• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.158-164
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• 1985

The objective of the study was to investigate growth pattern of capsule and grain to improve grain filling during the grain filling period in sesame. Growth patterns of capsule and grain from anthesis to maturity were measured and compared by different plant types. Growth of capsule length started to grow just after anthesis and recorded maximum point at 35 days after flowering. and then decreased gradually. Growth of higher part capsule was worse than lower and middle capsules. Capsule growth of 2 carpels 4 loculi type showed better than 4 carpels 8 loculi type and BTB (branch, 3 capsules, 2 carpels, 4 loculi) type showed good growth due to its small reduction of higher part capsule length compared to those of lower and middle parts. The order of growth of capsule length were considered to be center capsule in main stem> center capsule in branch> side capsule in main stem> side capsule in branch. Growth of capsule width also showed maximum at 35 days after anthesis and then reduced. The order of growth of capsule width were lower part> middle part> higher part. Higher part capsule width of 3 capsules 4 carpels 8 loculi type showed serious decrease at late reproductive growth stage same as those of capsule length. Fresh one thousand grain weight showed peak at 35 days after anthesis and then reduced. The order of grain growth were appeared as lower part> middle part> higher part. Growth of fresh one thousand grain weight of branch and side capsule were lower than those of main stem center capsule, and 4 carpels 8 loculi type was deeply decreased at late flowering time in higher part such as the growth of capsule length and width. BTB (branch, 3,2/4) type didn't show much decrease in higher part fresh grain weight compared to those of other plant types in spite of its profitable character of lots of sink capacity. BTB type appeared to be ideal for improving grain filling and yield productivity in growing sesame in Korea.

• Journal of Environmental Policy
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• v.5 no.1
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• pp.45-70
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• 2006

China has achieved great economic growth above 9% annual since it changed to more of a market economy system by its reform and open-door policy. At the same time, China has experienced severe ecological deterioration, such as air and water pollutions caused by its rapid urbanization and industrialization. China is now confronted with environmental pollution and ecological deterioration at a critical point, at which economic development in China is limited. Moreover, environmental problems in China have become a lit fuse for social fluctuation beyond pollution problems. The root and background of environmental problems in China, firstly, are its government's lack of understanding of these problems and incorrect economic policies affected by political and ideological prejudice. Secondly, the plundering of resources, 'the principle of development first' which didn't consider environmental sustainability is another source of environmental deterioration in China. In addition, a huge population and poverty in China have increased the difficulty in solving its environmental problems, and in fact have accelerated them. The Chinese government has established many environmental laws and institutions, increased environmental investments, and is enlarging the participation of NGOs and the general public in some limited scale to solve its environmental problems. However, it has not obtained effective results because of the lack of environmental investments owing to the government's limit of the development phase, a structural limit of law enforcement and local protectionism, and the limit of political independency in NGOs and the lack of public participation in China. It seems that China remains in the stage of 'economic development first, environmental protection second', contrary to its catch-phrase of 'the harmony between economic development and environmental protection'. China is now confronted with dual pressure both domestically and abroad because of deepening environmental problems. There are growing public's protests and demonstrations in China in response to the spread of damage owing to environmental pollution and ecological deterioration. On the other hand, international society, in particular neighboring countries, regard China as a principal cause of ecological disaster. In the face of this dual pressure, China is presently contemplating a 'recycling economy' that helps sustainable development through the structural reform of industries using too much energy and through more severe law enforcement than now. Therefore, it is desirable to promote regional cooperation more progressively and practically in the direction of building China's ability to solve environmental problems.

