• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.12
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• pp.819-828
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• 2022

Sensitivity of aircraft sizing depending on battery performance was studied for a generic quad tilt rotor type electric vertical takeoff and landing vehicle. The mission requirements proposed by Uber Elevate and NASA were used for initial sizing, and the calculated gross weight is ranged between 5,000lb and 11,000lb for battery specific energy range of 200-400Wh/kg in pack level and continuous discharge rate range of 4-5C. For the assumed gross weight of 7,000lb, the required battery performance was calculated with two different criteria: available power and energy, and the effects of battery specific energy and discharge rate are analyzed. The maximum discharge rate is also recommended considering failure cases such as one battery pack inoperative and one prop rotor inoperative.

• Journal of the Society of Disaster Information
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• v.16 no.2
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• pp.237-247
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• 2020

Purpose: This study aims to draw the problems and improvements of NFSC 103 sprinkler head discharge obstruction prevention standard to increase the fire extinguishing performance of sprinkler system in order to contribute to the protection of people's lives and property in the event of a fire. Method: NFSC 103 was compared to NFPA 13 which is the latest 2019 version in U.S in terms of sprinkler head discharge obstruction prevention. Results: This study found that NFSC 103 doesn't define even the basic concept of sprinkler discharge obstruction. And NFSC 103 doesn't have detailed standard for side wall sprinkler head discharge obstruction prevention as well as the "height" criteria of the "three times" separation rule. Conclusion: NFSC 103 needs a lot of supplements and improvements such as the addition of definition for water discharge obstructions, the adoption of sidewall sprinkler heads standard for preventing water discharge obstructions and the additional establishment of the "three times rule" considering the "height" of obstacles to promote the advance of fire safety standard equal or above fire fighting advanced country and increase the reliability for the suppression performance of sprinkler system.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.369-377
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• 2018

EAP, which is operated on the frame of Risk Alarm 4-stage of National Risk Management Guideline, is a critical method in order to promptly respond to disasters. Korea Flood Control Office issues major and moderate flood alarm at each river station by respectively 50% and 70% of design flood discharge in terms of watermark or sea level, however, the criteria deciding major and moderate floods are vague for field managers to control the disaster situations. On the other hand, Japan and USA use river water level as a main criterion in order to classify the stage of flood disaster, which is higher design flood level than Korea. Thus, the authors analyzed domestic and oversea EAP guidelines and suggested improved criteria showing easy display method and raising the criteria of flood level for reflecting more effective action plans through testing a simulation training on the test-bed.

• KCID journal
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• v.19 no.1
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• pp.64-76
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• 2012

Recently, it has been increased disaster of crops and agricultural facilities with climate change such as regional storm, typhoon. However agricultural facilities have unsafe design criteria of improving drainage corresponding to this change. This study has analyzed the impact that inundation area and magnitude of drainage-facility is decided based on fixed- and unfixed-duration precipitation by applying revised design criteria of drainage for climate change. The result was shown that 1-day and 2-days rainfall for 20-years return period has increased about 11.4%, 4.4% respectively by changing fixed- to unfixed duration. And the increase rate of design flood was 15.0%. The result was also shown that Inundation area was enlarged by 6.6% as well as increased inundation duration under same basic condition in designed rainfall between fixed- and unfixed-duration. According to the analysis, it is necessary for pump capacity in unfixed-duration to be increased by 70% for same effect with fixed-duration. Therefore, when computing method of probability precipitation is changed from fixed one to unfixed-duration by applying revised design criteria, there seems to be improving effect in drainage design. Because 1440-minutes rainfall for 20-years return period with unfixed-duration is more effective than 1-day rainfall for 30-years return period with fixed-duration. By applying unfixed-duration rainfall, capacity of drainage facilities need to be expanded to achieve the same effects (Inundation depth & duration) with fixed-duration rainfall. Further study is required for considering each condition of climate, topography and drainage by applying revised design criteria.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.6
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• pp.5-18
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• 1999

