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A Study on the Water Relation Characteristics of the Soybean Shoots through the Pressure Chamber Technique (Pressure Chamber Technique에 의한 대두경엽의 수분특성 연구)

  • E-Hun Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.28 no.1
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    • pp.128-132
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    • 1983
  • The water relations parameters such as original osmotic pressure $(\Pi_0)$, osmotic pressure $(\Pi_p)$, at the incipient plasmolysis, the volume of osmotic water $(V_o)$ at the full turgor, the relative water content $(RWC^*)$ at the incipient plasmolysis, the volume of osmotic water$(V_p)$ at the incipient plasmolysis, the volume of symplasmic and apoplastic water$(w_s)$ at the maximum turgor, $V_pV_o, \; V_oW_s, \; W_sD_w, \; V_oF_w$ and the elastic modulus were measured through the pressure chamber (DIK-PC-40 Model) technique with the Williams and Geumgangdaerip soybean cultivar shoots. The original osmotic pressure$(\P $i_{0}$ )$, of the both cultivars shoots were appeared insignificant differences as 8.1 bar and 7.8 bar respectively. The osmotic pressure($\pi$$_{p}$ ) at the incipient plasmolysis was 9.0 bar in Williams and 10.4 bar in Geumgangdaerip. The relative water content(RW $C^{*}$) at the incipient plasmolysis was 86.0 per cent in Geumgangdaerip and 92.6 per cent in Williams. The ratio of volume of osmotic water( $V_{p}$ ) at the incipient plasmolysis to total symplasmic water$(V_o)$ , i.e., $V_p/V_o$ was 83.4 per cent in Geumgangdaerip and 90.4 per cent in Williams. The elastic modulus of Geumgangdaerip shoots showed higher value than Williams$(8.5 $\times$ 10^2bar)$ as $1.6 \times10^5$ bar.r.

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Reliability Assessment Based on an Improved Response Surface Method (개선된 응답면기법에 의한 신뢰성 평가)

  • Cho, Tae Jun;Kim, Lee Hyeon;Cho, Hyo Nam
    • Journal of Korean Society of Steel Construction
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    • v.20 no.1
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    • pp.21-31
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    • 2008
  • response surface method (RSM) is widely used to evaluate th e extremely smal probability of ocurence or toanalyze the reliability of very complicated structures. Althoug h Monte-Carlo Simulation (MCS) technique can evaluate any system, the procesing time of MCS dependson the reciprocal num ber of the probability of failure. The stochastic finite element method could solve thislimitation. However, it is limit ed to the specific program, in which the mean and coeficient o f random variables are programed by a perturbation or by a weigh ted integral method. Therefore, it is not aplicable when erequisite programing. In a few number of stage analyses, RSM can construct a regresion model from the response of the c omplicated structural system, thus, saving time and efort significantly. However, the acuracy of RSM depends on the dist ance of the axial points and on the linearity of the limit stat e functions. To improve the convergence in exact solution regardl es of the linearity limit of state functions, an improved adaptive response surface method is developed. The analyzed res ults have ben verified using linear and quadratic forms of response surface functions in two examples. As a result, the be st combination of the improved RSM techniques is determined and programed in a numerical code. The developed linear adapti ve weighted response surface method (LAW-RSM) shows the closest converged reliability indices, compared with quadratic form or non-adaptive or non-weighted RSMs.

Evaluation of synbiotics as gut health improvement agents against Shiga toxin-producing Escherichia coli isolated from the pig

