• Title/Summary/Keyword: Physical Cause

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High Temperature Drying of North American Ginseng for Management Decision Making

  • Bailey, W.G.;Dalfsen, K.B.van;Guo, Y.P.
    • Journal of Ginseng Research
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    • v.27 no.3
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    • pp.141-145
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    • 2003
  • The multi-year production cycle for ginseng can be rapidly depreciated by inferior post-harvest activities. This research examines the character of high temperature drying regimes for North American ginseng root to assist management decision making. The objective is a very rapid drying regime, that will not result in physical or chemical damage to the root and that would not alter the actual dry root weight. Research is presented using drying temperatures of 55, 70 and 105 C. Temperatures above these rapidly cause substantive physical damage to the root samples and seriously compromise the dry root values determined. Temperatures below these behaved quite similar to actual dryer regimes (approximately 38 C). Laboratory results indicate that there are differences between the three temperature regimes tested. Careful usage of the 70 C regime, over a period of two to three days in a convection drying oven, has distinct merit.

Multi-field Coupling Simulation and Experimental Study on Transformer Vibration Caused by DC Bias

  • Wang, Jingang;Gao, Can;Duan, Xu;Mao, Kai
    • Journal of Electrical Engineering and Technology
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    • v.10 no.1
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    • pp.176-187
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    • 2015
  • DC bias will cause abnormal vibration of transformers. Aiming at such a problem, transformer vibration affected by DC bias has been studied combined with transformer core and winding vibration mechanism use multi-physical field simulation software COMSOL in this paper. Furthermore the coupling model of electromagnetic-structural force field has been established, and the variation pattern of inner flux density, distribution of mechanical stress, tension and displacement were analyzed based on the coupling model. Finally, an experiment platform has been built up which was employed to verify the correctness of model.

Effects of Experience and Coping Style on Burnout in Child-Counselors : A Content Analysis (내용분석을 통한 아동상담자의 의욕상실 경험과 대처방식)

  • Park, Hui Hyun
    • Korean Journal of Child Studies
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    • v.29 no.1
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    • pp.207-225
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    • 2008
  • This study used content analysis to explore how experience and coping style affect burnout in child-counselors. Data were self-reports collected by interviews of with 30 child counselors. The contents of the interviews showedthe cause of, psychological and physical responses to, and the ways the subjects coped with burnout. The summarized results are that (1) they experience burnoutwhen they feel incompetent, when counseling is ineffective, when they are under-compensated and when they are poorly supervised, (2) The psychological and physical responses to burnout are diminished self-esteem, depression, incompetence, chilling effect on other fields, and digestive problems. (3) Child-counselorscope with burnout mostly by centering on the problems and by searching for social support.

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Structural Diagnosis in Time Domain on Damage Size (손상크기에 따른 시간영역에서의 구조물 진단)

  • 권대규;임숙정;방두열;이성철
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.259-262
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    • 2002
  • This paper provides the experimental verification of a non-destructive time domain approach to examine structural damage. Time histories of the vibration response of structure were used to identify the presence of damage. Damage in a structure cause changes in the physical coefficients of mass density, elastic modulus and damping coefficient. This paper examines the use of beam like structures with PVDF sensor and PZT actuator to perform identification of those physical parameters, and hence to detect the damage. Experimental results are presented from tests on cantilevered composite beams damaged at different location and with damage of different dimensions. It is demonstrated that the method can sense the presence of damage, and characterize the damage to a satisfactory precision.

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Development of the physical pressure measurement device and orthodontic chair to prevent pressure sores (욕창 예방을 위한 체압 측정 장치 및 교정용 의자 개발)

  • Kang, Dong-Won;Kim, Kyoung-Myoung;Jang, Kyung-Bae
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1974_1975
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    • 2009
  • The chairbound, handicapped person often requires a cushion to distribute the supportive forces over the largest area possible in order to reduce the risk of the development of a pressure sore. Pressure sores are areas of damaged skin caused by staying in one position for too long and can cause serious infections, some of which are life-threatening. When sitting upright, the greatest proportion of body weight is centerd over the ischial tuberosities. So, it is important that comfortable seating and largest distribution of pressure to prevent pressure sores. Therefore, the objective of this study was to develop the physical pressure measurement device and orthodontic chair to prevent pressure sores.

