• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.2
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• pp.1-8
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• 2010

The purpose of the study was to evaluate the influence of landscaping pavements on WBGT(Wet-Bulb Globe Temperature) of outdoor spaces that lack ventilation and shade at summer midday. The relative humidity(RH), dry-bulb temperature(DT) and globe temperature(GT) were recorded every minute from June to October 2009 at a height of 1.2m above ten experimental beds with different pavements, by a measuring system consisting of an electric humidity sensor(GHM-15), resistance temperature detector(RTD, Pt-100), standard black globe(${\phi} 150mm$) and data acquisition systems(National Instrument's Labview and Compact FieldPoint). Additionally, the surface dry-bulb temperatures also were recorded and compared. The area of each experimental bed was 1.5m(W)${\times}$2.0m(L) and ten different kinds of pavement were used including grass, grass+cubic stone, grass+porous brick, brick, stone panels, cubic stone, interlocking blocks, clay brick, naked soil, gravel and concrete. To prevent interference from ventilation, a 1.5m height cubic steel frame was established around each bed and each vertical side of the frame was covered with transparent polyethylene film. Based on the records of the hottest period from noon to 3 PM on 26 days with a peak dry-bulb temperature over $30^{\circ}C$ at natural condition, the wet-bulb temperature(WT) and WBGT were calculated and compared. The major findings were as follows: 1. The average surface DT was $40.1^{\circ}C$, which is $9^{\circ}C$ higher than that of the natural condition. The surface DT of the pavements with grass were higher than those of concrete and interlocking block. The peak DT of the surface almost every pavement rose to above $50^{\circ}C$ during the hottest time. 2. The averages of DT, WT and GT were $40.1^{\circ}C$, $27.5^{\circ}C$ and $49.1^{\circ}C$, and the peak values rose to $48.1^{\circ}C$, $45.8^{\circ}C$ and $59.5^{\circ}C$, respectively. In spite of slight differences that resulted according to pavements, no coherent differentiating factor could be found. 3. The average WBGT of grass was the highest at $34.3^{\circ}C$ while the others were similar in the range of around $33{\pm}1^{\circ}C$. Meanwhile, the peak WBGT was highest with stone panel at $47.9^{\circ}C$. Though there were some differences according to pavements, and while grass seemed to be worst in terms of WBGT, it seems difficult to say ablolutely that grass was the worst because the measurement was conducted without ventilation and shade during summer daytime hours only, which had temperatures that rose to a dangerous degree(above $45^{\circ}C$ WBGT), withering the grass during the hottest period. The average WBGT resulted also showed that the thermal environment of the pavement without ventilation and shade were at an intolerable level for humans regardless of the pavement type. In summary, the results of this study show that ventilation and shade are more important factor than pavement type in terms of outdoor thermal comfort in summer daylight hours.

• Journal of radiological science and technology
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• v.36 no.4
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• pp.313-318
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• 2013

Positron emission tomography/computed tomography (PET/CT) imaging with fluorodeoxyglucose (FDG) have been used as a powerful fusion modality in nuclear medicine not only for detecting cancer but also for staging and therapy monitoring. Nevertheless, there are various causes of FDG uptake in normal and/or benign tissues. The purpose of present study was to investigate whether additional delayed imaging can improve the diagnosis to differentiate the rates of FDG uptake at axillary lymph nodes (ALN) between malignant and benign in breast cancer patients. 180 PET/CT images were obtained for 27 patients with ALN uptake. The patients who had radiotherapy and chemotherapy were excluded from the study. $^{18}F$-FDG PET/CT scan at 50 min (early phase) and 90 min (delayed phase) after $^{18}F$-FDG injection were included in this retrospective study. The staging of cancers was confirmed by final clinical according to radiologic follow-up and pathologic findings. The standardized uptake value (SUV) of ALN was measured at the Syngo Acquisition Workplace by Siemens. The 27 patients included 18 malignant and 9 ALN benign groups and the 18 malignant groups were classified into the 3 groups according to number of metastatic ALN in each patient. ALNs were categorized less than or equal 3 as N1, between 4 to 9 as N2 and more than 10 as N3 group. Results are expressed as the mean${\pm}$standard deviation (S.D.) and statistically analyzed by SPSS. As a result, Retention index (RI-SUV max) in metastasis was significantly higher than that in non-metastasis about 5 fold increased. On the other hand, RI-SUV max in N group tended to decrease gradually from N1 to N3. However, we could not prove significance statistically in malignant group with ANOVA. As a consequence, RI-SUV max was good indicator for differentiating ALN positive group from node negative group in breast cancer patients. These results show that dual-time-point scan appears to be useful in distinguishing malignant from benign.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.669-678
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• 1996

