• Food Science and Preservation
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• v.6 no.2
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• pp.137-142
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• 1999

Physicochemical properties were evaluated for stored garlic bulbs during 9 months under different conditions, such as low-temperature condition (3${\pm}$1$^{\circ}C$, 80${\pm}$5% RH, LT), pit-temperature condition (9${\pm}$6$^{\circ}C$, 80${\pm}$5% RH,PT) and ambient-temperature condition (14${\pm}$11$^{\circ}C$, 67${\pm}$5% RH, AT). The internal sprout development was more significant in pit and ambient conditions than in low temperature and thus certain means for sprout control is required for long-term storage of garlic bulbs under such conditions. The rates of rotting and weight loss were appreciable especially after 7 months of storage (next March) in the order of PT, AT and LT, when external sprouts were observed in PT and AT. Moisture content of stored samples were relatively constant in LT until next May, but that in W and AT was significantly reduced after next January. Total sugars showed a decreasing tendency with the prolonged period, whereas an apparent increase was found in the contents of reducing sugar and vitamin C along with external sprouting of garlic bulbs from the 7th month of storage (next March). Based on the results that around March is a limiting point in garlic storage at such conditions from the physiological and physicochemical points of view, improved storage condition should be applied to overcome the storage barrier.

• Journal of The Korean Association For Science Education
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• v.18 no.2
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• pp.245-256
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• 1998

In this study, we discussed about the implications of the idealization, which take an important role in physics, to the physics education. First, understanding of the idealization help the physics learning itself. This is because that various types of idealizations are included in the physics terms and concepts, derivation processes of physics laws and formulas, and explanation of natural phenomena and problem solving activities. Second, understanding of the idealization can help the application of the physics world to the real world. That is, by understanding the extent and the limit of idealization used in physics world, physics students can understand the discrepancies between the real world and the physics world. And also, by modifying or eliminating the idealization, students can extend the extent of understanding about how predictions based on the idealization used in the physics world will change. To do this, we suggested the application of computer simulation program in physics laboratories. Third, idealization take an important role in the inquiry learning for students' originality. The activities of identifying or controlling the variables, as one of the principal factors of scientific inquiry, need the appropriate establishment of the ideal conditions. And to analyze the limiting case or practice the thought experiments for understanding the impossible situation in the real world, ideal conditions also are needed. This study discussed above three aspects with various concrete examples and, with Park et al.'s study (Park et al., 1998), present the theoretical basis for the study of students' and teachers' understanding the idealization.

• Journal of Korea Water Resources Association
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• v.35 no.5
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• pp.525-539
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• 2002

Effects of Yongdam Dam discharge conditions on water quality of the Keum River and Daechung Lake inflow were analyzed for various scenarios using WASP5 water quality model. Three different groups of scenarios were tested: 1) Two different weather conditions; the lowest flow year and the highest flow year since the beginning of Daechung Dam operation in 1981, 2) Fine discharge flow rates; 5.4, 8.9, 12.4, 16.4 ㎥/s and field observed flow during the study period, 3) Three conditions of discharge water quality; first grade, second grade by Korean water quality standard and field observed water quality. Effect of changes in Yongdam Dam discharges was greater for dry year. The increase of discharge from the Yongdam Dam will improve water quality of downstream areas only when the water quality of the discharge is equal or better than that of downstream areas. Field observed water qualify data show that BOD concentrations are lower than first grade level but TN and TP concentrations are exceeding 5th and 3rd grade level in Korean standard, respectively. Considering that nutrient control methods in watershed areas of Yongdam dam are limited, it is expected that nutrient concentrations from Yongdam Dam discharge will be higher than 2nd grade water quality standard level. Therefore, it would be important to develop practical management strategies in the watershed area of Yongdam Dam based on field conditions for conservation of water quality in downstream areas.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.3
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• pp.107-113
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• 1989

