• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.656-664
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• 2010

We investigated the levels and distribution patterns of 16 priority polycyclic aromatic hydrocarbons (PAHs), 12 Coplanar polychlorinated biphenyls (Co-PCBs) and organochlorine pesticides (OCPs) in the surface sediments from the Nakdong river basin, Korea. The levels of 16 PAHs and 12 Co-PCBs in the river sediment samples ranged from not detected (N.D.)~969.3 ng/g-dry, 4.2~7716.5 pg/g-dry (0.0~10.1 pg-TEQ/g-dry), respectively. Also, the levels of 16 PAHs were from 5.8~2987.2 ng/g-dry and 4.3~461.1 pg/g-dry (0.0~0.6 pg-TEQ/g-dry) for 12 Co-PCBs in the lake sediment samples. Only dichloro-diphenyl-trichloroethane (DDT) were detected among target OCPs and the concentration ranged from N.D.~1.5 ng/g-dry in the river sediment samples. These contamination levels were far below the guideline values suggested for environmental quality assessment. Low molecular weight PAHs were dominant in the river sediment samples, while middle and high molecular weight PAHs were dominant among 16 PAHs in the lake sediment samples. PCB-118 and PCB-105 were predominant congeners in the sediment, which were similar to the results obtained from previous studies. With these results, the assessment of potential sources of PAHs and Co-PCBs contamination in the sediments of the Nakdong river basin was performed. The pyrogenic-PAHs originated from combustion of fossil fuel and biomass were related with the PAHs contribution in most of the sediment samples, and Co-PCBs in the sediment samples were related with commercial PCB products.

• Journal of Navigation and Port Research
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• v.40 no.4
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• pp.197-205
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• 2016

Our country, which relies on maritime transport a majority of import and export trade volume and faced with unexpected accidents, it is difficult to operate the normal function of container terminal. It also caused by reliability issue raised is likely to be given a blow to the new volumes to attract and maintain existing volumes. Under this views, the container terminal is a situation that highlights the role of the harbor workers and cope with aggressive work to provide the best quality services to customers 365 days. On these grounds, the heavy work burden is passed on to the harbor workers and caused accidents every year. The study was analyzed the safety status of the container terminal under the real following the conditions as disaster status analysis, insufficient safety training circumstances and safety training from 2012 year to 2015 in the target current K.Y terminal. As a result of equipments safety training analysis, it shows that 2012 year happened 45 cases and 31 cases in 2013 year until not practicing the training over the Gantry Crane equipment. One hand 23 cases took place in 2014 while preparation training and the other intensive training period of 2015, 8 cases occurred. it shows that 2012 year happened 13 cases and 19 cases in 2013 year until not practicing the training over the Transfer Crane equipment. One hand 12 cases took place in 2014 while preparation training and the other intensive training period of 2015, 8 cases occurred. it shows that 2012 year happened 9 cases and 9 cases in 2013 year until not practicing the training over the Yard Tractor equipment. One hand 9 cases took place in 2014 while preparation training and the other intensive training period of 2015, 4 cases occurred. Because safety training of the container terminal was given to greatly impact on the mandatory safety training, self-educational enforcement and specified equipments safety training, hence the container terminal is to strengthen the safety education to prevent accidents in advance.

• Korea journal of population studies
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• v.19 no.1
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• pp.139-159
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• 1996

This study comparatively examines a causal model of employee attatchment which focuses on employee's organizational commitment and intent to stay with an organization. This study is based on two separate studies of employee attachment among teachers : the U.S. case of the Chicago Public Schools (CPS) and the South Korean case of the Seoul Educational District (SED). The main purpose of this study is to replicate in Korea the CPS study. A revised model based on the unique characteristics of Korean teachers is also developed and estimated. The Price Mueller model of employee attachment provides the basic theoretical framework for this study. It includes five general classes of variables : 1) employee responses to work variables : job satisfaction, commitment, and intent to stay; 2) psychological stress variables: role ambiguity, role conflict, work overload, and quality of students; 3) social structural variables: autonomy, routinization, distributive justice, and legitimacy; 4) economic structural variables: pay, job security, promotional opportunities, and job opportunities; and 5) work orientation variables : career commitment, normative commitment, work motivation, affectivity, work values, and met expectations. The data was collected through questionnaire survey and a sample of 649 secondary school teachers in Seoul, South Korea, was included in the final analysis. Covariance structure analysis (LISREL) was used to estimate the causal model. The results indicate that the endogenous variables of job satisfaction and commitment play a considerably less important role than in the U.S. model in mediating the effects of the exogenous variables on intent to stay, and the model fails to explain the majority of the variance in intent to stay. In addition, the new variables added to the revised Korean model do not bave significant effects on intent to stay. The structural characteristics of the employment relationship and labor markets associated with Korean teachers forced mobility and closed external markets - are largely accountable for the major differences between the Korean and the U.S. cases. The study suggests that conceptual and empirical work on what produces employee attachment under these structural constraints needs to receive more attention in future studies.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.334-344
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• 2020

