• Title/Summary/Keyword: Fatigue behavior

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Health Behaviors of Nurses at a University Hospital according to Type of Work (일개 대학병원 간호사들의 근무형태에 따른 건강행태)

  • Kwon, Mi-Kyung;Kang, Pock-Soo;Hwang, Tae-Yoon;Lee, Kyeong-Soo
    • Journal of Yeungnam Medical Science
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    • v.24 no.1
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    • pp.55-67
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    • 2007
  • Background : The goal of this study was to examine the health behaviors of nurses and provide basic information on health promotion for nurses. Materials and Methods : A self-administered questionnaire survey was completed by 340 nurses working at a university hospital in Daegu, Korea from March 6 to March 30, 2006. The questionnaire included demographic characteristics, working environment, health behaviors, self-assessed health status, and the practice of health promotion activities according to the work group(shift group vs. non-shift group). Results : There were significant differences in 'regular diet', 'drinking', 'ordinary health management', 'regular exercise', 'leisure activities', 'rest', and 'feeling of fatigue' between the two groups. The score for the practice of health promotion activities of the non-shift group was 121.9, which was higher than the 115.4 for the shift group. By field of practice of health promotion activities, there were significant differences in 'self-realization' and 'nutrition' between the two groups. Conclusion : The shift group did not appear to have enough time to take care of their health. It is therefore important to provide a working environment in which nurses are encouraged to increase their interest and efforts to maintain healthy behaviors. In addition, programs for education and training should be developed to help nurses adopt healthy life styles and enhance their self-esteem.

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A Study on Static and Fatigue Behavior of Restrained Concrete Decks without Rebar by Steel Strap (Steel Strap으로 횡구속된 무철근 바닥판의 정적 및 피로거동 특성 연구)

  • Jo, Byung Wan;Kim, Cheol Hwan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.5
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    • pp.137-147
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    • 2012
  • In the steel-free bridge concrete deck, steel straps are generally used instead of conventional steel rebar while laterally restrained in the perpendicular direction to the traffic in order fir the arching effect of concrete deck. In this paper, the minimum amount of FRP bar is to be suggested based on the structural strength, crack propagation, stress level and others in order to control cracks. As a result of laboratory tests, the structural strength of deck with 0.15 percentage of steel strap showed improved structural strength including ductility. The long-term serviceability of steel strap deck with FRP bar proved to satisfy the requirements and to be structurally stable while showing the amount of crack and residual vertical displacement within the allowable limits after two million cyclic loadings. The structural failure of RC bridge deck is generally caused from the punching shear rather than moment. Therefore, the ultimate load at failure could be estimated using the shear strength formula in the two-way slab based on ACI and AASHTO criteria. However the design criteria tend to underestimate the shear strength since they don't consider the arching effects and nonlinear fracture in bridge deck with lateral confinement. In this paper, an equation to estimate the punching shear strength of steel strap deck is to be developed considering the actual failure geometries and effect of lateral confinement by strap while the results are verified in accordance with laboratory tests.

A Study on the Characteristics of Bridge Bearings Behavior by Finite Element Analysis and Model Test (유한요소 해석과 모형실험을 통한 교량받침의 거동특성 연구)

  • Lee, Jae-Uk;Jung, Hie-Young;Oh, Ju;Park, Jin-Young;Kim, See-Dong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.5
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    • pp.96-106
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    • 2014
  • The increased vibration level of the railway bridge could make significant noise and, also, cause structural damages such as fatigue cracks. Related to these subjects, a spherical elastomeric bridge bearing, which is layered by hemispherical rubber and steel plates, was investigated in terms of its vibration performance. Several different shape factors could be considered by changing the curvature of hemispherical surface and size in rubber and steel plate thicknesses in the manufacturing stage. The performance of the spherical elastomeric bearing for the reduction in vibration was compared with that of the conventional bearing by performing vibration experiments on a scale-downed model. The rubber material characteristics and spherical shape are found to be important parameters in reducing the bridge vibration.

