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Effects of Working Conditions on Satisfaction with Work Environment and Mediating Effects of Providing Health and Safety Information among Construction Workers (건설업 종사자의 근로조건이 근로환경만족도에 미치는 영향과 안전보건정보제공의 매개효과)

  • Lee, Mi-eun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.30 no.2
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    • pp.213-225
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    • 2020
  • Objectives: In order to prepare measures to enhance construction workers' satisfaction with their working environment, the effects of working conditions and the mediating effects of safety and health information on workers' satisfaction with their working environment in the construction industry have been studied. The results of this study can be used as basic data for further studies in this field. Method: Data on 1,361 male construction workers from the 5th Korea Working Condition Survey (KWCS) were used for this study. The effects of working conditions were analyzed using SPSS 25.0 and the mediating effects of health and safety information were analyzed with SPSS PROCESS macro using the bootstrap method. Results: The safety and health management system and the self-determination of break time had a statistically significant positive effect on satisfaction with the working environment. Chemical and ergonomic risk factors had a statistically significant negative effect on satisfaction with the working environment. The provision of safety and health information, the mediating variable, had a statistically significant positive effect on satisfaction with the working environment. Therefore, it had a mediating effect between working conditions and satisfaction with the working environment. Conclusion: In order to enhance construction workers' satisfaction with their working environment, the above results suggest that the safety and health management system should be well established; self-determination of break times should be guaranteed; and chemical and ergonomic risk factors should be controlled. In addition, workers should be provided with necessary health and safety information related to their work. This study will be useful if these findings are used as basic data in further studies in related fields.

Rancidity Prediction of Soybean Oil by Using Near-Infrared Spectroscopy Techniques

  • Hong, Suk-Ju;Lee, Ah-Yeong;Han, Yun-hyeok;Park, Jongmin;So, Jung Duck;Kim, Ghiseok
    • Journal of Biosystems Engineering
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    • v.43 no.3
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    • pp.219-228
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    • 2018
  • Purpose: This study evaluated the feasibility of a near-infrared spectroscopy technique for the rancidity prediction of soybean oil. Methods: A near-infrared spectroscopy technique was used to evaluate the rancidity of soybean oils which were artificially deteriorated. A soybean oil sample was collected, and the acid values were measured using titrimetric analysis. In addition, the transmission spectra of the samples were obtained for whole test periods. The prediction model for the acid value was constructed by using a partial least-squares regression (PLSR) technique and the appropriate spectrum preprocessing methods. Furthermore, optimal wavelength selection methods such as variable importance in projection (VIP) and bootstrap of beta coefficients were applied to select the most appropriate variables from the preprocessed spectra. Results: There were significantly different increases in the acid values from the sixth days onwards during the 14-day test period. In addition, it was observed that the NIR spectra that exhibited intense absorption at 1,195 nm and 1,410 nm could indicate the degradation of soybean oil. The PLSR model developed using the Savitzky-Golay $2^{nd}$ order derivative method for preprocessing exhibited the highest performance in predicting the acid value of soybean oil samples. onclusions: The study helped establish the feasibility of predicting the rancidity of the soybean oil (using its acid value) by means of a NIR spectroscopy together with optimal variable selection methods successfully. The experimental results suggested that the wavelengths of 1,150 nm and 1,450 nm, which were highly correlated with the largest absorption by the second and first overtone of the C-H, O-H stretch vibrational transition, were caused by the deterioration of soybean oil.

Validation of Morphology-based Identification of Two Cynoglossidae Larvae using Mitochondrial DNA (참서대과(Pisces: Cynoglossidae) 자어 2종의 미토콘드리아 DNA에 의한 형태동정의 타당성)

  • Kwun, Hyuck-Joon;Kim, Jin-Koo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.43 no.5
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    • pp.482-488
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    • 2010
  • Three specimens of Cynoglossidae larvae were collected from the southern Korean Sea in May and August of 2009, and were identified using morphological and molecular analysis. Specimens were divided into two groups based on the number of elongated dorsal fin rays on the top of the head: Cynoglossidae sp. A was defined as having two elongated dorsal fin rays, while Cynoglossidae sp. B possessed a single elongated dorsal fin ray. One specimen of Cynoglossidae sp. A, a post-larva with a notochord length (NL) of 5.8 mm was thought to be a Cynoglossus joyneri larva based on the presence of 115 dorsal pterogiophores, 85 anal pterogiophores, and 50 myomeres. Two specimens of Cynoglossidae sp. B, a 4.1 mm NL larva and a 11.3 mm NL juvenile, were thought to be Cynoglossus abbreviatus based on the presence of yolk in the former and 133 dorsal fin rays, 105 anal fin rays, and 63 myomeres in the latter. To test this morphology-based identification, molecular analysis was conducted using 419-422 bp of mitochondrial DNA 16S rRNA. Cynoglossidae sp. A was clearly matched to a Cynoglossus joyneri adult (d=0.000) and Cynoglossidae sp. B clustered closely with Cynoglossus abbreviatus adults (d=0.002). A neighbor-joining tree supported this robust relationship (bootstrap value=100%). Therefore, these molecular data validate the morphological identification of the two Cynoglossidae larval species.

