• Journal of Surface Science and Engineering
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• v.56 no.3
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• pp.192-200
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• 2023

Graphene, a two-dimensional material, has shown great potential in a variety of applications including microelectronics, optoelectronics, and graphene-based batteries due to its excellent electronic conductivity. However, the production of large-area, high-quality graphene remains a challenge. In this study, we investigated graphene growth on electrolytic copper foil using thermochemical vapor deposition (TCVD) to achieve a similar level of quality to the cold-rolled copper substrate at a lower cost. The combined effects of pre-annealing time, graphenized temperature, and partial pressure of hydrogen on graphene coverage and domain size were analyzed and correlated with the roughness and crystallographic texture of the copper substrate. Our results show that controlling the crystallographic texture of copper substrates through annealing is an effective way to improve graphene growth properties, which will potentially lead to more efficient and cost-effective graphene production. At a hydrogen partial pressure that is disadvantageous in graphene growth, electrolytic copper had an average size of 8.039 ㎛², whereas rolled copper had a size of 19.092 ㎛², which was a large difference of 42.1% compared to rolled copper. However, at the proper hydrogen partial pressure, electrolytic copper had an average size of 30.279 ㎛² and rolled copper had a size of 32.378 ㎛², showing a much smaller difference of 93.5% than before. This observation suggests this potentially leads the way for more efficient and cost-effective graphene production.

• Journal of the Korea Knowledge Information Technology Society
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• v.12 no.1
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• pp.69-78
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• 2017

KOIN (Korean medicine 人, http://www.koin.re.kr) is a Korean medicine knowledge portal developed for users who are interested in Korean medicine to share relevant information. The purpose of the present study is to seek methods for advancing the quality of the contents and services of KOIN to secure future users of the portal services before fully initiating the KOIN service. The crowd testing method was applied to test the functionality and usability of the current KOIN service, and domestic and international websites providing similar services were investigated and analyzed. About 150 errors were found in this functional testing procedure, but the identified functional problems were all corrected. An average score of 3.33 was calculated in the usability test, in which the reliability and the playfulness showed the highest and lowest score, respectively. We in this paper surveyed the 15 relevant websites with respect to KOIN in the traditional medicine and the modern medicine fields. The strengths and weaknesses of similar websites were analyzed to improve the KOIN services. In particular, it is shown that the evidence-based Korean medicine knowledge is KOIN's biggest strength. Users' needs and demand for the KOIN services will be continuously gathered to provide the Korean medicine knowledge services that the users require.

• Journal of the Korean earth science society
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• v.40 no.6
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• pp.549-560
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• 2019

The effects of the coal-fired power plant emissions, as the biggest point source of air pollutants, on spatiotemporal surface air pollution over the remote area are investigated in this study, based on a set of date selection and statistical technique to consider meteorological and geographical effects in the emission-concentration (source-receptor) relationship. We here proposed the sophisticated technique of data processing to separate and quantify the effects. The data technique comprises a set of data selection and statistical analysis procedure that include data selection criteria depending on meteorological conditions and statistical methods such as Kolmogorov-Zurbenko filter (K-Z filter) and empirical orthogonal function (EOF) analysis. The data selection procedure is important for filtering measurement data to consider the meteorological and geographical effects on the emission-concentration relationship. Together with meteorological data from the new high resolution ECMWF reanalysis 5 (ERA5) and the Korea Meteorological Administration automated surface observing system, air pollutant emission data from the telemonitoring system (TMS) of Dangjin and Taean power plants as well as spatio-temporal air pollutant concentrations from the air quality monitoring system are used for 4 years period of 2014-2017. Since all the data used in this study have the temporal resolution of 1 hour, the first EOF mode of spatio-temporal changes in air pollutant concentrations over the Seoul metropolitan area (SMA) due to power plant emission have been analyzed to explain over 97% of total variability under favorable meteorological conditions. It is concluded that SO₂, NO₂, and PM₁₀ concentrations over the SMA would be decreased by 0.468, 1.050 ppb, and 2.045 ㎍ m^-3 respectively if SO₂, NO₂, and TSP emissions from Dangjin power plant were reduced by 10%. In the same way, the 10% emission reduction in Taean power plant emissions would cause SO₂, NO₂, and PM₁₀ decreased by 0.284, 0.842 ppb, and 1.230 ㎍ m^-3 over the SMA respectively. Emissions from Dangjin power plant affect air pollution over the SMA in higher amount, but with lower R value, than those of Taean under the same meteorological condition.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.5
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• pp.33-47
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• 2011