Validation of Nursing Diagnose and Defining Characteristics for Patients with Cerebrovascular Accidents - Home Health Care Nursing (뇌혈관질환자와 관련된 간호진단 및 간호진단별 특성 규명과 타당성 조사연구 - 가정간호 대상자를 중심으로 -)

  • Kim, Hae-Young
    • Journal of Home Health Care Nursing
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    • v.2
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    • pp.35-51
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    • 1995
  • This study was done to define nursing diagnose and to test the validity of the characteristics for patients with cerebrovascular accidents being seen at home by home health care nurses. This study was a descriptive study. The sample consisted of 10 experts(professors and home health care nurses) who had had a variety of experience using nursing diagnoses in clinical practice, and 336 nurse progress notes for 18 patients with cerebrovascular accidents. First, 32 nursing diagnoses were defined by the analysis of 336 nurse progress notes, and ten nursing diagnoses were selected according to a criteria of frequency and four nursing diagnoses from home health care clinical practice. Second, content validity was examined by an expert group which considered the sign / symtoms of the fourteen nursing diagnoses. The instrument used for this was a checklist for sign / symtoms based on the nurse progress notes and literature : Carpenito(1993), Kim Cho Ja et al (1994), Lee Sun Ok et al.(1994), Kim Mae Ja et al. (1992), Seoul University Hospital (1993) , Kim Mi Ja et al. (1991). The data were collected from March 1995 to April 1995. Data were analyzed using Content Validity Incidence where if 80% or more of the expert group agreed, characteristics were defined as a major sign/symtoms, if between 50% and 79% of the expert group agreed with the characteristic it was defined as a minor sign / symtoms. The results of this study are summarized as follows : 1. Thirty-two nursing diagnoses related to patients with cerebrovascular accidents were defined. There was a high frequency for the following : 'Potential for disuse syndrome (61%)', 'Impaired physical mobility(50%)', 'Impaired skin integrity (44.4%)', Potential for aspiration(33.3%)', 'Potential for infection: respiration(33.3%)', 'Self-care deficit : bathing /hygine(27.8%)', 'Ineffective family coping(22.2%)', 'Potential for trauma(22.2%)', 'Alteration in nutrition: less than body requirements(22.2%)'. The following diagnoses were also used in home health care clinical practice : 'Anxiety in family (50%)', 'Caregiver fatigue(27.8%)', 'Ineffective treatment behavior (22.2%)', 'Ineffective Levin tube management and Levin tube feeding(22.2%)'. Fourteen nursing diagnoses were selected. 2. Ten of the nursing diagnoses for patients with cerebrovascular accident were listed as nursing diagnoses by NANDA but four nursing diagnoses were new nursing diagnoses used in home health care clinical practice. 3. Characteristics of the ten Nursing Diagnoses from NANDA were developed from the sign /symtoms in the literature and in the nurse progress notes. These characteristics was verified as major or minor sign / symtoms by the expert group. 4. Characteristics of the four nursing diagnoses used in home health care were not defined by the literature but only by the nurse progress notes and verified as major or minor signs /symtoms by the expert group. On the basis of the findings of this study, the following recommendations are made : 1. Continual study is necessary to identify other signs /symtoms not verified in this study. 2. It is necessary to use verified signs /symtoms in home health care clinical practice. 3. It is necessary to define related factors which define each diagnoses in this study. 4. It is necessary to develop of standardized nursing are plans which include defined signs and symtoms. 5. It is necessary to study the outcomes of the standardized nursing care plans.

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A COMPARATIVE STUDY ON THE VITAL SIGN AND BEHAVIOR APPEARANCE DEPENDING ON THE ROUTE OF FLUMAZENIL ADMINISTRATION IN CONSCIOUS SEDATION BY MIDAZOLAM (Midazolam을 이용한 의식진정시 flumazenil의 투여경로에 따른 생징후 및 행동양상의 비교 연구)

  • Kim, Hyun-Sik;Lee, Chang-Seop;Lee, Sang-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.2
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    • pp.159-167
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    • 2002
  • The purpose of this study was to evaluate the efficacy and safety depending on the route of flumazenil, as an antagonist against midazolam. The subjects of this study were 15 volunteers of $22{\sim}24$ years old. They were sedated with midazolam 0.2mg/Kg intranasal spray, and then 40 minutes after midazolam administration, they were given flumazenil 0.2mg intranasal spray for their reversal. For evaluation of the efficacy and safety of intranasal spray for flumazenil, they were monitored with pulse-oxymeter(Nellcor symphony N-3000, Nellcor Puritan CO. USA) and electric sphygmomanometer (Heartcare 200, National CO. Japan), and were assessed themselves using visual analogue scale(VAS) for tranquilization, sleep, fatigue and attitude. All of these subjects were reduced completely without any undesired situations. The results from this study can be summarized as follows ; 1. Nasaly administered flumazenil using spray device produced much more rapid reduction than intravenously administered flumazenil, but soon after fell in more deep sedated state than intravenously administered flumazenil. 2. There were no considerable side effects or bad influence on vital signs of both nasaly administered flumazenil and intravenously administered flumazenil. These results suggested that the flumazenil administered nasaly using spray device for reversal, we could treat patients safely and effectively under conscious sedation using midazolam administration. But, We will have to research about its optimal dosages for flumazenil, used as intranasal spray for reversal agents against the midazolam by evaluating the blood plasma concentration of midazolam and flumazenil.

