• The Journal of Fisheries Business Administration
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• v.15 no.1
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• pp.131-153
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• 1984

Fishery resources are still abundant compared with other resources and the possibility of exploitation is probably great. The Korean fishery industry has grown remarkably since 1957, and Korea is ranked as one of the major fishery countries. Its of fishery products reached the 9th in the world and the value of exports was 5th in 1982. But recently a growth rate has slowed down, due to the enlargement of territorial seas by the declaration of the 200 mile, Exclusive Economic Zone, the tendency to develop fishery resources strate-gically in international bargaining, the change in function of the international organizations, the expansion of regulated waters, the illegal arrest of our fishing boats, the rapid rise in oil prices, and the fall in fish prices, the development of fishery resources as a symbol of nationalism, the fishing boats decreptitude, the rise of crew wages, regulations on fishing methods, fish species, fishing season, size of fish, and mesh size, fishing quotas and the demand of excessive fishing royalties. Besides the the obligation of coastal countries, employing crews of their host countries is also an example of the change in the international environment which causes the aggravation of foreign profit of fishing firms. To ameliorate the situation, our Korean fishery firms must prepare efficient plans and study systematically to internationalize themselves because such existing methods as conventional fishing entry and licence fishing entry are likely to be unable to cope with international environmental change. Thus, after the systematic analysis of the problem, some new combined alternatives might be proposed. These are some of the new schemes to support this plan showing the orientation of our national policy: 1. Most of the coastal states, to cope with rapid international environmental change and to survive in the new era of ocean order, have rationalized their higher governmental structure concerning the fishery industries. And the coastal countries which are the objectives of our expecting entry, demand excessive economic and technical aid, limit the number of fishing boats’entry and the use of our foreign fishing bases, and regulate the membership of the international fishery commissions. Especially, most of the coastal or island countries are recently independent states, which are poorer in national budget, depend largely on fishing royalties and licence entry fees as their main resources of national finance. 2. Alternatives to our entry to deep sea fishing, as internationalization strategies, are by direct foreign investment method. About 30 firms have already invested approximately US $ 8 million in 9 coastal countries. Areas of investment comprise the southern part of the Atlantic Ocean, the Moroccan sea and five other sea areas. Trawling, tuna purse seining and five other fields are covered by the investment. Joint-venture is the most prominent method of this direct investment. If we consider the number of entry firms, the host countries, the number of seas available and the size of investment, this method of cooperation is perhaps insufficient so far. Our fishery firms suffer from a weakness in international competitive ability, an insufficiency of information, of short funds, incompetency in the market, the unfriendliness of host coastal countries, the incapability of partners in joint-ventures and the political instability of the host countries. To enlarge our foreign fishing grounds, we are to actively adopt the direct investment entry method and to diversity our collaboraboration with partner countries. Consequently, besides proper fishing, we might utilize forward integration strategies, including the processing fied. a. The enterprise emigration method is likely to be successful in Argentina. It includes the development of Argentinian fishing grounds which are still not exploited in spite of abundant resources. Besides, Arentina could also be developed as a base for the exploitation of the krill resources and for further entries into collaboration with other Latin American countries. b. The co-business contract fishing method works in American territorial seas where American fishermen sell their fishery products to our factory ships at sea. This method contributes greatly to obtaining more fishing quotas and in innovation bottom fishing operation. Therefore we may apply this method to other countres to diffuse our foreign fishing entry. c. The new fishing ground development method was begun in 1957 by tuna long-line experimental fishing in the Indian Ocean. It has five fields, trawling, skipjack pole fishing and shrimp trawling, and so on. Recently, Korean fisheries were successful in the development of the Antarctic Ocean krill and tuna purse seining. 3. The acceleration of the internationalization of deep sea fishing; a. Intense information exchange activities and commission participation are likely to be continues as our contributions to the international fishery organizations. We should try to enter international fishery commissions in which we are not so far participating. And we have to reform adequately to meet the changes of the function of the international commissions. With our partner countries, we ought to conclude bilateral fishery agreements, thus enlarging our collaboration. b. Our government should offer economic and technical aids to host countries to facilitate our firms’fishery entry and activities. c. To accelerate technical innovation, our fishery firms must invest greater amount in technical innovation, at the same time be more discriminatory in importing exogeneous fishery technologies. As for fishing methods; expanded use of multi-purpose fishing boats and introduction of automation should be encuraged to prevent seasonal fluctuations in fishery outputs. d. The government should increases financial and tax aid to Korean firms in order to elevate already weak financial structure of Korean fishery firms. e. Finally, the government ought to revise foreign exchange regulations being applied to deep sea fishery firms. Furthermore, dutes levied on foreign purchaed equipments and supplies used by our deep sea fishing boats thould be reduced or exempted. when the fish caught by Korean partner of joint-venture firms is sold at the home port, pusan, import duty should be exempted.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.3
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• pp.25-37
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• 1988