Nomogram Estimating the Probability of Intraabdominal Abscesses after Gastrectomy in Patients with Gastric Cancer

  • Eom, Bang Wool;Joo, Jungnam;Kim, Young-Woo;Park, Boram;Yoon, Hong Man;Ryu, Keun Won;Kim, Soo Jin
    • Journal of Gastric Cancer
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    • v.15 no.4
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    • pp.262-269
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    • 2015
  • Purpose: Intraabdominal abscess is one of the most common reasons for re-hospitalization after gastrectomy. This study aimed to develop a model for estimating the probability of intraabdominal abscesses that can be used during the postoperative period. Materials and Methods: We retrospectively reviewed the clinicopathological data of 1,564 patients who underwent gastrectomy for gastric cancer between 2010 and 2012. Twenty-six related markers were analyzed, and multivariate logistic regression analysis was used to develop the probability estimation model for intraabdominal abscess. Internal validation using a bootstrap approach was employed to correct for bias, and the model was then validated using an independent dataset comprising of patients who underwent gastrectomy between January 2008 and March 2010. Discrimination and calibration abilities were checked in both datasets. Results: The incidence of intraabdominal abscess in the development set was 7.80% (122/1,564). The surgical approach, operating time, pathologic N classification, body temperature, white blood cell count, C-reactive protein level, glucose level, and change in the hemoglobin level were significant predictors of intraabdominal abscess in the multivariate analysis. The probability estimation model that was developed on the basis of these results showed good discrimination and calibration abilities (concordance index=0.828, Hosmer-Lemeshow chi-statistic P=0.274). Finally, we combined both datasets to produce a nomogram that estimates the probability of intraabdominal abscess. Conclusions: This nomogram can be useful for identifying patients at a high risk of intraabdominal abscess. Patients at a high risk may benefit from further evaluation or treatment before discharge.

Multiple SVM Classifier for Pattern Classification in Data Mining (데이터 마이닝에서 패턴 분류를 위한 다중 SVM 분류기)

  • Kim Man-Sun;Lee Sang-Yong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.3
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    • pp.289-293
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    • 2005
  • Pattern classification extracts various types of pattern information expressing objects in the real world and decides their class. The top priority of pattern classification technologies is to improve the performance of classification and, for this, many researches have tried various approaches for the last 40 years. Classification methods used in pattern classification include base classifier based on the probabilistic inference of patterns, decision tree, method based on distance function, neural network and clustering but they are not efficient in analyzing a large amount of multi-dimensional data. Thus, there are active researches on multiple classifier systems, which improve the performance of classification by combining problems using a number of mutually compensatory classifiers. The present study identifies problems in previous researches on multiple SVM classifiers, and proposes BORSE, a model that, based on 1:M policy in order to expand SVM to a multiple class classifier, regards each SVM output as a signal with non-linear pattern, trains the neural network for the pattern and combine the final results of classification performance.

Effects of Pride, Object Relevance and Message Type on Brand Attitude (메시지 유형의 브랜드태도효과에서 자긍심을 느낀 소비자의 객체관련성의 역할)

  • Choi, Nak-Hwan
    • Journal of Distribution Science
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    • v.15 no.6
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    • pp.57-64
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    • 2017
  • Purpose - The purpose of this study is to investigate the effect of brand message type on the object relevance between consumers and brands and to identify the mediation role of the object relevance in the effect of the message type on brand attitude. Research design, data, and methodology - Types of pride are classified into hubristic pride and authentic pride, and brand message types are divided into ability message and warmth message. Restaurant brand was selected by empirical study, and the experiment was performed with 2 (pride type: hubristic versus authentic) × 2 (message type: ability message versus warmth message) between-subjects design. The subjects of the experiment consisted of the undergraduates taking courses related to marketing. A preliminary step was taken to explore the difference in the perceived level of object relevance induced from each type of message between the consumer group that felt hubristic pride and the other group that felt authentic pride. This study analyzed the mediating role of the object relevance in the effects of the message type on brand attitude by means of Bootstrap method for each of the pride groups. Results - The results from the empirical analysis are summed up as follows. Regardless of pride types they felt in advance, consumers perceived their object relevance to be higher in the warmth information message than in the ability information message, and object relevance was analyzed to have a positive effect on brand attitude. It was analyzed that, regardless of pride types, object relevance played full mediation roles in the effect of warmth information versus ability information message on brand attitude. Conclusions - Based on the results, it may be suggested that marketers of a brand should endeavor to develop a warmth information message rather than a ability information message to prompt consumers to perceive the object relevance between their own brands and consumers, regardless of pride types, as long as a consumer feels pride in advance. In order to increase the consumers' attitude toward their brand, the brand marketers are solicited to check the object relevance between their brand and consumers, then, seek for the managerial ways to promote such object relevance.

