• Title/Summary/Keyword: Support conditions

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Ground support performance in deep underground mine with large anisotropic deformation using calibrated numerical simulation (case of mine-H)

  • Hu, Bo;Sharifzadeh, Mostafa;Feng, Xia-Ting;Talebi, Roo;Lou, Jin-Fu
    • Geomechanics and Engineering
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    • v.21 no.6
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    • pp.551-564
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    • 2020
  • High-stress and complex geological conditions impose great challenges to maintain excavation stability during deep underground mining. In this research, large anisotropic deformation and its management by support system at a deep underground mine in Western Australia were simulated through three-dimensional finite-difference model. The ubiquitous-joint model was used and calibrated in FLAC3D to reproduce the deformation and failure characteristics of the excavation based on the field monitoring results. After modeling verification, the roles of mining depth also the intercept angle between excavation axis and foliation orientation on the deformation and damage were studied. Based on the results, quantitative relationships between key factors and damage classifications were presented, which can be used as an engineering tool. Subsequently, the performance of support system installation sequences was simulated and compared at four different scenarios. The results show that, first surface support and then reinforcement installation can obtain a better controlling effect. Finally, the influence of bolt spacing and ring spacing were also discussed. The outcomes obtained in this research may play a meaningful reference for facing the challenges in thin-bedded or foliated ground conditions.

Belly Sting Model Support Interference Effect of NASA Common Research Model at Low Speed Wind Tunnel (저속 풍동시험 시 NASA Common Research Model의 Belly Sting 모형 지지부에 의한 간섭효과에 관한 연구)

  • Cha, Kyunghwan;Kim, Namgyun;Ko, Sungho
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.3
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    • pp.167-174
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    • 2021
  • Computational Fluid Dynamics (CFD) was performed under low-speed wind tunnel test conditions using a 29.7% scale model of the NASA common research model. A wind tunnel test was conducted to measure the aerodynamic coefficient of the CRM with Belly sting model support configuration at a low Reynolds number of 0.3×106 and it was compared with the aerodynamic coefficient of CFD analysis. In order to verify the validation of the analysis, a computational analysis under the conditions of the advance research was performed and compared. The interference effect of the Belly sting model support affected not only the fuselage but also the main and tail wings.

Optimal Pricing Strategies for Open Source Support Providers

  • Kim, Byung Cho
    • Asia pacific journal of information systems
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    • v.23 no.1
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    • pp.1-19
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    • 2013
  • The market for commercial open source software (OSS) has been rapidly growing with the proliferation of OSS. One way to commercialize OSS is the support model, which has been adopted by leading OSS firms such as Red Hat and JBoss. Despite the growing interest in OSS commercialization, little research has provided OSS support providers with a pricing guideline. In this paper, we examine the optimal pricing strategies for OSS support providers. Our benchmark is a monopoly case in which we investigate a startup software vendor's incentive to choose the OSS support regime over the proprietary one. Then we extend the model to a duopoly case in which OSS under the support regime competes against proprietary software. We characterize the conditions under which the OSS support model is viable under competition. We believe that our results offer insights to the OSS vendors who consider commercializing their OSS with a support model.

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A Grounded Theory Approach to the Comfort Experience of Hospitalized Patients (입원대상자의 안위경험에 대한 근거이론적 접근)

