• Journal of Bio-Environment Control
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• v.4 no.2
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• pp.181-187
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• 1995

This study was conducted to investigate the effect of NH$_4$H$_2$PO$_4$ on pH of the nutrient solution using municipal tap water during hydroponic culture of crisp lettuce (Lactuca sativa var. capitata) seedlings. The composition of starter solution was different from that of supplementary solution. The pH in the nutrient solution was suddenly declined and recovered as the supplementary solution was supplied. The pH of nutrient solution was increased with high temperature and, on the contrary, the EC of nutrient solution was decreased. It shows that plant absorbed nutrients more than water in given solution when the temperature and light was high. After supplying supplementary solution in 1st and End experiment, pH was slowly increased to 7 in NH$_4$H$_2$PO$_4$ 0.25me/$\ell$, but maintained 6.4-6.5 in NH$_4$H$_2$PO$_4$ 3me/$\ell$ and 6me/$\ell$. In 3rd experiment, pH was slowly increased from 6.7 to 7.4 in NH$_4$H$_2$PO$_4$ 0.25me/$\ell$, but decreased from 6-6.5 to 5-5.5 in NH$_4$H$_2$PO$_4$ 3me/$\ell$ and 6me/$\ell$. So it is suggested that the concentration between 0.25 me/$\ell$ and 3 me/$\ell$ by concentration base or the amount of NH$_4$H$_2$PO$_4$ between 1me/6 $\ell$ and 7me/6 $\ell$ by total quantity in solution is appropriate for stabilizing pH in the nutrient solution. Also this experiment suggests that hand operated measurements must be cautious due to the change of pH and EC within a 24-hour cycle.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.282-293
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• 2008

In order to develop the substitutive materials for natural baits of swimming crab pots, the attracting effects of swimming crab such as the preference of baits which were made of the by-products of marine and stock raising through the water tank experiments and fishing experiments. On the investigation of mean entrapped catch number to the pot by the baits after putting the 4 kinds of baits, mackerel(M), mackerel with grinded mackerel s internals($MM_I$), mackerel with tuna s internals$MM_I$) and makerel with grinded krill(MK) each in one pot by turns, $MM_I$ and MK were entrapped mean 3.9(13.0%) and they were a little more comparing to M, and $MT_I$ is least with mean 2.1(7.0%)(F=12.913, P < 0.05). Otherwise, on the preference investigation of swimming crabs by the baits after putting the 4 kinds of baits in the 4 pots each, M was entrapped mean 3.0(10%), but $MM_I$, $MT_I$ and MK were mean 1.2(4.0%), 1.0(3.3%) and 1.5(5.0%) each and they were only 30-50% of M(F=13.398, P < 0.05). On the preference investigation of swimming crabs by the 5 kinds of baits, mackerel(M), and krill(K), manila clam($M_C$), pig s fat($P_F$) and chicken s head($C_H$) which were used in substitutive baits, M was entrapped mean 3.2(10.7%), but K was about 50% of catch of M with mean 1.6(5.3%), and $M_C$, $P_F$ and $C_H$ were very few with mean 0.1-0.2(0.3-0.7%)(F=89.186, P < 0.05). On the preference investigation of swimming crabs by the pots which were put each the 3 kinds of baits, original krill(K), grinded krill with gluten and soybean oil cake($K_GGS$) and grinded krill with gluten, soybean oil cake and glycine($K_GGSG_L$) in the blue fluorescent hexahedral plastic bait cages(BF), and which were put the mackerel(M) in the non-fluorescent hexahedral red plastic bait cage($RF_N$), it was entrapped mean 3.0(10.0%) in the pot which was put the mackerel in the $RF_N$, and the same level in the pots which were put the K and $K_GGSG_L$ in the BF, but it was mean 2.0(6.7%) in the pots which was put the $K_GGS$ in BF and it was decreased by 30% of catch comparing to $RF_N$(F=3.750, P < 0.05). On the preference investigation of swimming crab by the pots which was put grinded tuna with gluten, soybean oil cake and glycine($T_IGSG_L$) in the blue fluorescent hexahedral plastic bait cage(BF), and which was put mackerel(M) in the nonfluorescent hexahedral red plastic bait cage($RF_N$), it was entrapped mean 3.3(11.0%) in the pot which was put mackerel in $RF_N$, and mean 2.7(9.0%) in the pot which was put $T_IGSG_L$ in BF and it was about 15% less comparing to use bait M(t=1.387, P < 0.05). As a results of fishing experiments, a plan for enhancing catching efficiency of $T_IGSG_L$ will be required because catching efficiency of $T_IGSG_L$, alternative bait, was half of fish catching efficiency of natural bait using mackerel. Fishing experiments were conducted 3 times using reinforced substitutive artificial bait that is reinforced attractive effect of $T_IGSG_L$ and composed of tuna intestine, grinded mackerel, gluten, soybean cake, glycine and alanine($T_IM_GGSG_LA$). Catching efficiency of $T_IM_GGSG_LA$ was about 80% of that of natural bait made of mackerel.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.6-15
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• 1973

