• 제목/요약/키워드: Chiu

검색결과 149건 처리시간 0.027초

Crack-controlled design methods of RC beams for ensuring serviceability and reparability

  • Chiu, Chien-Kuo;Saputra, Jodie;Putra, Muhammad Dachreza Tri Kurnia
    • Structural Engineering and Mechanics
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    • 제82권6호
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    • pp.757-770
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    • 2022
  • For the design of flexural and shear crack control for reinforced concrete (RC) beams related to serviceability and reparability ensuring, eight simply-supported normal-strength reinforced concrete (NSRC) beam specimens are tested and the existing high-strength reinforced concrete (HSRC) experimental data are included in the investigation of this work. According to the investigation results of flexural and shear cracks, this works modifies the existing design formulas to determine the spacing of the tensile reinforcement for the flexural crack control of a HSRC/NSRC beam design. Additionally, for a specified shear crack width of 0.4 mm, the allowable stresses of the shear reinforcement are also identified. For the serviceability and reparability ensuring of HSRC/NSRC beams, this works proposes the relationship curves between the maximum flexural width and allowable stress of the tensile reinforcement, and the relationship curves between the shear crack width and allowable shear force that can be used to do the crack width control directly.

A Cluster of Health Symptoms After a Law Enforcement Operation: A Case Study

  • Sophia K. Chiu;Jennifer Hornsby-Myers;Christopher Iverson;Douglas Trout
    • Safety and Health at Work
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    • 제13권4호
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    • pp.507-511
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    • 2022
  • Law enforcement officers (LEOs) often encounter rapidly changing and uncontrolled situations that expose them to various hazards. A law enforcement agency requested an evaluation by the National Institute for Occupational Safety and Health (NIOSH) when multiple LEOs reported illness after executing a search warrant and taking a suspect into custody. NIOSH investigators interviewed LEOs and reviewed medical records, forensic laboratory results for collected evidence, and environmental testing results of samples taken after the operation. Two-thirds (25 of 38) of LEOs who participated in the operation reported ≥1 symptom. Eleven LEOs met a case definition for influenza-like illness (ILI). Members of one unit were more likely to have ILI than non-members (prevalence ratio (PR), 4.1; 95% confidence interval (CI): 1.3-13.0; p = 0.01). Influenza vaccination was associated with a lower prevalence of ILI (PR, 0.2; 95% CI, 0.1-0.9; p = 0.02). Preventing employees from working while ill and annual influenza vaccination might prevent similar occurrences.

하천 표면유속을 이용한 지표유속법과 유속분포법 비교 (Comparison of index velocity method and velocity distribution method using river surface velocity)

  • 이신재;윤영선;조상욱
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2022년도 학술발표회
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    • pp.259-259
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    • 2022
  • 하천에서 측정된 표면유속을 이용하여 유량을 산정하는 방법은 전통적으로는 여러 개의 측선에서 표면유속을 측정하고 해당 단면적을 적용하여 전체의 유량을 산정한다. 이러한 방법은 조사자가 직접 표면유속계를 이용하여 이동하면서 측정해야 하며, 측정에 상당한 시간이 소요된다. 또한 사람이 직접 교량 위, 케이블 등을 통해 측정해야 하므로 위험에 노출될 수 있다. 따라서 실시간 표면유속을 측정하여 무인으로 유량을 산정할 수 있는 방안이 필요하다. 본 연구에서는 최대유속이 발생하는 하나의 지점에서 측정된 표면유속을 이용하여 전체의 유량을 산정할 수 있도록 지표유속법(index velocity method)과 유속분포법(velocity distribution method)을 적용하여 비교하고자 한다. 지표유속법은 최대유속과 평균유속과의 관계식을 작성하여 유량을 산정하는 방식이며, 유속분포법은 Chiu(1987, 1988)의 엔트로피 개념의 유속분포법(개수로 단면에서의 2차원적 유속분포)을 적용하고자 한다. 연구를 위해 사용되는 자료는 8개 지점에서 전자파표면유속계로 측정된 유속 및 유량자료를 이용하였다. 본 연구결과를 활용하여 표면유속을 이용한 자동유량측정시스템을 도입한다면 자동유량측정시설의 설치 및 운영에 있어 기존 수중에 센서를 설치하여 운영하는 것보다 효율적일 것으로 판단된다. 또한 단면형상 및 흐름이 복잡하지 않는 하천에서 활용도가 높을 것으로 판단된다.

