• Title/Summary/Keyword: group efficiency

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A study of effects on environment from road deicings (제설제가 환경에 미치는 영향 연구)

  • 신진호;허항록;신정식;김민영;신재영
    • Journal of environmental and Sanitary engineering
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    • v.16 no.4
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    • pp.31-37
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    • 2001
  • Deicers have used for melting snow on the road during winter season, but they have largely influenced on environment and public assets and human health. The pollution level of snow and soil contained deicer was analyzed and evaluated the characteristics of deicers. The results were as follows 1. In the result of measurement of pollutants in snow contained deicer, the pH was a little higher than a comparative group and the concentration of $Cl^{-}$ ranged from 0.5% to 0.87%, and the electric conductivity ranged 12.4 to 24.6 mmho/cm. The concentration of Cd, As, and Hg was not detected, but those of Cu, Pb, Cr was higher than a comparative group. 2. In soil of the road spreaded with deicer, the pH is getting alkalized and the concentration of $Cl^{-}$ was high in January and returned the level of a comparative grout) in November by physical and chemical reaction with deicer, but the concentration of heavy metals were not connected with deicers. 3. In comparison of deicing efficiency, the concentration of $Cl^{-}$ was 3.3~5times high in spreading with deicer before snowing than after snowing. The concentration of $Cl^{-}$ in NaCl was higher than $CaCl_2$, but the deicing efficiency of Nacl was better than that of $CaCl_2$. Moreover, the new deicer have no salt, but deicing efficiency of new deicer was less than that of NaCl and $CaCl_2$.

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A study on the influence of supply chain management efficiency on the training supporting project in small and medium-sized enterprises (중소기업 인적자원개발 지원사업에 대한 공급망경영 유효성에 관한 연구)

  • Seo, Yohan;Kim, Kwang Yong;Sung, Jong Su
    • Journal of Korean Society for Quality Management
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    • v.42 no.3
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    • pp.407-424
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    • 2014
  • Purpose: The purpose of this study was to propose supply chain management efficiency by analyzing moderating effect on the training support project in small and midium-sized enterprise. Methods: The collected data through the survey were analyzed using multi?regression analysis. The measurement tools used for this study were divided into three dimensions such as personal characteristics, supportive environment and training effect. Results: The results of this study are as follows; first, it was found that the effects of personal characteristics and supportive environment were significant on training effect. Second, significant differences were found between supply chain management active group and inactive group. Third, moderating effect of supply chain manage efficiency was found between variables. Conclusion: SME supporting project in training program needs supply chain management efficiency for training effect. Supply chain management needs to be promoted in SMEs not only for performance but also for their workplace learning and learning culture.

Surface Analysis and Conversion Efficiency of Multi-crystalline Silicon Solar Cell by Wet Chemical Etching (습식 화학 식각에 의한 다결정 실리콘 웨이퍼의 표면 분석 및 효율 변화)

  • Park, Seok-Gi;Do, Kyeom-Seon;Song, Hee-Eun;Kang, Gi-Hwan;Ahn, Hyung-Keun;Han, Deuk-Young
    • 한국태양에너지학회:학술대회논문집
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    • 2011.04a
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    • pp.111-115
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    • 2011
  • Surface Texturing is an essential process for high efficiency in multi-crystalline silicon solar cell. In order to reduce the reflectivity, there are two major methods; proper surface texturing and anti-reflection coating. For texturization, wet chemical etching is a typical method for multi-crystalline silicon. The chemical solution for wet etching consists of HF, $NHO_3$, DI and $CH_3COOH$. We carried out texturization by the change of etching time like 15sec, 30sec, 45sec, 60sec and measured the reflectivity of textured wafers. As making the silicon solar cells, we obtained the conversion efficiency and relationship between texturing condition and solar cell characteristics. The reflectivity from 300nm to 1200nm was the lowest with 15 sec texturing time and 60 sec texturing time showed almost same reflectivity as bare one. The 45 sec texturing time showed the highest conversion efficiency.

