• 제목/요약/키워드: internal stability

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예비보육교사들이 지각한 교직윤리의식이 교사효능감과 전문성인식에 미치는 영향 (The Influence of the Teaching Ethics Perceived by Preservice Childcare Teachers on Teacher Efficacy and Professionalism Awareness)

  • 김영태
    • 한국산학기술학회논문지
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    • 제16권10호
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    • pp.6779-6787
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    • 2015
  • 이 연구의 목적은 예비보육교사들의 교직윤리의식이 교사효능감과 전문성인식에 영향을 미치는 요인은 무엇인지를 알아보고자 하였다. 이러한 연구목적으로 A시에 소재한 예비보육교사 285명을 대상으로 질문지를 사용하여 실시하였다. 연구결과는 첫째, 예비보육교사들이 지각한 교직윤리의식은 영유아에 대한 윤리가, 교사효능감에서는 교수전략이, 전문성인식은 사회봉사와 직업윤리가 가장 높게 인식하는 것으로 나타났다. 둘째, 예비보육교사들의 교직윤리의식, 교사효능감, 전문성인식에서 통계적으로 유의미한 상관관계가 있는 것으로 나타났다. 셋째, 예비유아교사들의 교직윤리의식이 교사효능감과 전문성인식에 긍정적인 영향을 미치는 것으로 나타났다. 본 연구결과로 볼 때, 예비보육교사의 교직윤리의식의 중요성을 인식하고 질 높은 보육서비스 향상을 위하여 교사효능감과 전문성인식이 형성될 수 있도록 체계적인 보육교사 교육의 내실화를 마련하는데 다양한 연구가 진행되어야 할 것으로 사료된다.

K-55A1 자주포 급속장전장치의 장전신뢰성 향상에 관한 연구 (A Study on the Increase of the Reliability of the Flick Rammer on K-55A1 Self Propelled Artillery)

  • 나라별;김병현;이주승;김병호
    • 한국산학기술학회논문지
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    • 제19권9호
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    • pp.62-68
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    • 2018
  • 본 연구는 군 포병 전력의 핵심 장비인 자주포의 급속장전장치에 장착된 밀대 시스템 개선을 통해 탄의 장전 안정성향상을 목표로 하는 것이다. 종래의 자주포에는 수동 장전장치가 적용되어 있었다. 군에서 운용하는 장비의 현대화와 연속사격 속도 향상을 위해 급속 장전장치를 설치하였으며, 이러한 급속 장전장치를 통해 탄이 장전되는 과정에서 약실 내부와 간섭되는 현상을 줄이고, 비행시간을 감소하도록 설계되었다. 그러나 기본적으로 밀대를 통해 탄의 급속장전이 이루어지는 슈팅 방식의 장전시스템에서는 탄 흐름(fall-back) 현상이 간헐적으로 발생할 수 있다고 보고되고 있다. 그래서 이러한 문제를 해결하기 위해서 장전 과정의 실제 조건을 반영한 전산모사(C.A.E.)를 통해 탄이 장전되는 과정에서 비행 거리를 감소시키면 탄 흐름 현상을 방지할 수 있는 것을 이론적으로 확인 하였고, 탄의 비행거리를 줄이는 최적의 설계 방안을 도출하였다. 최종적으로 이러한 결과를 바탕으로 야전에 배치된 자주포에 장착하여 시험한 결과 개선효과가 있음을 확인하였다.

보완대체요법에 대한 당뇨병환자의 인식 및 이용현황 (Perception and Use of Complementary and Alternative Medicine in Diabetic Patients in Busan Area)