One of the most fundamental jobs of contemporary government is to look into various ways of providing its citizens with the best service work. This study aims to establish a procedure through which to consign the management of city parks to private companies, thus inviting participation and satisfaction on the part of citizens. In particular, this procedure includes creating a system of selecting private managing companies, for instance, specifying standards of selection and assembling selection committees. The results of this study can be summarized as follows. First, city parks can be managed better by private companies than by local governments in terms of cost cuts, personnel training, business efficiency, and know-how accumulation. The legal background for this is found in central and local legal articles. Second, it is recommended that the selection committee be composed of 6 to 9 members, both insiders and outsiders. In addition to selecting private managing companies for contracting-out, the committee should under take the role of consulting on how to perform and revise selecting standards, so that they can continue to improve these procedures. Third, the decision on private management should be noticed in advance and be made based on standards considering each local government's condition. These standards should consider the aspects of the public good, cost saving, quality of service, managing supervision, and citizen participation. The committee's assessment takes into account both the quality and the quantity of the standards. Fourth, the contracting-out for city park management should follow the order of: announcing consignment and receiving applicants, organizing selection committees and assessing applications, selecting and contracting, midterm evaluation, and re-announcement and re-consignment. To run city parks through the contracting-out is expected to increase the number of park visitors. Additionally, private consignment will involve a participation of diverse citizenship, thus playing an important role in city parks' building of a green-culture community.

• Korea Journal of Hospital Management
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• v.8 no.1
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• pp.112-134
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• 2003

The purpose of this study is to analyze the consumer's expectation before the health care service and the consumer's satisfaction after it. The participants of the study are inpatients in a general hospital located in Seoul. The resources were collected from the self-administration questionnaire survey run parallel with face to face interview. In order to measure the degree of the consumer's expectation, 349 samples were collected from the first questionnaire survey on the date of admission to the hospital. The second questionnaire survey was carried out on the date of discharge to the hospital with the participants responding to the first questionnaire survey. There are 154 samples collected from this survey. The results from the analysis of these resources are as follow. First, the survey shows that one of the highest consumers' expectations was about the generosity, kindliness and sincerity from the staff at the hospital, specially from doctors. Second, according to the analysis of the factors affecting the expectations of the consumers, with regard to path of admission to a hospital relating to patient's features, outpatient who gets into a hospital expected good medical care much more than the other patients. In regard of doctor's features, patients usually and highly expect good medical care from doctors who have good carrier and much experience. Third, according to the second questionnaire survey, what patients are satisfied most with is about the generosity and sincerity from staff at a hospital, especially from doctors and their gem attitudes. The results from survey show that the differences among the degree of consumers' satisfaction are very variable, depending on surrounding environments and facilities. The only fact that expectation didn't meet with satisfaction appeared to the case about technology and skill of medical care and the case about updated medical skills and equipments. Fourth, comparing the degree of expectation with the degree of satisfaction of consumers, correlative analysis was concerned significantly and specifically about the part of overall cleanliness relating to facilities and surrounding environments, the items about medical examination and test plan procedure relating to skill of medical care, professional specialties and convenience for procedure, and the items about satisfying explanations and concern about patients from doctors relating to staff's generosity and sincerity. Fifth, the analysis of the factors affecting the degree of how much patients are satisfied with shows that relating to sociodemographical features, patients are not satisfied with the case when the time and process of medical treatment are getting longer. It is surveyed that consumer were satisfied with the motivation to visit a hospital and the insurance type in patient's feature and so were the medical department and the factor of the degree of the expectation in disease's feature. Sixth, according to analysis based on the survey, patients would join again a hospital when they get satisfaction from the medical care and also they want to come again regarding to doctor's capability. For example, when doctors are old, have a good carrier and much experience, patients would come again. As seen from the above, consumers are usually satisfied with the medical treatment more than that they expected before. They would intend to use again when they get satisfaction from the medical care provided at a hospital. Patients and consumers highly expect good attitude as well as capacity from medical doctors and they are also generally satisfied with those things. Therefore, in order to increase the degree of consumer's satisfaction and their intention to come again, the hospital staff would have to commit themselves to achieve high quality service continuously and would have to make an effort to offer the finest quality service.