  • Kim, Bo-Ra;Cho, Kyung Jin;Kim, Doowan;Cho, Jin Ho;Lee, Jun Hyung;Guevarra, Robin B.;Lee, Sun Hee;Kang, Jung Sun;Cho, Won Tak;Wattanaphansak, Suphot;Kang, Bit Na;Kim, Jong Nam;Song, Minho;Kim, Hyeun Bum
    • Journal of Animal Science and Technology
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    • v.61 no.2
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    • pp.55-60
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    • 2019
  • Colibacillosis is one of the major health problems in young piglets resulting in poor health and death caused by Escherichia coli producing F18 pili and Shiga toxin 2e. It is pivotal to reduce colibacillosis in weaned piglets to enhance production performance. In this study, we evaluated synbiotics as the gut health improvement agents in the mouse model challenged with Shiga toxin-producing E. coli (STEC) isolated from piglets. Prebiotic lactulose was formulated with each $5.0{\times}10^6CFU/mL$ of Pediococcus acidilactici GB-U15, Lactobacillus plantarum GB-U17, and Lactobacillus plantarum GB 1-3 to produce 3 combinations of synbiotics. A total of 40 three weeks old BALB/c mice were randomly assigned to 4 groups (n = 10): a control group and 3 synbiotics treated groups. Each treatment groups were daily administrated with $5.0{\times}10^6CFU/mL$ of one synbiotics for the first week, and every 3 days during the second week. All the mice were challenged with $8.0{\times}10^8CFU/mL$ of STEC 5 days after animals began to receive synbiotics. Mice treated with synbiotics based on Pediococcus acidilactici GB-U15 and Lactobacillus plantarum GB-U17 significantly improved daily weight gain compared to mice in other groups. While mice treated with GB-U15 showed better fecal index, no significant differences were observed among groups. Gross lesion and histopathological evaluations showed that mice treated with GB-U15 moderately improved recovery from STEC infection. In conclusion, our results suggest that the synbiotics formulated with lactulose and Pediococcus acidilactici GB-U15 have potential benefits to prevent and improve colibacillosis in weaned piglets.

Position of Hungarian Merino among other Merinos, within-breed genetic similarity network and markers associated with daily weight gain

  • Attila, Zsolnai;Istvan, Egerszegi;Laszlo, Rozsa;David, Mezoszentgyorgyi;Istvan, Anton
    • Animal Bioscience
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    • v.36 no.1
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    • pp.10-18
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    • 2023
  • Objective: In this study, we aimed to position the Hungarian Merino among other Merinoderived sheep breeds, explore the characteristics of our sampled animals' genetic similarity network within the breed, and highlight single nucleotide polymorphisms (SNPs) associated with daily weight-gain. Methods: Hungarian Merino (n = 138) was genotyped on Ovine SNP50 Bead Chip (Illumina, San Diego, CA, USA) and positioned among 30 Merino and Merino-derived breeds (n = 555). Population characteristics were obtained via PLINK, SVS, Admixture, and Treemix software, within-breed network was analysed with python networkx 2.3 library. Daily weight gain of Hungarian Merino was standardised to 60 days and was collected from the database of the Association of Hungarian Sheep and Goat Breeders. For the identification of loci associated with daily weight gain, a multi-locus mixed-model was used. Results: Supporting the breed's written history, the closest breeds to Hungarian Merino were Estremadura and Rambouillet (pairwise FST values are 0.035 and 0.036, respectively). Among Hungarian Merino, a highly centralised connectedness has been revealed by network analysis of pairwise values of identity-by-state, where the animal in the central node had a betweenness centrality value equal to 0.936. Probing of daily weight gain against the SNP data of Hungarian Merinos revealed five associated loci. Two of them, OAR8_17854216.1 and s42441.1 on chromosome 8 and 9 (-log10P>22, false discovery rate<5.5e-20) and one locus on chromosome 20, s28948.1 (-log10P = 13.46, false discovery rate = 4.1e-11), were close to the markers reported in other breeds concerning daily weight gain, six-month weight, and post-weaning gain. Conclusion: The position of Hungarian Merino among other Merino breeds has been determined. We have described the similarity network of the individuals to be applied in breeding practices and highlighted several markers useful for elevating the daily weight gain of Hungarian Merino.

