체계구축과 개선방향)

  • Kim, Ki-Hyun;Bae, Min-Suk
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.4
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    • pp.439-446
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    • 2013
  • In this research, the present standard analytical methods for the monitoring of air pollution levels established by the Korean Ministry of Environment (KMOE) were examined in reference to the recent outputs of several research projects conducted for their amendments. The evaluation of the two criterion methods between the main (the present guideline) and reference methods (the proposed alternate guideline) was made in terms of authenticity and reliability of the quality assurance (QA) and of compatibility of methods. The results of this comparative evaluation are presented for the analysis of both ambient air and source samples. Based on this analysis, we propose a new direction for the future amendment.

Specification of Governing Factors for High Accurate Prediction of Welding Distortion (용접변형 고정도 예측을 위한 지배인자의 특정)

  • Lee, Jae-Yik;Chang, Kyong-Ho;Kim, You-Chul
    • Journal of Welding and Joining
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    • v.31 no.5
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    • pp.1-6
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    • 2013
  • In carrying out the elastic-plastic analysis, four conditions (equilibrium equation, constitutive equation, condition of compatibility and yield condition) should be satisfied. In welding, the temperature largely changed from a melting temperature to a room temperature. So, yield stress of materials largely changed, too. In particular, yield stress becomes about zero over $700^{\circ}C$. The analysis should be carried out under the condition that equivalent stress generated in temperature increment ${\Delta}T$ did not exceed yield stress of materials at high temperature over $700^{\circ}C$. It should be sufficiently recognized that the obtained results were not reliable if this condition was not satisfied.

Improvement of Biological Control against Bacterial Wilt by the Combination of Biocontrol Agents with Different Mechanisms of Action

  • Kim, Ji-Tae;Kim, Shin-Duk
    • Journal of Applied Biological Chemistry
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    • v.50 no.3
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    • pp.136-143
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    • 2007
  • Despite the increased interests in biological control of soilborne diesease for environmental protection, biological control of bacterial wilt caused by Ralstonia solanacearum have not provided consistent or satisfying results. To enhance the control efficacy and reducing the inconsistency and variability, combinations of specific strains of microorganisms, each having a specific mechanism of control, were applied in this study. More than 30 microorganisms able to reduce the activity of pathogen by specific mechanism of action were identified and tested for their disease suppressive effects. After in vitro compatibility examinations, 21 individual strains and 15 combinations were tested in the greenhouse. Results indicated three-way combinations of different mode of control, TS3-7+A253-16+SKU78 and TS1-5+A100-1+SKU78, enhanced disease suppression by 70%, as compared to 30-50% reduction for their individual treatments. This work suggests that combining multiple traits antagonizing the pathogen improve efficacy of the biocontrol agents against Ralstonia solanacearum.

Analysis of curved multicell box girder assemblages

  • Razaqpur, A. Ghani;Li, Hangang
    • Structural Engineering and Mechanics
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    • v.5 no.1
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    • pp.33-49
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    • 1997
  • A method of analysis is proposed for curved multicell box girder grillages. The method can be used to analyze box girder grillages comprising straight and/or curved segments. Each segment can be modelled by a number of beam elements. Each element has three nodes and the nodal degrees of freedom (DOF) consist of the six DOF for a conventional beam plus DOF to account for torsional warping, distortion, distortional warping, and shear lag. This element is an extension of a straight element that was developed earlier. For a more realistic analysis of the intersection regions of non-colinear box girder segments, the concept of a rigid connector is introduced, and the compatibility requirements between adjoining elements in those regions are discussed. The results of the analysis showed good agreement with the shell finite element results, but the proposed method of analysis needs a fraction of the time and effort compared to the shell finite element analysis.

A Study on the Recycling of Coal Ash as Structural Backfill materials (구조물 뒷채움재로서의 석탄회 활용에 관한 연구)

  • 여유현
    • Journal of Ocean Engineering and Technology
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    • v.14 no.1
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    • pp.74-79
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    • 2000
  • The purpose of this paper is to recycle coal ash as structural backfill materials from electric power plants. Two million tons of coal ash are produced annually. The laboratory test was executed for the basic compatibility as substitution for structural backfill materials and the optimal mixture ratio(fly ash : bottom ash) was decided. In addition the model test was performed using medium scale earth pressure model with small size earth pressure cells model box data logger and some other apparatuses. Mixed coal ash and excellent backfill materials(coheisonless soil SW) were compared in the view of lateral earth pressure variation depending on wall displacement. The reduction of earth pressure when coal ash was used as a bockfill material was monitored comparing to that of cohesionless soil. the cost and environmental pollutants by treating coal ash can be reduced through developing the recycling technology.

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Thruster Attitude Control System for the Ksr-3 (KSR-3 추격기 자세제어 시스템 개발)

  • Jeong,Ho-Rak;Jeon,Sang-Un;Choe,Hyeong-Don
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.1
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    • pp.104-112
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    • 2003
  • This paper introduces a thruster attitude control system for the KSR-III and addresses system configuration, design condition for several components and development systems. These systems were confirmed through environmental tests, compatibility tests with other sub-systems and are planned to launch by this year. After the launch test, it can be redesigned for optimal systems using post-analysis.