• Title/Summary/Keyword: Combined effects

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Seismic evaluation of different types of electrical cabinets in nuclear power plants considering coupling effects: Experimental and numerical study

  • Md Kamrul Hasan Ikbal;Dong Van Nguyen;Seokchul Kim;Dookie Kim
    • Nuclear Engineering and Technology
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    • v.55 no.9
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    • pp.3472-3484
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    • 2023
  • The objective of this research is to assess the seismic performance of different types of electrical cabinets in nuclear power plants. The cabinets under investigation are: (a) Case 1: a short single cabinet; (b) Case 2: a tall single cabinet; (c) Case 3: separated cabinets; and (d) Case 4: a combined cabinet with coupling effects. To accurately capture the real behavior of the cabinet, three-dimensional finite element models are developed using ANSYS with connection non-linearity. Frequency domain decomposition (FDD) is used to determine the dynamic properties of the cabinets from shaking table testing data, and these results are utilized to validate the numerical model. The close match between the experimental and numerical results obtained from the modal analysis demonstrates the accuracy of the numerical model. Subsequently, transient structural analysis is performed on the validated models to explore seismic performance. The results show that the acceleration response of the combined cabinet is lower than the single cabinet and the separated cabinet. This observation suggests that top anchors used to combine two different types of cabinets play a crucial role in assessing the efficiency and seismic resistance of electrical cabinets in a nuclear power plant.

Effects of Dimension, Density and Arrangement of the Unit Cell of the TPMS on Contact and Flow Areas of Combined TPMS Structures (TPMS 단위체의 크기, 밀도 및 배치가 혼합형 TPMS 구조의 접촉 및 유동 면적에 미치는 영향)

  • K. K. Lee;H. Kim;D. G. Ahn
    • Transactions of Materials Processing
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    • v.33 no.4
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    • pp.248-254
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    • 2024
  • The triply periodic minimal surface (TPMS) structure is characterized by a high surface-to-volume (S/V) ratio and the separated internal structure for flow. Combining the different TPMS structures can provide unique flow and strength characteristics. This paper investigates the effects of dimension, density and arrangement of the unit cell of the TPMS on contact and flow areas of combined TPMS structures. Several representative TPMS structures, including primitive, gyroid and diamond structures, are adopted to design gradient and heterogeneous types TPMS structures. The estimation method of contact and flow areas using an image processing technique is proposed. Python software is used to predict contact and flow area. The influence of the combination method of TPMS on contact and flow areas in the contact surface of combined TPMS structures with different shapes is investigated. Based on the results of the investigation, an appropriate combination method of TPMS structures is discussed.

Behaviour of open beam-to-tubular column angle connections under combined loading conditions

  • Liu, Yanzhi;Malaga-Chuquitaype, Christian;Elghazouli, Ahmed Y.
    • Steel and Composite Structures
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    • v.16 no.2
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    • pp.157-185
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    • 2014
  • This paper examines the behaviour of two types of practical open beam-to-tubular column connection details subjected to combined moment, axial and/or shear loads. Detailed continuum finite element models are developed and validated against available experimental results, and extended to deal with flexural, axial and shear load interactions. A numerical investigation is then carried out on the behaviour of selected connections with different stiffness and strength characteristics under various load combination scenarios. The influence of applied levels of axial tensile or compressive loads on the bending stiffness and capacity is examined and discussed. Additionally, the interaction effects between shear forces and co-existing bending and axial loads are examined and shown to be comparatively insignificant in terms of stiffness and capacity in most cases. It is also shown that the range of connections considered in this paper can provide rotational ductility levels in excess of those required under typical design scenarios. Based on these findings, a simplified component-based representation is proposed and described, and its ability to represent the connection response under combined loading is verified using results from detailed numerical simulations.