  • 김혜령;손은주;김미경;류은순
    • 대한지역사회영양학회지
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    • 제16권4호
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    • pp.488-496
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    • 2011
  • The purpose of this study was to investigate the perception and utilization of Complementary and Alternative Medicine (CAM) for diabetic patients in Busan. The subjects were 227 patients at two general hospitals (over 400 bed). This study was performed through the interviewing process using questionnaires conducted from January to April, 2010. Of a total of subjects, 109 patients (48.0%) had taken CAM at least one time. The patients used CAM recognized that they were 'auxiliary medicines' (39.4%), 'supplementary health foods' (32.1%) and 'medicines' (19.3%), but inexperienced patients perceived them as 'supplementary health foods' (29.6%), 'unscientific treatment' (22.6%) and 'medicines' (20.2%), It was significantly different between two groups of patients (p < 0.001). The number of CAM types used for the patients was 51. The CAM types were plant foods (64.3%), dietary supplement (23.6%) and animal diets (12.1%). The patients used an average of 5.9 different kinds of CAM and an average of 3.8 years them and paid \93,345 per month. The patients with diabetic complications and for longer morbidity periods used CAM for significantly (p < 0.05) longer periods. The mean effectiveness scores of the patients used CAM were 3.31/5.00 for efficacy satisfaction, 3.58/5.00 for fewer side effects compared to those of oral drugs, 3.60/5.00 for psychological stability, 3.81/5.00 for easiness to use, and 3.06/5.00 for economic satisfaction. Of the patients that used CAM, 55.9% did not consult with doctors about CAM. More than two-thirds of the patients (77.1%) did not feel the need to consult with doctors.

호텔주방의 HACCP 시스템적용 유무에 따른 조리종사원의 직무스트레스, 만족, 몰입의 비교 분석 (A Comparative Study of Job Stress, Satisfaction and Commitment of Cooking Employees in Hotel Kitchens with and without HACCP Systems)

  • 민경천;홍완수
    • 대한지역사회영양학회지
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    • 제23권1호
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    • pp.28-37
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    • 2018
  • Objectives: This study was conducted to identify differences in job stress, satisfaction and commitment of cooking employees working in hotel kitchens with and without HACCP systems. Methods: Culinary employees of 12 five-star hotels were surveyed and 504 valid data were used for SPSS analysis. Sub factors of working environment factors (job stress, job satisfaction, and job commitment) were examined for analysis. Results: The results showed that hotels that implemented the HACCP system had significantly higher values for the five sub factors of employee job stress (job demand, relationship conflict, organizational system, lack of job autonomy, and job instability; p<0.001). For the sub factors of job satisfaction (internal and external satisfaction) statistic showed a statistically significant value in hotels that did not implement the HACCP system (p<0.001). Job attachment and job importance, which are sub factors of job commitment, showed no difference in relation to the implementation of HACCP system, and job responsibility showed a higher p-value in hotels that did not implement HACCP (p<0.05). Conclusions: The results of the study indicate that culinary employees working at venues with HACCP systems have more job related stress, lower job satisfaction and partially less job commitment. Based on this outcome, venues that have already implemented or are planning to implement HACCP systems should consider the implications regarding their management of employees. Managerial policies that enhance autonomy, job stability, achievement, self-development, promotion, and compensation should also be implemented. Finally, meticulous attention and high investments into the work environment and human resources are necessary.

Properties of Charcoal Board Manufactured from Domestic Wood Waste

  • Seo, In-Su;Lee, Hwa-Hyoung
    • 한국가구학회지
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    • 제21권3호
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    • pp.237-247
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    • 2010
  • This research was carried out to examine the properties of black charcoal board, in order to find the proper manufacturing condition for the black charcoal-board made of the charcoal. The charcoal in this study was distillated from domestic wood waste, and it were also the purpose of this study to see if the black charcoal-board has the advantageous properties of charcoal as a well-being building material against the sick house problem. Domestic wood waste was consisted of MDF 40%, PB 30%, plywood 15% and wood 15%, respectively. Black charcoal board was produced by hot pressing with following conditions; temperature $170^{\circ}C$, three stage pressing cycle of $40-10-40\;kgf/cm^2$(1min.-2.5min.-5min.) and non formaldehyde adhesives [P15%+M5%:MDI(M), poly vinyl acetate emulsion(P). Fine mixed particle size [#6-12(16.9%), #12-18(16.7%), #12-40(47.2%), #40-60(9.5%), #60-100(5.9%), less than #100(3.8%)] gave better results than larger particle size [over #6(33.8%), #12-18(17.7%), #12-40(37.7%), #40-60(6.4%), #60-100(2.6%), less than #100(1.8%)]. Final moisture content of the mat was best at 36%. Black charcoal-board showed less MOR and IB(internal bond), more WA(water absorption) than that of white charcoal-board. Black charcoal board showed not only the same gas adsorption and dimensional stability as white charcoal board but also good cutting, nailing and drilling for indoor environment systems.