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.2
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• pp.21-26
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• 2016

Purpose Because of many advantages, PET-CT Scanners generally use CT Data for attenuation correction. By using CT based attenuation correction, we can get anatomical information, reduce scan time and make more accurate correction of attenuation. However in case metal artifact occurred during CT scan, CT-based attenuation correction can induce artifacts and quantitative errors that can affect the PET images. Therefore this study infers true SUV of metal artifact region from attenuation corrected image count -to- non attenuation corrected image count ratio. Materials and Methods Micro phantom inserted $^{18}F-FDG$ 4mCi was used for phantom test and Biograph mCT S(40) is used for medical test equipment. We generated metal artifact in micro phantom by using metal. Then we acquired both metal artifact region of correction factor and non metal artifact region of correction factor by using attenuation correction image count -to- non attenuation correction image count ratio. In case of clinical image, we reconstructed both attenuation corrected images and non attenuation corrected images of 10 normal patient($66{\pm}15age$) who examined PET-CT scan in SNUH. After that, we standardize several organs of correction factor by using attenuation corrected image count -to- non attenuation corrected count ratio. Then we figured out metal artifact region of correction factor by using metal artifact region of attenuation corrected image count -to- non attenuation corrected count ratio And we compared standard organs correction factor with metal artifact region correction factor. Results according to phantom test results, metal artifact induce overestimation of correction factor so metal artifact region of correction factors are 12% bigger than the non metal artifact region of correction factors. in case of clinical test, correction factor of organs with high CT number(>1000) is $8{\pm}0.5%$, correction factor of organs with CT number similar to soft tissue is $6{\pm}2%$ and correction factor of organs with low CT number(-100>) is $3{\pm}1%$. Also metal artifact correction factors are 20% bigger than soft tissue correction factors which didn't happened metal artifact. Conclusion metal artifact lead to overestimation of attenuation coefficient. because of that, SUV of metal artifact region is overestimated. Thus for more accurate quantitative evaluation, using attenuation correction image count -to-non attenuation correction image count ratio is one of the methods to reduce metal artifact affect.

• Korean Journal of Weed Science
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• v.7 no.3
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• pp.265-279
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• 1987

About 140 weed species belonging to 42 families occurring in summer were observed in Ulreung island. The Compositae was the most wildely occurring family covering 27 weed species, followed by 21 species in Graminae, 9 in Polygonaceae, 7 in Leguminosae, and 7 in Labiatae etc. In terms of the lands classified, about 60 species in 26 families were observed in the cultivated and the medical crops grown areas, respectively, and 116 species in 40 families occurred in the non-cultivated land like the vicinity of the cultivated area and 94 species in 34 families in the valley. No. of species and families were much greater in the non-cutivated land than those of the cultivated one. The most dominant weed species in both the cultivated and its vicinity in Ulreung island were Digitaria sanguinalis, followed by Portulaca oleracea, Polygonum hydropiper, Equisetum arvensis, Artemisia princeps, Commetina communis, Setaria viridis in order. Community analysis was done by the method of Toyohara in two cultivated lands such as the general crop land and the medical herb crop grown land, and two non-cultivated areas such as the vicinity of the cultivated land and valley. The cultivated land consisted of the communites of P. hydropiper and Cyperus amuricus, including Bidens tripartita in P. hydropiper community. The medical crop grown land composed of three major communities like P. hydropiper, Amaranthus mangostanus and Sonchus asper in which A. mangostanus and S. media were presented in the ecoton, indicating community being transiting. In the non-cultivated areas like the vicinity of crop land, the communities of Erigeron annuus, P. oleracea, and Oxalis corniculata were dominant, and Dystaenia takeshimana was included in the community of E. annuus and Stellan'a aquatica in P. oleracea community. In the valley, Ranunculus quelpaertensis community was existed in between the communities of Sonchus asper and Plantago asiatica.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.77-93
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• 2000

