• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.93-100
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• 2011

Maintenance of adequate soil water potential during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement within and below the rooting zone can facilitate optimal irrigation scheduling aimed at minimizing the adverse effects of water stress on crop growth and development and the leaching of water below the root zone which can have adverse environmental effects. The objective of this study was to evaluate the feasibility of using a portable irrigation controller with an Watermark sensor for the cultivation of drip-irrigated vegetable crops in a greenhouse. The control capability of the irrigation controller for a soil water potential of -20 kPa was evaluated under summer conditions by cultivating 45-day-old tomato plants grown in three differently textured soils (sandy loam, loam, and loamy sands). Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30 cm depths. Even though a repeatable cycling of soil water potential occurred for the potential treatment, the lower limit of the Watermark (about 0 kPa) obtained in this study presented a limitation of using the Watermark sensor for optimal irrigation of tomato plants where -20 kPa was used as a point for triggering irrigations. This problem might be related to the slow response time and inadequate soil-sensor interface of the Watermark sensor as compared to a porous and ceramic cup-based tensiometer with a sensitive pressure transducer. In addition, the irrigation time of 50 to 60 min at each of the irrigation operation gave a rapid drop of the potential to zero, resulting in over irrigation of tomatoes. There were differences in water content among the three different soil types under the variable rate irrigation, showing a range of water contents of 16 to 24%, 17 to 28%, and 24 to 32% for loamy sand, sandy loam, and loam soils, respectively. The greatest rate increase in water content was observed in the top of 10 cm depth of sandy loam soil within almost 60 min from the start of irrigation.

• Journal of Chest Surgery
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• v.29 no.4
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• pp.373-380
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• 1996

Prevention of thromboembolism is the most important task in the development of bioconpatible small caliber artificial vascular graft. In normal vessels, vascular endothelial cells maintain homeosatsis by secreting numerous factors. The aim of this study is to develope a method which Improves biocompatibility of small caliver polyurethane graft using endothelial cell culture technique, and ev luate the efTectiveness of extracelluar matrix for endothelization which was produced by cultured fibroblast. Methods ; Multiporous polyurethane tube of 3 mm diameter, 0.3 mm thickness was manufactured for vascular graft. Three mongrel dogs were intubated and internal jugular veins removed. Extracelluar matrix produced by cultured flbrobast which was obtained from dog's internal jugular vein were coated to the polyurethane graft. Then, endothelial cells extracted from Jugular vein were cultured and fixed on the extracelluar matrix layer of vascular graft. Endothelial cell coated vascular grafts were implanted to the carotid arteries of experimental dogs as interposed autograft. Implanted grafts were removed after 3 and 6 weeks. As a control, PTFE graft was interposed on carotid artery. These experiments demonstrated that extracelluar matrix produced by fibroblast can afford a base for endothelial cell linings of polyurethane graft. Although thrombosis were developed on autografted en othelial cell coated graft, 33% opening was noticed, and showed less adhesion to adjacent tissue layer. These findings suggest that fiboblast produced extracelluar matrix which can be used for edothelial cell lining vascular graft, and by improving the cultured endothelial cell function, there will be a new modality for reducing thrombosis on small vascular graft.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.18-39
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• 2016

The study pertains to reviewing and discussing of the master plan of the main buildings in the palaces of Joseon Dynasty regarding on a Feng Shui concept that has been implemented on the palace axis that is originated from the main mountain. Gyeongbokgung (景福宮) Palace is located on the northwest coner of Hanyang (漢陽) and on the tip of the main mountain which is in contrast a quite distinguishable from the location of the Fobidden city in Beijing located in the middle of a vast basin. Changdeokgung (昌德宮) Palace as well is also located on the tip of Eungbong (鷹峯), a part of Samkaksan (三角山) mountain, of which the locations were designed for the palaces to receive the benevolent force from the main mountain. The same concept was also applied to appointing the ideal location of the maJor buildings such as Jungjeon (正殿: The throne hall), Pyunjeon (便殿: The king's office) and Chimjeon (寢殿: The king and queen's residence) in the palace that must receive the benevolent force from the qui stream also originated from the main mountain, as such that the buildings have in close relationship with the king. Amisa (蛾眉砂) had been considered as an important geographical milestone of the estate where the palace is located, especially as the guiding landmark for other buildings that must be on the land axis. The land axis with the Amisa as the starting point attributed the Feng Shui as an important measure that determines the location and the shape of other buildings. The buildings location was appeared as having the conceptual buildings location as 'front office-back bedroom building (前朝後寢)' and 'three gates-three sectors (三問三朝)' as per the Rites of Zhou (周禮). On both palaces, Amisa is located on the benevolent point of the land, and the king's bed room buildings are located near the Amisa. The main offices were located on the south of the king's bed room buildings. By practicing this type of concept, consequently the king can receive the pure benevolent force first. In the case of the clearly distinguished locations of the buildings in Gyeongbokgung Palace, Chimjeon, Pyunjeon and Jungjeon were located on the same main qui stream. However, in Changdeokgung Palace where scattered qui stream is observed, the buildings are located on the scattered qui stream. The study found that the type of location of Jungjeon receives least amount of benefit from the Feng Shui but reflects primarily the king's authority rather than order and formality of the space.