In an attempt to develop composite flours based on raw materials available in Korea, six domestic resources were investigated with respect to their physical and chemical properties, nutritive value and economy. The results are summarized as follows: 1) Flours from naked barley, sweet potato, potato, corn, defatted rice bran and defatted soybean were compared in respect of their proximate composition, thiamine content and protein score. 2) In color comparison, naked barley and defatted soy flours were comparable to wheat flour whereas corn and sweet potato flours were a little inferior. In raising power, naked barley and defatted soy flours were similar to wheat flour and others were inferior. 3) In maximum viscosity of flours by amylograph, naked barley, corn and potato flours were higher than wheat flour and others were lower. In viscosity in cooling, corn flour was similar to wheat flour and naked barley and potato flours were lower. Addition of $10{\sim}20%$ defatted soy flour into other flours generally caused the lowering of viscosity. Addition of emulsifiers such as glyceryl monostearate, calcium stearyl lactylate, Methocel and Emulthin into the flours manifested different effects on the amylogram. 4) In nutritional test by rat, diets consisting of naked barley, sweet potato, potato or corn flours, each containing defatted soy flour (at 10% level with exception of 20% for sweet potato flour) and naked barley flour fortified with lysine were similar to wheat flour in digestibility, but were superior in NPU and biological value. 5) In price estimation, sweet potato and corn flours were competitive with wheat flour, but naked barley flour was a little expensive. On the other hand, barley and sweet potato are promising in terms of domestic production.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.242-253
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• 1998

South Korea has been producing asbestos over 60 years. The use of asbestos was over 50 years for production of asbestos slate and 27 years for asbestos friction materials including asbestos textile and brake-lining. Thus, it can be supposed that asbestos related diseases such as asbestosis, lung cancer and mesothelioma could be found in the vulnerable workers exposed to asbestos in 1955-1975, given the average latency period of 10-30 years. Asbestos was produced primarily by Japanese during World War II In Korea. The production of chrysotile peaked to 4,815 tons in 1944. From 1978 to 1984, 10,000 tons of asbestos were produced annually. However, the production was interrupted by raising labor costs and extinction of mine reserves, and finally they had to depend on import for the need of asbestos. In 1945, there were 16 asbestos mines, in total, with the addition of new asbestos mines in South Korea. Imports of asbestos was increased from 74,000 tons to 95,000 tons during the period of 1976 - 1992. But the imports was reduced to 88,000 tons in 1995. Since, in addition to the import of asbestos itself, the imports of asbestos products were increased as well and the accumulation of asbestos reached to 30,000 tons during the period of 1964 to 1993. In 1965, there was only one asbestos company with 207 employees. But the size of asbestos industry has been expanded so much that 118 asbestos companies could be found in 1993 with 1,476 workers. However, there was no record on the survey of asbestos concentration to which workers were exposed in any companies in 1983. The record of the air-borne concentration of the asbestos in textile working places in 1984 showed 6.7 fibers/cc by geometric mean(GM), but it was reduced to 1.2 fibers/cc in 1993. GMs of asbestos in working places for construction materials and asbestos textiles were also decreased from 1.7 fibers/cc to 0.55 fibers/cc during the period of 1984 - 1996.