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Characterization of denaturation and renaturation of DNA for DNA hybridization

  • Wang, Xiaofang;Lim, Hyun Jeong;Son, Ahjeong
    • Environmental Analysis Health and Toxicology
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    • v.29
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    • pp.7.1-7.8
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    • 2014
  • Objectives The present study was designed to systematically characterize the denaturation and the renaturation of double stranded DNA (dsDNA), which is suitable for DNA hybridization. Methods A series of physical and chemical denaturation methods were implemented on well-defined 86-bp dsDNA fragment. The degree of each denaturation was measured and the most suitable denaturation method was determined. DNA renaturation tendency was also investigated for the suggested denaturation method. Results Heating, beads mill, and sonication bath did not show any denaturation for 30 minutes. However probe sonication fully denatured DNA in 5 minutes. 1 mol/L sodium hydroxide (alkaline treatment) and 60% dimethyl sulfoxide (DMSO) treatment fully denatured DNA in 2-5 minutes. Conclusions Among all the physical methods applied, the direct probe sonication was the most effective way to denature the DNA fragments. Among chemical methods, 60% DMSO was the most adequate denaturation method since it does not cause full renaturation during DNA hybridization.

On the consideration of the masses of helical springs in damped combined systems consisting of two continua

  • Gurgoze, M.;Zeren, S.;Bicak, M.M.A.
    • Structural Engineering and Mechanics
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    • v.28 no.2
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    • pp.167-188
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    • 2008
  • This study is concerned with the establishment of the characteristic equation of a combined system consisting of a cantilever beam with a tip mass and an in-span visco-elastic helical spring-mass, considering the mass of the helical spring. After obtaining the "exact" characteristic equation of the combined system, by making use of a boundary value problem formulation, the characteristic equation is established via a transfer matrix method, as well. Further, the characteristic equation of a reduced system is obtained as a special case. Then, the characteristic equations are numerically solved for various combinations of the physical parameters. Further, comparison of the results with the massless spring case and the case in which the spring mass is partially considered, reveals the fact that neglecting or considering the mass of the spring partially can cause considerable errors for some combinations of the physical parameters of the system.

A Study of Manhole Bursting due to Surcharged Flow in Large Sewer System (대규모 간선에 있어서 써차지 흐름에 동반되는 맨홀뚜껑 비산현상에 관한 연구)

  • Choi, Sung-Mo
    • Journal of the Korean Society of Hazard Mitigation
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    • v.4 no.2 s.13
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    • pp.53-59
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    • 2004
  • The mechanism of manhole bursting which occurs at excess rainfall events Is studied by using both the physical model and the numerical model (SWMM ; Storm Water Management Model). The result of numerical simulation to steep pressure rising agrees well with that of the physical model at the sewer system under surcharged flow. A cause of manhole bursting is an expansion and spout of the condensed all at manhole that results from the surcharged flow and press wave propagation caused by gate operation or closure of conduit at pumping station.

A Study on Health/Illness Concepts in Hospitalized Children (입원아동이 지각한 건강과 질병개념에 관한 연구)

  • Sung Mi-Hae
    • Child Health Nursing Research
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    • v.7 no.2
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    • pp.149-160
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    • 2001
  • The purpose of this study was to explore the health and illness concepts of hospitalized children. The subjects were 129 hospitalized children from 3 to 12 years old in one general hospital. Data were collected through semistructured interviews by authors. This study was conducted from Jun. 1, 2000 to Dec. 31, 2000. Data were coded and categorized by content analysis. The results were as follows : 1. Perceived health concept were physical well-being, food, exercise, powerfulness, emotional stability, obeidence, cleanliness, sleep and ability of social adaptation. 2. Perceived health behavior to maintain health were food, treatment, exercise, cleanliness, obeidence, sleep, emotional stability, power-fulness and psychological stability, physical well-being. 3. Perceived prevention of illness were food, cleanliness, treatment, exercise, obedience, sleep, powerfulness, psychological stability, emotional stability, recreation and ability of social adaptation. 4. Perceived causes of illness were illness, trauma and food. 5. Perceived treatment of illness were treatment, sleep, rest, food, obedience, emotional stability, psychological stability, cleanliness, exercise and powerfulness.

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Study of the oriental medical literature for 産後風(chan hou feng) (산후풍(産後風)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Min, Byung Ho;Yoo, Dong Youl
    • Journal of Haehwa Medicine
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    • v.13 no.1
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    • pp.159-168
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    • 2004
  • '産後風(chan hou feng)' is a postpartum pain-syndrome which caused by inadequate postpartum health care. Recently '産後風(chan hou feng)' contain some symptoms in relate with dystonia like sleep disorder, tiredness, depression, anxiety etc. According to The International Association for the Study of Pain(IASP) "Pain is an unpleasant sensory and emotinal experience associated with actual or potential tissue damage, or described in terms of such damage". This definition means the pain is related to emotional state as well as physical, Physical and emotional changes are common after childbirth, which can cause pain. The important point in treating its '産後風(chan hou feng)' is that the patient in the postpartum period.

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