The purpose of this study is to fmd out the bask data for irrigation plans of tomato and chinese cabbage during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration, the maximum evapotranspiration, optimum irrigation point, total readily available moisture and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soji texture for split plot, and three levels, irrigation points with PF 1.8, PF 2.2, PF 2.6 for tomato and those with PF 1.9, PF 2.3, PF 2.7, for Chinese cabbage, soil textures of silty clay, sandy loam and sandy soil for both tomato and Chinese cabbage, with two replications. The results obtained are summarized as follows 1. There was the highest significant correlation between the evapotranspiration and the pan evaporation, beyond all other meteoralogical factors considered. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2. 1/10 probability values of maximum total pan evaporation during growing period for tomato and Chinese cabbage were shown as 355.8 mm and 233.0 mm, respectively, and those of maximum ten day pan evaporation for tomato and Chinese cabbage, 68.0 mm and 43.8 mm, respectively. 3. The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage of growing period for tomato, and at any growth stage till the late of Septemberfor Chinese cabbage. 4. The magnitude of evapotranspiration and of its coefficient for tomato and Chinese cabbage was occurred in the order of pF 1.8>pF 2.2>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7 respectively in aspect of irrigation point and of silty clay>sandy loam>sandy soil in aspect of soil texture. 5. 1/10 probability value of evapotranspiration and its coefficient during the growing period of tomato were shown as 327.3 mm and 0.92 respectively, while those of Chinese cabbage, 261.0 mm and 1.12 respectively. 6. The time that maximum evapotranspiration of tomato can be occurred is at the date of fortieth to fiftieth after transplanting and the time for Chinese cabbage is presumed to he in the late of septemben At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for tomato is presumed to be 74.8 mm and 1.10 respectively, while those of Chinese cabbage, 43.8 mm and 1.00. 7. In aspect of only irrigaton point, the weight of raw tomato and Chinese cabbage were mcreased in the order of pF 2.2>pF 1.8>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7, respectively but optimum irrigation point for tomato and Chinese cabbage, is presumed to be pF 2.6 - 2.7 if nonsignificance of the yield between the different irrigation treatments, economy of water, and reduction in labour of irrigaion are synthetically considered. 8. The soil moisture extraction patterns of tomato and Chinese cabbage have shown that maximum extraction rate exists at 7 cm deep layer at the beginning stage of growth m any soil texture and that extraction rates of 21 cm to 35 cm deep layer are increased as getting closer to the late stage of growth. And especially the extraction rates of 21 cm deep layer and 35 cm deep layer have shown tendency to be more increased in silty clay than in any other soils. 9. As optimum irrigation point is presumed to be pF Z6-2.7, total readily available moisture of tomato in silty clay, sandy loam and sandy sofl becomes to be 19.06 mm, 21.37 mm and 20.91 mm respectively while that of Chinese cabbage, 18.51 mm, 20.27 mm, 21.11 mm respectively. 10. On the basis of optimum irrigation point with pF 2.6 - 2.7 the intervals of irrigation date of tomato and Chinese cabbage at the growth stage of maximum consumptive use become to be three days and five days respectively.