The purpose of this study is to compare the results of shear-deformation of saturated sand under the 3 dimensional stress with the results of simple torque-shear test already reported, Japaness standard sand, Toyoura sand, was chosen as test sample and the equipments of the department of soil mechancis laboratory of Nihon University were used. The conclusions obtained are as follows. 1). The friction angle of sand (${\phi}$) is proportional to the density regardless of the condition of stress-strain. This is because of the reason that the lower the cell pressure becomes, the larger the volume changes in case of the same density. 2). The value of ${\varphi}$ are variable according to the condition of stress-strain in the same density, and ${\phi}_dTS$ is larger than ${\phi}_dPS$ and ${\phi}_dTC$ when cell pressure is low. 3). ${\phi}_dPS$ is larger then ${\phi}_dTS$, under the same denstiy and same cell pressure. Thus the shear strength of sand is decided according to the condition of stress-strain 4). the relationship between the stress ratio (q/p) and strain increment ration in the plane strain test is linear regardless of the density and the cell pressure of the test sample.

• Korean Journal of Weed Science
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• v.15 no.3
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• pp.197-205
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• 1995

The objectives of the present study were to find out 1)the differences in growth of radish under foggy and non-foggy condition, 2)the weed competition between radish and major upland weeds including Echinochloa crus-galli, 3)difference in response of radish to herbicide and weed, and finally 4)the fundamental data for the establishment of radish weed control system under locational foggy regions. The research was carried out by tray in greenhouse equipped with Auto Foggy System(SAE KI RIN Co.) and results were summarized as follows. 1. Plant height and shoot fresh weight of radish cultivars(long skirt, delicious altari, green mascot) were not different at the early growth(8 to 38 days after seeding), but increased at 55 days after seeding under foggy condition. Root fresh weight increased only in green mascot cultivar tinder foggy condition. Chlorophyll contents were higher in all the cultivars of radish under foggy condition. 2. Plant height and shoot fresh weight increased at 0 and 20 days of weed competition under foggy condition. Root fresh weight increased at 0, 20 and 35 days of competition under foggy condition. Above 50 days-competition, there was no difference between foggy and non-foggy condition. 3. Napropamide, alachlor and linuron did not show any differences in plant height and shoot fresh weight between foggy and non-foggy condition. Molinate reduced the root fresh weight at 65 days after seeding tinder foggy condition. 4. No difference in weeding efficacy by any herbicides tested was found tinder foggy condition. Weeding efficacy of Aeschynomene indica was reduced under foggy condition.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.999-1012
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• 2017

Theoretical, empirical and numerical methods are used to evaluate the rock load due to tunnelling. Theoretical and empirical methods do not consider ground conditions, tunnel shape, and construction conditions. However, through numerical analysis, it is possible to analyze the displacement and stresses around tunnel due to its excavation, and evaluate the rock load considering ground and construction conditions. The stress transfer ratio(e) which is defined as a ratio of the difference between the major and minor principal stresses to major principal stress is used in order to understand the stress transfer effect around the tunnel excavation using numerical analysis results. The loosend area around tunnel periphery was found based on this approach. The difference of rock load from stress transfer effect was found according to the ground grade. From comparison, rock load obtained from stress transfer effect (e = 10%) were somewhat larger than the results obtained from the critical strain method, but smaller than those obtained from theoretical and empirical methods. The stress transfer effect approach considers the ground condition, tunnel shape; therefore, it can be applied to evaluate the rock load in concrete lining design.