Helicobacter pylori is now recognized as causative agent of chronic gastritis and peptic ulcer, and strongly associated with development of gastric carcinoma. With development of sensitive and specific serologic tests to identify individuals infected with Helicobacter pylori, the epidemiologic study of this diseases has been investigated. But it's transmission route is not established, yet. The purpose of this study is to measure the prevalence of Helicobacter pylori infection in healthy children and young adults and to evaluate related factors for Helicobacter pylori infection in Korea. The seroprevalence of Ig G antibodies to Helicobacter pylori was determined using a Enzyme Linked Immunosorbent Assay and we obtained the information, such as demographic characteristics, monthly household income, numbers of family members in the house, numbers of persons using same room, type of house, and type of drinking water through the questionnaire survey. The observed overall seropositivity rate was 25.7%. The rate is increased progressively from 5.8% in the age group $1\sim3$ years to 44.4% in the age group $20\sim29$years($\chi^2$ for trend, p<0.001). Especially, the rate increased steeply from 6.5% in the age group $4\sim6$ years to 20.8% in the age group $7\sim9$ years, and this suggested that elementary school age was the major acquisition time of Helicobacter pylori infection. In multivariate logistic regression model, age, numbers of family members in the house, and type of house was statistically significant variables for Helicobacter pylori infection. Each odds ratio(93% CI) were as follows; base to age group $1\sim9$ years, age group $10\sim19$ years $3.6(2.0\sim6.4)$, age group $20\sim29$ years $7.3(4.1\sim13.1)$ and base to group of $1\sim3$ family members, group of $4\sim5$ family members $2.1(1.1\sim4.0)$, group of 6 or more family members $2.7(1.3\sim5.4)$ and base to apartment, single and multihouse $1.9(1.1\sim3.5)$. Sex, monthly household income, numbers of persons using same room, and type of drinking water was not statistically significant for Helicobacter pylori infection.

• Radiation Oncology Journal
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• v.21 no.1
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• pp.100-106
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• 2003

Purpose : To develop a patients' setup verification tool (PSVT) to verify the alignment of the machine and the target isocenters, and the reproduclbility of patients' setup for three dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT). The utilization of this system is evaluated through phantom and patient case studies. Materials and methods : We developed and clinically tested a new method for patients' setup verification, using digitally reconstructed radiography (DRR), simulation, porial and digital images. The PSVT system was networked to a Pentium PC for the transmission of the acquired images to the PC for analysis. To verify the alignment of the machine and target isocenters, orthogonal pairs of simulation images were used as verification images. Errors in the isocenter alignment were measured by comparing the verification images with DRR of CT Images. Orthogonal films were taken of all the patients once a week. These verification films were compared with the DRR were used for the treatment setup. By performing this procedure every treatment, using humanoid phantom and patient cases, the errors of localization can be analyzed, with adjustments made from the translation. The reproducibility of the patients' setup was verified using portal and digital images. Results : The PSVT system was developed to verify the alignment of the machine and the target isocenters, and the reproducibility of the patients' setup for 3DCRT and IMRT. The results show that the localization errors are 0.8$\pm$0.2 mm (AP) and 1.0$\pm$0.3 mm (Lateral) in the cases relating to the brain and 1.1$\pm$0.5 mm (AP) and 1.0$\pm$0.6 mm (Lateral) in the cases relating to the pelvis. The reproducibility of the patients' setup was verified by visualization, using real-time image acquisition, leading to the practical utilization of our software Conclusions : A PSVT system was developed for the verification of the alignment between machine and the target isocenters, and the reproduclbility of the patients' setup in 3DCRT and IMRT. With adjustment of the completed GUI-based algorithm, and a good quality DRR image, our software may be used for clinical applications.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.523-532
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• 2007