A Hybrid Forecasting Framework based on Case-based Reasoning and Artificial Neural Network (사례기반 추론기법과 인공신경망을 이용한 서비스 수요예측 프레임워크)

  • Hwang, Yousub
    • Journal of Intelligence and Information Systems
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    • v.18 no.4
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    • pp.43-57
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    • 2012
  • To enhance the competitive advantage in a constantly changing business environment, an enterprise management must make the right decision in many business activities based on both internal and external information. Thus, providing accurate information plays a prominent role in management's decision making. Intuitively, historical data can provide a feasible estimate through the forecasting models. Therefore, if the service department can estimate the service quantity for the next period, the service department can then effectively control the inventory of service related resources such as human, parts, and other facilities. In addition, the production department can make load map for improving its product quality. Therefore, obtaining an accurate service forecast most likely appears to be critical to manufacturing companies. Numerous investigations addressing this problem have generally employed statistical methods, such as regression or autoregressive and moving average simulation. However, these methods are only efficient for data with are seasonal or cyclical. If the data are influenced by the special characteristics of product, they are not feasible. In our research, we propose a forecasting framework that predicts service demand of manufacturing organization by combining Case-based reasoning (CBR) and leveraging an unsupervised artificial neural network based clustering analysis (i.e., Self-Organizing Maps; SOM). We believe that this is one of the first attempts at applying unsupervised artificial neural network-based machine-learning techniques in the service forecasting domain. Our proposed approach has several appealing features : (1) We applied CBR and SOM in a new forecasting domain such as service demand forecasting. (2) We proposed our combined approach between CBR and SOM in order to overcome limitations of traditional statistical forecasting methods and We have developed a service forecasting tool based on the proposed approach using an unsupervised artificial neural network and Case-based reasoning. In this research, we conducted an empirical study on a real digital TV manufacturer (i.e., Company A). In addition, we have empirically evaluated the proposed approach and tool using real sales and service related data from digital TV manufacturer. In our empirical experiments, we intend to explore the performance of our proposed service forecasting framework when compared to the performances predicted by other two service forecasting methods; one is traditional CBR based forecasting model and the other is the existing service forecasting model used by Company A. We ran each service forecasting 144 times; each time, input data were randomly sampled for each service forecasting framework. To evaluate accuracy of forecasting results, we used Mean Absolute Percentage Error (MAPE) as primary performance measure in our experiments. We conducted one-way ANOVA test with the 144 measurements of MAPE for three different service forecasting approaches. For example, the F-ratio of MAPE for three different service forecasting approaches is 67.25 and the p-value is 0.000. This means that the difference between the MAPE of the three different service forecasting approaches is significant at the level of 0.000. Since there is a significant difference among the different service forecasting approaches, we conducted Tukey's HSD post hoc test to determine exactly which means of MAPE are significantly different from which other ones. In terms of MAPE, Tukey's HSD post hoc test grouped the three different service forecasting approaches into three different subsets in the following order: our proposed approach > traditional CBR-based service forecasting approach > the existing forecasting approach used by Company A. Consequently, our empirical experiments show that our proposed approach outperformed the traditional CBR based forecasting model and the existing service forecasting model used by Company A. The rest of this paper is organized as follows. Section 2 provides some research background information such as summary of CBR and SOM. Section 3 presents a hybrid service forecasting framework based on Case-based Reasoning and Self-Organizing Maps, while the empirical evaluation results are summarized in Section 4. Conclusion and future research directions are finally discussed in Section 5.

A Study on Balanced -type Oseillating Mole-Drainer(III)-Model Test for Draft Force, Torque, Power and Moment (평행식 진동탄환 암거 천공기의 연구(III)-견인력, 토크, 동력 및 모멘크에 관한 모형시험-)

