• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.105-113
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• 1995

Seasonality in biomass and egg Production was investigated for Calanus sinicus, one of the major copepods in Asan Bay, Korea. Biomass of this species in this restricted embayment showed only one Peak in spring, but e99 Production showed two Peaks, spring (April and May) and fall (September). Average egg Productions during the spawnlng seasons were 16.3 egg/female/day (spring) and 7.6eggs/female/day (fall) with maximum egg Production of 39.0 eggs/female/day. Food concentrations in this bay measured'1 terms of particulate organic carbon (POC) were relatively high around the year, and correlation between egg Production and POC was not significant. With the food Provided sufficiently animals Produced a lot of fecal Pellets, but egg Production was ceased after several days of experiment. From these results it was believed that egg Production in this bay was influenced by food quality and feeding history rather than food concentrations. Habitat temperatures also seem to have influence on egg Production from the tacts that no egg was Produced at extreme habitat temperatures, although the correlation between the two was not significant. In this bay, two generations with different time periods seem to progress yearly. Distribution was coupled with life cycle only at certain time of the year. During the other periods predation pressure by the higher trophic levels and shift of the centers of the distributions toward deeper outer bay seemed to be responsible for the observed distribution and egg Production of this species in this bay. Comparing with the Previous reports, migration of fairly long distance and continual reproduction seemed possible for this species.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.425-433
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• 2016

The construction of a light rail transit (LRT) system is a large and complex infrastructure project involving hundreds of billions of won in construction costs for a single route, and it is very important to carry out such a project from a life-cycle perspective because of its long-term operation. Systems engineering is a means and methodology to successfully implement customers' needs, and it is useful in large projects such as light rail transit. An application model called Systems Engineering for Light Rail Transit (SELRT) was developed to support systems engineering activities in light rail transit projects. In order to utilize SELRT, it is necessary to ensure that system requirements are met. As such, in this paper, we present a verification procedure and architecture based on a systems engineering-based methodology, thereby identifying the system requirements and deriving the verification requirements to confirm the SELRT model for the proposed method. The results show that the traceability of the system requirements and verification requirements, the verification method for each requirement, and the demonstration results for computerized tools are mutually connected, and that the initial requirements are clearly implemented in the SELRT. The proposed method is valid for verifying the SELRT, which can also be utilized in a LRT project.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.139-148
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• 2011

Asphalt concrete overlay method is used by general maintenance and rehabilitation of construction for aged concrete pavement in Korea. However, in case of the AC overlay method to extend service life of the existing concrete pavements, various distresses of reflection crack, pothole and rutting are the typical problems of the asphalt overlay on existing concrete pavement since it has different physical characteristics between asphalt overlay and existing concrete pavement. To achieve this, application of concrete overlay method is required instead of AC overlay method. Concrete overlay method has advantages that can reduce maintenance cycle and costs since it has excellent bearing value for heavy vehicles and no rutting. However, technical problems of detour road construction, traffic control and other disadvantages happened by long curing time. Thus, in this study and experimental research were launched to evaluate the workability, durability and resistance against environmental loading of Very Rapid Hardening Acrylic Polymer Modified Concrete(VRH-APMC) for application of bonded concrete overlay method. Test results showed that the compressive and bond strength were exceed 21MPa and 1.4MPa of target strength after four hours for rapid traffic opening properties. And tests of resistance against environmental loading results showed that VRH-APMC secured excellent durability. Thus, it was known that VRH-APMC was suitable material for large scale bonded concrete overlay method, and it was possible to use maintenance and rehabilitation method which needs enough workability and rapid traffic opening.

• Journal of Korean Academy of Nursing
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• v.30 no.1
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• pp.39-46
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• 2000