• Journal of Preventive Medicine and Public Health
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• v.2 no.1
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• pp.5-22
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• 1969

The urban population of our country is rapidly increasing due to many factors of social structure, and sociologists are predicting that the increase rate of the urban population will be over 50% in 1980's. Above all, the population of the capital city of Seoul, is at present more than four millions. Such centring of people in cities, together with the improvement of the standards of living, caused rapid increase in the amount of fuel consumption, and this consumption of fuels became one of the primary sources of the air pollution in cities. Moreover, the heavy traffic, construction of many tall buildings, and the increasing number of new factories due to the industrial development-all these are contributing to make the matter of air pollution worse and worse in the Metropolitan, whose geographical location is quite unfavorable considered from the view point of air pollution. Most homes in Seoul use briquet as fuel, while oils are used in tall buildings. The CO, $SO_2$, and smoke that come from burning of these fuels are a great threat to the health of the urban population. With the purpose of examining the influence of air pollution upon the public health, written inquiries were made upon respiratory diseases, and the carboxyhemoglobin saturation in the blood was measured to determine whether the air pollution may affect the health of the urban population. Method of Health Examination (1) Investigation of Respiratory Diseases Patients' records were examined to figure out the monthly ambulance rate of respiratory patients to the total number of patients treated. On the other hand, by using the questionnaire form approved by the Medical Research Council's Committee on Research into Chronic Bronchitis, investigators interviewed the examinees and inquired into the respiratory symptoms. (2) Measuring of Carboxyhemoglobin Saturation From the ear lobe of the examinees, with the use of the melangeur for the white blood cell counting, blood was taken, and after diluting it ten times with 0.1% $Na{2}CO_{3}$, again diulting it 20 times with 0.5% $Na_{2}\;CO_{3}$, its absorbancy was measured. The following results are obtained from the investigation. (1) It was found out that 7.7% of the total patients under treatment were suffering from upper respiratory infection, acute or chronic bronchitis, bronchial asthma, pulmonary emphysema and bronchiectasis. Of them all, patients with upper respiratory infection numbered the greatest with 4.8% and patients with acute or chronic bronchitis the next with 2.1%, and their monthly ambulance rate was high from December to February during the winter, and from April to May and from September to October during the changeable seasons. (2) The daily ambulance rate of respiratory patients, it was revealed, had a close connection with the concentration of $SO_2$ and CO in the air. (3) It was found out that men were more subject to respiratory disease than women, and both men and women were more liable to the diseases with the advancing of age. (4) People living at Choong-ku with the heavy traffic and in the industrial zones of Yeungdungpo had high frequency of respiratory symptoms. (5) Considered from the view point of occupations, high frequency was found among those without job, with jobs unknown, merchants and intdustrial workers, whose social status was rather low and traffic policemen who were always exposed to the exhaust gas of cars. As for women, the frequency was detected in the order of those from high to low, housewives who were exposed to briquet gas, women with jobs unknown, women without jobs, whose social status was low. (6) Ex-smokers rather than smokers, of both sexes, had higher frequency. As for men, heavy smokers had high frequency, while in women light smokers had rather high frequency which was presumed to be due to their average old age. (7) Men's average of carboxyhemoglobin saturation was 9.48%, while women's was 11.3%, higher than men's. (p<0.05). Age meant no difference in the case of men, but as for women, the saturation was remarkably high between the ages from 20 to 60. (8) No regional difference was detected in the carboxyhemoglobin saturation. (9) The carboxyhemoglobin saturation was found, in the case of men, in the order of office workers, traffic policemen, students, the unemployed, merchants and industrial workers, drivers; and as for women, the order was housewives, office workers, merchants and industrial workers. (10) No significant correlation was found between the carboxyhemoglobin saturation and the concentration of CO detected in kitchens, or between the carhoxyhemoglobin saturation and the passing of time after exposure to briquet gas. No difference of carboxyhemoglobin saturation was detected between smokers and non-smokers, and the degrees of smoking; only, significant negative correlation was found between the passing of time after smoking and the carboxyhemoglobin saturation. It is ture that air pollution causes or aggravates the respiratory diseases, increases the carboxyhemoglobin saturation in the blood, but what seems to be more hazardous to the health is the air polluted by the briquet gas in the kitchens and on-dol rooms rather than the atmospheric air pollution.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.60-61
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• 2003