• Journal of The Korean Association For Science Education
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• v.38 no.2
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• pp.259-271
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• 2018

This study examined the effect of the SSI argumentation program based on social and emotional learning(SEL). The program consisted of 3 stages: (1) express their own feelings about SSI, identify the issues of SSI, and define a goal; (2) think of many possible solutions and envision results through argumentation; (3) select the best solution and make a decision based on warrants, data, and rebuttals. In each stage, the social-emotional strategies of self-awareness, self-management, social-awareness, relationship-management, and responsible decision making were used. Seventeen preservice biology teachers participated in this study during one semester dealing with four socioscientific issues. The results indicated that the preservice teachers, as time went on, became accustomed to expressing identifiable rebuttals, dispute talk, and asking questions. At the first SSI argumentation, argumentation mainly consisted of cumulative talk with no rebuttals, representing level 2 argumentation. Level 3 argumentation represented rebuttals that were implicit and weak, with cumulative talk. In level 2 and 3 argumentation, the preservice teachers represented understanding of others and compassion for self and others. Level 4 argumentation had rebuttals that were explicit, asking critical questions of the opposite sides. In addition, level 5 argumentation represented more than two controversial points with several instances of dispute talk. In levels 4 and 5, the preservice teachers became actively engaged in communication, inquiry self with others, managing vulnerability and negotiation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.1
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• pp.21-30
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• 1985

The tension leg platform (TLP) is a kind of compliant structures, and is also a type of moored stable platform with a buoyancy exceeding the weight because of having tensioned vertical anchor cables. In this paper, among the various kinds of tension leg structures, Deep Oil Technology (DOT) TLP was analyzed because it has large-displacement portions of the immersed surface such as vertical corner pontoons and small-diameter elongated members such as cross-bracing. It also has results of hydraulic model tests, comparable with theorectical analysis. Because of the vertical axes of symmetry in the three vertical buoyant legs and because there are no larger horizontal buoyant members between these three vertical members, it was decided to develop a numerical algorithm which would predict the dynamic response of the DOT TLP using the previously developed numerical algorithm Floating Vessel Response Simulation (FVRS) for vertically axisymmetric bodies of revolution. In addition, a linearized hydroelastic Morison equation subroutine would be developed to account for the hydrodynamic pressure forces on the small member cross bracing. Interaction between the large buoyant members or small member cross bracings is considered to be negligible and is not included in the analysis. The dynamic response of the DOT TLP in the surge mode is compared with the results of the TLP algorithm for various combinations of diffraction and Morison forces and moments. The results which include the Morison equation are better than the results for diffraction only. This is because the vertically axisymmetric buoyant members are only marginally large enough to consider diffractions effects. The prototype TLP results are expected to be more inertially dominated.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.145-157
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• 2004

The cycle length design model of the Korean traffic responsive signal control systems is devised to vary a cycle length as a response to changes in traffic demand in real time by utilizing parameters specified by a system operator and such field information as degrees of saturation of through phases. Since no explicit guideline is provided to a system operator, the system tends to include ambiguity in terms of the system optimization. In addition, the cycle lengths produced by the existing model have yet been verified if they are comparable to the ones minimizing delay. This paper presents the studies conducted (1) to find shortcomings embedded in the existing model by comparing the cycle lengths produced by the model against the ones minimizing delay and (2) to propose a new direction to design a cycle length minimizing delay and excluding such operator oriented parameters. It was found from the study that the cycle lengths from the existing model fail to minimize delay and promote intersection operational conditions to be unsatisfied when traffic volume is low, due to the feature of the changed target operational volume-to-capacity ratio embedded in the model. The 64 different neural network based cycle length design models were developed based on simulation data surrogating field data. The CORSIM optimal cycle lengths minimizing delay were found through the COST software developed for the study. COST searches for the CORSIM optimal cycle length minimizing delay with a heuristic searching method, a hybrid genetic algorithm. Among 64 models, the best one producing cycle lengths close enough to the optimal was selected through statistical tests. It was found from the verification test that the best model designs a cycle length as similar pattern to the ones minimizing delay. The cycle lengths from the proposed model are comparable to the ones from TRANSYT-7F.

