• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1492-1503
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• 2015

This study evaluated the combination effect of various freezing and thawing techniques on the quality and nutritional aspects of onions. Onions were frozen by natural air convection freezing (NCF), air blast freezing (ABF), and liquid nitrogen freezing (LNF). Onions were frozen for 76 min by NCF, 9 min by ABF, and 9 min by LNF. The freezing treatment was stopped when the core temperature reached $-12^{\circ}C$ for NCF and ABF, and $-120^{\circ}C$ for LNF. Frozen samples were thawed through natural air convection thawing, running water thawing, sonication thawing (ST), or microwave thawing. The quality and nutritional aspects of frozen-thawed onions were evaluated by measuring thawing loss, pH, texture, water content, color, and SEM image. ST was found to cause the least loss in onion sample among the tested thawing methods, whereas the freezing methods did not cause any significant loss. In our experiment, thawing is found to be a more critical technique when compared to that of freezing. There were no clear quantifications or trends of pH and water content among different freezing and thawing techniques. The highest total color difference (${\Delta}E$) was observed in the NCF sample. For morphological observation, ABF gave the smallest ice crystal size, as well as minimum cell collapse. Loss of vitamin C, free sugar, and organic acid content was lower in the ABF and ST sample, when compared to other trials. In our study, we found that combination of ABF and ST could preserve the quality and nutritional aspects of frozen-thawed onions better than other methods.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.6
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• pp.422-429
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• 2013

It is generally known that the increase of the Earth surface temperature due to the global warming together with the land desertification by rapid urban development has caused severe climate and weather change. In desert or desertification land, it is observed that there are always severe flooding phenomena, even if desert sand has the high porosity, which could be believed as the favorable condition of rain water infiltration into ground water. The high runoff feature causes possibly another heavy rain by quick evaporation with the depletion of underground water due to the lack of infiltration. The basic physics of desert flooding is reasonably assumed due to the thermal buoyancy of the higher temperature of the soil temperature than that of the rain drop. Considering the importance of this topic associated with water resource management and climate disaster prevention, no systematic investigation has, however, been reported in literature. In this study, therefore, a laboratory scale experiment together with the effort of numerical calculation have been performed to evaluate quantitatively the basic hypothesis of run-off mechanism caused by the increase of soil temperature. To this end, first, of all, a series of experiment has been made repeatedly with the change of soil temperature with well-sorted coarse sand having porosity of 35% and particle diameter, 2.0 mm. In specific, in case 1, the ground surface temperature was kept at $15^{\circ}C$, while in case 2 that was high enough at $70^{\circ}C$. The temperature of $70^{\circ}C$ was tested as this try since the informal measured surface temperature of black sand in California's Coachella Valley up to at 191 deg. $^{\circ}F$ ($88^{\circ}C$). Based on the experimental study, it is observed that the amount of runoff at $70^{\circ}C$ was higher more than 5% compared to that at $15^{\circ}C$. Further, the relative amount of infiltration by the decrease of the surface temperature from 70 to $15^{\circ}C$ is about more than 30%. The result of numerical calculation performed was well agreed with the experimental data, that is, the increase of runoff in calculation as 4.6%. Doing this successfully, a basic but important research could be made in the near future for the more complex and advanced topic for this topic.

• Journal of Biomedical Engineering Research
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• v.31 no.4
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• pp.280-284
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• 2010

Approvals of medical device increase every year as industry of medical device grows. Therefore KFDA keeps trying to improve approval systems. However, the firms of medical device are in trouble due to regulation amendment, a firm of small size, exchange of the person in charge. The staffs of KFDA increase their work load because applicants of approval of medical device aren't used to writing of document. Therefore the firm of medical device in business have a long term. KFDA develops eight guidance document item by item for one-step evaluation and approval for Medical Devices because applicants of approval of medical device write documents easily. KFDA reviewer can carry on quick reviewing in use of this eight guidances. This guidance are improved on satisfaction of applicants of approval of medical device.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.1-15
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• 2020