A new approach to reduce the computation time of genetic algorithm (GA) for making binary phase holograms is described. Synthesized holograms having diffraction efficiency of 75.8% and uniformity of 5.8% are proven in computer simulation and experimentally demonstrated. Recently, computer-generated holograms (CGHs) having high diffraction efficiency and flexibility of design have been widely developed in many applications such as optical information processing, optical computing, optical interconnection, etc. Among proposed optimization methods, GA has become popular due to its capability of reaching nearly global. However, there exits a drawback to consider when we use the genetic algorithm. It is the large amount of computation time to construct desired holograms. One of the major reasons that the GA' s operation may be time intensive results from the expense of computing the cost function that must Fourier transform the parameters encoded on the hologram into the fitness value. In trying to remedy this drawback, Artificial Neural Network (ANN) has been put forward, allowing CGHs to be created easily and quickly (1), but the quality of reconstructed images is not high enough to use in applications of high preciseness. For that, we are in attempt to find a new approach of combiningthe good properties and performance of both the GA and ANN to make CGHs of high diffraction efficiency in a short time. The optimization of CGH using the genetic algorithm is merely a process of iteration, including selection, crossover, and mutation operators [2]. It is worth noting that the evaluation of the cost function with the aim of selecting better holograms plays an important role in the implementation of the GA. However, this evaluation process wastes much time for Fourier transforming the encoded parameters on the hologram into the value to be solved. Depending on the speed of computer, this process can even last up to ten minutes. It will be more effective if instead of merely generating random holograms in the initial process, a set of approximately desired holograms is employed. By doing so, the initial population will contain less trial holograms equivalent to the reduction of the computation time of GA's. Accordingly, a hybrid algorithm that utilizes a trained neural network to initiate the GA's procedure is proposed. Consequently, the initial population contains less random holograms and is compensated by approximately desired holograms. Figure 1 is the flowchart of the hybrid algorithm in comparison with the classical GA. The procedure of synthesizing a hologram on computer is divided into two steps. First the simulation of holograms based on ANN method [1] to acquire approximately desired holograms is carried. With a teaching data set of 9 characters obtained from the classical GA, the number of layer is 3, the number of hidden node is 100, learning rate is 0.3, and momentum is 0.5, the artificial neural network trained enables us to attain the approximately desired holograms, which are fairly good agreement with what we suggested in the theory. The second step, effect of several parameters on the operation of the hybrid algorithm is investigated. In principle, the operation of the hybrid algorithm and GA are the same except the modification of the initial step. Hence, the verified results in Ref [2] of the parameters such as the probability of crossover and mutation, the tournament size, and the crossover block size are remained unchanged, beside of the reduced population size. The reconstructed image of 76.4% diffraction efficiency and 5.4% uniformity is achieved when the population size is 30, the iteration number is 2000, the probability of crossover is 0.75, and the probability of mutation is 0.001. A comparison between the hybrid algorithm and GA in term of diffraction efficiency and computation time is also evaluated as shown in Fig. 2. With a 66.7% reduction in computation time and a 2% increase in diffraction efficiency compared to the GA method, the hybrid algorithm demonstrates its efficient performance. In the optical experiment, the phase holograms were displayed on a programmable phase modulator (model XGA). Figures 3 are pictures of diffracted patterns of the letter "0" from the holograms generated using the hybrid algorithm. Diffraction efficiency of 75.8% and uniformity of 5.8% are measured. We see that the simulation and experiment results are fairly good agreement with each other. In this paper, Genetic Algorithm and Neural Network have been successfully combined in designing CGHs. This method gives a significant reduction in computation time compared to the GA method while still allowing holograms of high diffraction efficiency and uniformity to be achieved. This work was supported by No.mOl-2001-000-00324-0 (2002)) from the Korea Science & Engineering Foundation.

• Asia pacific journal of information systems
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• v.18 no.3
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• pp.21-43
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• 2008

