• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.307-312
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• 1984

The dried pure shells deprived of soft tissues were subjected to analysis of chitin-protein complexes from 5 species of marine crustaceans, including 2 species of crabs and 3 species of shrimps. The protein fractions were obtained from chitin-protein complexes under the varying conditions of extractions and the crude chitin was prepared from the shells by the sulfurous acid process. The crude chitin was purified through the extraction with several organic solvents such as dimethyl-acetamide, N-methylpyrrolidone. The purified chitin was also examined using the phase contrast microscope. Total protein contents of the shells were diverse, showing 9.6% for Portunus trituberculatus, 3.1%, Charybdis bimaculata, 9.4%, Penaeus japonicus, 10.9%, Metapenaeus intermedius and 5.8%, Squilla oratoria. Covalently bound protein varied with species from 2.1% for Charybdis bimaculata to 9.9% for Metapenaeus intermedius. The puified chitin contents of the shells were shown to 21.1% for Portunus tritube rculatus, 6.2%, Charybdis bimaculata, 20.2%, Penaeus japonicus, 27.1%, Metapenaeus intermedius and 25.5%, Squilla oratoria. Exceptionally low analytical value obtained with Charybdis bimaculata are supposed to be due to the very young subjects. The ratios of chitin to covalently bound protein in the shells were various such as 2.7 to 1 for Portunus trituberculatus, Penaeus japonicus and Metapenaeus intermedius, 3.1 to 1, Charybdis bimaculata and 6.1 to 1, Squilla oratoria. The microscope finding of the purified chitin showed the filamentous form in all the specimen.

• Journal of Korean Society of Forest Science
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• v.32 no.1
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• pp.29-35
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• 1976

In order to estimate sawmill productivities, rates of technical change and optimum combination of production factors, Cobb-Douglas production functions have been derived using data obtained from 96 sample mills in Busan-Incheon, southwestern and northeastern areas. The results may be summarized as follows: 1. There is a tendency of expanding average sawmill size in the areas. The horse-power holdings per mill have been increased at the rates of 91 percent in Busan-Incheon, 7.7 percent in southwestern and 16.9 percent in northeastern areas. This implies that the mills around log-importing ports have made rapid development, compared with those in forest regions. 2. The regression coefficients (production elasticities) of the functions for the year of 1967 in the above three areas are much similar each other, but significant differencies are found in the production functions of 1975. In other words, sawmill productivity was mainly restricted by capital deficiencies in all areas in 1967, but this situation was succeeded only by N-E area in 1975. The range of sum of regression coefficients is 1.0437-1.4214, this indicates increasing rates of return to scale. 3. The annual rates of technical changes in B-I, S-W and N-E areas for the observed period are 17.6, 7.6 and 2.2 percents respectively. Busan-Incheon is the only area where labor productivity is higher than that of capital. 4. The best combination of production factors for maximizing firm's profit is subject to the changes of input and output prices. With some assumptions of prices and costs, the optimum levels of power and labor input in B-I, S-W and N-E areas are 57:17, 427:94 and 192:27.

• Journal of Korean Home Economics Education Association
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• v.19 no.4
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• pp.91-117
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• 2007

This study was to compare the contents and practical problems addressed, the process of teaching-learning method, and evaluation method of Korean Home Economics curriculum and of the Oregon and Ohio's Practical Problem Focused Family & Consumer Sciences Curricula. The results are as follows. First, contents of Korean curriculum are organized by major sub-concepts of Home Economics academic discipline whereas curricular of both Oregon and Ohio states are organized by practical problems. Oregon uses the practical problems which integrate multi-subjects and Ohio uses ones which are good for the contents of the module by integrating concerns or interests which are lower or detailed level (related interests). Since it differentiates interest and module and used them based on the basic concept of Family and Consumer Science, Ohio's approach could be easier for Korean teachers and students to adopt. Second, the teaching-learning process in Korean home economics classroom is mostly teacher-centered which hinders students to develop higher order thinking skills. It is recommended to use student-centered learning activities. State of Oregon and Ohio's teaching-learning process brings up the ability of problem-solving by letting students clearly analyze practical problems proposed, solve problems by themselves through group discussions and various activities, and apply what they learn to other problems. Third, Korean evaluation system is heavily rely on summative evaluation such as written tests. It is highly recommended to facilitate various performance assessment tools. Since state of Oregon and Ohio both use practical problems, they evaluate students mainly based on their activity rather than written tests. The tools for evaluation include project documents, reports of learning activity, self-evaluation, evaluation of discussion activity, peer evaluation in a group for each students for their performance, assessment about module, and written tests as well.