Development and Evaluation of a Combined Health Promotion Program for Preschool Children (보육시설의 학령전기 아동을 위한 통합 건강증진 프로그램 개발과 평가)

  • Choi, Na-Young;Jeon, Mi-Yang;Seo, Hyun-Mi;Seok, Jeong-Won;Kim, Mi-Seon;Jeong, Hyeon-Cheol
    • Child Health Nursing Research
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    • v.16 no.4
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    • pp.314-323
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    • 2010
  • Purpose: This study was conducted to develop and investigate the effect of a combined health promotion program for preschool children and their parents. Methods: Physical examinations were done for 993 preschoolers in 12 preschools. Their parents (n=727) completed a questionnaire on health status and health knowledge of their children and 35 teachers in preschools completed one on health knowledge of preschoolers. Based on the results of the physical examinations and survey, a combined health promotion program was developed. In order to evaluate the program, 35 teachers and 104 parents participated in the program. The effects of the program were tested and health knowledge before and after the program was analyzed. Results: Health knowledge of parents and teachers increased significantly after attending the combined health promotion program. Conclusion: In order to promote the health of preschoolers, parents and teachers need to participate in combined health programs that provide an opportunity for preschoolers to have a physical examination and their parents to learn about the health care for their children.

Effects of Reclosing for Insulation Coordination in 345kV Combined Transmission Lines (345kV 혼합송전선로에서 재폐로가 절연설계에 미치는 영향)

  • Lee, Jong-Beom;Jung, Chae-Kyun;Lim, Kwang-Sik;Kang, Ji-Won
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.5
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    • pp.847-853
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    • 2010
  • This paper describes switching surge analysis for reclosing decision in 345kV combined transmission line with XLPE power cable. Reclosing operation should be decided based on the detailed technical analysis in combined transmission line because this line includes power cable section which is week on insulation. Insulation of power cable can be breakdown at the week point in case of reclosing moment. Therefore the detailed analysis has to be carried out by considering several conditions such as length ratio of power cable section, arrestor, inserting resistance, charging rate, grounding resistance, etc.. On the other hand sheath voltage on IJ(Insulated Joint) is analyzed to check dangerous condition on cable cover. Analysis is performed by EMTP/ATP. Analysis results show that reclosing can be operated as the single line-to-ground fault occurs on overhead line in 345kV combined transmission line, if the inserting resistance is considered before the operation of main circuit breaker.

Efficacy of Mannatide Combined with Sodium Cantharidate Vitamin B6 in the Treatment of Malignant Pleural Effusions

  • Wang, Li-Zhi;Zhang, Hong-Juan;Song, Ji
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.3913-3916
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    • 2015
  • Objective: To evaluate the efficacy of mannatide combined with sodium cantharidate vitamin B6 in the treatment of malignant pleural effusions. Materials and Methods: Data for 69 patients with malignant pleural effusions who did not receive systemic chemotherapy were collected. Injection into the thorax using mannatide combined with sodium cantharidate vitamin B6 was performed for 37 patients in the experimental group and mannatide combined with cisplatin for 32 patients in the control group. Objective responses, KPS (Karnofsky Scoring) and incidences of side effects between the two groups were compared. Results: 13 patients reached CR (complete response) and 11 PR (partial response) in the experimental group, while 12 patients reached CR and 9 PR in the control group, the difference in overall objective responses between the two groups not being significant (66.7% vs 63.6%, p=0.806). However, improvement of KPS in the experimental group wasgreater than in the control group; total side-effect incidences during the period of treatment were 22.2% (8/36) and 54.5% (18/33), respectively (p=0.006). Conclusions: Regimen of mannatide combined with sodium cantharidate vitamin B6 had better improvement in quality-of-life and symptom relief, with a lower side-effect incidence in treatment of malignant pleural effusions.

Expression of Cyclin B1 mRNA and Protein after Activation in Enucleated Mouse Oocytes

  • Hwang, Seong-Soo;Kim, Chang-Kun;Chung, Young-Chai
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.116-116
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    • 2002
  • Further development of reconstructed embryos may be dependent upon the synchronization of donor nucleus and recipient cytoplasm at cell fusion, To control the synchronization of donor and recipient cells, the enucleated MII arrested oocytes are artificially stimulated prior to embryo reconstruction. Destruction of cyclin B results in the exit of cells from M-phase of cell cycle. This study was designed to investigate the effects of single or combined stimulation affected cyclin B1 mRNA and protein levels in mouse oocytes. The oocyte activation was induced by 7% ethanol or 10$\mu\textrm{g}$/$m\ell$ Ca-ionophore without (single) or with (combined) 10$\mu\textrm{g}$/$m\ell$ cycloheximide. Competitive quantitative PCR for cyclin Bl mRNA and western blot analysis for cyclin B1 protein was preformed in mouse oocytes. Cyclin B1 mRNA level was significantly reduced in single (P<0.05) and combined (P<0.05) stimulation groups. However, this level did not change in non-activated group and increased in intact group. Cyclin B1 protein level was also significantly reduced in both single (P<0.05) and combined (P<0.05) stimulation groups. In conclusion, single and combined stimulation induces the degradation of cyclin B1 mRNA and protein after activation in enucleated mouse oocytes.