A total of 24 families, 44 species, and 658 benthic macroinvertebrates were identified, and Ecdyonurus dracon Kluge (13%) was the dominant species in forested streams within the Yeonyeopsan (Mt.). A total of four habit categories (i.e., clingers (56%), burrowers (19%), swimmers (14%), and sprawlers (56%)) were identified, and clingers were the dominant habit at all survey points except point one (UP1). Habitat characteristics were depended on the hydraulic factors (e.g., flow velocity, depth, and substrates), water quality (e.g., DO and water temperature), and the habitat characteristics were differed in the riffle, which has a faster the flow velocity, compared by in the stagnant pool. In other words, in riffles, the clingers dominated in high flow velocity with the large maximum and median grain size for substrates in the habitats regardless of depth, but the burrowers and sprawlers were dominant in low flow velocity with the small maximum and median grain size for substrates in the habitats. Moreover, DO and flow velocity were in positive correlation (y = 0.6666x - 0.659, R² = 0.0851), and the habitat for burrowers was wider than that for sprawlers or clingers. The water depth was negatively correlated with water temperature (y = -26.397x + 283.87, R² = 0.1802) since the water temperature is more sensitive to insolation in shallow depth. pH was positively correlated with water temperature. The investigation of the habitat characteristics by separating the relations between pH and DO in upstream and downstream showed the low pH and high DO in the upstream with a high crown density of 68%, regardless of community composition. On the other hand, high pH and low DO in the downstream with a relatively low crown density of 51%. It was considered that the riparian forest played a role in suppressing the growth of attached algae and the controlling water temperature in headwater streams. Our findings identified the habitat characteristics of benthic macroinvertebrates in a headwater stream. We expected that the finding can provide reference data for suggesting conservation and management plans in a headwater stream and increasing academic value.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.205-212
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• 1979

Red pepper paste were prepared by using various raw materials such as rice, glutinous rice, polished barley, polished wheat and corn powder, and their chemical compositions including reducing sugar, amino-N and ethanol were analyzed during the period of aging in order to elucidate effects of these starchy materials on the compositions and qualities of the products. The results obtained are summarized as follows: 1) Koji of these materials were manufactured respectively by inoculating a strain of Asporyzae and their activities of protease and saccharifying amylase were determined. Wheat koji was found to have the highest level of protease activity among the koji, while glutinous rice koji had the strongest amylase activity. 2) Contents of moisture, crude protein, crude fat, and sodium chloride in the red pepper pastes were not changed significantly, however total sugar content was decreased during the period of aging. 3) After 60 days of aging, the highest amount (160mg%) amino nitrogen was detected in the red pepper paste of polished wheat, but higher levels of reducing sugar and ethanol contents were detected in that of glutinous rice. 4) Amino acids in the products were analyzed after 60 days of aging: a) Total 17 amino acids were detected. b) Free amino acid ratio to total amino acid content was approximately 35 percent in average. c) Free glutamic acid was higher than any other free amino acid In the amount and free ratio, but free methionine was lower. d) Lysine content was relatively high, while histidine and glycine were detected in trace. 5) Sensory tests including color, odor and taste on the products resulted in the highest mark for the red pepper paste of glutinous rice but in the lowest mark for that of corn powder.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.52-67
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• 1998