• Progress in Medical Physics
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• v.24 no.2
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• pp.92-98
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• 2013

The experimental verification of treatment planning on the treatment spot is the ultimate method to assure quality of radiotherapy, so in-vivo skin dose measurement is the essential procedure to confirm treatment dose. In this study, glass rod dosimeter (GRD), which is a kind of photo-luminescent based dosimeters, was studied to produce a guideline to use GRDs in vivo dosimetry for quality assurance of radiotherapy. The pre-processing procedure is essential to use GRDs. This is a heating operation for stabilization. Two kinds of pre-processing methods are recommended by manufacturer: a heating method (70 degree, 30 minutes) and a waiting method (room temperature, 24 hours). We equally irradiated 1.0 Gy to 20 GRD elements, and then different preprocessing were performed to 10 GRDs each. In heating method, reading deviation of GRDs at same time were relatively high, but the deviation was very low as time went on. In waiting method, the deviation among GRDs was low, but the deviation was relatively high as time went on. The meaningful difference was found between mean reading values of two pre-processing methods. Both methods present mean dose deviation under 5%, but the relatively high effect by reading time was observed in waiting method. Finally, GRD is best to perform in-vivo dosimetry in the viewpoint of accuracy and efficiency, and the understanding of how pre-processing affect the accuracy is asked to perform most accurate in-vivo dosimetry. The further study is asked to acquire more stable accuracy in spite of different irradiation conditions for GRD usage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.6158-6167
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• 2014

The aim of this study was to perform comparative analysis of the duties of 7 new roles of HIMs in Malaysian and Korean hospitals of a similar scale. A Malaysian general hospital with a scale of 272 hospital beds was chosen. The researcher visited a Malaysian hospital in person and interviewed the staff in charge over a 2 week period from July 22nd 2013 to August 2nd 2013. For domestic hospitals, 13 general hospitals with 270 hospital beds, similar to the Malaysian general hospital, were chosen. Phone interviews with the department recorded the duty recording work. Regarding 7 new roles of Health Information Manager (HIM), although the role as a Health information manager and Security Officer in Malaysian general hospital was not defined, 30.8% performed their role in Korean general hospitals. The classification of disease & procedure within the role of Clinical data specialist was performed by both countries, and while the tumor registry was done in a Malaysian general hospital, only 15.4% of Korean general hospitals were operating. The statistics of the discharged patients were not measured in the Malaysian general hospital but 76.9% of Korean general hospitals recorded these statistics. Although 22.1% of Korean general hospitals operated registration work of special disease, Malaysian general hospital not only had a total legal contagious disease registration, but also took charge of information registration of hospital births and deceased ones. Other than these, the Patient Information Coordinator, Data Quality Manager, Document and Repository Manager, Research and Decision Support Analyst roles were not done by either country. The new role of HIM is operated in a low percentage in Korean middle and small hospitals. Therefore, to clearly establish the role of HIM in Korea, and have middle and small hospitals to operate such a role, it is essential for the related association to give continuous education and provide support to clarify the role within the hospital working environment. It is desirable to benchmark Malaysian general hospital's registration work on special diseases and others, and expand the work to improve overall.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.3
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• pp.159-166
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• 2007

Objective: To investigate whether semen parameters in infertile couples who undergone intrauterine insemination (IUI) change in the subsequent IUI cycle and the subsequent in vitro fertilization (IVF) cycle. Methods: Fifty-three infertile couples who had failed to become pregnant after the first IUI cycle with computer-assisted semen analysis (CASA) were included. After the first IUI, thirty-eight couples underwent the second IUI (Group 1), and fifteen underwent IVF-ET procedure (Group 2). All semen parameters including semen volume, concentration, motility and total motile sperm count were analyzed in the second IUI or IVF-ET procedure for comparison with the result of first IUI. Results: There were no significant differences in husband age, interval between the first and second procedure and cause of infertility. In Group 1, only sperm motility at the time of the latter IUI was significantly decreased when compared to the former IUI irrespective of the first semen parameters. In Group 2, sperm concentration, motility and total motile sperm count at the time of subsequent IVF were lower than the former IUI. By sub-analyses of Group 2, in the group of optimal semen parameter at IUI cycle, sperm concentration and total motile sperm count at the time of subsequent IVF were lower than the former IUI, while in the group of suboptimal semen parameter at IUI cycle, only sperm motility at the time of subsequent IVF were lower than the former IUI. Conclusion: The semen parameters in couples converted to IVF cycle were more adversely affected than those remained in IUI cycle. Further study on psychological stress should be necessary to explain the reason.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.446-455
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• 2015

