• Food Science and Preservation
• /
• v.23 no.3
• /
• pp.438-444
• /
• 2016

This study was performed to determine the optimal freezing point for the reliable cold storage of Korean agricultural products, and to provide basic data for determining the storage temperature based on the quality characteristics. Additional supercooling temperature analysis was conducted to explore the possibility of supercooling storage. To determine the effects of quality characteristics on the freezing point, the hardness, acidity, moisture and sugar content were analyzed. The crops were frozen using customized cooling unit and their freezing and supercooling points were determined based on their heat release points. The freezing temperatures of garlic, leek, cucumber, hot pepper, grape, oriental melon, netted melon, peach, cherry tomato, plum, daikon, sweet persimmon, apple, sweet potato, mandarin, pear, and strawberry were -1.6, -0.5, -0.5, -0.7, -1.6, -1.6, -1.3, -0.8, -0.3, -1.1, -0.3, -1.7, -1.5, -1.5, -0.8, -1.5, and -$0.9^{\circ}C$, respectively; otherwise, supercooling points were -7.8, -3.7, -3.3, -4.9, -5.7, -4.6, -2.8, -3.3, -5.9, -4.2, -0.8, -4.7, -3.2, -3.7, -4.7, -4.2, and -$3.4^{\circ}C$, respectively. These results suggest that the ideal freezing temperature of crops could be estimated through freezing point depression because of their sugar content, and this technique should be used to maintain an optimum storage temperature. However, cold storage is complicated and further study is required because of the effects of long-term cold storage on the crops.

• The Journal of Fisheries Business Administration
• /
• v.26 no.2
• /
• pp.53-74
• /
• 1995

The purpose of this paper is to compare China's and Korea's marine fisheries industries in order to present the main features of China's marine fisheries and show the comparative advantages they have in production. The results indicate that China's marine fisheries have the following features. (1) The marine proportion of the fisheries industry economic activity is less than 60%. Fishing is 71.3% of that marine activity. (2) The production trends of marine fisheries history in China can be classified as follows: 1) an early growth period, 2) a deliberation/consolidation period, 3) a second growth period, 4) a third growth period, and 5) a fourth growth period. The growth rate has rapidly increased recently. (3) Fish production is over 70% of marine fishing fisheries, the next major product is crustacea. The production of shellfish occupies over 70% of marine aquaculture, seaweed production however, is only 22% of total marine aquaculture. (4) The licensed area for marine aquaculture in China is 586.3 ha and that area is 5.4 times larger than that of Korea. The allotted area for shellfish aquaculture is 60% of marine aquaculture, production areas of crustaceans occupy 27.3%, fish has 7 1%, and seaweed production only 5.7% of allocated marine aquaculture areas. (5) The proportion of power vessels for marine fisheries of China's total power vessel fleet is around 65%, and the marine fisheries portion of non - powered vessels constitutes only 12%. The highest proportion of power vessels engaged in marine fisheries activities is between 10 tonnes to 100 tonnes. (6) The portion of marine fishery workers of all fishery industry employees is 22%, and 70% of them are full - time workers. Of marine fishery workers, 64% are in the fishing sector, 22%, aquaculture workers, and the number of employees in marine fisheries is increasing every year. The analysis of China's fishery industry in the production competitiveness indicates as follows : (1) The licensed areas in marine aquaculture, number of fishing vessels, number of marine fishing workers in China's fishery industry are much more than those of Korea's. Therefore China is much more competitive than Korea in the quantity of production side. However, licensed areas for seaweed aquaculture are more extensive in Korea than China. In China, the number of power vessels of between 10 tonnes and 100 tonnes, the licensed shellfish aquaculture areas, and the number of fishing workers within the fisheries industry are much more than those of Korea. (2) It is estimated that the licensed areas in marine aquaculture, number of medium sized power vessels, number of marine fishery workers will be increased as the quantity of production factors grow in China. (3) At present, yield per Ha. in marine cultures is very low in China. Therefore it is estimated that aquaculture techniques have only been diffused recently in China. Yield of fish per Ha especially is much lower than that of Korea. So the level of aquaculture techniques seems much lower than that of Korea. (4) China is behind Korea in production technique, however the number of HP per boat in China is lower than that of Korea. Therefore, China is much more competitive than Korea in Costs. (5) Average fish catches per marine fishery worker in China is only 1/3 that of Korea's, and average marine aquaculture production in China is only 1/2 that of Korea. Therefore we can say Korea is more competitive than China in efficiency. The average income of marine fishery workers in China is higher that that of other Chinese industries. However, the competitiveness of the fisheries industry in China will be increased as more capital is invested and advanced techniques are developed.