• Korean Security Journal
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• no.10
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• pp.355-385
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• 2005

As the system of autonomous police that has been debated for long time is fixed to be introduced by the program of participatory government, this treatise intends to analyze main contents and review controversial items in order to present supplementary measures. The program of participatory government to introduce autonomous police in Korea focuses on converting the autonomous police of Korea from centralized police administration in order to provide 'customized security service' that is appropriate to the regional environment. Thus, if relevant city, county or district considers that it is required to introduce the system autonomous police, the assembly may enforce the decision by enacting ordinance. For enforcement, organization in the unit of section will be established in the line of mayor, county headman and district office. The main role will be security service that is closely related to the life of inhabitants such as crime prevention, patrol, traffic crackdown, etc. as well as public health, sanitation and environmental control which are being performed by autonomous organization at present. However some expected controversial items may be summarized in the following 3 points on the premise of accepting the program of government. First, the point at issue related to the basic function of police. The basic function of police is generally understood as order keeping function such as anterior and preventive job and law enforcing function such as posterior and suppressing job. By the way, the program of government does not endow the autonomous police with investigation right for general crime, thereby raising the controversy that our autonomous police is nothing but the assistant of police. Furthermore, the present national police also expresses its dissatisfaction to the transfer of authority. Second, the issue of balance of security service between self-governing bodies may be raised. The security environment is different between self-governing bodies and thus demand of security is different. Therefore, the security service of autonomous police will reveal difference in qualitative aspect for each self-governing body. Moreover, it can be easily anticipated that the quality of security service may be different as per the financial independence degree. Third, the point at issue anticipated with the operation funded by the budget of self-governing body. As autonomous police is operated by the budget of self-governing body, the following problems may be raised; (1) since police administration is subordinated to general administration, the concentration may be weakened (2) the cooperation between policy agencies may be impeded (3) owing to the difficult in possessing spare police, the mobility of police may be somewhat reduced.

• Korean Journal of Applied Biomechanics
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• v.15 no.2
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• pp.11-20
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• 2005

This study has a purpose on contributing to apprehend safe and right way to stop to the inline skate beginners and to the instructors who teaches line skating on the basis for the result of the kinematical analysis on Heel brake stop movement of the inline skate, focusing on the displacement on COG, angle displacement of ankle joint, angle displacement of knee joint, angle displacement of hip joint, using a 3D image method by DLT. To achieve this goal, we analysed the kinematical factor of the 3 well-trained inline skating instructors and obtained the following results. 1. During the movement of heel-brake stop, when strong power was given to a stable and balanced stop and the lower limbs, if the physical centroid is lowered the stability increases, and if it is placed high from the base surface, as the stability decreases compared to the case of low physical centroid, we should make a stop by placing a physical centroid in the base surface and lowering the hight of physical centroid. 2. To make a stable and balanced stop and to provide a strong power to the lower limbs, it is advisable to make a stop by decreasing an angle displacement of ankle joint during a "down" movement. In case of the left ankle joint, in all events and phases the dorsiflexion angle showed a decrease. Nevertheless, in the case of the right ankle joint, the dorsiflexion angle shows an increase after a slight decrease. The dorsiflexion angle displacement of ankle joint can be diminished because of the brake pad of the rear axis frame of the right side inline skate by raising a toe, but cannot be more decreased if certain degree of an angle is made by a brake pad touching a ground surface. To provide a power to a brake pad, it is recommended to place a power by lowering a posture making the dorsiflexion angle of the left ankle joint relatively smaller than that of the right ankle. 3. To make a stable and balanced stop and to add a power to a brake pad, the power must be given to the lower limbs in lowering the hight of physical centroid. For this, it is recommended to make a down movement by decreasing the flexion angle of a knee joint and it is necessary to make a down movement by a regular decrease of the angle displacement of knee joint rather than a swift down movement in every event and phase. 4. The right angle displacement of hip joint is made by lowering vertically the hight of physical centroid as leaning slightly forward. If too narrow angle displacement of hip joint is made by leaning forward too much, the balance is lost during the stop by placing the center in front. To make a stable and balance stop and to place a strong power to the lower limbs, it is recommendable to make a narrow angle by lower the hip joint angle. However, excessive leaning of the upper body to make the angle too narrow, can cause an instable stop and loss of physical centroid. After this study, it is considered to assist the kinematical understanding during the heel brake stop movement of the inline skate, and, to present basic data in learning a method of stable and balanced stop for the inline skating beginners or for the inline skate instructors in the present situation of the complete absence of the study in inline skating.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.579-585
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• 2014

