• Journal of Aquaculture
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• v.22 no.1
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• pp.42-50
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• 2009

Shrimp farming which is entirely conducted in outdoor ponds in the west coast of Korea has been suffered from mass mortality due to viral epizootics. Intensive indoor shrimp culture under limited water exchange can solve these problems of outdoor ponds including viral transmission from environment, pollution due to discharge of rearing water, low productivity and limited culture period. In this study, juvenile L. vannamei (B.W. 0.08-0.09 g) was stocked with $3,000-5,455/m^3$ in density in four raceway tanks (two $12.9\;m^2$, two $18\;m^2$ tanks) and cultured for 42 days with 2.7-3.4% of daily water exchange. Results from four tanks showed FCR of 0.79-1.29, survival of 38.2-48.0%, and yields of $2.49-4.22\;kg/m^3$ which is consistent with 12-20 and 8-14 times higher than those of commercial shrimp hatchery and outdoor pond in Korea, respectively. Concentrations of total ammonia nitrogen in all four tanks were 1.11-1.42 ppm in mean level and did not exceed 6.0 ppm (0.096 ppm of $NH_3$) which is still acceptable levels for shrimp growth. During the culture trial, concentration of $NO_2$-N rapidly increased from stocking, resulting in mean concentration of 18.45-22.07 ppm. It also exceeded 10 ppm over four weeks and maintained at 35-45 ppm for four days in all tanks, accounting for low survival of shrimp due to long-term exposure to high concentration of $NO_2$-N. Nevertheless, the results with survival rate over 38% from raceways which experienced the extreme $NO_2$-N levels suggests that under "biofloc system" white shrimp can acclimate to high $NO_2$-N concentration to some degree.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.2
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• pp.149-179
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• 2011

Statistics of aviation accident in Korea show that safety level of training flights is high. However, more than 80% of aviation accidents happen owing to human factors. And because most reasons of them are concerned with pilot error, it is very important for student pilots who will transport a lot of passengers to develop the knowledge of safety and abilities of risk management for preventing accidents. In this study, in order to investigate the Human Factors which affect safety in training student pilots for flight, verified the correlationbetween experiences of accident, the differences according to the experience level of training flight and the differences between college student pilots and ordinary student pilots on the basis of human factors that composes the SHELL models. For the study, Using SPSS 17.0, conducted Correlation Analysis, Analysis of Variance(ANOVA) and t-test. To sum up the result of this study, student pilot's ability and equipment in the cockpit are the important factors for safety when pilots are training flight. Also the analysis of the differences between human factors according to the characters of student pilots' groups shows that college student pilots are affected by immanent factors and organizational cultures. So far, there haven't been any accidents which is related with human casualties when training at the ATO(Approved Training Organization). But accidents can occur at any time and anywhere. Especially the human factors which comprises most of aviation accident have a wide reach and are impossible to be eliminated, therefore, it is best to minimize them. Because ATO is the starting point to lead the aviation industry of Korea, we will have to be aware of problems and improve education/training of human factors.

• Korean Journal of Construction Engineering and Management
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• v.17 no.4
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• pp.103-115
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• 2016

The 106 buildings of 200 meters' height or greater were completed around the world in 2015 (CTBUH, The Council on Tall Buildings and Urban Habitat). They beat every previous year on record, including the previous record high of 99 completions in 2014. This brings the total number of 200-meter-plus buildings in the world to 1,040, exceeding 1,000 for the first time in history and marking a 392% increase from the year 2000, when only 265 existed. South Korea recorded three completions during 2015 - improving slightly over 2014, in which it had one. This study focused on the fact that high-rise building development project risks have not reduced in Korea in spite of numerous studies and measures. And it attempted to examine whether existing studies and measures have been presented on the basis of the accurate analysis of existing studies and measures and classify and analyze the characteristics of each phase' s risk factors in the hope that its results would be one reference point as to the measure to prevent high-rise building development project risks in the future. A high-rise building development project is the high risk project as compared with the low-rise project. Because a high-rise development project takes long and is very sensitive to the changing environment. Therefore, in order to succeed the project it becomes necessary to effectively manage the risk involved in the process of the high-rise building development project. The result of this study can be used as the guideline to make the risk management system for the high-rise development project.

• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.85-98
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• 2013

In order to propose effective conservation management plan, this study verified ecological characteristics, humanities and Social characteristics. The research site is private property which is owned belonging to the Kim's of Gimhae that have long history. The study site is more than a thousand years old and was created for protecting from typhoon. There held the religious ritual what is called Dongsinje until 1960s. There have been protected and managed by the villagers. As the results of analysis, the area of windbreak are $12,392.69m^2$. The windbreak is dominated old years deciduous broad-leaved tree such as Zelkova serrata, Celtis sinensis, Aphananthe aspera. Around there were farmlands(52.1%), urbanized area(26.3%), forest area(16.6%). The vegetation communities of windbreak were classified by considering the dominant species and current status of forest. The forest types are following as; A. aspera community(I) which is using less pressure, Platycarya strobilacea-Carpinus coreana-Z. serrata community(II). Z. serrata community(III) which is using high pressure, Z. serrata-A. aspera community(IV), Z. serrata community(V) which is damaged under canopy trees. The windbreak was in good condition whereas, there were concerns the some wrong status was being undermined such as the wrong forest restoration projects in the past, the trails that is penetrating inside the forest, building up education facilities. Therefore, in order to restore the value of windbreak what is so called Suwol forest, we should improve the problems of forest ecosystem such as wrong management, forest fragmentation by facilities and decline in forest by lack of growing the next generation trees. In addition, we should remove excessive resting facilities and lead to passive use of forest. to improve the way of wrong management, moreover, we should close off he trails that is penetrating inside the forest for improving fragmentation. We should restore vegetation restoration and fostering the next generation trees for forest ecosystem. In order to restore unique of histo-cultural and ecological forest landscape, the next generation trees should be grown up that is the dominant species in Suwol forest. Moreover, as a results of comparing the between good vegetation communities and damaged vegetation communities, it is necessary to complementary planting for demeged vegetation communities, therefore there needs to 10.8 under canopy trees, 79.7 shrubs.

• Journal of Radiation Protection and Research
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• v.32 no.2
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• pp.89-96
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• 2007

Radiation safety managements in medical institutions are needed to protect certain radiation damages as a part of National Coalition. This study investigates the characteristics of self-efficacy that become the major factor on the knowledge, attitude, and behavior on the radiation safety management of radiation workers as an approach of educational aspects and analyzes the relationship between such factors to provide basic materials for improving the activity level of radiation safety managements. In order to implement the goal or this study, a survey was performed for 1,200 workers who were engaged in radiation treatments in medical centers, such as general hospital, university hospital, private hospital, and public health center for 42 days from July 23,2006. Then, the results of the analysis can be summarized as follows: 1. Average scores on knowledge, attitude, and behavior in the radiation safety management were presented as $75.76{\pm}11.20$, $90.55{\pm}8.59$, $80.58{\pm}11.70$, respectively. Also, the average score of self-efficacy was recorded as $73.55{\pm}9.82$. 2. Knowledge levels in the radiation safety management showed significant differences according to the sex, age, marriage, education, and experience. Also, males of married, older, highly educated, and largely experienced represented high knowledge levels. Attitude levels in the radiation safety management showed certain significant differences according to the type of medical centers in which private hospitals showed a relatively low level compared to that of high levels in university hospitals. Behavior levels in the radiation safety management also represented significant differences according to the age, marriage, education, experience, and types of medical centers. Factors in married, general hospital, older, highly educated, and largely experienced showed high behavior levels. In addition, the self-efficacy showed certain differences according to the marriage and types of medical centers. Factors in married and general hospital demonstrated high self-efficacy levels. 3. Relationship between knowledge, attitude, behavior, and self-efficacy on the radiation safety management showed statistical differences according to the relationship between the knowledge and the attitude, the knowledge and the behavior, the attitude and the behavior, the attitude and the self-efficacy, and the behavior and the self-efficacy. The relationship between the behavior and the self-efficacy was represented as r = 0.482, which was the strongest relationship in such factors. Also, the knowledge and self-efficacy didn't show certain relationships.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.538-543
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• 2008