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Dietary Behaviors and Consumption of Health Food among the Cancer Patients (암환자들의 식행동과 건강식품 섭취실태에 관한 연구)

  • Kim Yong-Sin;Kim Sang-Yeon;Jung Kyung-Ah;Kwon Soon-Hyung;Chang Yu-Kyung;Park Mi-Hyoun;Hwang Sunng-Joo
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.5
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    • pp.516-523
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    • 2005
  • This study was performed to investigate dietary behaviors and consumption of health food in cancer patients. The subjects were 163 cancer patients recruited from the general hospital in Seoul, Korea. The data were obtained by the structured self administered questionnaire. The mean age of subjects was 51 years. Most of subjects didn't eat the visual fat of meat and chicken skin. The mealtime of the subjects was generally regular and most of subjects had breakfast. The subjects of this survey liked to eat foods with sweet taste but disliked to eat hot, salty and sour taste ones. The preference for fish, marine products and vegetables was high but that for instant foods and frying foods was very low. Most of subjects consumed the foods that is generally known as anticancer foods such as vegetables and fruits. On the other hand, most of subjects didn't intake butter, margarine, and frying foods that is known as risk factors of cancer. The majority of subjects$(84.7\%)$ consumed the health food The main reasons for taking health foods by subjects were to cure disease$(58.0\%)$, to prevent disease$(45.3\%)$, to supply nutrients$(39.3\%)$, to maintain the mental state$(12.7\%)$ and to recover fatigue$(10.7\%)$. Majority of subjects$(66.0\%)$ spent money more than 200,000 won/month to buy health foods. The purchasing channels of health foods by subjects were recommendation by family or friend$(64.0\%)$, by physician/pharmacist$(18.0\%)$ and by nutritionist or dietician(6.0), and advertisement through TV or radio$(12.0\%)$. The types of taking health foods of the subjects were vegetable extracted food$(60.0\%)$, mushrooms$(51.3\%)$, Lactobacillus food$(25.3\%)$, enzyme food$(22.6\%)$ calcium containing food$(20.0\%)$ and so on. The results of the current study show that although many cancer patients already practice healthy dietary behaviors, there is a substantial proportion who do not and most of cancer patients consume health foods.' Further intervention is needed to explore the effect of health foods in cancer patients

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A Study on the Mechanical Properties of AC8A/$Al_2O_3$ Composites. (용탕단조법에 의한 AC8A/$Al_2O_3$ 복합재료의 기계적 성질에 관한 연구)

  • Kim, Ki-Bae;Kim, Kyoung-Min;Cho, Soon-Hyung;Yoon, Eui-Park
    • Journal of Korea Foundry Society
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    • v.11 no.6
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    • pp.475-481
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    • 1991
  • In this study the fabrication technology and mechanical properties of AC8A/$Al_2O_3$ Composites by squeeze casting process were investigated to develope for application as the piston materials that require good friction, wear resistance, and thermal stability. AC8A/$Al_2O_3$ composistes without a porosity and the break of preform were fabricated at the melt temperature of $740^{\circ}C$, the preform temperature of $500^{\circ}C$, and mold temperature of $400^{\circ}C$ under the applied pressure of $1200kg/cm^2$ as the results of the observation of microstructures. As the results of this study, the tensile strength of AC8A/$Al_2O_3$ composites was not increased linearly with $Al_2O_3$ volume fraction and so it seemed not to agree with the rule of mixture, which had been used often in metal matrix composite. Also the tensile strength after thermal fatigue test was little different from that before the test. Consequently it was thought that AC8A/$Al_2O_3$ composites fabricated under our experimental conditions had a good thermal stability and subsequently a good interface bonding. Wear rate(i.e., volume loss per unit sliding distance) of AC8A/$Al_2O_3$ composites was decreased with $Al_2O_3$ volume fraction and the sliding speed at both room temperature and $250^{\circ}C$ and so there was a good correlation between wear rate and hardness. Also the wear rate of AC/8A20% $Al_2O_3$ composities was obtained the value of $1.65cm^3/cm$ at sliding speed of 1.14m/sec as compared with about $3.0\;{\times}10^{-8}cm^3/cm$ hyereutectie Al-Si alloy(Al-16%Si-2%Cu-1%Fe-1%Ni), which applied presently for piston materials. The wear behavior of $Al_2O_3$ composites was observed to a type of abrasive wear by the SEM view of wear surface.