Field survey on the spatio-temporal distribution of water quality and chlorophyll a concentration, and the environmental factors on the variation of phytoplankton biomass were carried out at the 23 stations for four seasons in the Shiahae, southwestern coast of Korean Peninsula from February to October in 1995. I made an analysis on biological factor as chlorophyll a concentration as well as environmental factors such as water temperature, salinity and nutrients; ammonia, nitrite, nitrate, dissolved inorganic nitrogen, phosphate, N/P ratio, silicate and Si/P ratio. The waters in the Shiahae were not stratified due to the tidal mixing and high velocity of tidal current. And the high productivity in photic layer were supported by high nutrients concentration from freshwater on lands and bottom waters The low depth of transparency in the Shiahae had a bad influence upon primary production and marine biology. In Shiahae had a sufficient nutrients for primary production during a year. Especially dissolved inorganic nitrogen and silicate were high, the other side, phosphate was low. The source of nutrients in summer and silicate supply depend on input of freshwater from lands, the other side, dissolved inorganic nitrogen and phosphate were depend on rather supplied from bottom layer by the mixing and input of seawater from outside than input of freshwater from lands. Phosphate seemed to become a limiting nutrient for the primary production at all area of Shiahae in winter and at the northern parts in other seasons. However, dissolved inorganic nitrogen seemed to do it at the southern parts in other seasons except winter. Silicate didn't become a limiting nutrient for diatoms in Shiahae. Phytoplankton biomass as measured by chlorophyll a concentration was very high all the year round, it was controlled by the combination of the several environmental factors, especially of nitrogen, phosphorus and the physical factors such as light intensity. [Spatio-temporal distribution, Seasonal fluctuation, Nnutrients, Chlorophyll a, Environmental factors, Nutrient source, Limiting Nutrient, Light, Shiahae] .

• Journal of Biosystems Engineering
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• v.4 no.2
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• pp.10-24
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• 1979

It is understood that drum speed of threshers and the moisture content of paddy grains to be threshed, respectively, have a signific:mt effect upon rice recoveries. Threshing under an increased drum speed would give a high performance rate, which is the general practice in custom work threshing in association with the use of semiauto-t hreshers. In the connection, however, it may result in the promotion of grain cracks and brokens of the rice product after milling. No reference or determination for an opti mum drum speed of the thresher is made available for various grain moisture contents at the time of the threshing operation and for different rice varieties especially for the Tongil rice varieties. This study was Conducted to find out and determine effects of the drum speeds on grain losses. The grain loss was quantified in terms of recovery rates of rice grains after treatments. Samples of each of all treatments were taken from the grain sampling plate placed in the grain conveyor of threshers. The grain sample plate was specially provided for this experiment. The brown-rice, milling, and head-rice recJveries were tes ted in the laboratory mill, respectively. Two rice varieties, Akibare and Suweon 251, each with five levels of different moist\ulcornerure contents at harvest and six levels of different drum speeds of threshers, were selected and used for treatments in this experiment. Two conditions of materials were tested in the thresher. One condition was to thresh the experimental material immediately after cutting, referred to as the wet-material thr eshing in this study. The other was to thresh the experimental :material, dried to contain about 15-16 percent of the grain moisture under the shocking operation. This is referred to as the dry-material threshing in this study. In additioon, field measurements for the grain moistures and drum-sdeeds under actual operation practices of the traditional field threshing, were conducted with a view to comparing with results of the experimental treatments. The results of the study may be summarized as follows: 1. For threshing treatments of Japonica-type rice variety (Akibare) , the effect of drum speeds and levels of grain moisture at cutting upon brown-rice, milling, and head-rice recoveries were found statistically significant. No significant difference in these recovery rates was noticed regardless of whether the material was threshed right after cutting or after drying by the shocking operation. 2. For the Tongil-sister rice variety(Suweon 251), milling recovery for the varied drum-speed and the grain~moisture level at cutting was found statististically significant. Th milling recovery was much significant when associated with the wet-material thres\ulcornerhing compared to the dry-material threshing. 3. The optimum peripheral velocity to be maintained at the edge of teeth on the thr\ulcorneresher drum was determined and may be recommanded as that of about 12 to 13 meters per second in view of the maximum recovery rate of the milled rice. 4. The effect of the drum speed on the qualitative loss of the milled rice was much greater in the case of the Tongil variety than Japonica. This effect was also greater by the wet-material threshing than by the dry-material threshing. Therefore, to apply the wet-material threshing operation for the Tongil variety, in particular, it should be very important to introduce the kind of threshing technology which would maintain the drum speed at optimum. 5. A field survey for the actual drum speed of threshing operations for 50 threshers indicated that average peripheral velccity was 12.76m/sec., and that the range was from 10.50 to 14.90m/sec. Approximately, more than 30% of the experimented and measured threshers were being operated at speeds which exceeded the optimum speed determined and assessed in this study. Accordingly, it should be highly desirable and important to take counter-measures against these threshing practices of operational overspeed.