• Journal of Korea Water Resources Association
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• v.54 no.12
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• pp.1305-1316
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• 2021

In this study, a new empirical formula for 2D transverse dispersion coefficient was developed using the results of previous tracer test studies, and the performance of the formula was evaluated. Since many tracer test studies have been conducted under the conditions where the width-to-depth ratio is less than 50, the existing empirical formulas developed using these imbalanced tracer test results have limitations in applying to rivers with a width-to-depth ratio greater than 50. Therefore, in order to develop an empirical formula for transverse dispersion coefficient using the imbalanced tracer test data, the Synthetic Minority Oversampling TEchnique (SMOTE) was used to oversample new data representing the properties of the existing tracer test data. The hydraulic data and the transverse dispersion coefficients in conditions of width-to-depth ratio greater than 50 were oversampled using the SMOTE. The reliability of the oversampled data was evaluated using the ROC (Receiver Operating Characteristic) curve. The empirical formula of transverse dispersion coefficient was developed including the oversampled data, and the performance of the results were compared with the empirical formulas suggested in previous studies using R². From the comparison results, the value of R² was 0.81 for the range of W/H < 50 and 0.92 for 50 < W/H, which were improved accuracy compared to the previous studies.

• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.22-31
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• 2019

The application of BIM that can manage and integrate information generated during the entire life cycle of buildings in domestic and overseas construction projects is becoming active. When BIM is utilized in the construction phase, it can shorten the construction period, reduce the occurrence of reworks and improve collaboration capability. However, there are limitations in applying BIM to the construction phase due to the insufficient definition level of domestic BIM guidelines and inadequate design standards. In this regard, this study developed BIM model requirements checklist for the application of BIM in the construction phase. To develop the checklists, 21 domestic and overseas BIM guidelines, three public construction projects and four private construction projects to which construction BIM was applied, were analyzed. Based on the guidelines and cases, a total of 62 construction BIM model requirements (31 model objects and 31 attribute rules) and proposed construction BIM model requirement checklists by dividing the 61 requirements according to the requirement and purpose for utilization were identified. It is expected that the practical applications of the checklists proposed in this study will improve the level of BIM model in construction phase. In addition, this study has its significance as a basic research that can be used in the development of standardized guidelines for BIM model in construction phase from academic aspects.

• Science of Emotion and Sensibility
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• v.24 no.4
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• pp.3-16
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• 2021

The attribution of human traits, emotions, and intentions to nonhuman entities such as robots is known as anthropomorphism. Two studies were conducted to check whether human-robot interaction is affected by anthropomorphic framing of robots. In Study 1, participants were presented with pictures of robots that varied in human similarity in appearance. According to the results, uncanny feelings toward a robot increased with the higher levels of human similarity. Furthermore, as the level of mind attribution increased, participants tended to attribute more humanlike abilities to nonhuman agents. In Study 2, a robot was described as either a machine-like robot or a humanlike robot in a priming story; then, it was examined whether significant differences exist in mind attribution and moral care. The participants tended to perceive robots as more humanlike in the mind attribution when anthropomorphism was used in a robot's behavior, according to the findings. Furthermore, in the condition of increased anthropomorphism, a higher level of moral care could be observed compared with that in the other condition. This means that humanlike appearances may increase uncanny feelings, whereas anthropomorphic attribution may facilitate social interactions between humans and robots. Limitations as well as the implications for future research are discussed.

• Korean Journal of Culture and Social Issue
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• v.23 no.1
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• pp.1-24
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• 2017

This article aimed to test whether specific social values (i.e., achievement vs. benevolence) could cause changes in decision making on bio-ethical issues. Study 1 investigated value preferences among young Korean college students according to Schwartz's (1992) model of social values. According to the results, the preference for achievement value was correlated negatively with the preference for benevolence value. In Study 2, following a sentence completion task which was conducted to trigger specific values, the participants had to indicate their ethical decisions regarding animal experiment, euthanasia, organ transplantation, biotechnology, sex selection and human cloning, Irrespective of the value priming (achievement vs. benevolence), there were more utilitarian decisions about animal experiment, euthanasia and organ transplantation. In contrary, there were more deontological decisions about sex selection and human cloning. Study 3 introduced a word completion task to assess implicit value preferences. The results showed that the participants with implicit preferences for the benevolence value in the condition of benevolence value priming were more frequently against animal experiments and organ transplantation than those with implicit value preferences for the achievement value. Social values are discussed for understanding one's bioethical decision making.