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Lateral-Torsional Buckling Strength of I-girder with Corrugated Steel Webs under Linear Moment Gradient (선형 모멘트 구배가 작용하는 파형강판 I-거더의횡-비틂 좌굴 강도)

  • Moon, Jiho;Lim, Nam-Hyoung;Lee, Hak-Eun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.3A
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    • pp.149-160
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    • 2012
  • Corrugated steel plates have several advantages such as high resistance for shear without stiffeners, minimization of welding process, and high fatigue resistance. To take advantage of these benefits, several researchers have attempted to use corrugated steel plate as a web of I-girders. The lateral-torsional buckling is the major design aspect of such I-girders. However, lateral-torsional buckling of the I-girder with corrugated steel webs still needs to be investigated especially for a real loading condition such as non-uniform bending. This paper investigated the lateral-torsional buckling strength of the I-girder with corrugated steel webs under linear moment gradient by using finite element analysis. From the results, it was found that the buckling behavior of the I-girder with corrugated steel webs differed depending on the number of periods of the corrugation. Also, a simple equation for the moment gradient correction factor of the I-girder with corrugated steel webs was suggested. The inelastic lateral-torsional buckling strength of the I-girder with corrugated steel webs was then discussed based on current design equations for ordinary I-girders and the results of finite element analysis.

An Analytical Study for the Stair Joints Constructed with Prefabricated Form System (선시공 조립식 거푸집 공법을 이용한 계단 접합부의 접합방식에 따른 해석적 연구)

  • Lee, Eun-Jin;Jin, Byung-Chang;Chang, Kug-Kwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.301-304
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    • 2008
  • The stair joints constructed with prefabricated system are general method doing structure design at hinge. If you regarded joints to come in contact with a flight of stairs and a slope of stairs as hinge, the moment performance of joints is not in the least moment, so as the bending moment of the stair case is increased, the reinforcement increase. Also the use is decreased because increasing the joint damage of the vibration & fatigue load. No less the reason constructed with pin the stair joints because the construction efficiency of field work is useable. Recently, they are considering the construction efficiency, while the semi-rigid detail for bending performance of joints is proposed, but for now they don't reflect the detail. Therefore, we proposed that reflecting the method at design semi-rigid joints. We compared the moment performance with the stair joints designed at the rigid joints, semi-rigid joints and pin joints. The nonlinear behavior of staircase core statically indeterminate structure. The result of research is that a bending stiffness modulus bring to reflect the semi-rigid performance, the performance of the semi-rigid joint is better than pin joints, and that is judged the system better seismic and vibration performance because have excellent ductility more than rigid joint.

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Thickness Design of Composite Pavement for Heavy-Duty Roads Considering Cumulative Fatigue Damage in Roller-Compacted Concrete Base (롤러전압콘크리트 기층의 누적피로손상을 고려한 중하중 도로의 복합포장 두께 설계)

  • Kim, Kyoung Su;Kim, Young Kyu;Chhay, Lyhour;Lee, Seung Woo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.4
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    • pp.537-548
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    • 2022
  • It is important to design the pavement thickness considering heavy-duty traffic loads, which can cause excessive stress and strain in the pavement. Port-rear roads and industrial roads have many problems due to early stress in pavement because these have a higher ratio of heavy loads than general roads such as national roads and expressways. Internationally, composite pavement has been widely applied in pavement designs in heavy-duty areas. Composite pavement is established as an economic pavement type that can increase the design life by nearly double compared to that of existing pavement while also decreasing maintenance and user costs. This study suggests a thickness design method for composite pavement using roller-compacted concrete as a base material to ensure long-term serviceability in heavy-duty areas such as port-rear roads and industrial roads. A three-dimensional finite element analysis was conducted to investigate the mechanical behavior and the long-term pavement performance ultimately to suggest a thickness design method that considers changes in the material properties of the roller-compacted concrete (RCC) base layer. In addition, this study presents a user-friendly catalog design method for RCC-base composite pavement considering the concept of linear damage accumulation for each container trailer depending on the season.