• Journal of Korean Home Economics Education Association
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• v.15 no.3
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• pp.75-88
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• 2003

The purpose of this study was to grasp the instruction type and the school hours allocations for the$\ulcorner$Technology and Home Economics$\lrcorner$united on the Korean education course revised seventhly and to offer the basic materials for the efficient curriculum implementation type through proving that how are the degree of studying load of students, interest, necessity, and satisfaction and whether those are affected or not. The subject of this survey were 297 students at first grade in boys high school, girls high school, and coeducational school located in the Chungnam-Province, Taejeon Megalopolis City. The period of this survey was from 30th Sep. 2002 to 5th Oct. 2002. The results were as follows; 1. In the implementation type of the curriculum. whole charge teaching was twice times as much as alloted teaching. 2. About half of the students(54.2%) recognized that the burden of study was less than before. More two third of students(72.4%) were satisfied with implementation of subject. The coeducational school and girls high school students were being more satisfied than the boys high school students, and students educated by alloted teaching were more satisfied. 3. The field of Home Economics was higher than the field of Technology in the degree of interest and necessity for$\ulcorner$Technology and Home Economics$\lrcorner$curriculum contents. 70.8% of the respondents was satisfied for the content materials. The coeducational school and the girls high school students were more satisfied with the course content than boys high school students.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.161-167
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• 2007

In this study, we constructed and tested retrovirus vectors designed to express the human thrombopoietin gene under the control of the tetracycline-inducible promoters. To increase the hTPO gene expression at him-on state, WPRE sequence was also introduced into retrovirus vector at downstream region of either the hTPO gene or the sequence encoding reverse tetracycline-controlled transactivator (rtTA). Primary culture cells (PFF, porcine fetal fibroblast; CEF, chicken embryonic fibroblast) infected with the recombinant retrovirus were cultured in the medium supplemented with or without doxycycline for 48hr, and induction efficiency was measured by comparing the hTPO gene expression level using RT-PCR, western blot and ELISA. Higher hPTO expression and tighter expression control were observed from the vector in which the WPRE sequence was placed at downstream of the hTPO (in CEF) or rtTA(in PFF) gene. This resulting tetracycline inducible vector system may be helpful in solving serious physiological disturbance problems which have been a major obstacle in successful production of transgenic animals.

• Journal of The Korean Association For Science Education
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• v.31 no.1
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• pp.78-98
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• 2011

The purpose of this study was to analyze elementary school students' interpretation of data characteristics by cognitive style. Participants were elementary students in sixth grade who can use integrated inquiry process skills. The students were divided into two groups, analytic cognitive style and wholistic cognitive style according to their response to Cognitive Style Analysis. They performed scientific interpretation of data activity. To collect data for this study, participants recorded the result on scientific interpretation of data activity paper and researcher recorded the situation on videotape and interviewed with participants after the end of interpretation of data to get additional data. And the findings of this study were as follows: First, the study analyzed interpretation of data characteristics by the operator regarding different situations of interpreting data according to cognitive style. For example, in the intermediate state, analytic-cognitive style students showed high achievement in identifying variables, and wholistic-cognitive style students were active in using prior knowledge to interpret data. Second, the result of analysis on the direction of interpreting data and preference for data types in interpreting data activities according to cognitive style are as follows: Wholistic-cognitive style students showed relatively high perception of information through the top-down approach. On the other hand, analytic-cognitive style students usually used the bottom-up approach gradually expanding detailed information to the scientific question-related answer and showed a preference data of the table type. Through the result, this study aimed to help establish a data interpretation strategy for learners to solve problems based on understanding of interpretation of data characteristics according to learners' cognitive style, and purposed the instruction design suggesting the data requiring various data interpretation strategies to develop learners' data interpretation ability.

• Food Science and Preservation
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• v.14 no.4
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• pp.414-418
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• 2007

The physicochemical characteristics and sensory properties of Deodeok wine, formed by leaching of Deodeok at room temperature for 180 days, were investigated over the following range of Deodeok levels: 10, 15 and 20% (all w/v). The higher the level of Deodeok, the greater were the final values of total sugars, reducing sugars, total polyphenols, and crude saponins. The Hunter's b-value (yellowness) of Deodeok wine varied markedly with Deodeok levels, and yellowness was highest in Deodeok wine containing 20% (w/v) Deodeok. Non-volatile compounds, that form the basis of the liquor tax law, were 0.64, 1.38 and 2.11% (all w/v), respectively, at day 160. Of these values, that of 2.11% (w/v), the level of non-volatile compounds in Deodeok wine containing 20% (w/v) Deodeok, was in accord with the liquor tax law (that requires this figure to be 2.0%). Sensory evaluation showed that Deodeok wine containing 20% (w/v) Deodeok was superior to the other wines tested.