A Mediation Analysis of Absorption Capacity by Bootstrapping Technique in Multiple Mediator Model (다중매개모델에서 bootstrapping기법을 이용한 흡수능력의 매개효과 분석)

  • Kim, Hyun-Woo;Lee, Hong-Bae;Shin, Yong-Ho
    • Journal of the Korea Society for Simulation
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    • v.24 no.4
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    • pp.89-96
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    • 2015
  • The mediation methods suggested by Baron and Kenny, Sobel, Aroian and Goodman, have widely used to test the mediating effect. However, as there are many problems in statistical test power, as well as statistical accuracy, a bootstrapping technique has been suggested as an alternative. In this paper, we adopt the phantom variables based on the bootstrapping technique to test the mediating effect in multiple mediator model consisting of three or more mediating variables. In particular, we formulate the multiple mediator model for analyzing the relations among organizational resources, the absorption capacity as mediating variables and technology commercialization capabilities. And using the bootstrapping approach, we analyzed the mediating effect of the absorption capacity by setting of phantom variables and calculated total indirect effect size and the statistical significance. The empirical results are as follows. First, we confirmed that the bootstrapping approach and the phantom variable is the very efficient and systematic mediation method. Second, we recognized that there is a difference in the mediating characteristics of the absorption capacity depending on the resource characteristics of human resources and material resources obviously.

SW Process improvement and Organization Change Management (SW 프로세스개선과 조직 변화관리)

  • Kim, Seung-Gweon;Jo, Sung-Hyun;Yoon, Joong-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.2
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    • pp.127-140
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    • 2013
  • We explored the relationship between the level of change awareness and deployment of software process improvement (SPI) approaches using a competing values framework. To measure awareness level of organization's change, we used DICE framework provides means for predicting the outcome of change management initiatives. The four factors for organizaton's change: duration, integrity, commitment, and effort are evaluated and a score is calculated. The DICE(R) score is used to classify projects into win, worry, or woe zones. In this paper, we apply the DICE(R) score as an independent variable to predict the outcome of a software process improvement. Our results indicated that the Organization have a higher chance of success have the better outcome in software process improvement.

Relationship between Life Stress and Gambling Behavior Perceived by University Students - The mediation effects of self-control and family support -

  • Jeong, Byeong-Il;Baek, Sang-Uk
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.1
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    • pp.89-97
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    • 2017
  • This study examined the structural relationship between life stress perceived by university students and their gambling behaviors through their self-control and family support. For this, it conducted the questionnaire on life stress, self-control, family support and gambling behavior with 387 university students attending universities in Gwangju city and analyzed the data collected. The results of the analysis were described below. As a result of analyzing the direct effects of life stress on gambling behavior, self-control and family support, it was found that the life stress had the positive effect on gambling behavior and it meant that when the university students couldn't cope with the life stress effectively and felt frustrated, they were likely to be involved in gambling behavior to escape from their helplessness. In addition, as a result of analyzing the direct effects of life stress on self-control and family support, it was found that life stress had negative effect on self-control and family support. The more experiences of life stress they had, the lower their self-control was. As their life stress was higher, they didn't make supportive relationship network with family members. As a result of mediating effects, it was shown that self-control and family support played the partially negative roles in the relationship between life stress and gambling behavior and it suggested that as the life stress was perceived less, self-control was performed better and as family support was higher, gambling behavior was effectively reduced. These results of the research suggested that life stress could be handled actively through self-control and family support and development and distribution of the program to cope with life stress could minimize the gambling behaviors. Also the limitations of this study and necessity of further studies were discussed.

Genetic Variation of the Mitochondrial Cytochrome b Sequence in Korean Rana rugosa (Amphibia; Ranidae)

  • Hyun Ick Lee;Dong Eun Yang;Yu Ri Kim;Hyuk Lee;Jung Eun Lee;Suh Yung Yang;Hei Yung Lee
    • Animal cells and systems
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    • v.3 no.1
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    • pp.89-96
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    • 1999
  • Nucleotide sequences of a 501 base-pair (bp) fragment in the mitochondrial cytochrome b (cyt b) gene were analyzed for 12 populations of Rana rugosa from Korea and Japan using a polymerase chain reaction (PCR) and direct silver sequencing. Two genetically distinct groups (type-A and type-B) were found in Korea. Type-A was found throughout most of South Korea and type-B was restricted to the mid-southeastern regions (Samchok, Yongdok, Chongsong and Pohang). But in the Tonghae population, both types were found. The level of mitochondrial DNA (mtDNA) sequence differences ranged from 0% to .0.8% among six populations of type-A, and 0 to 1.0% among 4 populations of type-B. However, sequence differences between type-A and type-B ranged from 5.4% to 6.6%, Using Kimura's two-parameter distance, the level of genetic sequence divergence between type-A and type-B was 6.7%. The Japanese R. rugosa was clustered very far from the Korean R. rugosa with 14.7%. In the neighbor-joining and UPGMA tree, all Korean samples were grouped, but subdivided into two types in 99% of the bootstrap iteration.

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