This study was conducted to determine whether invasive muskrats settle in the natural ecosystem of Korea. The study also aimed to provide information on the selection of target areas, basic behavioral characteristics, and habitat use-related data, all of which are essential for effective management strategy establishment and site management. To this end, a trend in international muskrat management was identified to examine the management direction according to the settlement stage. We also secured the location of 72 domestic farmers and classified five regions in Gyeonggi-do, Chungcheongnam-do, Gyeongsangbuk-do, and Sejong Special Self-governing City into regions with high potential for natural leakage to raise the need for a quick survey. We determined that muskrats successfully settled in the natural ecosystem of Korea, based on the fact that we consistently identified a muskrat habitat at the same point for three years, from 2016 to 2018, the age of the captured population was estimated to be 1.2 years, and there had been no additional make-up factors near the habitat since 2012. The muskrats that settled in Korea showed a small home range of 0.0027 ㎢ (MCP 95%) and were estimated to show regular mobility before Spring and Autumn. Also, the areas where the muskrat habitat was observed had a high level of habitat environment disturbance and their ecological and food intake characteristics reflected that disturbance. Muskrat traces were high in hydrophyte vegetation, which can be used as a hideout in open waters and where the growth of both floating leaved plants and floating plants are prevalent. Since international invasive muskrats have already settled in the domestic ecosystem and there is concern about their proliferation in the future, the government must consider a preemptive response and scientific management.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.651-660
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• 2016

Due to recent population aging, the number of check-up for senior citizens has increased steadily. According to this trend, the market size of dental X-ray equipment and the number of approval and review for these devices have simultaneously increased. The technical document of medical device is required for approval and review for medical device, and medical device companies needs to have work comprehension and expertise, as the document needs to include the overall contents such as performances, test criteria, etc.. Yet, since most of domestic manufacturers or importers of medical devices are small businesses, it is difficult for them to recruit professional manpower for approval of medical devices, and submission of inaccurate technical documents has increased. These problems lead to delay of the approval process and to difficulties in quick entering into the market. Especially, the Ministry of Food and Drug safety (MFDS) standards of a dental extra-oral X-ray equipment, a dental intra-oral X-ray equipment, an arm-type computed tomography, and a portable X-ray system have been recently enacted or not. this guideline of dental X-ray equipment adjusting revised standards was developed to help relative companies and reviewers. For this study, first, the methods to write technical document have been reviewed with revised international and domestic regulations and system. Second, the domestic and foreign market status of each item has been surveyed and analyzed. Third, the contents of technical documents already approved by MFDS have been analyzed to select the correct example, test items, criteria, and methods. Finally, the guideline has been developed based on international and domestic regulation, through close review of a consultative body composed of academic, industrial, research institute and government experts.

• Korean Journal of Veterinary Research
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• v.14 no.1
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• pp.115-133
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• 1974

Although considerable research has been done on the changes associated with age in the blood picture of domestic and laboratory animals, little work has been made of the changes occurring at different age in the blood picture of goats. And a comprehensive survey of the bood picture of Korean native goats has not been made. The object of the present investigation was to suggest standards for the blood picture of Korean native goats at frequent intervals from birth to maturity. The goats were kept under average farming conditions in this country. Observations were made at the following ages: at birth; 2,4 and 7 days; 2, 3, 4, 5, 6, 7, 8 and 9 weeks; 2.5, 3,6 and 12 months. Blood samples were drawn from the jugular vein. It was taken between 8 and 9 a.m. except those for the at-birth period. Erythrocyte and leukocyte enumerations and, determinations of hemoglobin in blood and hematocrit value were made in the usual manner. Reticulocytes were enumerated per 1,000 erythrocytes in blood smears stained with briIliant cresyl blue and counterstained with Wright's stain. Erythrocytes counts declined from $8.7{\times}10^8/mm^3$ at birth to a low of 7.0 at 4 days of age. These values increased to 11.5 at 5 weeks and reached a maximum of 14.0 at 3 months of age; it then fell to 11.5 at 12 months of age. Concentrations of hemoglobin in blood and hematocrit values were not related to the changes of erythrocyte counts. The values at birth were higher than at any other period during the first year of life. These fell from highs of 12.3 g/100 ml and 38.0 ml/100 ml to lows of 9.2 and 29 at 4 weeks for concentration of hemoglobin in blood and hematocrit value, respectively. There was a common pattern for the hematocrit value and hemoglobin in blood which showed three phases-a fall during the first month, a rise to the third month, and a fall to the mature level at 12 months of age. Mean corpuscular volume and mean corpuscular hemoglobin showed a common pattern. The values were $44.2{\mu}m^3$ and 14.2 pg at birth and fell, at first slowly and then rapidly, to reach adult levels of 24.1 and 7.9 at 6 weeks of age for mean corpuscular volume and mean corpuscular hemoglobin, respectively. Mean corpuscular hemoglobin concentration was little affected by age. Reticulocyte was observed from birth to 4 weeks of age. Percentage of reticulocyte decreased from 0.85% at birth to 0.06% at 4 weeks of age. Total leucocyte counts increased from $5.64{\times}10^3/mm^3$ at birth to a maximum of 13.4 at 3 months; it then fell to 11.5 at 12 months of age. In differential counts myelocyte, juvenile and band form decreased with advancing age. No myelocyte and juvenile were seen after the age of 7 and 9 weeks, respectively, and band forms were rare after the age of 3 months. Percentage of mature neutrophil showed a quick decline from 52.5% at birth to reach a minimum level (34.5%) at 3 months of age; it then rose to 38% at 12 months of age. Percentage of lymphocyte increased from 39.2% at birth to maximum of 59% at 3 month of age; it then fell to 54.9% at 12 months of age. Percentage of monocyte was not affected with advance of age. Percentage of eosinophil and basophil were increased with advance of age to reach a maximum at 2 to 3 month of age. It then fell to adult level at 12 month of age.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.07b
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• pp.67-88
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• 2003