The investigative research on the mammalian milk purely consisted of the physiological quality of lactoferrin was conducted to reveal the antimicrobial ativity of specifically functional foods with antibiotic characteristics as a basic data in food manufacturing. Bovine lactoferrin were isolated from raw milk samples, and was digested with pepsin, trypsin and chymotrypsin. It was necessary then to separate and purify lactoferrin from bovine raw milk, and in order to analyze the antimicrobial activity of the enzyme-treated bovine lactoferrin in their required quantitative fraction. Afterwards Escherichia coli and Staphylococcus aureus was incubated in it. It was that investigated to enzyme-treated fractions molecular weight and the peptide fragment with antimicrobial effect. 1. The purity of enzyme-treated bovine lactoferrin(BLF) was tested by SDS-PAGE. As a results of 12% SDS-PAGE assay, pepsin-treated LF did not exhibited band until if reaches 14 KDa, while trypsin and chymotrypsin treated LF, known to contain the non-digestive lactoferrin exhibited band at a molecular weight of 33 KDa. 2. Bovine lactoferrin was sucessfully purified through the use of Sephadex G-50 Column. In order to assay LF through the Sephadex G-50 column chromatography, the digestive bovine lactoferrin (BLFs) was eluted with a linear gradient of 0.05% Tris-HCl. When the gel-filtration analysis, pepsin, trypsin and chymotrypsin treatments of BLF fragments was showed 2, 3, and 2 peak, respectively. The results of the HPLC analysis confirmed that had a non-digestive lactoferrin receptor, and trypsin and chymotrypsin treated BLFs has an antimicrobial effect. 3. To measure the strength of the antimicrobial effect of enzyme treated lactoferrin it was compared to the antimicrobial activity taking place at the incubated Escherichia coli and Staphylococcus aureus. This might explain the resistance of the microorganisms for peptide fragment. The pepsin-treated of bovine lactoferrin was markedly reduced by incubation of the cells. Trypsin-treated of BLF was similar to chymotrypsin-treated of BLF. However, trypsin and chymotrypsin treatments of BLFs were showed the antimicrobial effect until eight hours incubation for native bovine lactoferrin. Therefore the enzyme-treated lactoferrin have an antimicrobial effect even non-digestive lactoferrin. 4. The digestive bovine lactoferrin fragments assay was carried out by the use of Sephadex G-50 column chromatography and SDS-PAGE. The pepsin and chymotrypsin-treated fragments has a low molecular weight and trypsin-treated lactoferrin was only showed a band. It was described that characteristics of digestive protein. It appeared that there may be a relation between virulence and resistance to enzyme-treated BLF.

• Korean Journal of Agricultural Science
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• v.20 no.2
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• pp.153-166
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• 1993

The experiments were conducted to improve raw milk quality during storage, the chemical composition and microbiological aspect of raw milk, milk thermized at $65^{\circ}C$ for 30 second, and $75^{\circ}C$ for 2 second stored at $5^{\circ}C$ for 4 days were investigated. The result obtained were summarized as follows : 1. During storage of raw and thermized milk, in the composition of milk fat, milk protein, lactose and total solid did not change significantly. 2. The range of pH and acidity for the raw milk were 6.73~5.94 and 0.16~0.27% respectively and those of the thermized milk were 6.79~6.62 and 0.16~0.17% respectively. The phosphatase test were negative in heated milk. 3. The composition of total nitrogen, NCN and whey protein were decreased, wherease those of NPN and casein were increased in heat treated milk. 4. The compositions of total nitrogen and casein were decreased as the storage period advanced, wherese those of NCN and NPN were increased. However, the composition of whey protein did not significantly change. 5. The number of coliform bacteria was not found in thermized milk. but were gradually increased in raw milk during storage period. 6. Raw milk had total bacteria count as $5.6{\times}10^6/ml$, psychrotrophic bacteria $1.8{\times}10^6/ml$ and thermoduric bacteria $1.6{\times}10^5/ml$, as the heat treatment increased microorganism counts decreased to milk thermized at $75^{\circ}C$, for 2 sec. $3.0{\times}10^3/ml$, $1.5{\times}10/ml$ and $2.7{\times}10^3/ml$ respectively. 7. The count of thermoduric bacteria, psychrotrophic bacteria and total bacteria were increased during storage period, and more rapidly increased in raw milk than in heat treated milk.

• Journal of The Korean Association For Science Education
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• v.37 no.2
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• pp.347-358
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• 2017

The purpose of this study is to research on the professional development of pre-service chemistry teachers in terms of personal practical knowledge(PPK), and draw a discussion for pre-chemistry teacher education. A reflective discussion through a Community of Practice(CoP) activity has been conducted with 5 pre-service chemistry teachers studying in a college of education located in Seoul. The analysis of the results reveals that 'Subject-matter knowledge' is leaning toward massive chemical contents, 'Curriculum knowledge' is below the level of selecting, analyzing, and applying curriculum materials. 'Instruction knowledge', especially the knowledge of chemistry experiment and research, is not enough to lead secondary students' scientific experiment. 'Milieu of school knowledge' is stunted in growth for the reason of communication-deficiency between a college of education and a community, and among education- related groups. 'Self-knowledge' has been diminished not only because there is a bad influence from college classmates not wanting to be a teacher, but also a lack of communication in the chemistry-education department which can make pre-teachers' belief strong. In conclusion, it is especially needed for the chemistry-education department to strengthen pre-teachers' 'Self-knowledge' in order to develop PPK. This study suggests operating 'a professional community' that has a periodic meeting with pre-service teachers, teachers, professors, community people, education practitioners, and researchers. In addition, it would be effective for increasing pre-teachers' PPK to reconsider depth and direction of 'Subject-matter knowledge', to give an opportunity to examine curriculum materials critically and reorganize them, to improve the course of chemistry experimental subject to the way of improving pre-teachers' leadership in chemistry inquiry experiment, and to raise the quality of educational service activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.278-285
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• 2013