This study was conducted to investigate liquid pig manure (LPM) application rates on the growth characteristics, yield, and feed value of whole crop barley in Yeongsangang and Saemangeum reclaimed tidal land. Electronic conductivity (EC), organic matter (OM), and available phosphate (Av. $P_2O_5$) increased in chemical properties of Yeongsangang and Saemangeum soil as raising LPM application level. As increasing LPM application level, exchangeable $Na^+$ significantly increased in Yeongsangang, while exchangeable $K^+$ significantly increased in Saemangeum. Plant height was not significantly different from LPM 100% to LPM 200% in Yeongsangang and in Saemangeum. Dry matter yield of whole crop barley increased steadily, but crop yield of LPM 200% in Yeongsangang ($10.5ton\;ha^{-1}$) was as much as that of LPM 150% ($10.0ton\;ha^{-1}$). Yield of LPM 200% ($11.2ton\;ha^{-1}$) in Saemangeum was similar to that of LPM 150% ($10.5ton\;ha^{-1}$). Crude protein (CP) increased depending on LPM application level, but total digestible nutrients (TDN) increased regardless of LPM application level. LPM 200% was the highest in TDN yield (Yeongsangang: $7.4ton\;ha^{-1}$, Saemangeum: $6.9ton\;ha^{-1}$), but there was no statistical difference between LPM 150% (Yeongsangang: $6.9ton\;ha^{-1}$, Saemangeum: $6.6ton\;ha^{-1}$) and LPM 200%. From the results described above, optimum rate of LPM for cultivating whole crop barley is considered 100% in Yeongsangang reclaimed tidal land and 150% in Saemangeum reclaimed tidal land, showing that the effect of LPM application is better in Segmentation than that in Yeongsangang for yield of whole crop barley.

• Journal of the Korean Wood Science and Technology
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• v.17 no.2
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• pp.34-64
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• 1989

Corner block with anchor bolt(CBA) joint method used in knock-down type table furniture manufacturing can reduce the packing and transporting cost. Unfortunately. it also has the disastrous defect to be loosend and unstable during the service life mainly due to fatigue and creep(repeated and prolonged loading). So 22 joint groups constructed were tested to evaluate the effect of some design factors related to the size of side rail(apron). block attachment to side rail. and the number of anchor bolt as well as the effect of the type of corner block(mitered type vs. rectangular type) Usable strength from the stiffness coefficients of each joint group were analysed with SPSS /PC+ and described as the criteria of CBA joint construction. The conclusions were as follows: The height of side rail(50, 75 and 100 mm) and the addition of polyvinyl acetate(PVAc) emulsion in the corner block attactment to side rail had the effect on raising the usable strength of CBA joint with remarkable high significance. And the effect of 2 - anchor bolts was also superior to that of 1 - bolt significantly. However. the thickness of side rail(22 mm vs. 25 mm) had no effect on the strengthening the table joint rigidity. Mitered type corner block joint appeared to he recommendable for CBA jointed table construction rather than the rectangular type one regardless of the method of block attachment to side rail. The best result identified from Duncan's multiple comparison was in the construction with 25 mm thick and 100 mm height of side rail fastened using 2 - anchor bolts in mitered type corner block. But it would be reasonable to use 22 mm thick & 75 mm high side rail and mitered corner block with PVAc emulsion & 2 bolts considering the productivity and production cost down in the MDF furniture manufacturing industries.

• Information Systems Review
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• v.12 no.3
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• pp.19-48
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• 2010

This study focused on characterizing various factors in order for learners to maintain their interests in learning and to maximize learning effects as the top priority purpose of university e-Learning, on the basis of results of conceptual studies on existing e-Learning and practical studies, and then on examining them practically. It also analyzed which factors would have greater influence on learning effects of e-Learning in general. Moreover, in comparison with existing numerous studies which examined only factor such as learning effects of e-Learning, it analyzed such things in detail according to division into three items such as learning satisfaction, learning transfer and learning recommendation. To achieve such purposes of the study, it characterized and set 3 factors such as learning contents, instructional design and user convenience on the assumption that such factors have a significant influence on learning effects of e-Learning. Moreover, the factor of learning contents includes 3 detailed elements, i.e., learning issue and objective, knowledge information, and consistency and propriety, and the factor of instructional design includes 4 detailed elements, i.e., interest and sympathy, interaction, contents presentation and explanatory strategy. Lastly, the factor of user convenience includes 2 detailed elements such as screen configuration, and check-up of contents and teaching schedule. According to analytical results, it showed all 3 factors such as learning contents, instructional design and user convenience have a significant influence on learning effects of e-Learning(i.e., learning satisfaction, learning transfer and learning recommendation). In more detail, it showed the learning issue and objective from the factor of learning contents have the greatest influence on learning satisfaction of e-Learning. Then, it is the most important to set the learning issue and objective with given priority to learners and set the learning objective estimable, in order to raise the learning satisfaction. It showed the contents presentation from the factor of instructional design on the learning transfer. Therefore, it is the most important to structuralize mutual relation and presentation orders to promote learning systematically and to let learners access to such things, for the purpose of raising the learning transfer. Moreover, it showed the interest and sympathy from the factor of instructional design has the greatest influence on the learning recommendation. Thus, it is the most important to promote learners' interests to the maximum using well-timed media, and to give a lecture enough to arouse learners' sympathy.