The task network which is formed of different individuals can be recognized as a social network. Therefore, the way to communicate with people inside or outside the network has considerable influence on their outcome. Moreover, the position on which a member stands in a network shows the different effects of the information systems supporting communication with others. In this paper, it is to be studied how personal CMC (computer-mediated communication) tools affect the mission that those who work for a network perform through diverse task networks. Especially, we focused on synchronicity of CMC. On this score, the perspective of Media Synchronicity Theory was taken that had been suggested by criticizing Media Richness Theory. It is the objective, from this perspective, to find which characteristics of networks make the value of IT supporting synchronicity high. In the research trends of social networks, there have been two traditional perspectives to explain the effect of network: embeddedness and diversity ones. These differ from the aspect which type of social network can provide much more economic benefits. As similar studies have been reported by various researchers, these are also divided into the bonding and bridging views which are based on internal and external tie, respectively, Size, density, and centrality were measured as the characteristics of personal task networks. Size means the level of relationship between members. It is the total number of other colleagues who work with a specific member for a certain project. It means, the larger the size of task network, the more the number of coworkers who interact each other through the job. Density is the ratio of the number of relationships arranged actually to the total number of available ones. In an ego-centered network, it is defined as the ratio of the number of relationship made really to the total number of possible ones between members who are actually involved each other. The higher the level of density, the larger the number of projects on which the members collaborate. Centrality means that his/her position is on the exact center of whole network. There are several methods to measure it. In this research, betweenness centrality was adopted among them. It is measured by the position on which one member stands between others in a network. The determinant to raise its level is the shortest geodesic that represents the shortest distance between members. Centrality also indicates the level of role as a broker among others. To verify the hypotheses, we interviewed and surveyed a group of employees of a nationwide financial organization in which a groupware system is used. They were questioned about two CMC applications: MSN with a higher level of synchronicity and email with a lower one. As a result, the larger the size of his/her own task network, the smaller its density and the higher the level of his/her centrality, the higher the level of the effect using the task network with CMC tools. Above all, this positive effect is verified to be much more produced while using CMC applications with higher-level synchronicity. Among the a variety of situations under which the use of CMC gives more benefits, this research is considered as one of rare cases regarding the characteristics of task network as moderators by focusing ITs for the operation of his/her own task network. It is another contribution of this research to prove empirically that the values of information system depend on the social, or comparative, characteristic of time. Though the same amount of time is shared, the social characteristics of users change its value. In addition, it is significant to examine empirically that the ITs with higher-level synchronicity have the positive effect on productivity. Many businesses are worried about the negative effect of synchronous ITs, for their employees are likely to use them for personal social activities. However. this research can help to dismiss the concern against CMC tools.

• Journal of Sericultural and Entomological Science
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• v.13 no.1
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• pp.49-59
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• 1971

This experiment was conducted, how making use of "Seracol 100", a kind of nonionic surface active reagent, during cocoon cooking and silk reeling process which is mainly used in Korea and developed by one of the authors since 1965. Main purpose of the experiment is to investigate the influence of the activity of the reelability aid reagent on various degree of hardness component and various salts which are contained in filature water being used by silk factories now. Specifically, it was tried to determine the effects of the reelability aid reagent added to each sample water of artificially differentiated the degree of hardness component upon sericin solubility. Some of the major findings are summarized as follows. 1. "Seracol 100", with below 5$^{\circ}$dH water, increased sericin solubility in each sample water, but above $10^{\circ}$dH the effect of it shows a significant relationship with the different degree of hardness component. Besides the component (MgCO$_3$)$_4$ㆍMg(OH)$_2$, generally, the higher the degree of hardness in the water, the less the amount of desolved sericin in the water showed. There is little or no difference between 1000 times diluted "Seracol 100" water and 2000 times diluted "Seracol 100" water in terms of sericin solubility. 2. The different kind of degree of hardness component shows a significant relationship with sericin solubility, In case use of "Seracol 100", Mg hardness component affected on the sericin solubility more than Ca hardness. But in the control, contrary to this, that is Ca hardness component did more than Mg hardness, 3. The different kind of salts in degree of hardness component show a significant relationship with sericin solubility. In the control water, nitrate is the greatest among salts affecting on sericin solubility, next chloride and sulfate are in order. In case of "Seracol 100" water, chloride is the least among salts, below $10^{\circ}$dH, next sulfate and nitrate are in order, and above 15$^{\circ}$dH, next nitrate and sulfate are in order. 4. In case of "Seracol 100" water, the more contained heavy metal salts (Fe, Al, Cu, Mn) in the water, the less sericin solubility showed. It is found that there is little or no difference among other salts in terms of sericin solubility. But alkaline metal salt remarkably increased sericin solubility. 5. In case of "Seracol 100" water, tinting of the water was affected by Ca salts more than by Mg salts. Among other salts, only Al and Fe affected on the tinting of the water, specifically, in view of the fact that "Seracol 100" water increase the tinting of Fe salt water, but decrease the tinting of raw silk. It is thought that "Seracol 100" deter Fe$^{+2}$ from absorbing to raw silk by deteriorating the activity of Fe$^{+2}$ . 6. "Seracol 100" have the effect on osmosis of the water, After treatment until 2hrs the osmosis of 1000 times diluted "Seracol 100" water is the greatest, next orders are 2000 times diluted "Seracol 100" and control. From 2 hrs to 6 hrs the osmosis of 2000 times diluted water is the greatest, next orders are 1000 times diluted water and control. After 6 hrs the osmosis of the water is the same order as above. 7. In view of tile fact that "Seracol 100" have the effect to control the degree of hardness during the treatment of cocoon layer in the water, it is thought that, in varying degree of hardness in the water, there is a significant relationship between "Seracol 100" and degree of hardness components in cocoon layer.