This study was attempt to encourage for developing on rehabilitation delivery system and programs as a substitute service instead of hospitalization for accident patients at work, such as hospital based home health care nursing service. It needs vary substitutes service of hospitalization to curtail the length of stay for inpatients who were hospitalized with workers compensation insurance. It focused on developing an estimation of early discharge day of accident inpatients based on a detail statement of treatment for 115 inpatients who were hospitalized at General Hospital in 1997. This study has four specific purpose as follows. First, to find out the status of health service utilization. Second, to estimate the early discharge days and income increasing effect based on the early discharge for those patients. Third, to identify the factors to affect total medical expenditure and the length of stay for those inpatients. Forth, to figure out the need of utilizing home health care nursing service for accident patients. In order to analyze of the length of stay and medical expenditure for inpatients who were hospitalized due to the accident, the authors conducted with micro-analysis and macroanalysis from medical records and medical expenditure records. Micro-analysis was done by nominal group discussion of 4 expertise with the critical criteria. such as a decrease in the amount of treatment after surgery, treatments, tests, drugs and changes in the tests consistency, drug methods, vital signs, start of ROM exercise, doctor's order, patient's outside visiting ability, stable conditions. In addition to identify affected variables for medical expenditure. the length of stay and income effect due to early discharge day, the data was analyzed with multiple regression analysis and linear regression analysis model by SPSS-PC for windows and Excell program. Results of this study as follows. First, the mean length of stay was 37.1 days, whereas the mean length of stay due to early discharge was 28.2 days at the hospital. The estimation of early discharge days were shown that depends on the length of stay. The longer length of stay, the longer length of early discharge days, such as under 7 days length of stay patients was to estimated the mean length of stay was 4.9 days and early discharge days was 4.6. whereas the mean length of stay was 122.6 days and early discharge days was 92.0 respectively. The mean medical expenditure per day were found to be 133.409 Won. whereas the mean medical expenditure per day was shown negative linear trends according to the length of stay at the hospital. The estimation results of the income effect due to 11 early discharge days per bed was around 2,150,000 won. However, it means not the real benefits from early discharge, but the income increasing amount without considering medical prime cost in general hospital. Therefore, it needs further analysis on the cost containments and benefits under the considering as well turn over rates per bed as the medical prime costs. The length of stay was most significant and the sign was positive to the total medical expenditure, as expected. Surgery and patient's residential area also an important variable in explaining medical expenditure. The level of complications was most significant variable in explaining the length of stay. The level of the needs on horne health care nursing service which can be used for early discharge accident patients were shown very high. The needs distribution varied from 65.5% of patients and 88.9% of caregivers, to 96.4% of doctors, and 99.1% of nurses. In addition horne health nurse responded that they can be managed the accident inpatients from early discharge. From these research findings. the following suggestions has been drawn it needs to develop strategies on rehabilitation delivery system in order to focused on consumer's side which is planned for 21 century health policy in Korea. Vary intermediate facilities and horne health care would have been developed in the community based for comprehensive rehabilitation services as a substitutes of hospitalization for shortening the length of stay of hospitalizations. In hospital based horne health care nursing service, it's available immediately to utilize for the patients who wanted rehabilitation services as a substitutes of hospitalization under the cooperations with workers compensation insurance company.

• Journal of Navigation and Port Research
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• v.30 no.9
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• pp.755-762
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• 2006

When we consider to develop a new harbor, the most important factor, we think, is the lowest water depth of waterway and approaching channel for safe navigation of vessel. The existing harbors have been being dredged to meet the international trend of jumbo sized vessels by adopting the new design criteria. As the dredged materials over the expected at the design level were common and there are still lack of land based reclamation area, we have no choice to discharge the dredged materials in open sea area In this study, we analysed the behavior of discharged materials at the dumping area of offshore, which were collected from the dredging work at the waterway in Busan New Port. We measured the tidal currents and analyzed the waters of dumping site after the dumping work. These were used to evaluate the numerical models. Suspended Solids(SS) were introduced to the diffusion model. Because of the characteristic of the dumping site, the speed of initial diffusion and settle down of the discharged materials was so fast. Therefore, we believe that the dumped materials do not cause a significant impact to the marine environment.

• The Journal of Internal Korean Medicine
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• v.30 no.3
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• pp.534-549
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• 2009