The consumption of poultry meat (chicken and turkey) grew the most during the past few decades due to several contributing factors such as low price. product research and development. favorable meat characteristics, responsive to consumer needs, vertical integration and industry consolidation, new processing equipments and technology, and aggressive marketing. The major processing technologies developed and used in chicken processing include forming/restructuring, tumbling, curing, smoking, massaging, injection, marination, emulsifying, breading, battering, shredding, dicing, and individual quick freezing. These processing technologies were applied to various parts of chicken including whole carcass. Product developments using breast, thigh, and mechanically separated chicken meat greatly increased the utilization of poultry meat. Chicken breast became the symbol of healthy food, which made chicken meat as the most frequent menu items in restaurants. However, the use of and product development for dark meat, which includes thigh, drum, and chicken wings were rather limited due to comparatively high fat content in dark meat. Majority of chicken are currently sold as further processed ready-to-cook or ready-to-eat forms. Major quality issues in chicken meat include pink color problems in uncured cooked breast, lipid oxidation and off-flavor, tenderness PSE breast, and food safety. Research and development to ensure the safety and quality of raw and cooked chicken meat using new processing technologies will be the major issues in the future as they are now. Especially, the application of irradiation in raw and cooked chicken meat products will be increased dramatically within next 5 years. The market share of ready-to-eat cooked meat products will be increased. More portion controlled finished products, dark meat products, and organic and ethnic products with various packaging approaches will also be introduced.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.5
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• pp.316-325
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• 2001

To develope a technique for efficiently managing fertilizer for cucumber, a quick test method to quantify nitrate content in soil solution and leaf petiole juice using a simple instrument was investigated. Among the nitrate analyzing instruments such as compact ion meter, nitrate ion meter, and test strip with reflectometer, the paper test-strip used in conjunction with a hand-held reflectometer was most closely correlated with ion chromatography method in nitrate content, and then it would be suggested with a tool that a farmer can use rapidly, conveniently and accurately for nitrate analysis in a field. Nitrate content in soil solution collected by porous cup was very variable on the lapsed time after drip irrigation and the sampling positions such as soil depth and the distance from dripper. As a result, a significant correlation between nitrate contents of soil solutions and 2M KCl soil extract was not found. However, nitrate content in soil solution extracted with a volume basis (soil:water=1:2) showed the highly significant correlation with that in 2M KCl extract. Nitrate contents of cucumber leaf petiole juices was greatly different between upper and lower leaves. Eleven to sixteen positioned-leaf would be a proper sampling position to determine nitrate content in leaf petiole for evaluating nutrient state by plant tissue analysis. From the secondary regression equations between nitrate contents of soil and petiole juice and the yield of cucumber, nitrate levels for real time diagnosis were estimated as $400mg\;l^{-1}$ soil solution by porous cup. $300mg\;l^{-1}$ in a soil volume extraction, and $1400mg\;l^{-1}$ in petiole juice from spring to summer season. In addition, the maximum yield of cucumber fruit in pot test was obtained in nitrate $1500mg\;l^{-1}$ level of petiole juice, which was similar to nitrate $1400mg\;l^{-1}$ in greenhouse trial.