Recently a nano-scale diamond is possible to manufacture forms of powder(below 100 nm) by new processing of explosion or deposition method. Using a sintering of nano-scale diamond is possible to manufacture of grinding tools. We have need of a processing development of coated uniformly inorganic to prevent an abnormal grain growth of nano-crystal and bonding obstacle caused by sintering process. This paper, in order to improve the sintering property of nano-scale diamond, we coated ZnO thin films(thickness: $20{\sim}30\;nm$) in a vacuum by ALD(atomic layer deposition) Economically, in order to deposit ZnO all over the surface of nano-scale diamond powder, we used a new modified fluidized bed processing replaced mechanical vibration effect or fluidized bed reactor which utilized diamond floating owing to pressure of pulse(or purge) processing after inserted diamond powders in quartz tube(L: 20 mm) then closed quartz tube by porosity glass filter. We deposited ZnO thin films by ALD in closed both sides of quartz tube by porosity glass filter by ALD(precursor: DEZn($C_4H_{10}Zn$), reaction gas: $H_2O$) at $10^{\circ}C$(in canister). Processing procedure and injection time of reaction materials set up DEZn pulse-0.1 sec, DEZn purge-20 sec, $H_2O$ pulse-0.1 sec, $H_2O$ purge-40 sec and we put in operation repetitive 100 cycles(1 cycle is 4 steps) We confirmed microstructure of diamond powder and diamond powder doped ZnO thin film by TEM(transmission electron microscope) Through TEM analysis, we confirmed that diamond powder diameter was some $70{\sim}120\;nm$ and shape was tetragonal, hexagonal, etc before ALD. We confirmed that diameter of diamond powders doped ZnO thin film was some $70{\sim}120\;nm$ and uniform ZnO(thickness: $20{\sim}30\;nm$) thin film was successfully deposited on diamond powder surface according to brightness difference between diamond powder and ZnO.

• Food Science and Preservation
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• v.16 no.5
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• pp.650-655
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• 2009

This study was conducted to measure the quality characteristics of rough rice during low temperature drying by using an experimental dryer and heat pump with a capacity of 150kg at four temperature levels of 20, 30, 40, and $50^{\circ}C$. The quality and proper drying temperature of rough rice was investigated by measuring variations in moisture content, crack rates, germination rates and cooked rice. Temperatures over $40^{\circ}C$ is considered a high-temperature area, and below $40^{\circ}C$ is considered a low-temperature area. The drying rates were 0.3, 0.6, 0.9, and 1.3%/hr, and the crack ratios were 0, 1.6, 6.8, and 24.2% at the drying temperatures of 20, 30, 40, and $50^{\circ}C$, respectively, which showed that the higher the drying temperature was, the higher the drying rate and crack rate was. Therefore, 20 and $30^{\circ}C$ were found to be appropriate drying temperatures for avoiding crack formation, and $50^{\circ}C$ was inappropriate. At $40^{\circ}C$, the operation methods needed to be modified to limit cracking, such as increasing the tempering time. Also, as the drying temperature increased, the germination rate decreased. Germination rates at 20 and $30^{\circ}C$ were suitable for using the rough rice as a seed, and those at 40 and $50^{\circ}C$ were over 80%, which is the minimum allowable percentage. In the sensory evaluation of cooked rice, the quality of appearance, taste, and texture varied as a function of drying temperature. When considering these factors, the cooked rice that was dried at 20 and $30^{\circ}C$ was better than the cooked rice dried at high-temperature. Consequently, in view of drying temperature and rates, the best conditions for drying rough rice were below $30^{\circ}C$ and below 0.6%/hr.

• Journal of Life Science
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• v.26 no.8
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• pp.911-920
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• 2016

Norovirus is the most common causative agent of acute gastroenteritis. This study was carried out to investigate molecular epidemiology of norovirus infections from outbreaks in Busan from 2012 to 2015. Total of 581 stool specimens were collected from diarrhea patients in outbreaks in Busan, 71 samples were resulted in positive to norovirus. The data were analyzed according to seasonality, patient, age and gender. Noroviruses were detected most frequently during the winter season from November (25.4%) to February (28.2%). The age group from teens was the most susceptible to norovirus infections. To obtain the molecular genetic information of norovirus, we performed sequencing analyses of the strains detected. Norovirus genotypes have been reported to show high genetic diversity. Four kinds of GI genotypes (GI-1, GI-2, GI-3, GI-5) and five kinds of GII genotypes (GII-1, GII-4, GII-5, GII-6, GII-17) were indentified in outbreaks in Busan. Other previous studies have shown that GII-4 is the most predominant circulating in Korea and worldwide. The most prevalent norovirus genotypes of each year were GII-6 in 2012, GII-6 in 2013, GII-4 in 2014 and GII-6 in 2015. Except for 2014, GII-6 genotype was the most prevalent and predominant in Busan. We described the epidemiological analysis of the noroviruses in outbreaks in Busan. The result of this study will contribute to update the epidemiological data and improve hygiene and public health via sustainable surveillance.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.2
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• pp.14-30
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• 2020