  • 김용환
    • Journal of Biosystems Engineering
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    • v.1 no.1
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    • pp.1-6
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    • 1976
  • This paper is the third one of the study on balanced type oscillating mole-drainer, the first one was presented in No 9. Gyeongsang College Report and the second one in Vol. 17, No.4 of the KSAE. In the first part of this study, the characteristics of traction forces between the nonoscillating earth working equipments and oscillating ones was compared. A model of the balanced type oscillating mole-drainer, which composed of a mechanism that may reduce the machine vibration, was designed following the dimensional analysis and similitude technique. The model test was carried out to clarify the balancing mechanism of the oscillating parts and other parts of the machine. In the light of the results from the model tests, a prototype machine was made for experimental purpose. Results from the field test by a reported in the near future. In the second report, the model tests were carried out under the same soil conditions, i.e, . oscillating frequency, running velocity, and oscillating amplitude, etc. It was clear that use of balanced type oscillating model could substantially reduce the vibration of the whole system of the machine, when compared with the nonoscillating type model. In this paper(the third report), results of investigation on the traction force, power requirement, and moment. etc, is presented. Analysis of variance technique was used for analyzing the effect of the frequency, amplitude, and running velocity on the draft force, torque, power requirements, and moments. The results obtained from the model tests are as follows, 1) By practicing a balanced-type oscillating mole-drainer, it was possible to reduce the traction resistance by 55.1-61. 2 percent of traction resistance, however, was 1.75 - 1.95 times greater than the value of resistance which was induced by use of a mole-drainer with single bullet. The resistance of rear shank against soil was considered as a main causing factor of the above results. 2) As the oscillation frequency was increased, the traction resistance was decreased. Considering on the effect of oscillation the greater the amplitude, and the slower the running velocity was, the greater the reduction ratio of traction resistance was. 3) The ratio of the traction resistance of oscillating mole-drainer to that of non-oscillating one could be represented as a function of dimensionless variable (V/$Af$). The results from the tests were well agreed with the reported results from the experim ents on oscillation plow or hoe. 4) By taking a lower value of (V/$Af$), reducing the traction resistance was possible. This fact meant, however, that the efficiency of mole drain practice would be lower. 5) It was experimentally confirmed under the same condition of soil that the variable (R/$rD1^3$) could be represented as a function of a variable($V^2/gD$) when a non\ulcornerocillating mole-drainer was used. 6) When a oscillating mole-drainer was used, the variable(R/$rD_1^{3}$) could be represented as a function of two variables ($v^2/gD_1$) and (V^2/gD_1$). 7) The torque was not affected by a change of frequency. However, a relation of proportionality existed between torque and amplitude, running velocity, and ratio of bullet diameter. When a balanced type oscillating mole-drainer with two bullets was used, torque was increased by 52.8-78. 4 percent and total power requirement was also increased. 8) Total power requirement was increased linearly in accordance with the increasing frequency, 41.96 percent of total power was used for oscillating action. The magnitude of total power requirement was 1. 8-9. 4 times greater than that of a non-oscillating mechanism. In the view point of power requirement, it was not advisable to increase the frequency, amplitude, running velocity, and ratio of bullet diameter at the same time. 9) Only the positive moment occured in the rear shank. Change of the diameter of a rear bullet, could not affect the balancing against the soil resistance. It was necessary for rear bullet to have a large resistance against soil only when the rear bullet was in backward motion. 10) Within an extent of the experimental base, optimum limits for several design factors were A=0.5cm, $f$=22.5Hz, V=O. 05m/sec, and $\lambda$=1.0 By adapting these values traction resistance was reduced by 40 percent and vibration acceleration wa s reduced by 60 percent. Even though the total , power requirements for operating a balanced type oscillation mechanism was greater ~than that of non-oscillating one, using a oscillating mechanism would be more effective. Because a balanced type oscillating mechanism is used, tractive resistance will be reduced and then the lighter . tractive equipment could be used.

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Microbiological Hazard Analysis for Strawberry Farms at the Harvest Stage to Establish Good Agricultural Practices (GAP) Model Based on Principle of HACCP (HACCP 원리에 기초하는 GAP모델 확립을 위한 딸기 농장의 수확단계에 대한 미생물학적 위해요소 조사)