• Korea Journal of Hospital Management
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• v.9 no.2
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• pp.46-75
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• 2004

This research anticipated on acknowledging the inpatients factors in choosing which hospital for the geriatric hospital and general hospital they would prefer to go to the analization of different factors in patients satisfaction, and the relation between satisfactory standards and the patients intentions on recommendation or re-visiting the hospital. The statistical data was based upon the 359 question and answer papers that were done by inpatients that were hospitalized in two geriatric hospitals and two general hospitals, and the methods used for analyzing were frequency, t-test, factor analysis, and hierarchical multiple regression. The results are as follows. 1. The factors on choosing hospitals between geriatric hospital and general hospitals were different. The priority for the geriatrics was kindness, and then considerate nursing, and the reliance of treatment. The patients of general hospitals looked first for reliance of treatment, reputation and history of the hospital, and the kindness of the staff. The kindness of the staff, good nursing, and easy procedures were the primary factors of choosing geriatric hospital. 2. The four primary factors in choosing which hospital patients would go to were the predominance of the facilities, kindness and convenience, the reliance and proximity of medical treatment, and recommendation. The patients in the geriatric hospital first looked for kindness and convenience, second the reliance and proximity of medical treatment, third predominance of facilities, and last recommendation. The general hospitals main priority was the reliance and proximity of medical care, second predominance of facilities, kindness and hospitality, and last recommendation. 3. The satisfaction rate was higher in the geriatric hospital compared to general hospitals, but the satisfactory of factors were very similar. Patients in the geriatric hospital were pleased with the hospital staffs kindness, quick nursing and the improvement of inconvenient matters, and clear diagnosis of the doctors. The general hospital patients were satisfied with the hospital staffs clear explanation and accurate diagnosis 4. The analysis in the satisfactory factors turned out to be the environment of the hospital, kindness of the staff, and convenience. Both the patients of the geriatric hospital and general hospitals were very pleased with the kindness of the hospital staff. Ranking second and third was convenience and service for the geriatric hospital, and environment of the hospital and convenience for the general hospital. 5. According to a rank of multiple recurrent analysis of the patients satisfaction and the intention of re-visiting in addition to intention of solicitation, in the case of a geriatric hospital, when the intention of re-visiting is the dependent variable, the first stage shows that the less insurance the patient has, the higher was the intention of re-visiting. In the second stage, the more satisfied the patient is of the staffs kindness, the higher was the intention of re-visiting. Further more, when the intention of solicitation is the dependent variable, the first stage shows that not all the independent variables were significant, but the second stage shows that the more satisfied the patient is of the staffs kindness and the hospital along with the medical treatment expenses, the higher was the intention of solicitation. 6. In the first stage of a rank of multiple recurrent analysis of the satisfaction of the general hospital and the intention of re-visiting, not all the variables were significant, but in the second stage, all the satisfaction by factors were significant. Moreover, when the intention of solicitation was the dependent variable, the first stage shows not all the variables were significant, but in the second stage, all the satisfaction by factors were significant. That is to say, in the case of a general hospital, the satisfaction of the hospital and the medical treatment expenses were high, and the more satisfied the patient is of the hospitals environment and the staffs kindness, the intention of re-visiting and the intention of solicitation was higher.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.217-225
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• 2002

When we use the flowable resin on the primary molars for quick handling, one of the most important property is the wear resistance. This study was performed to compare the wear resistance characteristics of four flowable composite resins [Arabesk flow (group 1), Tetric flow (group 2), Aeliteflow (group 3), Filtek flow (group 4)] to that of one control composite resin [Z100 (group 5)]. Specimen discs(n=10), 10mm wide and 2mm thick, were stored in distilled water at $37^{\circ}C$ for 7 days prior to testing. The specimens were subjected to 50,000 strokes at 2 Hz on the MTS system. During the test, the following parameters were maintained: the lateral excursion at 0.4mm, occlusal force at 2-100N with a force profile in the form of a half sine wave. The measurements of volume loss, depth of wear, and Vicker's hardness number of composite resins, and SEM observations of the polished and abraded surfaces were established. One-way ANOVA and Scheffe's multiple comparison test were employed to detect statistically significant differences among the flowable composite resin groups and the control composite group at P<.05. The following results were obtained: 1. Group 3 showed the least volume loss, while group 4 showed the greatest. The mean volume loss increased in the following order: group 3