This study, was done to compare the nursing education systems of China and South Korea (Korea), then, on the basis of this comparison, to examine the direction of nursing education in China. The results the study are as follows : 1. Nursing education in Korea was influenced by social change, political policy, but as it was established, nurses in Korea, were able actively involved in presenting nursing education development proposals to the government, and in developing nursing education through their own efforts. Nursing education in China developed through the political policy of a socialist Country. During the period of modernization after 1977, a nursing education developed very quickly, In 1983, the first baccalaureate nursing education program was established and, in 1992, the first masters program was opened. 2. In Korea, there are two nursing education systems; diploma and baccalaureate, and there is only one entry level, high school graduation. In China today, on the other hand, there are three types of nursing education systems; technical, diploma, and baccalaureate, and they have middle school and high school graduation as the two levels of entry. 3. There are similarities between China and Korea in curriculums for nursing education which include the major nursing concepts. But in descriptions of the education objectives, China the emphasis is on training the 'expert' in clinical nursing which is not consistent with their educational philosophy. Korea differs from China in that the focus is on training for 'multiple ability' to be used in both clinical and community environments. 4. In Korea, the curriculum is organized with the theoretical and clinical experience combined. The curriculum is oriented to the life cycle and human developmental process. In China, however, the curriculum is organized so that after finishing the theoretical part of the curriculum, the students begin a one year intensive field experience in which the major clinical field is the hospital, and the focus is on disease oriented care and research ability. 5. In order for nurses to be proposed to address nursing education system needs follows : to change as The new nursing education system should be baccalaureate education in order to improve the education level in all nursing education programs, to develop doctoral programs, to open nurse specialist programs, and to develop a new curriculum based nursing philosophy and health delivery system change. New nursing curriculum for health care in China in the 21st century should be directed by a framework based on nursing philosophy, objectives and nursing content. In conclusion, the study will contribute China nursing education system revolution for policy develop and curriculum research. According to these results, in the future, nurses in China should be more actively involved in research and in a nursing education revolution, Also they should be involved in building information networks and in developing long term projects in nursing education.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.25 no.2
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• pp.26-41
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• 2020

In order to culture a life for the physiological and ecological research of the meiofauna, this study aimed to identify the most ideal condition in which the meiofauna can be cultured within a laboratory by setting various environmental conditions. The sediment deposits and seawater were collected from the intertidal zone in Mallipo of the west coast. A aquarium in which the internal environment can be controlled by constantly maintaining the temperature and humidity was fabricated and the culture experiments of the collected meiofauna were conducted together with the sea water and sediment deposits collected. The experiment 1 was conducted after establishing the similar environment as the collecting location. Under the same condition as the experiment 1, the experiment 2 verified a difference between when live foods were supplied and were not. In the experiment 3, the changes in the meiofauna colony were checked according to with or without light and live foods. In the results of culturing experiments, the habitat density and the number of appeared classification groups of the meiofauna colony were relatively higher both in the water tank with supplying the live foods and under the condition of having light in 12-hour cycle than those in the aquarium without live foods and under no light condition. In addition, the habitat density of meiofauna cultured within a laboratory exhibited relatively higher value than that under the natural state.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.174-183
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• 2001

During the rapid phase of gonadal development of the freshwater teleost, the catfish (Silurus asotus), the influence of hCG upon the inducement of final oocyte maturation and spawning was investigated electrophoretically and ultrastructurally. The electrophoretic patterns obtained were different in the presence and absence of some of the major or minor zones, because of the hormone level in catfish. The vitellogenin of hormone-treated fish was stained more intensively than that of sham-treated fish. These proteins showed some minor or main bands of egg extracts which migrated at positions corresponding to molecular weights of approximately 90,000. However, the thickness of electrophoretic band in molecular weight for hCG-treated fish was slightly lower than that for saline control. It seemed the plasma protein with molecular weight of approximately 45,000 in hCG-treated fish disappeared. In contrast to the control fish, the ovaries in the catfish treated with hCG shows a marked ultrastructural change under the electron microscope. No dilated profiles were seen in the granulosa cells of the mature oocyte before ovulation. After germinal vesicle breakdown (GVBD), the zona radiata interna (ZRI) becomes more compact, and there is a loss of all the processes from the pore canals. There is a wide space between the vitelline membrane and zona radiata. Also, during final maturation, the microvillar processes from the oocyte are seen no longer to penetrate deeply into the extracellular spaces of the overlying granulosa cells, and the reticulate patterns of the zona radiata interna becomes occluded, giving the zona radiata a more solid appearance. It has been possible to initiate 100% oocyte maturation in yolk granules and follicles in vivo by treatment with hCG and a high water temperature ($27^{\circ}C$). In hCG-treated fish, the percentages of successful artificial fertilization and hatching were maximal at 15 h after a single injection. It seems clear that a long acting preparation containing hCG can be successfully used in prespawning fish to advance the final events of gonadal maturation and initiate spawning. Further studies are necessary to evaluate the potential of hCG to either stimulate or inhibit the reproductive development of fish at other stages of the seasonal reproductive cycle.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.1
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• pp.58-66
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• 2014