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초고강도 강판 성형 시의 스프링백 해석 및 금형 소재 적합성 검토 (Analysis of Springback and Die Material Suitability in the UHSS Sheet Forming Process)

  • 오인석;윤동렬;조준행;이명규;김헌영;김형종
    • 소성∙가공
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    • 제29권4호
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    • pp.203-210
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    • 2020
  • In this study, formability and springback behavior of 1.5 GPa grade ultra-high strength steel (UHSS) sheet were predicted through the finite element simulation, and structural stability of the forming dies was verified by the coupled forming-structural analysis. Uniaxial tension and uniaxial tension-compression tests were performed to obtain experimental data for modeling the springback properties of the sheet material. The springback values predicted by simulation were compared with those from actual measurements. The results calculated from the kinematic hardening model were found to be much more accurate than those from the isotropic hardening model. Deformation of the forming die and springback of the product were calculated by the coupled forming-structural analysis. The higher the strength of the die material, the smaller the surface displacement of the die and the springback of the product. The internal stresses of the dies made of three materials, FC300, FCD550 and STD11 were compared with the yield stress of each material. The results provided a basis for determining the most suitable material for each part of the die set. As a result, simulation techniques have been established for predicting formability and springback in the UHSS sheet forming process.

BES 기법을 이용한 자연환기식 육계사의 난방에너지 분석 (Analysis of Heating Load of a Naturally Ventilated Broiler House using BES Simulation)

  • 홍세운;이인복;홍희기;서일환;황현섭;;유재인;권경석;하태환;김기성
    • 한국농공학회논문집
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    • 제50권1호
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    • pp.39-47
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    • 2008
  • Most of the broiler houses in Korea have experienced problems on controlling the environmental conditions such as suitability, stability and uniformity of rearing condition inside the broiler house. It is very critical which if not properly controlled, would cause serious stress on the chickens. It is therefore urgent to develop optimum designs of naturally ventilated broiler house which is appropriate to the four seasons of Korea. Field experiment for this matter is very difficult to conduct due to the unpredictable and uncontrollable weather condition. In this study, the heating load of a naturally ventilated broiler house was calculated using TRANSYS 15 BES program while internal climate and thermal condition were computed using Fluent 6.2. The computed resulted of the conventional ventilation system (A) and upgraded ventilation system (B) (Seo et al, 2007) were compared with each other for cold season. The results of the Building Energy Simulation(BES) indicated that the system B, the upgraded ventilation system made 8% lower total heating load and 47% lower at only the broiler zone compared to the conventional broiler house. Considering the entire broiler house, the existence of middle ceiling made the heating energy 11% lower required than without middle ceiling. Accordingly, the system B with middle ceiling was found to save heating energy by 20% in average. This study showed that the BES program can be a very powerful to effectively compute the energy loads of agricultural building while the energy load is very close related to ventilation efficiency.

진동을 이용한 몸통 근력 운동이 몸통근 두께와 균형에 미치는 영향 (The Effect of Trunk Strengthening Exercise using Oscillation on Trunk Muscle Thickness and Balance)