• Journal of Biosystems Engineering
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• v.4 no.2
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• pp.9-9
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• 1979

It is understood that drum speed of threshers and the moisture content of paddy grains to be threshed, respectively, have a signific:mt effect upon rice recoveries. Threshing under an increased drum speed would give a high performance rate, which is the general practice in custom work threshing in association with the use of semiauto-t hreshers. In the connection, however, it may result in the promotion of grain cracks and brokens of the rice product after milling. No reference or determination for an opti mum drum speed of the thresher is made available for various grain moisture contents at the time of the threshing operation and for different rice varieties especially for the Tongil rice varieties. This study was Conducted to find out and determine effects of the drum speeds on grain losses. The grain loss was quantified in terms of recovery rates of rice grains after treatments. Samples of each of all treatments were taken from the grain sampling plate placed in the grain conveyor of threshers. The grain sample plate was specially provided for this experiment. The brown-rice, milling, and head-rice recJveries were tes ted in the laboratory mill, respectively. Two rice varieties, Akibare and Suweon 251, each with five levels of different moist?ure contents at harvest and six levels of different drum speeds of threshers, were selected and used for treatments in this experiment. Two conditions of materials were tested in the thresher. One condition was to thresh the experimental material immediately after cutting, referred to as the wet-material thr eshing in this study. The other was to thresh the experimental :material, dried to contain about 15-16 percent of the grain moisture under the shocking operation. This is referred to as the dry-material threshing in this study. In additioon, field measurements for the grain moistures and drum-sdeeds under actual operation practices of the traditional field threshing, were conducted with a view to comparing with results of the experimental treatments. The results of the study may be summarized as follows: 1. For threshing treatments of Japonica-type rice variety (Akibare) , the effect of drum speeds and levels of grain moisture at cutting upon brown-rice, milling, and head-rice recoveries were found statistically significant. No significant difference in these recovery rates was noticed regardless of whether the material was threshed right after cutting or after drying by the shocking operation. 2. For the Tongil-sister rice variety(Suweon 251), milling recovery for the varied drum-speed and the grain~moisture level at cutting was found statististically significant. Th milling recovery was much significant when associated with the wet-material thres?hing compared to the dry-material threshing. 3. The optimum peripheral velocity to be maintained at the edge of teeth on the thr?esher drum was determined and may be recommanded as that of about 12 to 13 meters per second in view of the maximum recovery rate of the milled rice. 4. The effect of the drum speed on the qualitative loss of the milled rice was much greater in the case of the Tongil variety than Japonica. This effect was also greater by the wet-material threshing than by the dry-material threshing. Therefore, to apply the wet-material threshing operation for the Tongil variety, in particular, it should be very important to introduce the kind of threshing technology which would maintain the drum speed at optimum. 5. A field survey for the actual drum speed of threshing operations for 50 threshers indicated that average peripheral velccity was 12.76m/sec., and that the range was from 10.50 to 14.90m/sec. Approximately, more than 30% of the experimented and measured threshers were being operated at speeds which exceeded the optimum speed determined and assessed in this study. Accordingly, it should be highly desirable and important to take counter-measures against these threshing practices of operational overspeed.