  • Shim, Won-Bo;Kim, Kyeong-Yeol;Yoon, Yo-Han;Kim, Jang-Eok;Shim, Sang-In;Kim, Yun-Shik;Chung, Duck-Hwa
    • Korean Journal of Food Science and Technology
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    • v.45 no.1
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    • pp.104-110
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    • 2013
  • This study assessed hazards at the harvest stage of strawberry farms which may cause risk to humans. A total of 216 samples were collected from 6 strawberry farms (soil culture farms: A, B, C; nutriculture farms: D, E, F) located in Western Gyeongnam. The collected samples were subjected for sanitary indicator bacteria (aerobic plate count, coliforms and Escherichia coli), major foodborne pathogens (E. coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus and Bacillus cereus), and fungi. The levels of APC and coliform in the soil culture farms were 1.0-6.9 and 0.4-4.6 log CFU/g (leaf, mL, hand or 100 $cm^2$), respectively. The samples obtained from the nutriculture farms were contaminated with the levels of 0.8-4.9, and 0.2-2.6 log CFU/g (leaf, mL, hand or 100 $cm^2$) of APC and coliform. However, E. coli was not detected in any samples. In major foodborne pathogens, S. aureus was detected at the level of ${\leq}$3.3 log CFU/hand in workers' hand samples and B. cereus was detected at the levels of 0.4-4.1 log CFU/g (hand or 100 $cm^2$) in soil, plants and workers' hygiene. L. monocytogenes, E. coli O157:H7 and Salmonella spp. were not detected. Fungi were detected at the levels of 1.0-5.2 and 0.2-4.4 log CFU/g (leaf, mL, hand or 100 $cm^2$) in soil culture and nutriculture farms, respectively.

Evaluation of Impact Factor in Composite Cable-Stayed Bridges under Reliability-based Live Load Model (신뢰도 기반 활하중모델에 의한 강합성 사장교의 충격계수 평가)

  • Park, Jae Bong;Park, Yong Myung;Kim, Dong Hyun;Lee, Jong Han
    • Journal of Korean Society of Steel Construction
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    • v.25 no.4
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    • pp.335-346
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    • 2013
  • AASHTO LRFD and Korean Bridge Design Code (Limit State Design) specify to consider Truck and Lane load simultaneously determined from reliability-based live load model, and impact shall be applied to the truck load while it shall not be applied to the lane load. In this paper, vehicle-bridge interaction analysis under moving truck and lane loads were performed to estimate impact factor of the cables and girders for the selected multi-cable-stayed composite bridges with 230m, 400m and 540m main span. A 6-d.o.f. vehicle was used for truck load and a series of single-axle vehicles was applied to simulate equivalent lane load. The effect of damping ratio on the impact factor was estimated and then the essential parameters to impact factor, i.e., road surface roughness and vehicle speed were considered. The road surface roughness was randomly generated based on ISO 8608 and it was applied to the truck load only in the vehicle-bridge interaction analysis. The impact factors evaluated from dynamic interaction analysis were also compared with those by the influence line method that is currently used in design practice to estimate impact factor in cable-stayed bridge.

산업안전관리자의 안전의식 연구

  • 권영국
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.196-204
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    • 1997
  • 우리 나라는 한해에 안전사고로 인해 12만 .+-. 2만명정도의 재해자를 발생시키고 있으며, 재해의 천국이라는 오명까지 얻게 되었다. 따라서 본 연구는 우리나라의 산업안전관리자의 안전의식을 분석함으로써 재해발생의 감소에 일조를 하고자 함을 본 연구의 목적으로 한다. 연구기간은 1997년 3월에서 8월까지며, 총 200여명의 강원지역의 산업안전관리자들을 대상 으로 설문조사하여, 그중 불성실하게 답한 것을 제외한 183명의 관리자들의 응답결과를 토 대로 통계분석을 실시하였다. 연구내용은 안전의식에 대한 설문조사를 통하여 그들의 근무 조건과 안전에 대한 지식정도, 현 직장에의 만족과 불만족요인과 자주 쓰는 재해통해방법들을 조사하여 우리나라의 안전관리자들의 현 상황을 유추해 보고자 시도하였다. 분석결과 183명 중 여성은 불과 3명뿐이며, 83%가 기혼이며, 대졸은 전체의 25.1%이며, 59.6%가 고졸이며 , 전문대졸은 15.2%나 되었다. 전담 안전관리자는 전체의 8%에 불과했으며, 대부분 겸임을 하고 있었다. 놀라운 것은 안전관리자들의 92.6%가 안전관리자격증이 없었으며, 2급이 4.7% 에 불과했다. 과거에 부상을 당한 경험이 있는 안전관리자는 전체의 26.3%에 달해 회사가 부상을 당한 근로자를 안전부서로 발령한다는 사실을 확인할 수 있었다. 다친 원인의 50%가 시설물 결함으로 나타나 작업환경개선이 시급함을 알 수가 있었다. 우리나라도 선진국과 같은 교욱담당의 NIOSH와 제재담당의 OSHA와 같은 기관의 설립이 보다 효율적이고 근본적인 안전 관리의 문제해결책이라고 사료된다. 열악한 중소기업에 나라에서 안전교육을 담당해 주는 대신 기업은 근로자들에게 보다 안전한 환경을 제공해야 된다는 것이 이러한 기관설립의 목적이라고 하겠다. 더 나아가 이를 총괄하는 안전관리청의 신설이 보다 근본적인 문제해결을 제공해 줄 수 있을 것으로 사료된다.의 결과는 자전거 에르고노미터의 결과가 트레드밀의 결과에 87.60%정도 나타났다.음을 관찰하였다. 특히 vitamin C와 E의 병용투여는 상승적으로 적용하여 간세포손상을 더욱 억제시킴을 알 수 있었다.mance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI (Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and f[ are significant and positively related to the