  • 조운수;박치복;임재헌
    • 대한물리의학회지
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    • 제12권2호
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    • pp.91-101
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    • 2017
  • PURPOSE: The aim of this study was to verify the effect of trunk strengthening exercise using oscillation by comparing trunk muscle thickness, as well as balance of healthy adults during exercises performed with an oscillatory device and non-oscillatory device. METHODS: Twenty-two participants were randomly assigned to one of two groups: the trunk strengthening exercise using oscillation (TSEO) group (n=11) or the trunk strengthening exercise using non-oscillation (TSEN) group (n=11). Subjects in all groups performed the exercises three days per week for 6 weeks. All subjects performed four types of exercises: pull over, seated twist, power push, and diagonal power plank. Trunk muscle thickness of the rectus abdominis (RA), internal oblique (IO), external oblique (EO), transverse abdominis (TrA), and multifidus (MT) were measured with an ultrasonography. The balance ability were evaluated using the Romberg test with eyes open, eyes closed, one-leg standing test (OLST), and limits of stability (LOS). All tests were performed before the intervention, as well as after 6 weeks and 8 weeks of exercises. RESULTS: There was a significant difference of RA, IO, TrA, and MT according to the main effect of the time (p<.05). There was a significant difference of IO and LOS according to interaction effect between the time and group (p<.05). CONCLUSION: As intended, the cyclic forces induced by the oscillating device did increase trunk muscle thickness. However, the effect was limited and significant only for the IO muscle. Combining trunk strengthening exercise with oscillation appears to be more effective in improving dynamic balance.

Physical and Mechanical Properties of Wood Fiber-Polypropylene Fiber Composite Panel

  • Kim, Jee-Woong;Eom, Young-Geun
    • Journal of the Korean Wood Science and Technology
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    • 제29권3호
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    • pp.36-46
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    • 2001
  • This study was to find a way of reusing wood and plastic wastes, which considered as a troublesome problem to be solved in this age of mass production and consumption, in manufacturing wood fiber-polypropylene fiber composite panel. And the feasibility of this composite panel as a substitute for existing headliner base panel of automobile was also discussed, especially based on physical and mechanical performance. Nonwoven web composite panels were made from wood fiber and polypropylene fiber formulations of 50 : 50, 60 : 40, and 70 : 30, based on oven-dry weight, with densities of 0.4, 0.5, 0.6, and 0.7 g/$cm^3$. At the same density levels, control fiberboards were also manufactured for performance comparison with the composite panels. Their physical and mechanical properties were tested according to ASTM D 1037-93. To elucidate thickness swelling mechanism of composite panel through the observation of morphological change of internal structures, the specimens before and after thickness swelling test by 24-hour immersion in water were used in scanning electron microscopy. Test results in this study showed that nonwoven web composite panel from wood fibers and polypropylene fibers had superior physical and mechanical properties to control fiberboard. In the physical properties of composite panel, dimensional stability improved as the content of polypropylene fiber increased, and the formulation of wood fiber and polypropylene fiber was considered to be a significant factor in the physical properties. Water absorption decreased but thickness swelling slightly increased with the increase of panel density. In the mechanical properties of composite panel, the bending modulus of rupture (MOR) and modulus of elasticity (MOE) appeared to improve with the increase of panel density under all the tested conditions of dry, heated, and wet. The formulation of wood fiber and polypropylene fiber was considered not to be a significant factor in the mechanical properties. All the bending MOR values under the dry, heated, and wet conditions met the requirements in the existing headliner base panel of resin felt.

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A Chemically-driven Top-down Approach for the Formation of High Quality GaN Nanostructure with a Sharp Tip

  • 김제형;오충석;고영호;고석민;조용훈
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.48-48
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    • 2011
  • We have developed a chemically-driven top-down approach using vapor phase HCl to form various GaN nanostructures and successfully demonstrated dislocation-free and strain-relaxed GaN nanostructures without etching damage formed by a selective dissociation method. Our approach overcomes many limitations encountered in previous approaches. There is no need to make a pattern, complicated process, and expensive equipment, but it produces a high-quality nanostructure over a large area at low cost. As far as we know, this is the first time that various types of high-quality GaN nanostructures, such as dot, cone, and rod, could be formed by a chemical method without the use of a mask or pattern, especially on the Ga-polar GaN. It is well known that the Ga-polar GaN is difficult to etch by the common chemical wet etching method because of the chemical stability of GaN. Our chemically driven GaN nanostructures show excellent structure and optical properties. The formed nanostructure had various facets depending on the etching conditions and showed a high crystal quality due to the removal of defects, such as dislocations. These structure properties derived excellent optical performance of the GaN nanostructure. The GaN nanostructure had increased internal and external quantum efficiency due to increased light extraction, reduced strain, and improved crystal quality. The chemically driven GaN nanostructure shows promise in applications such as efficient light-emitting diodes, field emitters, and sensors.

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