• Journal of dental hygiene science
• /
• v.6 no.4
• /
• pp.295-302
• /
• 2006

This study was conducted to study the effects of the TA Theory and the TA Program, an educational testing tool developed to improve functional communication skills for dental hygienists. The results taken from the experiment using the TA program has been verified by Examination Tool for Personnel Communication developed by Chung(2001). 44 in two experimental groups and 16 in control group took part in TA Program training sessions. The experimental Group I received TA technique training session for 12 hours per day in a period of three days and Group II for 6 hours per day in a period of two days. From this experiment, the following conclusion was obtained. The results are as follows: 1) As it can be seen from the results of the examination taken prior to the experiment, the subjects of the control group and experimental groups were homogenous in all categories including self-disclosure, awareness, evaluation and acceptance of feedback, self-expression, coping with feelings, clearness, avoidance, dominance, handling of differences, and perceived acceptance. 2) After the training of TA Program was completed on Group I and II, the examination results are as follows: Control Group (1.5158), Group I (1.8260) / Control Group (1.4684), Group II (1.9985). The results of Group I and II (1.7970 and 1.9985 respectively) therefore showed a meaningful difference. 3) From the results of the experiment it is shown that dental hygienists' communication skills improved after receiving the TA Program training. Therefore TA Program may be used as an effective tool for such purpose. 4) As it can be observed from the data, Group I and II showed difference in the degree of improvements. Therefore, there needs to be a further investigation on the effects of the difference in training period. 5) This program is not only limited to the education of dental hygienists but may be widely applied to various forms of education and teaching methods.

• Journal of Environmental Health Sciences
• /
• v.37 no.2
• /
• pp.102-112
• /
• 2011

Objectives: The purpose of this study is to analyze the effects of chronic exposure by welders to manganese (Mn) through an analysis of the degree of brain activity in different activities such as cognition and motor activities using the neuroimaging technique of functional magnetic resonance imaging (fMRI). The neurotoxic effect that Mn has on the brain was examined as well as changes in the neuro-network in motor areas, and the usefulness of fMRI was evaluated as a tool to determine changes in brain function from occupational exposure to Mn. Methods: A survey was carried out from July 2010 to October 2010 targeting by means of a questionnaire 160 workers from the shipbuilding and other manufacturing industries. Among them, 14 welders with more than ten years of job-related exposure to Mn were recruited on a voluntary basis as an exposure group, and 13 workers from other manufacturing industries with corresponding gender and age were recruited as a control group. A questionnaire survey, a blood test, and an fMRI test were carried out with the study group as target. Results: Of 27 fMRI targets, blood Mn concentration of the exposure group was significantly higher than that of the control group (p<0.001), and Pallidal Index (PI) of the welder group was also significantly higher than that of the control group (p<0.001). As a result of the survey, the score of the exposure group in self-awareness of abnormal nerve symptoms and abnormal musculoskeletal symptoms was higher than those of the control group, and there was a significant difference between the two groups (p<0.05, respectively). In the correlation between PI and the results of blood tests, the correlation coefficient with blood Mn concentration was 0.893, revealing a significant amount of correlation (p<0.001). As for brain activity area within the control group, the right and the left areas of the superior frontal cortex showed significant activity, and the right area of superior parietal cortex, the left area of occipital cortex and cerebellum showed significant activity. Unlike the control group, the exposure group showed significant activity selectively on the right area of premotor cortex, at the center of supplementary motor area, and on the left side of superior temporal cortex. In the comparison of brain activity areas between the two groups, the exposure group showed a significantly higher activation state than did the control group in such areas as the right and the left superior parietal cortex, superior temporal cortex, and cerebellum including superior frontal cortex and the right area of premotor cortex. However, in nowhere did the control group show a more activated area than did the exposure group. Conclusions: Chronic exposure to Mn increased brain activity during implementation of hand motor tasks. In an identical task, activation increased in the premotor cortex, superior temporal cortex, and supplementary motor area. It was also discovered that brain activity increase in the frontal area and occipital area was more pronounced in the exposure group than in the control group. This result suggests that chronic exposure to Mn in the work environment affects brain activation neuro-networks.