We investigated foodservices and levels of their satisfaction from parents of children in kindergartens with and without dietitians. Foodservice facilities consisted of kitchens and cafeterias for all kindergartens with a dietitian (KWD) and only kitchens for all kindergartens without a dietitian (KWOD) (p<0.001). Children consumed lunch in a lunchroom for all KWD and in a classroom for all KWOD (p<0.001). The person in charge of the diet menu was a dietitian for all KWD and a director for 52.2% of KWOD (p<0.001). About 48% of total kindergartens were served different amounts according to the child's age and body size. About 30% of parents from total kindergartens responded that a difficulty of foodservice management was children's safety while distributing the lunch. The majority of respondents claimed that foodservices need a more balanced menu and active instructions on proper dietary habits. Parents who visited and participated in foodservice were significantly higher from KWD than KWOD. Also, the desire to participate in foodservices was significantly higher in the parents from KWD (p<0.01). Sixty one percent of parents from KWD and 19% of parents from KWOD considered foodservices when choosing a kindergarten (p<0.001). The satisfaction in foodservices of parents from KWD was significantly higher from all points of view in terms of the quality of foodservice, nutrition, and hygiene. In conclusion, we found that foodservices and their levels of satisfaction from parents of kindergartens with dietitians were better and higher than those without dietitians. Therefore, all kindergartens should consider having a dietitian exclusively in charge of foodservices.

• Journal of Korean Academy of Nursing
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• v.24 no.4
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• pp.623-634
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• 1994

Although the average menopausal age has not changed, women's life span has increased. Today's women live longer after their menopause than those in the past, and this calls for attention in both nursing and medical fields. Many studies have revealed how women reacted to menopause and suffered from it. But they did not discriminate the menopausal meaning and effects from the climacteric phenomena. So, this author tried to clarify what menopause itself meant to the climacteric women, by means of grounded theory methodology. The interviewees were 21 women, whose ages were between 46 and 60 years. They were selected by theoretical sampling technique, and the author tried to include all levels of important variables such as age, educational background, religion and job. Data were collected by the author through in -depth interviews and observations in July, 1994. The interviews were mostly done in the homes of the subjects, or in some cases at the author's office or in a hospital. Interviews took from 30 minutes to 2 hours. Interviews were tape recorded and transcribed later by a research assistant. Data were analyzed as gathered, by the constant comparative method proposed by Strauss and Corbin. Eleven concepts were discovered from the data, and they were grouped under six higher order categories. These six categories were "to give menopause a meaning", "to experience value change", "to have self-help strategies", "to have no strategies", "to live a life worth living", "to have a sense of powerlessness" Among these "to experionce value change" was . selected as the core category. Five major categories were systematically integrated around the core category. Women's adaptation to menopause was defined as proceeding as follows : Most women felt relief and sorrow at the same time when they faced menopause, and some only sorrow or agony. Then, they consulted with others about menopausal symptoms, or tried to think of them by themselves. Finally, they gave menopause a meaning, which was that menopause and its symptoms were natural phenomena. But menopause made women reflect on them-selves and their past lives. As they reflected on themselves, their value on life began to change. As their value changed, some women seeked self help strategies. Those self help strategies were what they had learned from collegues, professionals or mass media. The quality of their lives depended on whether they practiced self help strategies or not. Three types of lives were found. Twelve women enjoyed a life worth living, and practiced the self help strategies, because they accepted menopause a chance to change. They were characterized by a high educational level, having a professional job and a sincere faith in God. Seven women were living as usual, because they did not have the necessity to change. They were high school graduates and house wives. Two women recognized menopause a chance to change, but they did not try self help strategies. Their characteristic was low educational level. Those who did not try self help strategies complained of powerlessness to varying degrees. The educational background, full-time jobs and faith helped women adapt to menopause positively. But social support was not helpful to women's adaptation to menepause. Three hypotheses were derived from the analysis. (1) The higher the educational level, the more theneed to change. (2) Women with higher educational background will practice self help strategies more than those with lower edcational background. (3) The more women practice self help strategies, the worthier lives they will live. Suggestions for further studies are as follows. (1) Studies to test hypotheses are needed. (2) A study to find the relationship between the degree of practicing self help strategies and locus of control. (3) Spiritual approaches would better be applied to help menopausal women. (4) Education through mass media should be given mere frequently.