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Study on the Removal Efficiency of Nitrogen and Phosphorus in Wastewater Treatment System Using Magnetite Powder (자철광 분말을 이용한 하수처리시스템의 질소, 인 제거효율에 관한 연구)

  • Jo, Eun-Young;Park, Seung-Min;Yeo, In-Seol;Moon, Joeng-Sik;Park, Ju-Young;Kim, Jong-Cheol;Kim, Yang-Seob;Park, Chan-Gyu
    • The KSFM Journal of Fluid Machinery
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    • v.18 no.2
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    • pp.43-47
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    • 2015
  • As water quality regulations have tightened, many studies to improve wastewater treatment efficiency have been performed. In this study, magnetite powder was used to maintain a high concentration of MLSS in lab-scale wastewater treatment system. After magnetite powder injection, MLSS concentration was above 8,000 mg/L and it was 3.2 times higher than control group(2,500 mg/L). In addition, nitrogen removal efficiency and phosphorus removal efficiency comparing with the control group was increased 20.5% and 11%, respectively.

A SCANNING ELECTRON MICROSCOPIC STUDY ON THE REMOVING EFFICIENCY OF SMEAR LAYER BY K-FILE AND ULTRASONIC INSTRUMENT (K-FILE과 초음파 기구의 도말층제거효과에 대한 주사전자 현미경적 연구)

  • Lee, Su-Jong;Im, Mi-Kyung
    • Restorative Dentistry and Endodontics
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    • v.19 no.1
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    • pp.97-105
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    • 1994
  • The purpose of this study was to evaluate the smear layer removing efficiency of two root canal preparation techniques. Twelve single-rooted teeth were used in two groups of six each. Group 1 was biomechanically prepared by hand using a K-file with a high volume of normal saline irrigation. Group 2 was. prepared by using ultrasonically activated K-file with a constant high volume of normal saline irrigation. After the experimental procedures, each root was split saggitally. The removing efficiency of the preparation methods were assessed in terms of surface condition of the canal walls at three levels, those coronal, middle, and apical thirds. On the basis of remaining debris, presence of smear layer, and patency of dentinal tubules, each canal was evaluated according to a scale form 0 to 2. A statistical analysis was used to indicated any significant differences in surface condition between the two methods. There was no statistical significance between hand instrumentation and ultrasonic instrumentation at the cervical third but removing efficiency of ultrasonic instrumentation was superior. No statistically significant differences were obhserved for middle or apical third.

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EFFECTS OF DIETARY THYROXINE ON GROWTH PERFORMANCE AND CARCASS QUALITY OF BROILERS FED DIFFERENT LEVELS OF DIETARY PROTEIN

  • Kim, J.W.;Lee, C.H.;Han, I.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.6 no.4
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    • pp.527-539
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    • 1993
  • To investigate the effects of crude protein and thyroxine on growth performance, nutrient utilizability, carcass composition, the content of total fat and cholesterol in leg muscle, breast muscle and liver, and caloric efficiency in broiler chicks. The experiment involved 3 levels of dietary crude protein (1-3 weeks: 20, 23, 26%; 4-6 weeks: 17, 20, 23%) and 3 levels of thyroxine (0.0, 1.5, 3.0 mg/kg). In the starting period (1-3 weeks), body weight gain of chicks fed diets containing 26% crude protein and 1.5 mg/kg thyroxine was higher than any other groups, and among thyroxine levels, 3.0 mg/kg thyroxine groups were lower. The best feed efficiency was obtained at 26% crude protein with no thyroxine supplemented or 1.5 mg/kg thyroxine supplemented groups. In the finishing period (4-6 weeks) the highest body weight gain was obtained at 23% crude protein with no thyroxine supplemented group. Feed intake of 17% crude protein with 1.5 mg/kg thyroxine supplemented group was higher than those of the other groups. It was found that the utilizability of crude protein in the starting period, showed the best utilizability at 20% crude protein with 1.5 mg/kg thyroxine group. Increasing crude protein level from 17 to 23%, utilizability of crude fat was decreased. The carcass composition was significantly (p<0.05) influenced by crude protein and thyroxine. Increasing thyroxine level from 0.0 to 3.0 mg/kg, crude protein content was increased whereas, crude fat content was decreased. Chicks fed diet containing 1.5 mg/kg thyroxine showed the lowest total fat content in liver tissue. In breast muscle, it was significantly (p<0.05) affected by crude protein and thyroxine. Present data revealed that the cholesterol content was increased for the chicks fed 3.0 mg/kg thyroxine. It the caloric efficiency, chicks fed a diet containing 20% crude protein with no thyroxine supplementation showed the highest caloric efficiency and the lowest efficiency was from 23% crude protein group with 1.5 mg/kg thyroxine. From this study it may be concluded that crude fat content of carcass could be successfully reduced by dietary supplementation of thyroxine, whereas crude protein content was increased.