• 대한공업교육학회지
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• v.37 no.1
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• pp.183-204
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• 2012

This study was to analysis perception about Teaching & Learning Support System of the school of Rural Areas in Korea. In order to accomplish the study purpose, the study conducted a research through Web Survey method and examined their recognition. Major findings of this study were as follows: First, Student was satisfied with TLSS of the school of Rural Areas in Korea. Students would like to 'using e-learning with Electronic board and Tablet PC' among program contents. But the system' utilization was low. However, 90% of the students wanted that teacher usually using the FASTEL. Second, Teacher satisfaction was lower compared to the students is relatively. Teachers prefer 'various after school program' to 'using e-learning with Electronic board and Tablet PC'. However, learning effective of using FASTEL system was a 73.8% of teachers are effective is aware and had. Third, 35% Students recognized that are using the pastel system, frequently, On the other hand, the teachers are 60% and to recognize that there was. The reason doesn't the system to good use is slow wireless. Still, e-learning classroom infrastructure for satisfaction was high. Fourth, Teachers recognized students and the pastel system interaction than other e-learning system high. FASTEL System used in the most uncomfortable things on e-learning classroom Wireless Internet phenomena and lost content lacking, in order, I was told. Therefore, there is an urgent need to improve to include Wireless Internet speed improvements and various content added support, easy-to-use instructional tools Add support order selected.

• Journal of Science Education
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• v.34 no.2
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• pp.405-420
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• 2010

The purpose of this study was to contrive the specific teaching plans based on the frame of 2007 revised science curriculum for applying open-inquiry lesson in real education situation and to research the effects of open-inquiry lesson on the student's science-related attitude, science process skill, and to investigate instructing teachers' cognition about open-inquiry. For this study, two fifth grade classes were chosen, one class was the experimental group, who were taught by open-inquiry based lesson, and another was the comparative group, who were taught by traditional method based lesson. The findings of this study were as follows: After open-inquiry lesson, the experimental group students came to enjoy open-inquiry learning and had the positive thought about it. After open-inquiry lesson, the experimental group marked higher mean score than the comparative group in science-related attitude's field but didn't showed the meaningful difference. On the other hand, in science process skill's field, the experimental group showed the significant higher improvement than the comparative one, especially in the subordinate area of basic science process skill. Finally, teachers who instructed students open-inquiry lesson thought open-inquiry lesson is the self-directed problem solving learning which raise the student's science process skill and interest. And the teachers thought the obstacles to instruct open-inquiry lesson are the lack of the student's cognition about open-inquiry and the insufficient circumstance for open-inquiry lesson. Therefore the teachers argued that the prerequisite for settling open-inquiry lesson successfully is to develope open-inquiry lesson curricula and teaching materials.

• Ocean and Polar Research
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• v.26 no.4
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• pp.581-594
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• 2004

CREAHS II carried out an intensive hydrographic survey covering almost entire East Sea in 1999. Hydrographic data from total 203 stations were released to public on the internee. This paper summarized the results of water mass analysis by OHP (Optimum Multiparameter) method that utilizes temperature, salinity, dissolved oxygen, pH, alkalinity, silicate, nitrate, phosphate and location data as an input data-matrix. A total of eight source water types are identified in the East Sea: four in surface waters(North Korea Surface Water, Tatar Surface Cold Water, East Korean Coastal Water, Modified Tsushima Surface Water), two intermediate water types (Tsushima Middle Water, Liman Cold Water), two deep water types (East Sea Intermediate Water, East Sea Proper Water). Of these NKSW, MTSW and TSCW are the newly reported as the source water type. Distribution of each water types reveals several few interesting hydrographic features. A few noteworthy are summarized as follows: The Tsushima Warm Current enter the East Sea as three branches; East Korea Coastal Water propagates north along the coast around $38^{\circ}N$ then turns to northeastward to $42^{\circ}N$ and moves eastward. Cold waters of northern origin move southward along the coast at the subsurface, which existence the existence of a circulation cell at the intermediate depth of the East Sea. The estimated volume of each water types inferred from the OMP results show that the deep waters (ESIW + ESPW) fill up ca. 90% of the East Sea basins. Consequently the formation and circulation of deep waters are the key factors controlling environmental condition of the East Sea.