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가사활동에 따른 피로도 감소를 위한 입좌식 부엌가구의 개발에 관한 연구

  • 김철홍;최재순;성영애;김태광
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.142-151
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    • 1997
  • 본 연구는 주부들의 주활동공간인 부엌가구와 공간의 설계에 있어사용하기 편리하며 가사활동에 따 른 피로를 경감시키고 요통과 같은 주부직업병을 예방할 수 있는 부엌가구와 공간의 개발에 그 목적을 두었다. 연구는 먼저 수도권의 32평형 규모의 아파트150가구를 대상으로 설문조사를 실시하였으며, 만 24시간동안의 실제 가사활동을 Video로 촬영하여 동작분석을 실시하였다. 그 결과 주부들은 수납의 용 이성과 공간의 크기, 작업대의 높이 등을 가장 많은 개선사항으로 지적하였으며, 절반이상의 주부들이 앉은 자세에서 작업이 이루어졌으면 좋겠다고 응답하였다. 또한 동작분석 결과 작업의 70%이상이 개수 대를 중심으로 조리대와 가열대 주변의 한정된 공간에서정적으로 선 자세에서이루어지는 것으로 파악 되었다. 이러한 선 자세에서의 작업에 따른 피로도를 감소시키기 위하여 입좌식 의자를 도입하였으며, 개수대를 씽크대의 'ㄱ'자 코너에 위치하여 주방활동시의 이동거리를 단축하고자 하였다. 피로도의 경감 을 측정하기 위하여 입좌식 의자를 도입한 개선된 씽크대와 기존의 입식씽크대에서 가사활동시 요구되는 주부들의 에너지 대사량을 비교하기 위하여 심장박동수와 산소호흡량을 측정하였다. 실험결과에 따르면 주방에 입좌식의자를 도입한 경우가 가사활동에 요구되는 에너지 소모량이 심장박동수와 산소호흡량의 기준에서 각각 평균적으로 30%와 57.5% 이상이 감소하는 것으로 파악되어 이러한 부엌가구의 도입으로 주부들의 가사활동에따른 피로도가 절반 가까이 감소될 수 있음을 니타내었다. 또한 부엌가구의 재배치 에따른 가사활동시 이동거리가 평균적으로5.5%이상이 감소하는 것으로 나타났다. 본 연구결과를 주방설 계에 적용할 경우 가사활동의 효율성과 편리성이 향샹됨은 물론 가사활동에따른 피로도를 경감 시키고 요통 등의 주부직업병을 예방할 수 있을 것으로 기대된다.1일 1회씩 4회 투여한 군에서도 암수에 상관없이 전 농도 군에서 염색체이상을 나타내지 않아 유전독성을 나타내지 않음을 관찰하였다. 특히 vitamin C와 E의 병용투여는 상승적으로 적용하여 간세포손상을 더욱 억제시킴을 알 수 있었다.mance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI (Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and f[ are signif

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