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Effects of Dynamic Stretching Exercise Combined with Transcranial Direct Current Stimulation on Lower Extremity Muscle Activity and Jump Performance in Soccer Player (경두개직류자극을 결합한 동적 신장운동이 축구선수의 다리 근활성도와 점프수행력에 미치는 영향)

  • Kim, Jeho
    • Journal of The Korean Society of Integrative Medicine
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    • v.7 no.4
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    • pp.273-282
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    • 2019
  • Purpose : The purpose of this study was to provide the effective method for exercise therapy in soccer player. Methods : 30 soccer players were recruited for subjects. The subjects were divided to dynamic stretching exercise combined tDCS (Group I), dynamic stretching exercise combined Sham-tDCS (Group II) of which 15 subjects were randomly allocated. The subjects were given 3 hour of soccer skill and performance and additionally given 20 minutes of dynamic stretching exercise combined tDCS and sham-tDCS for each group, five times a week, for 6 weeks. Their muscle activity and jump performance were analyzed before the intervention. After 6 weeks of the intervention, the mentioned parameters were measured once more for between-group analysis. Results : Comparative analysis of the muscle activity and jump performance between the groups I and groups II showed statistically significant difference. Conclusion : Such results revealed that dynamic stretching exercise combined with tDCS is effective in muscle activity and jump performance. Based on the current study, more effective program is to be proposed for neurologic and musculoskelectal disorder as well as soccer player. Based on the current study, studies that incorporates various combine of variable is required for development of effective tDCS program.

The Effects of Combined Balance Exercise on Balance in Chronic Stroke Patients (복합적 균형 훈련이 만성 뇌졸중 환자의 균형에 미치는 영향)

  • Choi, You-Jin;Ko, Keun-Bum
    • PNF and Movement
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    • v.18 no.2
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    • pp.195-204
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    • 2020
  • Purpose: The study investigated the effect of combined balance exercise using visual feedback and balance pads in rehabilitation of chronic stroke patients. Methods: The participants were 30 patients diagnosed with stroke who met the study selection criteria. Participants were randomly divided into 3 groups of 10: a balance pad exercise (BPE) group, a visual feedback exercise (VFE) group, and a combined balance exercise (CBE) group. All three groups engaged in 30 minutes of exercise, 3 times per week, for 6 weeks. Results: Pre-test and post-test results were analyzed using the functional reach test (FRT), the Berg balance scale (BBS), the timed up & go test (TUG), and the Korean version of the activities-specific balance confidence (K-ABC) scale. The study yielded the following results. Pre- and post-program FRT measures showed significant differences between the BPE and CBE groups (p < 0.05). BBS, TUG, and K-ABC scores showed clear differences in all three groups. Secondly, the CBE group and the BPE group a differed significantly on the BBS before and after the 6-week program (p < 0.05). Finally, the CBE group and the VFE group differed significantly on the BBS before and after the 6-week program (p < 0.05). Conclusion: The study results indicate that combined balance exercise improves balance more effectively than the balance pad and visual feedback exercises. This finding should help to improve rehabilitation in the future.

Economic Impacts of Agricultural Water Shortages in Korea - A Combined Top-down and Bottom-up Model Analysis - (상·하향 통합모형을 활용한 농업 수자원 부족의 경제적 효과 분석)

  • Lee, Seoung-Ho;Kwon, Oh-Sang;Kang, Sung-Won
    • Journal of Korean Society of Rural Planning
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    • v.23 no.4
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    • pp.111-126
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    • 2017
  • This study analyzes the impacts of agricultural water shortages in Korea using a combined top-down and bottom-up model. A multi-region multi-output agricultural sector model with detailed descriptions of production technologies and water and land resource constraints has been combined with a standard CGE model. The impacts of four different water shortage scenarios were simulated. It is shown that an active adaptation of crop choices occurs in even the regions with relatively abundant water resources in order to respond to the change in relative output prices caused by water shortages. We found that although the losses in production values are not quite large despite water shortages due to the price feedbacks, the loss in GDP is substantial. We show that our combined approach has advantages in deriving region and product specific production effects as well as the overall GDP loss effect of water shortages.