Objectives : To study trends in complementary medical therapy for the allergic rhinitis. This study analyzed research on allergic rhinitis in PubMed. Methods : We searched PubMed related to complementary medical therapy for allergic rhinitis. We analyzed 25 research papers and examined published journals, years countries, and their methods, objectives, results, interventions, participants, periods and instruments of assessment. Results : The method of studies was mostly randomized, double-blind, placebo-controlled trial. There were research papers concerning treatment and prevention with herbal medicine, acupuncture, diet, etc. There were more positive results compared to negative results for treatment and prevention. Most studies were carried out during the winter/spring period. The median for number of participants was 90.54 persons. Diagnostic criteria for enrolment were nasal symptoms, allergic skin test, serum, nasal discharge allergen specific IgE eosinophil, etc. Assessment for outcomes were nasal symptoms, serum, nasal discharge allergen specific IgE eosinophil and Quality of Life Questionnaire. Conclusions : It is necessary to study effects of acupuncture and herb medicines for allergic rhinitis and more in-depth research about trends in complementary medical therapy for allergic rhinitis.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.spc
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• pp.37-50
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• 2020

In this paper, an overview of the scoping calculation results is provided with respect to criticality and radiation shielding of two KBS-3V type PWR SNF disposal systems and one NWMO-type CANDU SNF disposal system of the improved KAERI reference disposal system for SNFs (KRS⁺). The results confirmed that the calculated effective multiplication factors (k_eff) of each disposal system comply with the design criteria (< 0.95). Based on a sensitivity study, the bounding conditions for criticality assumed a flooded container, actinide-only fuel composition, and a decay time of tens of thousands of years. The necessity of mixed loading for some PWR SNFs with high enrichment and low discharge burnup was identified from the evaluated preliminary possible loading area. Furthermore, the absorbed dose rate in the bentonite region was confirmed to be considerably lower than the design criterion (< 1 Gy·hr^-1). Entire PWR SNFs with various enrichment and discharge burnup can be deposited in the KRS⁺ system without any shielding issues. The container thickness applied to the current KRS⁺ design was clarified as sufficient considering the minimum thickness of the container to satisfy the shielding criterion. In conclusion, the current KRS⁺ design is suitable in terms of nuclear criticality and radiation shielding.

• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.37-52
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• 1992

Since the first sewage treatment plant was constructed in 1976, the sewerage systems of Korea have been rapidly expanded. As of the end of 1991, 22 sewage treatment plants with total capacity of 5.4 million tons/day are in operation which is equivalent of 3395 total daily sewage generation. Total extension of sewer 39.534 km in 1990 which is 55% of the target extension for the year 2001. However, the most sewage treatment plants employ activated sludge process which may not be suitable for medium and/or small scale plants. The poor existing sewer systems do not effectively collect and transport sewage to adversely affect the function of sewage treatment plant. To select the appropriate treatment system, the cities are classified into 3 categories such as large and medium size inland cities, small size cities and coastal cities. Considering the criteria suggested during this study, appropriate treatment processes were selected for each category. Conventional activated sludge process and step aeration process were found to be the most appropriate for big inland cities while biological nutrient removal processes should be considered for the cities discharge the effluent to lakes or reservoirs. RBC or Oxidation Ditch process might be appropriate for the medium size cities while several processes which do not require skilled operation and maintenance were suggested for the small cities. Ocean discharge after primary treatment can be considered for some east coast cities, Appropriate methodology to rehabilitate the existing sewers and strategy to convert combined sewer system to separate sewer system were proposed. This paper also include the appropriate management system for industrial wastewater, sludge and nightsoil.

• Clinical and Experimental Pediatrics
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• v.50 no.4
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• pp.323-327
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• 2007

Although most clinicians now agree that sinusitis can afflict children of all ages, appropriate diagnosis remain controversial. Sinusitis is one of the most challenging diagnoses for a clinician, because there is a lack of validated diagnostic criteria for acute rhinosinusitis. Symptoms generally include nasal congestion, purulent nasal discharge, and cough .The physical examination is often unsuccessful in confirming the diagnosis. If purulent discharge is seen oozing from the middle meatus, the diagnosis of acute rhinosinusitis is almost certain. Purulent drainage may also be seen in the posterior pharynx and accompanied by halitosis. Absence of light by transillumination may indicate acute rhinosinusitis. Imaging studies are not necessary to confirm the diagnosis of sinusitis in children younger than 6 years and should be used sparingly in children older than 6 years. Sinus radiographs still have several advantages over CT scanning including the relatively low cost and the ability to obtain films without the use of sedation in younger children. Positive findings of sinusitis on plain film include air-fluid levels, complete opacification, or mucosal thickening greater then 4 mm. The CT scan however, is significantly more sensitive then plain films in detecting these abnormalities. Although recovery of bacteria from a sinus aspiration is considered reference standard for diagnosis in pediatric rhinosinusitis, its routine used by pediatricians is not practical and therefore is not recommended.