• Journal of agricultural medicine and community health
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• v.16 no.1
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• pp.48-60
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• 1991

In a seroepidemiological study in several areas of Korea, the ELISA technique was performed to determine prevalence of some important helminthic diseases in our nation during March $15^{th}$ to June $30^{th}$. 1991. In this survey the serum antibody positive rates of anisakiasis, toxocariasis, clonorchiasis, paragonimiasis, cysticercosis, and sparganosis were measured. Among, 6,704 cases examined, 19.7% showed positive antibody titer at least one of the six items studied. Overall positive antibody rate was 8.1% in anisakiasis, 5.6% in toxocariasis, 3.6% in clonorchiasis, 1.7% in paragonimiasis, 4.5% in cysticercosis, and 2.6% in sparganosis respectively. In Pusan port southeastern part of Korea, antibody positive rate of anisakiasis was 2.9%, and clonorchiasis was 2.8% among 450 examine. In TaeJ$\check{o}$n city, central part of Korea. toxocariasis(6.7%) and anisakiasis(3.7%) showed high serologic positive rate. Of the 875 persons in Chunche$\check{o}$n gun(=province), northern central rural area of South Korea, anisakiasis was revealed as 3.4% seropositivity. In Tonghae port, eastern coast of South Korea. 9.9% of population examined showed positive antibody titer in anisakiasis. Of the 1,122 persons examined in Southern part of Cholla-Namdo(Southwestern coastal area of Korea), anisakiasis was 16.9%, cysticerocosis was 12.7% and the paragonimiasis was 3.3% respectively. In some localized area of Cholla-Pukdo, anisakiasis was 9.3% and cysticekosis was 4.3% among 702 cases examined. In some localized area of Kyungsang-Pukdo, anisakiasis was 10.6%. and toxocariasis was 16.1% among 900 cases examined. And finally, in Cheju-do, southern island of Korea, anisakiasis showed high positive rate(6.7%). Because cross reactions between related helminth group may disturb the analysis of these data, use of further developed techniques such as EITB(enzyme-linked immunoelectrotransfer blot) was considered as a essential tools for the study. We thought that probably most of the positive cases of cysticerosis were taeniasis cases. We can't rule out taeniasis even though EITB was employed as far as crude worm extract or cystic fluid of cysticercus was used as antigen. It was well Known that toxocariasis and anisakiasis also showed cross reactivity. However, the data presented here focus on seropositive rate of several helminthic diseases in Korea, not true prevalence rate of helminthiases, and to wait for more expensive purified antigen in sufficient amount for epidemiologic use is not necessary because increased immunologic sensitivity had little effect on epidemiologic sensitivity. We, here, suggest that ELISA should be applied as soon as possible to the evaluation of prevalence of tissue invading parasitic diseases, and a review of the antibody positive rate obtained in this study would be a basic data for controlling program of parasitic diseases in Korea.

• Journal of Science Education
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• v.34 no.2
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• pp.291-305
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• 2010