• Journal of the Korean earth science society
• /
• v.32 no.6
• /
• pp.665-673
• /
• 2011

In order to estimate the hydrocarbon reserves, the porosity of the reservoir must be determined. The porosity of the area without a well is generally calculated by extrapolating the porosity logs measured at wells. However, if not only well logs but also seismic data exist on the same site, the more accurate pseudo porosity log can be obtained through artificial neural network technique by extracting the relations between the seismic data and well logs at the site. In this study, we have developed a module which creates pseudo porosity logs by using the polynomial neural network method. In order to obtain more accurate pseudo porosity logs, we selected the seismic attributes which have high correlation values in the correlation analysis between the seismic attributes and the porosity logs. Through the training procedure between selected seismic attributes and well logs, our module produces the correlation weights which can be used to generate the pseudo porosity log in the well free area. To verify the reliability and the applicability of the developed module, we have applied the module to the field data acquired from F3 Block in the North Sea and compared the results to those from the probabilistic neural network method in a commercial program. We could confirm the reliability of our module because both results showed similar trend. Moreover, since the pseudo porosity logs from polynomial neural network method are closer to the true porosity logs at the wells than those from probabilistic method, we concluded that the polynomial neural network method is effective for the data sets with insufficient wells such as F3 Block in the North Sea.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.23 no.3
• /
• pp.249-257
• /
• 2007

State of problem : The use of zirconium oxide all-ceramic material provides several advantages, including a high flexural strength(>1000MPa) and desirable optical properties, such as shading adaptation to the basic shades and a reduction in the layer thickness. Along with the strength of the materials, the cementation technique is also important to the clinical success of a restoration. Nevertheless, little information is available on the effect of different surface treatments on the bonding of zirconium high-crystalline ceramics and resin luting agents. Purpose : The aim of this study was to test the effects of surface treatments of zirconium on shear bond strengths between bovine teeth and a zirconia ceramic and evaluate differences among cements Material and methods : 54 sound bovine teeth extracted within a 1 months, were used. They were frozen in distilled water. These were rinsed by tap water to confirm that no granulation tissues have left. These were kept refrigerated at $4^{\circ}C$ until tested. Each tooth was placed horizontally at a plastic cylinder (diameter 20mm), and embedded in epoxy resin. Teeth were sectioned with diamond burs to expose dentin and grinded with #600 silicon carbide paper. To make sure there was no enamel left, each was observed under an optical microscope. 54 prefabricated zirconium oxide ceramic copings(Lava, 3M ESPE, USA) were assigned into 3 groups ; control, airborne-abraded with $110{\mu}m$ $Al_2O_3$ and scratched with diamond burs at 4 directions. They were cemented with a seating force of 10 ㎏ per tooth, using resin luting cement(Panavia $F^{(R)}$), resin cement(Superbond $C&B^{(R)}$), and resin modified GI cement(Rely X $Luting^{(R)}$). Those were thermocycled at $5^{\circ}C$ and $55^{\circ}C$ for 5000 cycles with a 30 second dwell time, and then shear bond strength was determined in a universal test machine(Model 4200, Instron Co., Canton, USA). The crosshead speed was 1 mm/min. The result was analyzed with one-way analysis of variance(ANOVA) and the Tukey test at a significance level of P<0.05. Results : Superbond $C&B^{(R)}$ at scratching with diamond burs showed the highest shear bond strength than others (p<.05). For Panavia $F^{(R)}$, groups of scratching and sandblasting showed significantly higher shear bond strength than control group(p<.05). For Rely X $Luting^{(R)}$, only between scratching & control group, significantly different shear bond strength was observed(p<.05). Conclusion : Within the limitation of this study, Superbond $C&B^{(R)}$ showed clinically acceptable shear bond between bovine teeth & zirconia ceramics regardless of surface treatments. For the surface treatment, scratching increased shear bond strength. Increase of shear bond strength by sandblasting with $110{\mu}m$ $Al_2O_3$ was not statistically different.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.26 no.1
• /
• pp.135-170
• /
• 2015