Water pollution problems of urban rivers due to the urbanization and industrialization have been the subject of public attention. In particular, considering the fact that the characteristics of water cycle of each basin change dramatically through the development of new towns, a large number of concerns about future water quality have been raised. However, reasonable measures to predict future water quality quantitatively have not been presented by this moment. In this study, by the linkage of annual unit load generation based on long-term monitoring results of the ministry of environment (MOE) to a semi-distributed rainfall runoff model, SWMM (Storm Water Management Model), we proposed a new methodology to estimate future water quality macroscopically and testified it to verify its applicability for the estimation of future water quality of a small watershed at G new town. As a result of the estimation using Y-EMC (Yearly based Event Mean Concentration), future water quality were simulated as BOD 18.7, T-N 16.1 and T-P 0.85 mg/L respectively which could not achieve the grade III of domestic river life guidance and these criteria could be satisfied by the reduction of domestic wastewater discharge load by over 80%. The results of this study are shown to be utilized for one of basic tools to estimate and manage water quality of urban rivers in the course of new town developments.

• Applied Microscopy
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• v.33 no.1
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• pp.25-39
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• 2003

Cell differentiation and ultrastructural characteristics in the seminiferous epithelium of Myotis macrodactylus was investigated with the light and electron microscopes. Spermatogenesis has begun at April and finished at September. The nuclei of A spermatogonia (dark and pale type of spermatogonia) were oval, applied to the basal lamina, and surrounded by Sertoli cells. By comparison with other types of spermatogonia, the cell and nucleus of B type of spermatogonium is globular and larger than A types of spermatogonia. The nucleolus appears as a coarse and touches the nuclear membrane. The cell and nucleus of spermatocytes was globular and larger, but primary spematocyte is larger than secondary spermatocyte. Spermiogenesis was divided according to the level of fine structural difference, into Golgi, cap, acrosomal, maturation and spermiation phases; Golgi, cap, acrosomal and spermiation phases were further subdivided into steps of early and late phase respectively, and maturation phase has only one step. Hence, the spermiogenesis has been divided into a total of nine phases. In the change of karyoplasm, the chromatin granules are condensed at late Golgi phase and completed at spermiation phase. The sperm tail began to develop in early Golgi phase and completed in spermiation phase. The process of degeneration of spermatogenic cells in the seminiferous tubules was continually observed from October, before the beginning of hibernation, to hibernation phase (November, December, January, February, March). Immatured spermatogenic cells in the seminiferous tubules have been engulfed by phagocytosis of Sertoli cells during period of degeneration. It is deduced that the adaptative strategy serves as the mechanism to regulate the effective use of energy to prepare for long hibernation and regulation of breeding cycle.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.5
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• pp.402-415
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• 2001

Advantages of flash memories are their shock resistance and fast read speed, which is much faster than that of a HDD. Because of these characteristics, they are increasingly used in the traditional household electric appliance and portable handset and therefore, development of file systems which use them as storage medium is increasingly needed. But they have two problems as storage medium. First, data stored in them cannot be overwritten: it must be erased before new data can be stored. Unfortunately, this erase operation usually takes about one second. Consequently, updating data in flash memories takes long time. In this paper, their problem is solved by using a data update mechanism like LFS(Log-structured File System). Second, their erase operations are restricted. We propose novel cleaning policy in order to increase the life cycle. We implemented FAT file system, which is suitable to small storage medium and solved problems, which usually happen in implementing FAT. We evaluated the performance of sequential writes and random writes on our implemented flash file system.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.645-654
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• 2019

The purpose of this study was to analyze the current status of and necessity for forest education in Korea in order to promote educational programs on the topic among different age groups. A survey conducted among 1,542 adults nationwide indicated that different age groups had variable degrees of awareness and experience of forest education programs. Specifically, older people responded more positively in terms of awareness, experience, and willingness to engage with forest education programs, and engaging in individual holistic development. In addition, participant companion types and motivation for participating in forest education programs were different among age groups. Regarding motivation for participating in forest education programs, all groups answered, "to enjoy the forest landscape," "to experience new things," and "to refresh themselves." In particular, individuals in their 30s had a desire to learn, while those in their 50s had a desire for a healthy lifestyle. Additionally, people in their 40s showed the highest participation rate in forest education programs, alongside their children and family members. In terms of operating period, older individuals preferred long-term operating programs. Accessibility was the most important factor for all age groups when selecting forest education programs. We hope that this study will be useful for the development and promotion of forest education programs for all age groups.