• Journal of Korea Planning Association
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• v.54 no.3
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• pp.75-90
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• 2019

As the 24-hour society arrives, human activities in daytime and nighttime urban spaces are changing drastically, and the need for new urban management policies is steadily increasing. This study analyzes the types and characteristics of Seoul's human dynamics using location-based big data and the results are summarized as follows. First, the pattern of human dynamics in Seoul repeats itself every 7 days. Second, the types of human dynamics in Seoul can be classified into five types, and each of type has its own unique time-series and local characteristics. Third, the degree of match between human dynamics and zoning system in urban planning legislation was highest in 'Type 1' residence pattern and low in other types. The following implications can be drawn from these results. First, This paper examined the methodology of analyzing the regional characteristics of Seoul through the human dynamics and obtained meaningful results. Second, This paper can derive reliable and objective pattern analysis results using Big data that reflect the overall population characteristics. Third, the scale of night-time activity in the urban space of Seoul was understood, and its distribution, patterns and characteristics identified.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.384-388
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• 2014

Air temperature has increased, while sunshine hour has decreased during the grain filling period of most rice cultivars (August to September) during the past 12 years from 2001 through 2012 in Korea. Climatic Productivity Index (CPI) has fallen because of the decreased sunshine hour and increased air temperature during the grain filling period, and the degree of reduction was greater with earlier heading. For stable rice production, we will need to delay the heading of rice as a cultivation measure against the future climatic trend. Grain yield showed no significant trend for past 12 years. However, the year to year change in grain yield showed a similliar pattern with that of CPI. Especially, a linear function relating rice yield to CPI explained approximately 63% of variation in grain yield with the heading date of August $11^{th}$ period.

• Membrane and Water Treatment
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• v.8 no.5
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• pp.499-515
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• 2017

The purpose of this study was to investigate membrane fouling caused by microalgal cells in submerged membrane systems consisting of polymeric and ceramic microfiltration membranes. In this study, one polymeric (flat-sheet, pore size: $0.2{\mu}m$) and two ceramic (flat-sheet, pore size: $0.2{\mu}m$ and cylindrical, pore size: $1{\mu}m$) membranes were used. Physical cleaning was performed with water and air to determine the potential for reversible and irreversible membrane fouling. The study results showed that substantial irreversible membrane fouling (after four filtration cycles, irreversible fouling degree 27% (cleaning with water) and 38% (cleaning with air)) occurs in the polymeric membrane. In cleaning studies performed using water and air on ceramic membranes, it was observed that compressed air was more effective (recovery rate: 87-91%) for membrane cleaning. The harvesting performance of the membranes was examined through critical flux experiments. The critical flux values for polymeric membrane with a pore size of $0.20{\mu}m$ and ceramic membranes with a pore size of $0.20{\mu}m$ and $1{\mu}m$ were ${\leq}95L/m^2hour$, ${\leq}70L/m^2hour$ and ${\leq}55L/m^2hour$, respectively. It was determined that critical flux varies depending on the membrane material and the pore size. To obtain more information on membrane fouling caused by microalgal cells, the characterization of the fouled polymeric membrane was performed. This study concluded that ceramic membranes with a pore size of $0.2-1{\mu}m$ in the submerged membrane system could be efficiently used for microalgae harvesting by cleaning the membrane with compressed air at regular intervals.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.887-891
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• 1995

Nutrient intake data collected by both dietary methods of the 24 hour recall method and the food frequency method from 538 middle school students were analysed to investigate any measurement errors occuring while using these methods. Measurement errors were observed both in terms of differences of average intake and consistancy from the two sources of data used. Wilcoxon signed ranks test was used to test the differences between the two average intakes and Speraman's rank order correlation coefficient was used to test consistancy. As a result, average intake value estimated from the food frequency method tended to be higher than that from the 24 hour recall method. The degree of overestimation varies from one nutrient to another. For instance, carotene showed not only the most significant differences in average intake but also showed the most incoisistancies between the two sets of data. This may imply the validity of nutrient intake as derived from different dietary survey methods varied from one nutrient to another, therefore the selection of dietary survey methods has to be made more cautiously in the case of certainnutrients.

• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.4
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• pp.3600-3610
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• 1974

Experimental work of batch-type dryer was conducted to develop its optimurm operating conditions by analyzing the major factors which affect the drying performance. A laboratory batch-type dryer was constructed and tested for various levels of heated-air rates, and depths of grain deposit. Tong-il rice variety having the initial moisture content of approximaely 23 per cent in wet basis was used for the experiment. The criteria selected for establishing the optimum operating condition were the drying performance rate, the thermal efficiency, and the operational cost of the dryer. The results of the study are summarized as follows: 1. The performance rate of dryer for a specific operating condition was defined as total amount of material dried per hour when the moisture content of grains in the upperlayer reaches to 16 per cent in wet basis. The optimum operating conditions as viewed in the rate of drying performance could be justified by functional realtionship between the depth of grain deposit and air flow rate. In other words, there was a definite depth of grain deposit for a given air-rate which make the dryer performance maximum. The optimum grain depth for the batch-type dryer with 3.3㎡ loading area and with the attached axial fan was about 35cm. 2. The thermal efficiency for the dryer was evaluated by the ratio of the latent heat required to evaporate the grain moisture to the heat input required to raise the ambient air-temperature to 40 degree centigrade. The optimum operating condition as viewed in term of thermal efficiency analyzed was that grater depth and lower air flow-rate may be desirable. This condition is contracted with the optimum condition as viewed by the dryer performance rate. 3. The annual operating cost of batch-type dryer was analyzed for different annual hour of use and for different operation condition. The optimum condition as viewed in terms of operating cost was almost identical to one as viewed in terms of dryer performance rate. Therefore, the most economical use of batch-type dryer for the same annual operating hours can be obtained when the dryer operated in the condition of maximum dryer performance rate. Increasing the annual operating hour may be desirable to cut down the dryer operation cost, since the annual hour of dryer use is much sensitive to the operating cost than any peractical conditions of dryer operation. 4. The most desirable operational condition as justified by combining all the criteria, dryer performance rate, thermal efficiency and annual operating cost, could be concluded to operate the dryer in the condition of maximum performance rate. The condition in general is identical to the lowest operation cost for a given annual operating hour.

• Korean Business Review
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• v.19 no.2
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• pp.207-230
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• 2006

The study which it sees probably is the tourist' from the tourist resort, a emotional response and the change of stay hour and the follows in crowding perceived degree and it examines it does. In order to achieve the purpose of this study, carried out literature study of a related field and set up a study model. We used one method. The first method was directly distributing questionnaires to tourist' by use of one researcher who has been trained in tourist site, in order to confirm hypothesis established according to a theoretical background. And as the site of study, chose Mureung Valley which are located in the East Sea region which is one of the largest domestic vacation destinations. Through these methods, we were able to obtain participation of 450 people from across the country. Using 408 responses(42 responses removed). we derived statistics by means of Win SPSS Version 10.0 statistics program package. The analysis results ara as follows: First, Perceived Crowding affects tourists' Emotional Response and the Stay hour change. Specially, perceived Crowding is from in the Emotional Response factor it is joyful with there is relationship of excitation relationship effect. Second, There is relationship of effect even to sentimental reaction and stay hour change. This also is from in the Emotional Response factor it is joyful with there is relationship of excitation relationship effect. Finally, we discuss the results of analysis and suggest research limitation and future and future study.

• Journal of the Korean Dietetic Association
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• v.6 no.2
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• pp.136-147
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• 2000

The aim of this research was to examine the management practices related to foodservice.clinical nutrition service provided by hospital foodservice operations. A survey of 30 hospital food nutrition service departments was undertaken and detailed information was collected from each, including surveys of 176 dietitians and 30 foodservice managers. Statistical data analysis was completed using the SAS/win 6.11 package for descriptive analysis and t-test. The results of this study can be summarized as follows : Out of 30 hospitals, 73.3%(22) were directly operated and 26.7%(8) were under contract foodservice management. Licensed number of beds were 768.7, with an average length of 11.4 days. The general characteristics of the dietitians were that 49.4% were aged between 25-29, and 60.8% were ordinary dietitians. 76.7% had bachelor's degree, 15.9% with master's degree and 7.4% were college graduates. Most hospital dietitians had internship training and 35.2% took a training course of 6 to 12 months. The average space of kitchen was 452.52 $m^2$, with 133.63$m^2$ for modified diet space and 18.13$m^2$ for nutrition counselling room space. The total number of normal meals was 1,255.47, with 502.93 of modified meals. The average calorie of normal meals was 2,145.04kcal, with 91.9g of protein contained in normal meal. The total food waste was 351.40kg. An average monthly cost for disposing food waste was 745,171.67 won. 83.3% of the kitchens were on the 1st basement and only 66.7%(20) of 30 hospitals had its own nutrition counselling room. 80% used dishwashers and 66.7% had an exclusive elevator for delivering meals. 80.0% of hospitals used centralized delivery service. 90% had established an area for hygiene division, 70% used dry zone within the dishwashers for sterilization, 66.7% provided spoon and chopstick, and 100% used dish cover. As means of food waste treatment, most hospitals(56.7%) used animal feed by contracters, followed by means of collection by contracters(30%) and in-house high speed fermentation machines(13.3%). It was found that only 33.3% hospitals regularly checked temperatures of the meals given to patients. Total productivity index was 3.72(meals/hour) in average, with an average productivity index for normal diet of 5.41. Average productivity index for modified diet was 4.62. Productivity indices for patient meals and clinical nutrition were 5.01(meals/hour) and 1.12(cases/hour) respectively and hospitals under self-operated foodservice management received higher points on clinical nutrition productivity index(P<0.01) than hospitals under contract foodservice management.