• KSBB Journal
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• v.24 no.4
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• pp.377-382
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• 2009

The culture condition of growing Chlorella minutissima was optimized to produce biodiesel for fed-batch cultivation. First, under heterotrophic cultivation, the optimum level of glucose was determined to be 10 g/L for 20 days. After, three cultivation conditions were operated: autotrophic, heterotrophic, and mixotrophic growth. The lipid level and the maximum cell concentration from the fed-batch heterotrophic process were 32.0 (%, v/v) and 15.0 (g-dry wt./L) in 20 L flask, respectively. In addition, since the relatively constant specific lipid production rate was observed as 0.040 (% lipid/g-dry wt./day) at the latter period of cultivation time, the fed-batch process could maintain continuous lipid production. Fed-batch process is higher than those values from the batch process. The lipids from the fed-batch process contained over 38% of $C_{18}$, known as the suitable composition for the biodiesel application. For mixotrophic and heterotrophic growth under fed-batch condition, glucose was proved to be an appropriate carbon source for a large scale outdoor cultivation. For fed-batch cultivation, the feeding rate of seawater medium containing glucose was decided to be 0.5 L/day. The mixotrophic cultivation maintained maximum cell concentration of 24 (g-dry wt./L) and the lipid level of 43 (%, w/w). The lipid composition from this process was also proved to be suitable for the biodiesel production. The fatty acids from the mixotrophic growth contains 18% of $C_{17}$ and 49% of $C_{18}$, implying It also tells that C. minutissima is a suitable resource of biodiesel. Especially, the mixotrophic cultivation with fed-batch process might be useful for the large scale cultivation for the biodiesel production.

• Korean Journal of Environment and Ecology
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• v.15 no.4
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• pp.361-368
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• 2002

The valley forests located at the east-facing slope and the west facing slope in Hambaeksan area were studied to investigate forest structure in relation to aspect and altitude of the slope. There was little difference in density. mean DBH and basal area of the tree layer between east-facing slope and west-facing slope. The importance percentages of Tilia amurensis and Betula costata in west-facing slope were higher than those in east-facing slope. However, the importance percentages of Quercus mongilica and Fraxinus rhynchophylla in the west facing slope were lower than those in east-facing slope. Species diversity of the west-facing slope was 1.415 and that of the east-facing slope was 1.328. Elevation trends were also found for forest structure. As elevation Increased basal area and mean height of the tree layer decreased in both of east-facing slope and west-facing slope. There was a tendency that number of species, species diversity and evenness decreased with increasing elevation. The importance percentage of Quercus mongolica increased with increasing elevation while those of Betula costata and Maackia amurensis decreased. The result of cluster analysis for the tree and subtree layer indicated that the studied forests were classified into the mixed forest community of broad-leaved tree species at west-facing slope and the low and middle elevation belts of east-facing slope and Quercus mongolica community at the high elevation belt of east-facing slope. Quercus mongolica was significantly and positively correlated with Symplocos chinensis for. pilosa, Acer tschonoskii var. rubripes and deutzia glabrata. Betula costata was significantly and negatively correlated with Quercus mongolica and Acer pseudo-sieboldianum.

• Progress in Medical Physics
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• v.17 no.1
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• pp.1-5
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• 2006

A parallel plate detector containing PTFE films in FEP film for relative dosimetry was designed to measure the response of detectors to S and 10 MV X-rays from a medical linear accelerator through different thicknesses of lead. The dielectric materials were 100 m thick. The set-up conditions for measurements with this detector were as follows: SSD=100 cm the test detector was at a depth of 5 cm and the reference chamber was at a depth of 10 cm from the phantom surface for 6 and 10 MV X-rays. Lead blocks were designed to cover the irradiated field. They were added to the tray to increase thickness sequentially. We found that the detector response decreased exponentially with the thickness of lead added. The linear attenuation coefficients of the test detector and reference chamber were 0.1414 and 0.541, respectively, for 6 MV X-rays and 0.1358 and 0.5279 for 10 MV X-rays. The test detector response was greater than that of the reference chamber. The response function was calculated from the measured values of the test detector and reference chamber using optimization. These optimized constants for the detector response function were independent of theenergy. As a result of optimizing the response function between detectors, the use of a relative dosimeter was validated, because the response of the test detector was 1% for 6 MV X-rays and 4% for 10 MV X-rays.