This study focuses on the fact that pictorial maps in the late Joseon Dynasty were conceptual diagrams with the place names perceived by the people at the time of their production. In this regard, targeting on five pictorial maps, the humanistic landscape characteristics of Pyongyang, which had cultural identities such as a historically old, commercial, and Pungnyu(appreciation for the arts) city, were derived as follows. First, the historic legitimacy of Pyongyang Castle was represented by ritual and religious facilities. They include 'Dangunjeon' and 'Gijagung' related to the nation founder, 'Munmujeong': the remains of Goguryeo, 'Sajikdan' & 'Pyongyanggangdan': the place of the national rites, Hyanggyo and Seowon: education & rite functions, Buddhism and Taoist facilities, 'Yongsindang', 'Sanshindang', and 'Jesindan': folk religion facilities. Gija-related facilities, which became symbols of Pyongyang due to the importance of Small-Sinocentrism and Gija dignity tendency, were distributed throughout Pyongyang Castle though, the facilities related to King Dongmyeong of Goguryeo and the spaces of religion praying for blessings are spread in Bukseong and on the riverside of Daedonggang each. Second, as a Pyongando Province's economic center, Pyongyang's commercial landscape was represented by logistics and transportation facilities. The Daedonggang River, which was in charge of transportation functions, had many decks such as 'Yangmyeongpo', 'Cheongryongpo' and 'Waeseongjin' and bridges, such as 'Yeongjegyo' and 'Gangdonggyo', which connected major transportation routes. The road network was created in Oeseong area to facilitate logistics transportation and management, and many warehouses named after the jurisdiction of Pyongyangbu were distributed near the roads and Provincial Offices of the main gates. In addition, it was characterized by the urban area systematically divided with hierarchical roads, 'Bukjangnim' of willow trees planted on the main entrance roads of Pyongyang Castle, a linear landscape created by 'Simnijangnim' consisting of mixed forests with elm trees. Third, Pungnyu City is realized by the distribution of amusement facilities. The riverside of Daedonggang adjacent to Naeseong exhibits characteristics of artificial landscape such as a canal leading to the inside of the castle, a docking facility with embankments, and a port with cargo ships anchored. However, Bukseong of the natural surroundings had numerous pavilions and platforms such as 'Bubyeongnu', 'Eulmildae', 'Choeseungdae', 'Jebyeokjeong' and engraved letters such as 'Cheongnyubyeok', 'Jangbangho'. 'Osunjeong', 'Byeogwolji', 'Banwolji' near 'Sachang', and 'Aeryeondang', built on the island of a square pond, created waterscape in Naeseong invisible from the Daedonggang, and for practical purposes, ponds and repeated willow vegetation landscape related to Gija were placed in the western rampart of Jungseong. In addition, 'Seonyeondong', a cemetery of Gisaeng, located near by Chilseongmun, was used as poem titles and themes by literary people, contributing to the creation of the Pungnyu image of Pyongyang.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.121-129
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• 2014

This study was carried out to investigate the quality characteristics of protein enriched fermented milk made with whey and soybean flour. Protein-enriched fermented milk was prepared as follows: Soybean flour was added before fermentation. No synthetic aroma was added. The fermentation starter culture was ABT-4 (Chr. Hansen). Whey protein was added after fermentation. Sensory evaluation indicated that sample containing soybean flour amount of 5% were better than other samples. The pH values and titratable acidities of stored protein-enriched fermented milk and fermented milk, respectively, were not remarkably different. Crude protein was more than 3 times higher in protein-enriched fermented milk (8.77%) than in fermented milk (2.49%). The crude fat content of protein-enriched fermented milk was not remarkably different compared to that of fermented milk. Dietary fiber was more than 2.7 times higher in protein-enriched fermented milk (1.67%) than in fermented milk (0.62%), and the free amino acid content was more than 14 times higher in protein-enriched fermented milk (37.9%) than in fermented milk (2.6%).