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Facebook Users in United Arab Emirates: Underlying the Factors and Demographic Analysis

  • Mansumitrchai, Somkiat;Park, Choo-Hui;Chiu, Candy Lim
    • Asia Marketing Journal
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    • 제16권1호
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    • pp.117-132
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    • 2014
  • This study examined the use of Facebook in United Arab Emirates. There were two objectives of this study. The first purpose was to identify the motive for the use of Facebook among people in U.A.E. This study conducted the survey using both qualitative and quantitative methods. One hundred eighty-three working people were used from the survey. Thirty-five questions identified from the interviews were used for the questionnaire design in quantitative method. Factor analysis showed six factors namely usefulness, usage, reliability, making new friends, ethical issue and openness of information. The total variance explained by all the factors was fifty-two percent. This study also examined the demographic variables whether they would play an important role in using the social network site. The study included two more variables, income and married status, which were not frequently examined by previous studies. MANOVA showed statistical significant differences (p < .01) across six factors. ANOVA results showed that gender variable affected only the factor of openness of information. Males were more likely to share their information compared to females. Income variable affected all the factors except the openness of information. The results showed that high-income people had the highest meanscores on three factors (usage, reliability, making new friends) while low-income people had the highest means on usefulness and ethical factors.Marital status had significant effects on usefulness, reliability, and ethical factors. Married people had the low scores on reliability and ethical factors. Lastly, education variable had no effect on all the factors examined.

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A validation study of the SLTHEN code for hexagonal assemblies of wire-wrapped pins using liquid metal heating experiments

  • Sun Rock Choi;Junkyu Han;Huee-Youl Ye;Jonggan Hong;Won Sik Yang
    • Nuclear Engineering and Technology
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    • 제56권4호
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    • pp.1125-1134
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    • 2024
  • This paper presents a validation study of the subchannel analysis code SLTHEN used for the core thermal-hydraulic design of the Prototype Gen-IV sodium-cooled fast reactor (PGSFR). To assess the performance of the ENERGY model of SLTHEN, four liquid metal heating experiments conducted by ORNL, WARD, and KIT with hexagonal assemblies of wire-wrapped rod bundles were analyzed. These experiments were performed with 19-and 61-pin bundles and varying power distributions of axial and radial peaking factors up to 1.4 and 3.0, respectively. The coolant subchannel temperatures measured at different axial locations were compared with the SLTHEN predictions with the Novendstern, Chiu-Rohsenow-Todreas (CRT), and Cheng-Todreas (CT) correlations for flow split and mixing in wire-wrapped pin bundles. The results showed that the SLTHEN predicts the measured subchannel temperatures reasonably well with root-mean-square errors of ~10 % and maximum errors of ~20 %. It was also observed that the CRT and CT correlations consistently outperform the Novendstern correlation.

TEM investigation of helium bubble evolution in tungsten and ZrC-strengthened tungsten at 800 and 1000℃ under 40keV He+ irradiation

  • I. Ipatova;G. Greaves;D. Terentyev;M.R. Gilbert;Y.-L. Chiu
    • Nuclear Engineering and Technology
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    • 제56권4호
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    • pp.1490-1500
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    • 2024
  • Helium-induced defect nucleation and accumulation in polycrystalline W and W0.5 wt%ZrC (W0.5ZrC) were studied in-situ using the transmission electron microscopy (TEM) combined with 40 keV He+ irradiation at 800 and 1000℃ at the maximum damage level of 1 dpa. Radiation-induced dislocation loops were not observed in the current study. W0.5ZrC was found to be less susceptible to irradiation damage in terms of helium bubble formation and growth, especially at lower temperature (800 ℃) when vacancies were less mobile. The ZrC particles present in the W matrix pin the forming helium bubbles via interaction between C atom and neighbouring W atom at vacancies. This reduces the capability of helium to trap a vacancy which is required to form the bubble core and, as a consequence, delays, the bubble nucleation. At 1000 ℃, significant bubble growth occurred in both materials and all the present bubbles transitioned from spherical to faceted shape, whereas at 800 ℃, the faceted helium bubble population was dominated in W.

Immunohistochemical Study of Steroidogenesis, Proliferation, and Hypoxia-related Proteins in Caprine Corpora Lutea during the Estrous Cycle

  • Chiu, C.H.;Srinivasan, R.;Tseng, T.H.;Chuang, R.F.;Wu, L.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권5호
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    • pp.636-642
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    • 2009
  • The corpus luteum (CL) is a transient endocrine gland that produces progesterone, a product required for the establishment and maintenance of pregnancy. In the absence of pregnancy, the production of progesterone in the CL decreases and the structure itself regresses in size. The life span and function of the CL are regulated by complex interactions between stimulatory (luteotrophic) and inhibitory (luteolytic) mediators. When an ovum is released from a mature follicle, angiogenesis and rapid growth of follicular cells form the CL. The purpose of the present study was to determine whether steroidogenesis, proliferation, and hypoxiarelated proteins are expressed in caprine CL. The expression of proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), and hypoxia-inducible factor $1{\alpha}$ (HIF-$1{\alpha}$) were determined in caprine CL during the estrous cycle. Cytochrome P450 side chain cleavage protein did not vary significantly during the estrous cycle; however, there was an increased expression of $3{\beta}$ -hydroxysteroid dehydrogenase in the early and middle stages, which rapidly decreased in the late stage. The same observations were made with respect to steroidogenic acute regulatory protein. Variations in progesterone content and expression of PCNA, HIF-$1{\alpha}$, and VEGF were consistent with this result. Thus, the steroidogenic proteins, PCNA, HIF-$1{\alpha}$, and VEGF in caprine CL are dependent on the stage of the estrous cycle.