• Journal of Families and Better Life
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• v.7 no.2
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• pp.15-30
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• 1989

This study deals with the following problems about leisure activity of young people and leisure guidance of mothers, (1) Leisure activity of children by the independent variables, (2) Leisure guidance of mothers by the independent variables. (3) The relation between leisure guidance of mothers and leisure activity of young people. This research used the questionaire survey. The subjects were 830 couples of mother and pupil (pupils of 4, 5 and t grades in six primary school in Kwang-Ju city). The statistics used for data analysis were percentage, t, F-test, X2. The results of this study are summarized as follows; (1) Boys and girls average leisure hours: week days…2 hour, saturday…3 hours, Sunday and holiday…4.5 hours, the school vacation…6.2 hours. And leisure activity showed the significant difference in sex, age, educational level, family form (p 0.001, p 0.05, p 0.010). Generally, they had social & amusing leisure activity. And a hindrance cause of leisure activ ty is due to hard working in learning practice. (2) The necessity of leisure activity showed higher in the aged mother and high educated mother, lower in the poor family. And guidance content showed the significant difference in sex of children(p 0.001), educational level of parents(p 0.05). Actually mothers wanted intellectual leisure activity. (3) The relation between the leisure activity pattern desired by leisure activity of mothers and children pattern showed that mothers demanded the various patterns, but children wanted social & amusing leisure activities mainly. Only children's patterns agreed with mothers in the artistic, intellectual, activities on Saturday and during the vacation. And the relation between mothers satisfaction degree in the leisure activity of children and children's satisfaction degree showed the significant difference (p 0.05). Children's satisfaction degree is high, irrespective of mothers satisfaction degree.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.217-226
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• 2013

PURPOSES : Under the capacity conditions with balanced approach flows, roundabouts give less delay than existing signalized intersections; however, flows over 450 vehicles/hour/lane with unbalanced approach flow conditions, roundabouts efficiency drops due to the short time difference between the critical gap and the follow-up headway. The purpose of this study is developing a roundabout Signal Metering operation method by considering approach lanes degree of saturation. METHODS : A four-way-approach with one-lane roundabout is selected to compare the Signal Metering performance for the case of 16 different unbalanced flow conditions. Based on these traffic conditions, the performance is evaluated for 64 different cases of Signal Metering combinations by using SIDRA software. A degree of saturation(V/C ratio) sum for two adjoined approaches is used for the performance index of choosing Metered Approach and Controlling Approach. RESULTS : When the V/C ratio sum is 0.29~0.81 and Metered Approach flow is less than Controlling Approach flow, the average delay saving per vehicle is about 7 seconds; however, after this rage the delay saving decreases gradually until the V/C ratio sum reaches around 1.0. The range of V/C ratio sum 0.93~1.09 provides average delay saving per vehicle about 3 seconds. In case of V/C ratio sum is grater than 1.0 and the flows of Metered Approach is grater than Controlling Approach, the average delay per vehicle increases 3~11 times respectively. CONCLUSIONS : As expected, the Signal Metering provides substantial improvements in delay saving for the case of V/C ratio sum is 0.3~1.0 under the traffic flow conditions of Metered Approach is less than Controlling Approach.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.290-296
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• 2003

The waterfront the house it falls to empty, it sprouts and un-waterfront to beggarly more view, showing a high satisfactory degree from elements which of the house environment back is diversified, there is to immigration plan of future and the waterfront the area is high and it was visible the degree which is probably. Also the waterfront against to the development of the area the rate where the development recognizes a necessity will be high, it will be high, it will be pay scheduled one expense from even and the river or the coast the line will choose to the view is visible the answer back own house was many. Here upon the waterfront to development of the which indispensability or development hour (1)sublation of the development which is insensitive, (2)the fixed quantity development which hits to demand and supply, (3)after developing the continuous civil official, (4)the environment friendship development back is indicated with consideration fact.