The aim of this study was to survey the perceptions of the elementary school teachers on the smallscale chemistry(SSC) following its training session. The teachers participating in the survey were 266 teachers in the Gyeongnam province. They were given a questionnaire that focused on the nine areas of the SSC: Needs for the teacher training and its application, its benefits, issues of safety and danger as well as treatment of environmental pollution, its economic efficiency and the development of investigative skills. The designed questionnaire was checked by an authority, and the responses to each question were tallied and analyzed. The results are as follows. The biggest problems of the traditional experimental methods as rated by the teachers were, in the order of importance, the preparation time, the legal liability of teachers for the safety and accidents, financial issues, disposal of the experimental wastes and the lack of relevant data. Since most of the teachers had not experienced the SSC lab programs in the field, they responded positively to the questions of need for its introduction and training. The implementation of the experimental SSC lab programs should proceed in the following order: introduction into the textbook, teacher training program, after-school education and the invitation of instructors. The most useful materials for the SSC program were CDs, videos, books and various printed materials, in that order. The responses regarding benefits of the SSC program included its simplicity, convenience, time savings, diversity, qualitative and quantitative aspects, integration into the regular class and use of toys. In particular, the teachers mentioned the increased safety due to the small amount of experimental reagents needed and the durability of plastic instruments. The familarity from the use of everyday tools as well as easy access to and the low-cost of the instruments were other important benefits. The teachers in general rated the educational content of the program highly, but many also found it to be average. Some pointed out the lack of sufficient discussion due to the individual or pair groupings as a potential shortcoming. The potential for development of problem solving ability and improvement of skills was rated positively. The number of teacher who rated the development of creativity positively was just over the half. As for the area of improving investigative skills, many found its assessment difficult and confusing because of the lack of its systemic definition and categorization. Based on the findings of this study, I would like to recommend the application and a wider dissemination of the small-scale chemistry lab program into the elementary school science curriculum.

• Hwankyungkyoyuk
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• v.7 no.1
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• pp.46-87
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• 1994

Our country has been consuming a huge amount of energy in the course of industrialization and its demand is expected to increase enormously in the future. However, the deposits of energy resources are so limited that the settlement of energy problem comes up the essential subject. To solve the energy problem, it is requested that new resources to gain energy stably should be developed and also energy should be economized and used effectively. The effective use of energy and an the wisdom of economy in energy are requested to everybody and these things should be habitualized from very young age through education. Nevertheless, almost every school in our country hasn’t been concerned about energy education. Even though they have a concern, they are very short of the energy education materials and the quality of the materials is not so good. Therefore it is very meaningful to the settlement of energy problem of the country to make the students who will lead our country to make the students who will lead our country in the future realize the seriousness of energy problem and to provide them the necessary knowledge and methods to solve this problem so that they practice those things in everyday life. Having these necessities, this research, supported by The Korea Energy Management Corporation(KEMCO), was performed for 8 months from April 17, 1994 to December 17, 1994. Many peoples participated in this study such as 30 staffs of researchers and authors, 5 staffs of photographers and illustrators, and 3 VCR program producers developing an energy education material set for middle school students that includes a printed material for student, a diskette for computer simulation, a teacher's guidebook, VCR material and its guidebook. The following main development direction was established : First, the material for student should be consisted of units that let students know the seriousness of energy problem. Second, the focus should be put on the necessary method and practice to economize energy actually in real life based on the basic knowledge learned in elementary school. Third, material for student should be consisted of modules to be student activity-oriented teaching-learning rather than lecture-oriented one. The activity, to maximize student's interests, should be presented in various forms such as experiments, investigation, play, data interpretation, computer simulation, visits, expression and appreciation, etc. To develop the energy education materials for middle school students, a research plan was made first. After literature review about domestic and foreign energy education materials, several research trips home and abroad, and discussion meetings, the basic theory of energy education such as the principle, objective, contents, teaching-learning method, and evaluation method was established. Material for student was developed through the following procedures : The activities in the existing energy education materials were analysed and were divided into four categories related to energy using places of home, school, community, and country, and which were again divided into three categories related to time of past, present, and future, Considering these division, nine modules which are structure units of material for student were chosen, Each module comprises 2-4 activities. Totally 31 activities were designed in this way. The syllabi were made out for each activity and writing was asked for to experts related to each activity after several discussions and revision. To complement the draft, another several discussions and revision were also made on it and then pictures and illustrations were asked for. All these procedures complete the material for student, titled ; Energy Inquiry of Middle School Students', which totals 129 pages and is all in color. As the manuscript of material for student was fixed, writing for teacher's guidebook was asked for to the same writers. The draft of teacher's guidebook was also complemented through the several concentrated works and discussions. Teacher's guidebook focused on the teaching-learning principle and methods of energy education and on the concrete instruction cases for effective instruction of material for student. It is organized with two parts : the one is 'general outline' which introduces theoretical contents and the other is 'details' which are practically helpful to teaching-learning. It is totally 131 pages including both 'general outline' and 'details'. The VCR material and its guidebook consist of contents that cultivate the good attitude trying to economize energy and raise student's interests with a purpose of strong motivation to recognize the necessity of economy and practice it. After establishing development direction of VCR material through discussion meetings and research trips, its script was made by relevant experts. Then the script was also reviewed two times. The drafted VCR material made by a video material developing expert was examined and modified by previews twice. After completion of VCR material, the VCR guidebook was made. All these procedures led to the development of VCR material which runs 20 minutes in VHS type. The VCR guidebook shows a production purpose of the program, structure of contents, evaluation methods, and contents of the program in detail to give help to instructors when they use this VCR material, When these energy education materials are used, it is desirable that the VCR material should be presented first to induce student's motive, and then material for student is introduced Since the material for student is composed of activity-oriented modules and each module is independent one another in general, and each activity is, too. the necessary module or activity can be chosen and utilized in any order according to school or class conditions. This energy education materials will contribute to the development of student's ability to solve energy problem in everyday life and teacher's ability to teach the fundamental knowledge and method in solving energy problem.