The Study of Taiwan's New Immigrant Children's Mathematics Achievement

  • Lai, Wen-Tsung;Cheng, Lung-Wei;Lu, Chiu-Chu
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제17권1호
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    • pp.29-46
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    • 2013
  • Introduction: According the 2011 Taiwanese Government Statistics, the lower secondary school enrollment number of the new-immigrant-children is about 200,000. As known, most of the new immigrants are from the Southeast Asian countries, such as Vietnam, China, Indonesia, Thailand, the Philippines and Cambodia. In order to satisfy the increasing needs and demands on education of the children of new immigrant (CNI, henceforth), Taiwanese government not only develops, but also puts the after-school learning assistance policy into practice from 2006. Therefore, the main purpose of this study is to explore the mathematics achievement of the CNI after the implementation of the after-school learning assistance policy (AsLA policy, henceforth). Purposes: Firstly, to compare the mathematics achievement of the CNI by countries. Secondly, to compare the mathematics performance among the CNI, the children from high-risk family (CHRF, henceforth) and the children of general families. Samples: The 2,452 samples, selected from two junior high schools located in central Taiwan, include 157 CNI, 522 CHRF. Methods: The main method used in this study is interval fuzzy number (IFN, henceforth) in order to compare the mathematics achievement of the children after the implementation of the AsLA policy from different type of families. Results: To reach the two purposes of this study. We can find the effectiveness of mathematics performance from three group's children of new immigrants, high-risk, general family. Therefore, the results provide one of the ways to review the new immigrant's education policy of after-school learning assistance in Taiwan.

IMAGING THE CIRCUMSTELLAR ENVELOPES AROUND EVOLVED STARS WITH THE SMA

  • HIRANO NAOMI;CHIU PO-JIAN;MULLER SEBASTIEN;TRUNG DINH-V
    • 천문학회지
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    • 제38권2호
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    • pp.219-222
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    • 2005
  • We present the high-resolution (2"-4") images of the molecular envelopes surrounding the evolved stars, V Hya, VY CMa, and ${\pi}^1$ Gru observed with the Submillimeter Array. The CO J=2-1 and 3-2 images of the carbon star V Hya show that the circumstellar structure of this star consists of three kinematic components; there is a flattened disk-like envelope that is expanding with a velocity of ${\~}16 km\;s^{-1}$, the second component is the medium-velocity wind having a deprojected velocity of 40-120 km $s^{-l}$ moving along the disk plane, and the third one is the bipolar molecular jet having an extreme velocity of 70-185 km $s^{-l}$. The axis of this high velocity jet is perpendicular to the plane of the disk-like envelope. We found that the circumstellar structure of the S-star ${\pi}^1$ Gru traced by the CO J =2-1 resembles that of V Hya quite closely; the star is surrounded by the expanding disk-like envelope and is driving the medium-velocity wind along the disk plane. We also obtained the excellent images of VY CMa with the CO and $^{13}CO$ J=2-1 and $SO\;6_5-5_4$ lines. The maps of three molecular lines show that the envelope has a significant velocity gradient in the east-west direction, suggesting that the envelope surrounding VY CMa is also flattened and expanding along its radial direction. The high-resolution images obtained with the SMA show that some AGB stars are associated with the asymmetric mass loss including the equatorial wind and bipolar jet.

Research on Current Execution of Knowledge Management in Taiwan's Medical Organizations

  • Tien, Shiaw-Wen;Liu, Chiu-Yen;Chung, Yi-Chan;Tsai, Chih-Hung;Chen, Ching-Piao
    • International Journal of Quality Innovation
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    • 제9권3호
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    • pp.29-56
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    • 2008
  • Since the execution of National Health Insurance system in Taiwan, the competition of medical industry is becoming more and more severe. The ways the hospital operate knowledge management (KM) concept, combine current human resources and professional knowledge by information techniques and upgrade the competitiveness through reinvention of organizational culture have become the important issues. This research is based on the relationship between KM and organizational operation, integrates the characteristic of medical institutions and framework of medical knowledge cycle and starts the research subject by questionnaires from three dimensions: current situation of KM construction in medical organizations, executive effect of KM activities and the challenges faced by KM; subsequently, from qualitative interview, this research attempts to understand how a medical organization executes and adjusts in the consideration of theory and reality as well as quality and costs when actually operates the organization. This research accesses to KM system application of medical institutions and the empirical executive benefits and difficulties through questionnaires. The research results are as follows: (1) having initial understanding toward current KM establishment of medical institutions; (2) confirming the most important items of KM establishment of medical organizations; (3) understanding the most difficulty which the medical organizations encounter when executing KM; (4) establishing medical knowledge cycle figure of the hospitals receiving interviews. Through case interview, this research profoundly accessed to the actual operation of KM application of medical organizations. The target hospitals intended to try many medical KM measures; however, during to complicated hospital organizations and cultural characteristics, the promotion was not successful and the results were not apparent. The most difficulty was to change the employees’ behavior. The targets believed that only the continuous promotion of KM can allow it to be an important aspect of organizational culture and the competitiveness could constant be upgraded.