• Journal of Korean Academy of Nursing
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• v.3 no.2
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• pp.121-132
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• 1973

Introduction : Nursing as a profession is gelling wide acceptance today, especially among independent -minded women with necessary physical, mental and academic qualifications. This is particularly true of "comprehensive nursing", which requires to total dedication on the part if the nurse herself-physical, mental and sociocultural. Such comprehensive approach is like-wise called for in the institutional training of professional nurses. Undergraduate nursing courses nowadays place an increasing emphasis on the microscopic approach of training a nurse as an intelligent and well-balanced human being with an optimum degree of cultural sophistication. Greater attention then ever before is now paid to close observation of the individual traits and aptitude of nursing students, so as to permit full development of individual capabilities, interests and propensities within the concept of "comprehensive human education. " Purpose of study 1. To determine the degree of understanding of the part of nursing students of the various aspects of the subject taught in undergraduate nursing course. 2. To determine the motivation of nursing students in choosing the profession and possible subsequent change or attitude and outlook in the course of under graduated studies, as a means of presenting a new practical approach in nursing training based on the concept of "comprehensive human education. " Problems of study 1. The environments of nursing training will impinge on individual nursing students with different psychological impacts from lower to upper classes of under graduated studies. 2. Educational environments will have varying psychological impacts on students: a. Difference in religious faith among students. b. Difference in campus environments. c. Difference in domestic (family) circumstances. d. Difference in innate capabilities of students, 3. The understanding and attitude of individual nursing students towards the science of nursing will Have a close correlation with their respective motivations in choosing-nursing as a profession, and will also be closely influenced by the peculiarities of the subject taught, tile campus environments, etc, Delimitations of the study 1. Two universities offering 4-year nursing courses were selected. Due to the limited number of potential subjects, the optimum conditions of sample collection could not be fulfilled. 2. Subjects were confined to two classes in each university (sophomores and seniors) but without regard to the ages or scholastic achievements of individual students. 3. The conclusions derived from this study should be limited in application to the subject groups covered by the present study: they should not in any event be extended or applied to other groups. Procedures 1. Subjects: 40 nursing students each from the sophomore and senior classes of the "Y" and "K" universities situated in Seoul, aggregating 160 students altogether. 2. Instruments: Use has been made of questionnaires on (1) family backgrounds and (2) general information concerning. 3. Statistical Method: The findings of the present survey have been subjected to critical analysis as to the means, percentages, Cgi squares (X), standard deviations and the significance of the difference in means. Findings 1. Nursing students have chosen their subject of study with a confident outlook towards their future in society. 2. Horsing students have the necessary abilities to complete the prescribed courses of study. 3. The campus life of nursing students has been judged as very constructive, not with-standing certain in adequacies in the available educational facilities and the shortages of teaching staff. 4. The achievement levels of nursing trainees varied greatly according to their respective educational environments as well as their school years. 5. Clear and definite distinctions were discernible between the two universities as regards certain aspects of this survey, while no signifiant difference was observed in other: a. Sophomores and seniors in both universities gave nearly identical answers to questions concerning (1) motivation in choosing nursing as a profession, and (2) the way of spending leisure hours. b. Both universities revealed similar respective differences between sophomores and seniors as regards the abilities of fulfilling academic requirements ill the basic subjects. c. Educational environments have been found to be somewhat superior in the "Y"university to those of the "K" university, particularly as regard general campus and dormitory conditions. d. The high degree of dissatisfaction with the faculty, found in both universities, was considered to be a consequence of the universal phenomenon of "brain drain" and the relative neglect of the "comprehensive approach"in education.