This study aimed to investigate the transition of academic libraries' jobs by developing a model based on a shift of library generations including Library 1.0, Library 2.0, and Library 3.0 corresponding to the shift of web generations and to explore generational characteristics of library duties as well. The research used three phases of procedure: literature review about different library generations; job analyses for academic libraries in South Korea and the U.S.A.; the Delphi technique in tree sequential order. The research findings were as follows. First of all, there were 170 duties that continued from Library 1.0 to Library 3.0. There were 58 duties which continued from Library 2.0 to Library 3.0 whereas three duties that continued from Library 1.0 to Library 2.0. In addition, three distinctive duties existed only in Library 1.0 whereas one unique duty was only in Library 2.0. Library 3.0 generated 25 new duties. Secondly, considering general characteristics which cover specific parts of individual duties, there was a significant increase in importance, difficulty, and frequency of library administration throughout the three generations. In terms of importance, difficulty, and frequency of collection development and management, there was a significant increase only from Library 2.0 to Library 3.0. Considering information organization, there was a significant decrease in importance from Library 1.0 to Library 2.0. In addition, there was a significant decrease in frequency and there was no significant difference in difficulty throughout the three generations. In the case of information service, while there was a significant increase in importance among three generations, there was a significant increase in difficulty only from Library 1.0 to Library 2.0. However, there was no generational difference in frequency. With the respect of information system development and management, there was a significant increase in importance and frequency throughout the three generations, but there was no significant difference in difficulty among three generations.

• KSBB Journal
• /
• v.22 no.5
• /
• pp.356-361
• /
• 2007

Cyanobacteria are a very old group of prokaryotic organisms that produce very diverse secondary metabolites, especially non-ribosomal peptide and polyketide structures. Although some cyanobacteria produce lethal toxins such as microcystins and anatoxins, some may be useful either for development into commercial drugs or as biochemical tools. Detection of unknown secondary metabolites was carried in the present study by a screening of 98 cyanobacterial strains from Cyanobiotech GmbH in order to establish a screening process, isolate pure substances and determine their bioactivities. A degenerated polymerase chain reaction technique as molecular approaches has been used for general screening of NRPS gene and PKS gene in cyanobacteria. A putative PKS gene was detected by DKF/DKR primer in 38 strains (38.8%) and PCR amplicons resulted from a presence of NRPS gene were showed by MTF2/MTR2 primer in 30 strains (30.6%), respectively. A screening of interesting strains was performed by comparing PCR screening results with HPLC analyses of extracts. HPLC analysis for a detection of natural products was performed in extracts from biomass. 5 strains were screened for further scale-up processing. 7 pure substances were isolated from the scale-up cultures and tested for bioactivities under consideration to purity, amount and molecular weight of substances. One substance isolated from CBT 635 showed cytotoxic activity. This substance may be regarded as Microcystin LR.

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

• Journal of the Korean Institute of Landscape Architecture
• /
• v.41 no.1
• /
• pp.44-50
• /
• 2013

The persons in charge of management request diagnosis and prescription to tree hospitals in order to get consultation about the problems like blight that occur in landscape tree management. This study aims to analyze what the main problems and questions raised by landscape gardeners are and those concerned in landscape tree management. This is done by investigating landscape tree-related questions and answers uploaded on the online consultation boards of the plant diagnostic centers approved in Korea including the Seoul National University Plant Clinic, the Chungbuk National University Plant Hospital, and the Kangwon Diagnostic Center. As a result, those concerned in landscape occupied the most as 81.4% among the questioners. However, only 11.5% did explain the plant management history or surrounding environment, which is essential for landscape tree diagnosis when asking questions. This shows that those concerned in landscape lack basic knowledge or interest about plant diagnosis. Among 263 questions about landscape trees, questions about physiological damage included 94 cases that were the most taking up 35.8%. Moreover, the next were damage by insects and damage by disease in order. It is thought that due to the characteristics of physiological problems that occur by various sorts of stress and with no signs, they tend to request diagnosis or prescription the most. The most frequent reasons for physiological damage are water stress and temperature stress. About damage by disease, there exist many types of diseases, and there are many complex damages accompanied by physiological causes. About damage by insects, the most common include damage by moths. In consideration of this result, universities or technician training centers should provide education for landscape tree management so that landscape technicians and students can acquire essential knowledge and information about landscape tree management and increase their interest in it. In particular, it is necessary to provide profound learning opportunities for plant physiology, and the technicians should make efforts themselves. In addition, it is needed to build organizations to which they can ask technical questions about landscape planting and management in order to understand landscape industry in general and the actual status of landscape planting technique and the actual field. Moreover, to elevate systemicity and expertise in the area of landscape tree management not yet equipped with the foundation, it is needed to cultivate the technicians intensively and conduct research by those concerned both in academic and industrial circles.