Based on comparative studies on standards and grading procedures of machine graded lumber in Korea and other countries, this study proposed a procedure of determining the grade classification and design strengths of domestic machine graded lumber. Differences between machine stress rated lumber and E-rated laminations were detailed in order to clarify the need for the procedure improvement. To this improvement the use of average MOE requirement for grading was introduced instead of the fixed minimum MOE requirement which is currently used in the Korean standards. It was found that the fixed minimum MOE requirement method was easier for an inspector to grade but, less efficient as a strength predictor than the average MOE requirement method. The advantage of average MOE requirement method is statistically MOR-MOE regression-based MOR prediction and highly efficient in quality control though it requires a computer-aided operation system in an initial setup. A major weakness of the current Korean grading system was found that different strength characteristics depending on wood species were not reflected on the grade classification and the tabulated allowable design stress. The proposed procedures were developed taking advantages of respective merits of both methods and based on MOR-MOE regression analysis. Through this procedure, the grades of machine stress rated lumber should be revised to become interchangeable with E-rated lamination, which would be beneficial to the cost competitiveness of domestic machine graded lumber and glued laminated timber industry.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.86-91
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• 2009

Purpose: The whole body scan in Nuclear Medicine is a widely accepted examination and procedure. Especially, it is mainly used in bone, I-131, MIBI, and HMPAO WBC scans. The diverse uses of the whole body scan range from the HMPAO WBC scan with a speed of 13cm/min, to a whole body bone scan using the Onco. Flash technique with a speed of 30cm/min. The accuracy of table movement has a strong correlation with the image quality, and inaccuracy of speed could negatively affect the image quality. The purpose of this study is to evaluate the accuracy of the table movement while considering the influence of the age of the equipment and the variability in the weight of the patients. Material and Methods: The study was conducted using two of Seoul Asan Medical Center's SIEMENS gamma cameras which are commonly used in our whole body study. The first one is the oldest gamma camera, an ECAM plus (installed in 2000), and the last is brand new one, a SYMBIA T2 (installed in 2008). Three trials were conducted with the tables moving at a different speed each time; 10, 15 and 30 cm/min. The tables' speeds were measured by checking how long it took for the table to move 10cm, and this was repeated every 10cm until the table reached 100 cm. With an average body weight of the patients of about 60~70 kg, the table speed was measured with weights of 0 kg, 66 kg and 110 kg placed on the table, then compared among conditions. Results: The coefficient of variance (CV) of the ECAM plus showed 1.23, 1.42, 2.02 respectively when the table movement speeds were set at 10, 15, and 30 centimeters per minute. Under the same conditions, the SYMBIA T2 showed 1.23, 1.83 and 2.28 respectively. As table movement speed more, the variance of CV as the speed increases. When the patient body weight was set to 0, 66 and 110kg, the CV values of both cameras showed 0.96, 1.45, 2.08 (0 Kg), 1.32, 1.72, 2.27 (66 Kg) and 1.37, 1.73, 2.14 (110 Kg). There was no significant difference (p>0.05) in 95 percent of confidence intervals and measured CV values were acceptable. However, the CV value of the SYMBIA T2 was relatively larger than the ECAM plus. Conclusion: The scan speed of the whole body scan is predetermined based on which examination is being performed. It is possible for the accuracy of the speed to be affected, such as the age of the equipment, the state of the bearings or the weight of a patient. These factors can have a negative impact on the diagnostic consistency and the image quality. Therefore, periodic quality control should be needed on the gamma cameras currently being used, focusing on the table movement speed in order to maintain accuracy and reproducibility.