  • 김경희;김금순;강규숙;강현숙;김원옥;백훈정;원종순;임난영;정인숙
    • Journal of Korean Academy of Nursing
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    • v.30 no.3
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    • pp.750-763
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    • 2000
  • This study is based on grounded theory methodology by Strauss & Corbin(1998). Ten hospitalized subjects were interviewed for data collection. In the process of data analysis, 'acceptance' is found to be the causal condition, while 'health professionals' skillfulness', 'ward environment', 'history of hospitalization', and 'general conditions' were identified as context, 'felling of relief' as the core phenomenon, 'self-efficacy', 'support of others', and 'life style' as the intermediate situation, 'passive reaction', 'alternative reaction' and 'active reaction' as the strategy and 'stabilization', 'satisfaction', 'hope' and 'carrying out' as consequences. 'Feeling of relief' is found to go through the three stages of recognition-generation-maintenance after the five different patterns. 1) In case the health professionals are skillful, the ward environment is favorable, the general conditions of the patients improved and as a result the feeling of relief is strong, during the first hospitalization, the self-efficacy of the subjects tends to be strong. They proceed toward the goal set for themselves with a renewed hope and active or alternative reaction toward the feeling of relief. 2) The subjects tend to proceed toward the goal set for themselves with a renewed hope and active and alternative reaction toward the feeling of relief in case health professionals are skillful, the ward environment is favorable the general conditions of the subjects improved, self-efficacy is strong, and lifestyle is autonomous, during the second hospitalization even though support of others is merely superficial. 3) The subjects tend to stabilize, and satisfy themselves with the given situation with passive and alternative reaction to the feeling of relief in case health professionals are skillful and the ward environment is favorable but the general conditions worsened and accordingly the feeling of relief, is weak and life style is dependent during the second hospitalization although the subjects' self-efficacy is strong and support of others is specific. 4) The subjects tend to stabilize and satisfy themselves with the given situation with passive and alternative reaction to the feeling of relief in case health professionals are unskillful the ward environment is unfavorable, the general conditions improved, support of others is specific but life style is dependent and self-efficacy is weak during the first hospitalization. 5) The subjects tend to stabilize and satisfy themselves with the given situation in case health professionals are unskillful the ward environment is unfavorable but the general conditions improved support of others is specific and as a result self-efficacy is strong but life style is dependent.

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The Effect of Types of Weight-Bearing Surfaces on Muscle Activities of Lower Limbs and Weight Distribution During Semi-Squat Movement of Patients With Hemiplegia (편마비 환자의 반 쪼그려 앉기(semi-squat)동작 시 양하지 지지면의 형태가 하지 근활성도와 체중분포에 미치는 영향)

  • Yang, Yong-Pil;Roh, Jung-Suk
    • Physical Therapy Korea
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    • v.19 no.1
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    • pp.28-36
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    • 2012
  • This study used an unstable platform to change the support surface type and position of both lower limbs in order to determine changes in weight distribution and muscle including the vastus medialis, tibialis anterior, lateral hamstring, and lateral gastrocnemius of both lower limbs were evaluated during knee joint flexing and extending in a semi-squat movement in 32 hemiplegic patients. The support surface conditions applied to the lower limbs were divided into four categories: condition 1 had a stable platform for both lower limbs; condition 2 had an unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side; condition 3 had a stable platform for the non-hemiplegic side and an unstable platform for the hemiplegic side; and condition 4 had an unstable platform for both sides. The normalized EMG activity levels of muscles and weight bearing ratio of both sides in the four surface conditions were compared using repeated measures ANOVA. A significant increase was found in the weight support distribution for the hemiplegic side in flexing and extending sessions in condition 2 compared to the other conditions (p<.05). A statistically significant decrease in significant decrease in asymmetrical weight bearing in flexing and extending sessions was observed for condition 2 compared to the other conditions (p<.05). A similar significant decrease was found in differences in muscular activity for both lower limbs in condition 2 (p<.05). The muscular activity of the hemiplegic side, based on the support surface for each muscle showed a significantly greater increase in condition 2 (p<.05). An unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side therefore increased symmetry in terms of the weight support distribution rate and muscle activity of lower limbs in hemiplegic patients. The problem of postural control due to asymmetry in hemiplegic patients should be further studied with the aim of developing continuous effects of functional training based on the type and position of the support surfaces and functional improvement.

The Reciprocity of Intergenerational Support Exchange and its Characteristics - Analyzing Data on Elders in Seoul Area (세대간 지원교환의 호혜성에 관한 연구: 서울지역 노인자료의 분석)

  • Cheong, Byeong-Eun
    • 한국노년학
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    • v.27 no.2
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    • pp.503-518
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    • 2007
  • The intergenerational support exchange depends on elder's objective conditions and social context, and its effects are diverse. I argue that not only capacity such as health condition and economic status but also relational properties among parent(s) and adult children are important to determine their reciprocal support exchange. Seoul area is selected, and 730 elders are interviewed to be analyzed quantitatively. The survey data are collected based on the structured questionnaire. Findings are partly supportive to the arguments presented above. The relational properties, especially coresidence, the number of adult children, and contact frequency independently influence reciprocal support. The better health conditions of parent(s) are, the more support to adult children is given. The economic status is related to financial support exchange only. The types of intergenerational support exchange include dependant, balanced, and generalized reciprocity. The most important determinant of the reciprocity is the elders' health condition.