• Research in Community and Public Health Nursing
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• v.7 no.2
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• pp.294-312
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• 1996

Relatively young widows, who are left with young children by a sudden death of their husbands, will be faced with not only psychological troubles such as individual anxiety and frustration but also the dual burden of playing both father and mother roles in a family, Also, family members have difficulty in adapting themselves to new circumstances of the family system, the training and raising of family members, and management of the family economy. In this study, the realistic resources on the experience of middle-aged women who are bereaved of their husbands by accidents were explored. The purpose of this study is to help widows adapt to life in society and live a more positive life by setting a new goals and recovering from a lost and twisted life. 11 women, who have experienced the loss their husbands and live in the Seoul metropolitan area were studied. The research took 116 days from December 15, 1995 to April 8, 1996. The method of research was direct interviews. While having interviews with them, the contents were recorded with their consent. The ground theory was that used by Strauss & Corbin(1990) in the analysis of the data. 81 concepts were analyzed and they were subdirided into 22 subordinate categories through the course of the analysis. These were then classified into 9 general categories. In the course of being categorized, 'absurdity' was showed as a core category. The subordinate categories 'surprise', 'gloom', 'grudge', 'helplessness', 'emptiness', and 'loss' were united in the core category 'absurdity'. Ominous presentiment, belated notice, death, surprise, gloom, grudge, helplessness, emptiness, loss, the situation of the children, lack of support from neighbors, support from neighbors, mulling over ways to live, choosing a job, strengthening, reinforcement, burden, sadness, smoldering, yearning, overcoming these 22 subordinate categories were re-composed into 9 general ones the husband's death, absurdity, presence of children, existence of support, self-support ability, preparation of countermeasures, self-reinforcement, toilsomeness, and overcoming. 'Absurdity' widows experience was shown in the results of 'toilsomeness' and 'overcoming' through reaction, confrontation, and adaptation. According to the analysis the central phenomenon was absurdity, the causal condition of the death of a husband, the presence of children and the existence of support, and the meditated situation of self-support. To solve absurdity, the preparation of countermeasures and self-reinforcements were shown resulting in toilsomeness and overcoming. Through the contrast in the data, the following statements were deduced: (1) If the death of the husband is expected, the more a widow will feel absurdity. (2) The more children she has and the younger she is, the more a widow will feel absurdity. (3) The lower support she is given, the more a widow will feel absurdity. (4) The larger self-ability she has, the more actively she will prepare countermeasures. (5) The smaller self-ability she has, the more passively she will prepare countermeasures. (6) The larger self-ability she has, the weaker self-reinforcement she will preform. (7) The smaller self-ability she has, the stronger self-reinforcement she will perform. (8) The more actively she prepares countermeasures for absurdity, the better she will overcome. (9) The more passively she prepares counter measure for absurdity, the worse she will overcome. (10) The stronger self-reinforcement for absurdity she performs, the better she will overcome. (11) The weaker self-reinforcement for absurdity she performs, the worse she will overcome. Through the results in this study, the following suggested: 1) A study whose object is all family members, and a comparative study on the case of a husband who has lost his wife should be done. These studies can be expected to develop a more refined theory. 2) Because of the collapse of the extended family system and the changes of family culture in Korea, a widow's status and position are apt to be ambiguous between her husband's home and her parent's. Therefore a new study on family culture should be made. 3) A continuous study on growing social Self Help Groups should be requested for the widows of this study to re-establish and recover from their twisted and scattered lives.