• Journal of Korean society of Dental Hygiene
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• v.4 no.1
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• pp.49-64
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• 2004

This study is designed to conduct a questionnaire research into the safety control and the actual condition of radiography by working with dentistry belonging to university hospitals, dental hospitals and dental clinics for three months ranging from August, 2003 to October, 2003. The researcher came to the following conclusions. 1. The research on the current condition of possessed radiational equipment shows that 61.2 percent of the subjects had one intraoral radiation medicine and that 70.1 percent of the subjects had more than one extraoral radiation medicine and that 37.3 percent of the subjects had more than one digital radiation medicine. 2. Most of intraoral radiography (82.1%) was conducted by dental hygienists, and 7.5 percent of intraoral radiography was conducted by nurse aids. On the other hand, most of extraoral radiography (76.6%) was conducted by dental hygienists and digital radiography was conducted by dental hygienists(60.6%), dentists(32.0%) and radiographer(80.0%). 3. The less-than 1-meter-long distance between cone and the radiographer accounted for 44.8 percent. And the more-than 1.6-meter-long distance accounted for no more than 13.4 percent. The exposure time per standard film which was adjusted to each part accounted for 71.6 percent. Fixing the film on the part of healthy patients accounted for 76.1 percent. Fixing the film of elderly patients and children patients by the radiographer accounted for 43.3 percent. 4. The average daily photographing frequency of standard films stood at six to ten pieces(31.3%), and the average weekly photographing frequency of bitewing films stood at less than one piece(47.8%), and the dentistries where bitewing films were not employed accounted for 25.4%. The subjects whose average weekly photographing freqeuncy of occlusal films stood at less than a piece accounted for 59.7 percent. The dentistries whose average weekly photographing frequency of pediatric films stood at one to five pieces accounted for 41.8 percent. In case of panorama & cephalo, one to five pieces on a weekly average accounted for 36.2 percent. The dentistries whose average daily photographing frequency of digital radiation medicine stood at less than 1 piece accounted for 40.0 percent. 5. The research on the use of protective clothes shows that pregnant ·women only accounted for 31.3 percent. In regard to the use of protective clothes in case of the radiographers fixing films, the cases where no protective clothes were employed accounted for 88.1 percent. The reason was said to he attributable to the trouble related to wearing the clothes(54.2%). 6. The survey on the measurement of exposure dose shows that the cases where no measurement was made accounted for 76.1 percent. As far as the measurement methods of exposure dose was concerned, the employment of film badge accounted for 68.8 percent. The subjects turned out to conduct measurement of exposure dose every third month, which accounted for 43.8 percent. The barriers to the measurement of measurement of exposure dose were attributable to the recognition that a little amount of exposure dose need not be measured(29.9%). 7. The survey on the distinction of radiation rooms and clinic rooms reveals that the cases where radiation rooms exclusively existed accounted for 67.2 percent. 43.3 percent of the subjects turned out to have only one protective garment, and 49.3 percent of the subjects proved to conduct a periodical checkup of radiational equipment. The survey on the examination certificates of radiational generators and protective facilities indicates that 80.6 percent of the subjects had the certificates. The research also shows that the subjects with the marks indicating the radiational areas accounted for 70.1 percent. And trustees turned out to handle developing solutions and fixing solutions.