APPROXIMATE SOLUTIONS TO ONE-DIMENSIONAL BACKWARD HEAT CONDUCTION PROBLEM USING LEAST SQUARES SUPPORT VECTOR MACHINES

  • Wu, Ziku;Li, Fule;Kwak, Do Young
    • Journal of the Chungcheong Mathematical Society
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    • v.29 no.4
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    • pp.631-642
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    • 2016
  • This article deals with one-dimension backward heat conduction problem (BHCP). A new approach based on least squares support vector machines (LS-SVM) is proposed for obtaining their approximate solutions. The approximate solution is presented in closed form by means of LS-SVM, whose parameters are adjusted to minimize an appropriate error function. The approximate solution consists of two parts. The first part is a known function that satisfies initial and boundary conditions. The other is a product of two terms. One term is known function which has zero boundary and initial conditions, another term is unknown which is related to kernel functions. This method has been successfully tested on practical examples and has yielded higher accuracy and stable solutions.

Structural Weld Strength Analysis on Door Hinge of Field Artillery Ammunition Support Vehicle (자주포용 탄약 운반 궤도차량 도어힌지 용접부 구조강도 해석)

  • Kang, Hyeon-Je;Kim, Byeong-Ho;Kim, Byung-Hyun;Seo, Jae-Hyun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.3
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    • pp.58-65
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    • 2016
  • This study analyzed the structural weld strength for a door hinge for a field artillery ammunition support vehicle. In order to determine the optimal conditions, we measured the modal analysis and analyzed the leg length of a rear door hinge. From these methods, we acquired the vibration frequency of normal mode and the optimal welding leg length conditions. It was possible to obtain a structural stability for a rear door hinge of the field artillery ammunition support vehicle. In the future, this should be used as a reference source for the weld strength analysis of high vibration and high weight structures for another welding system design.

Knowledge-Based Approach Using Support Vector Machine for Transmission Line Distance Relay Co-ordination

  • Ravikumar, B.;Thukaram, D.;Khincha, H.P.
    • Journal of Electrical Engineering and Technology
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    • v.3 no.3
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    • pp.363-372
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    • 2008
  • In this paper, knowledge-based approach using Support Vector Machines (SVMs) are used for estimating the coordinated zonal settings of a distance relay. The approach depends on the detailed simulation studies of apparent impedance loci as seen by distance relay during disturbance, considering various operating conditions including fault resistance. In a distance relay, the impedance loci given at the relay location is obtained from extensive transient stability studies. SVMs are used as a pattern classifier for obtaining distance relay co-ordination. The scheme utilizes the apparent impedance values observed during a fault as inputs. An improved performance with the use of SVMs, keeping the reach when faced with different fault conditions as well as system power flow changes, are illustrated with an equivalent 265 bus system of a practical Indian Western Grid.

Effects of Foundation Stiffness on the Stability of Supercritical Driveshafts (고속 구동축의 지지부강성이 안정성에 미치는 영향)

  • Shin, Eung-Soo;Kim, Tai-Gwang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.04a
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    • pp.603-607
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    • 2008
  • This paper is to investigate the effects of support conditions on the whirling stability of a supercritical composite driveshaft. Two system parameters are rigorously considered: one is the bending stiffness of the support beam/bearings and the other is the rotating internal damping of the shaft. An analytic model is developed based on finite element methods and an eigenvalue analysis is employed to estimate the shaft stability under supercritical operating conditions. Results show that the internal damping causes the whirling instability at a supercritical speed, as demonstrated in other previous studies. However, the bending stiffness of the support beam is found to affect greatly the stability behaviors of a supercritical shaft and several combinations of the shaft/beam stiffness can be identified to guarantee the stable operation even in a supercritical region.

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