The Effects of Experience of Studying Mathematics Education for Young Children Based on Picture Books on Pre-service Early Childhood Teachers with Their Attitude Toward Mathematics and Mathematics Teaching Efficiency (그림책을 활용한 유아수학교육 학습 경험이 예비 유아교사의 수학에 대한 태도와 수학교수효능감에 미치는 영향)

  • Lee, Seon Kyung
    • Korean Journal of Child Education & Care
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    • v.19 no.2
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    • pp.19-33
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    • 2019
  • Objective: The purpose of this study is to understand how the experience of studying mathematics education for young children based on picture books is affecting pre-service early childhood teachers with their attitude toward mathematics and mathematics teaching efficiency. Methods: For this, a total of 39 pre-service early childhood teachers majoring in early childhood education at S university located in G metropolitan city participated in the study. 20 of them are randomly assigned to the experimental group while the rest 19 were assigned to the control group. The experimental group participated in the classes of mathematics education for young children based on picture books for 15 weeks, while the control group attended the normal classes of mathematics education for young children for the same period of time. By using SPSS 18.0 Program for the collected data, t-test was conducted for differences in the results of attitude toward mathematics and mathematics teaching efficiency. Results: The results of this study are as follows. Firstly, the experience of studying mathematics education for young children based on picture books had a positive effects on pre-service early childhood teachers' attitude toward mathematics, improved values and interest in mathematics, and reduced anxiety about mathematics. Secondly, the experience of studying mathematics education for young children based on picture books had a positive effects on improving pre-service early childhood teachers' mathematics teaching efficiency. Also, both faith in ability and faith in results have improved significantly. Conclusion/Implications: These results imply that the experience of studying mathematics education for young children based on picture books is an effective teaching-learning method in improving pre-service early childhood teachers' attitude toward mathematics and mathematics teaching efficiency.

Analysis of Research and Development Efficiency of Artificial Intelligence Hardware of Global Companies using Patent Data and Financial data (특허 데이터 및 재무 데이터를 활용한 글로벌 기업의 인공지능 하드웨어 연구개발 효율성 분석)

  • Park, Ji Min;Lee, Bong Gyou
    • Journal of Korea Multimedia Society
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    • v.23 no.2
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    • pp.317-327
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    • 2020
  • R&D(Research and Development) efficiency analysis is a very important issue in academia and industry. Although many studies have been conducted to analyze R&D(Research and Development) efficiency since the past, studies that analyzed R&D(Research and Development) efficiency considering both patentability and patent quality efficiency according to the financial performance of a company do not seem to have been actively conducted. In this study, measuring the patent application and patent quality efficiency according to financial performance, patent quality efficiency according to patent application were applied to corporate groups related to artificial intelligence hardware technology defined as GPU(Graphics Processing Unit), FPGA(Field Programmable Gate Array), ASIC(Application Specific Integrated Circuit) and Neuromorphic. We analyze the efficiency empirically and use Data Envelopment Analysis as a measure of efficiency. This study examines which companies group has high R&D(Research and Development) efficiency about artificial intelligence hardware technology.

