• Title/Summary/Keyword: internal stability

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

  • Kim, Young-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.10
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    • pp.6779-6787
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    • 2015
  • The objective of this study is understand the influence of the teaching ethics of preservice childcare teachers on teacher efficacy and professionalism awareness. In order to achieve the study objective, the questionnaires were distributed to 285 preservice childcare teachers in A city. In the results of the study, first, regarding the teaching ethics perceived by preservice childcare teachers, 'the ethics of infants' were the most highly perceived while the 'teaching strategy' on teacher efficacy, and 'social service' and 'professional ethics' on professionalism awareness were the most highly perceived. Second, preservice childcare teachers' teaching ethics, teacher efficacy, and professionalism awareness had statistically significant correlations. Third, preservice childcare teachers' teaching ethics had positive influence on teacher efficacy and professionalism awareness. Based on the results of this study, in order to improve the quality of the childcare service after understanding the importance of preservice childcare teachers' teaching ethics, it would be necessary to have various researches on the internal stability of the systematic education for childcare teachers to have teacher efficacy and professionalism awareness.

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

  • Na, Ra-Byeol;Kim, Byung-Hyun;Lee, Ju-Seung;Kim, Byeong-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.62-68
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    • 2018
  • This study was conducted to improve the shooting stability of self propelled artillery by improving the flick rammer system. The flick rammer system is designed to reduce crew fatigue and shorten the movement and loading time of the shell compared with the conventional manual loading system. Basically, in the flick rammer system of the shooting type, fall-back occurs intermittently, which causes problems in the rapid loading. To solve this problem, a detailed C.A.E. (Computer Aided Engineering) analysis of the internal structure of the existing rapid loading field was conducted. Through this, we sought a solution that can prevent fall-back by reducing the flying distance. We then optimized the loading station to reduce the flying distance and confirmed the possibility of suppressing the fall-back compared to the existing product through actual tests in the field.

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

  • Kim, Hye-Ryung;Son, Eun-Joo;Kim, Mi-Kyung;Lyu, Eun-Soon
    • Korean Journal of Community Nutrition
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    • v.16 no.4
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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.

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

  • Min, Kyung-Cheon;Hong, Wan-Soo
    • Korean Journal of Community Nutrition
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    • v.23 no.1
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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
    • Journal of the Korea Furniture Society
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    • v.21 no.3
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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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Analysis of Springback and Die Material Suitability in the UHSS Sheet Forming Process (초고강도 강판 성형 시의 스프링백 해석 및 금형 소재 적합성 검토)

  • Oh, I.S.;Yun, D.Y.;Cho, J.H.;Lee, M.G.;Kim, H.Y.;Kim, H.J.
    • Transactions of Materials Processing
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    • v.29 no.4
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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.

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

  • Hong, S.W.;Lee, I.B.;Hong, H.K.;Seo, I.H.;Hwang, H.S.;Bitog, J.P.;Yoo, J.I.;Kwon, K.S.;Ha, T.H.;Kim, K.S.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.50 no.1
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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.

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

  • Cho, Woon-Su;Park, Chi-Bok;Lim, Jae-Heon
    • Journal of the Korean Society of Physical Medicine
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    • v.12 no.2
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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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    • v.29 no.3
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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

  • Kim, Je-Hyeong;O, Chung-Seok;Go, Yeong-Ho;Go, Seok-Min;Jo, Yong-Hun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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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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