• Journal of Oral Medicine and Pain
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• v.30 no.1
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• pp.57-67
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• 2005

The aim of this study was to evaluate bone scan(SUR) and SPECT(hot spot) in patients with TMJ osteoarthritis. 99mTc-MDP bone scan and SPECT were done in 27 patients, total 54 temporomandibular joints were examined with clinical examination, plain radiography. 42 TMJs were osteoarthritis and 12 TMJs were normal case, clinically diagnosed. We compared osteoarthritis group and control group of bone scan(SUR) and SPECT(hot spot). thus we compared before and after treatment of bone scan(SUR) and bone SPECT(hot spot) according to history, contributing factor, symptom degree, treatment, treatment period. The obtained results were as follows. 1. Bone scan(SUR) and SPECT(hot spot) activity of osteoarthritis group were higher than control group(P<0.05, P<0.01). 2. Bone scan(SUR) and SPECT(hot spot) activity were decreased after treatment at TMJ with osteoarthritis(P<0.01). 3. Bone scan(SUR) and SPECT(hot spot) activity were decreased at treatment group with splint(P<0.01, P<0.05). 4. Bone scan(SUR) and SPECT(hot spot) activity were decreased at Chronic group(P<0.01, P<0.05). 5. Bone scan(SUR) and SPECT(hot spot) activity were decreased at low noise NAS(<6) group(P<0.01,P<0.05). 6. Bone scan(SUR) and SPECT(hot spot) activity were decreased at TMD patient with parafunctional habit and without trauma history, psychosocial factor. 7. Bone scan(SUR) and SPECT(hot spot) activity were higher at before treatment required more treatment period.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.319-324
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• 2014

The aim of this study was to evaluate influences of titanium dioxide ($TiO_2$) concentrations and irradiation times on growth of Streptococcus mutans when irradiated by visible light (405 nm wavelength) and by ultraviolet light (254 nm wavelength). To find the optimal antibacterial concentration of $TiO_2$, 0.01, 0.1, 1.0, and 10.0 mg/ml $TiO_2$ suspension was prepared with sterilized distilled water. S. mutans cultured media was added to $TiO_2$ solution to set the final cell count to $10^4CFU/ml$. The photocatalytic reaction was induced by irradiating 254 nm and 405 nm lights for 10 minutes. To compare the bactericidal activities according to irradiation times, all photocatalytic reaction was carried out with 0.1 mg/ml $TiO_2$ for 0, 10, 20, 30, and 40 minutes with both lights. After the photocatalytic reaction, $100{\mu}m$ of the reaction mixture was immediately plated on brain heart infusion agar. These plates were placed at 5% $CO_2$, $37^{\circ}C$, for 24 hours and the bacterial colonies were counted. All experiments were performed in quintuplicate. One-way ANOVA was used to determine whether there were any significant differences between the $TiO_2$ concentrations or the irradiation times. The most effective concentration of $TiO_2$ for its photocatalytic bactericidal effect on S. mutans was 0.1 mg/ml when irradiated with 254 nm and 405 nm lights. The longer the irradiation time, the bigger the bactericidal effect for both wavelengths. Over 99% of bacteria in the inoculum were killed after irradiation with 254 nm for 20 minutes and with 405 nm for 40 minutes. In conclusion, a photocatalytic reaction of $TiO_2$ induced by visible light of 405 nm constitutes the bactericidal effect on S. mutans.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.125-130
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• 1975

This investigation was carried out to define the cultivation state of Ginseng seedling and to study the growth of important characters by location and correlations between characters, the results obtained are summarized as follows; 1. Most of farmers culitvating ginseng seedling had not any special consideration for the improvement of soil, and they applied green manure only as basic fertilizer but they did not apply chemical fertilizer. 2. Any efforts on the improvement of ginseng seed were not found. Seed was harvested from 3 years old ginseng plant. Seedling density was 1.8 cm by 2 cm. 3. Growth of all characters showed significant differences among farms. Coefficients of variation among individual seedling plants was largest at root diameter and smallest at root length. 4. Gromth of all characters without root diameter by planted location under the shadow was poor at front row, however root diameter was shortest at back row. 5. Significant high correlatons were rocognized between root diameter and stem diameter, between leaf blade and stem diameter and between leaf blade and leaf length, but stem length were not correlated with any characters. It is noticable that negative correlations were found between stem length and root diameter, between stem length and root length and between stem length and stem diameter.