A study of the Body Growth and Development in Albino Rats Fed by the Cereals and Legumes Proteins (곡류 및 두류 단백질이 흰쥐의 성장 발육에 미치는 영향)

  • Lee, Jong-Mee
    • Journal of Nutrition and Health
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    • v.10 no.1
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    • pp.10-17
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    • 1977
  • This study was designed to compare the Biological effects of the cereals and legumes Proteins on albino rats. Fifty weaning albino rats weighing $49\;gr{\pm}2$ in both sexes were divided into 5 groups and fed corn crude protein diet, wheat crude protein diet, soybean protein diet, yeast diet and 30% sugar-casein diet for the control group. The protein contains same levels with isocaloric values each diet. After 12 weeks the rats were sacrificed for chemical analysis and the results are as follow ; 1. The highest food consumption was found in the groups of yeast and soybean, and the lowest was found in the groups of wheat diet and corn diet. 2. The groups of yeast & soybean protein showed the highest body weight increase, while the groups of wheat diet and corn diet showed the lowest. 3. Highly significant difference was found between the standard group and the groups of corn protein and soybean protein in Food Efficiency Ratio. (F. E. R.) (p<0.01). 4. Protein Efficiency Ratio showed a similar pattern as the F.E.R., however, there was no significant differences among the groups. 5. The kind of diets did not influence the hematology of the subjects. 6. The rate of nitrogen retention of male standard group was lower compared with all the experimental groups (p<0.01), and that of female soybean group was higher than any other groups (p<0.01). 7. Female corn diet group had the lowest organ weights, as found in the growth rate, which was significant (p<0.01). In the male corn diet group only the kidney showed significantly low in weight (p<0.01), and the spleen of male yeast group was also shown low with significance (p<0.01). 8. Nitrogen retentions of the liver and muscle in male corn diet group were lower than any other groups (p<0.05), and the brain nitrogen content of female standard group was high with significance (p<0.01). According to the results above, yeast and soybean protein can be regarded as a nutritious and also inexpensive protein sources.

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Influence of Dietary Protein Source and Level on Lead Accumulation in Rat (단백질 급원과 수준을 달리한 식이가 흰쥐의 납축적에 미치는 영향)

  • 김옥경
    • Journal of Nutrition and Health
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    • v.19 no.3
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    • pp.211-223
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    • 1986
  • In this experiment forty-eight Sprague Dawley male rats were chosen and used in order to measure the growth rates and to see the effects of lead acumulation in their organs resulting from variously controlled lead protein diet. Protein sources were casein and isolated soyprotein (ISP), and each source was divided into three groups : 7% low protein [LP], 20% standard protein (SP) and 40% high protein (HP) groups. The six experimental groups were given lead acetate(25 mg/kg B.W.) and six control groups were given sodium chloride by oral administration 6 times a week for weeks. The results from this experiment were summeraized as following ; 1) Food consumption, weight gain, organ weight and food efficiency ; Lead acetate administration with protein source had no effects on food consumption, weight gain and organ weight . By their different levels of protein, food consumption of LP group was less the that of SP and HP groups after 3 weeks, weight gain of LP group was less than that of SP and HO groups after 1 weeks. The organ weight in LP group was significantly lower than SP and HP groups except teeth and adrenal s. Effect of lead acetate administration on food efficiency have significantly lower in LP-ISP diet and HP -casein diet than other groups only first week. By their different levels LP group showed significantly lower than SP group until 3 weeks. 2) Hematopoietic effect ; The hematopoieteic effect was not influencec by lead acdtate administration and protein source. But the LP group showed a significantly lowe hematopoietic effect than the SP, HP, groups. 3) Accumulation of lead in the liver, kidney, teeth by protein source showed no significantly differences. Accumulation of lead in blood, heart of LP group, spleen of LP and HP groups. femur of SP and HP groups fed with casein diet groups were significantly higher than fed with ISP diet groups. By their different levels of group showed generally higher than SP and HP groups. But accumulation of lead in teeth of HP group was high also.