This study utilized the 1/25,000 topographic map of the upper area from the Geum-ho watermark located at the middle of Geum-ho river from the National Geographic Information Institute. For the analysis, first, the influence of the size of critical area to the hydro topographic factors was examined changing grid size to $10m{\times}10m,\;30m{\times}30m\;and\;50m{\times}50m$, and the critical area for the formation of a river to $0.01km^2{\sim}0.50km^2$. It is known from the examination result of watershed morphology according to the grid size that the smaller grid size, the better resolution and accuracy. And it is found, from the analysis result of the degree of the river according to the minimum critical area for each grid size, that the grid size does not affect on the degree of the river, and the number of rivers with 2nd and higher degree does not show remarkable difference while there is big difference in the number of 1st degree rivers. From the results above, it is thought that the critical area of $0.15km^2{\sim}0.20km^2$ is appropriate for formation of a river being irrelevant to the grid size in extraction of hydro topographic parameters that are used in the runoff analysis model using topographic maps. Therefore, the GIUH model applied analysis results by use of the river level difference law proposed in this study for the explanation on the outflow response-changing characters according to the decision of a critical value of a minimum level difference river, showed that, since an ogival occurrence time and an ogival flow volume are very significant in a flood occurrence in case of not undertow facilities, the researcher could obtain a good result for the forecast of river outflow when considering a convenient application of the model and an easy acquisition of data, so it's judged that this model is proper as an algorism for the decision of a critical value of a river basin.

• Journal of National Security and Military Science
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• s.9
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• pp.313-340
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• 2011

The National Defense Reformation bill of "National Defense Reformation 2020" which have been constantly disputed and reformed by the government went through various levels of complementary measures after the North Korean sinking on the Republic of Korea (ROK) Naval Vessel "Cheonan". The final outcome of this reform is also known as the 307 Plan and this was announced on the 8th March. The reformed National Defense Reformation is to reduce the number of units and military personnel under the military structure reformation. However, in order for us to undertake successful National Defense Reformation, the use of privatized civilian resources are essential. Therefore according to this theory, the ROK Ministry of National Defense (MND) have selected the usage of privatized resources as one of the main core agenda for the National Defense Reformation management procedures, and under this agenda the MND plans to further expand the usage of private Especially the MND plans to minimize the personnel resources applied in non-combat areas and in turn use these supplemented personnel with optimization. In order to do this, the MND have initiated necessary appropriate analysis over the whole national defense section by understanding various projects and acquisition requests required by each militaries and civilian research institutions. However for efficient management of privatized civilian resources, first of all, those possible efficient private resources which can achieve optimization will need to be identified, and secondly continuous systematic reinforcements will need to be made in private resource usage legislations. Furthermore, we would need to consider the possibility of labor disputes because of privatization expansion. Therefore, full legal and systematic complementary measures are required in all possible issue arising areas which can affect the combat readiness posture. There is another problem of huge increase in operational expenses as reduction of standby forces are only reducing the number of soldiers and filling these numbers with more cost expensive commissioned officers. However, to overcome this problem, we would need to reduce the number of positions available for active officers and fill these positions with military reserve personnel who previously had working experiences with the related positions (thereby guaranteeing active officers re-employment after completing active service). This would in tum maintain the standards of combat readiness posture and reduce necessary financial budgets which may newly arise. The area of maintenance, supply, transportation, training & education duties which are highly efficient when using privatized resources, will need to be transformed from military management based to civilian management based system. For maintenance, this can be processed by integrating National Maintenance Support System. In order for us to undertake this procedure, we would need to develop maintenance units which are possible to be privatized and this will in turn reduce the military personnel executing job duties, improve service quality and prevent duplicate investments etc. For supply area, we will need to establish Integrated Military Logistics Center in-connection with national and civilian logistics system. This will in turn reduce the logistics time frame as well as required personnel and equipments. In terms of transportation, we will need to further expand the renting and leasing system. This will need to be executed by integrating the National Defense Transportation Information System which will in turn reduce the required personnel and financial budgets. Finally for training and education, retired military personnel can be employed as training instructors and at the military academy, further expansion in the number of civilian professors can be employed in-connection with National Defense Reformation. In other words, more active privatized civilian resources will need to be managed and used for National Defense Reformation.

• Progress in Medical Physics
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• v.26 no.4
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• pp.258-266
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• 2015

The modern radiotherapy technique which delivers a large amount of dose to patients asks to confirm the positions of patients or tumors more accurately by using X-ray projection images of high-definition. However, a rapid increase in patient's exposure and image information for CT image acquisition may be additional burden on the patient. In this study, by introducing structural similarity (SSIM) index that can effectively extract the structural information of the image, we analyze the differences between daily acquired x-ray images of a patient to verify the accuracy of patient positioning. First, for simulating a moving target, the spherical computational phantoms changing the sizes and positions were created to acquire projected images. Differences between the images were automatically detected and analyzed by extracting their SSIM values. In addition, as a clinical test, differences between daily acquired x-ray images of a patient for 12 days were detected in the same way. As a result, we confirmed that the SSIM index was changed in the range of 0.85~1 (0.006~1 when a region of interest (ROI) was applied) as the sizes or positions of the phantom changed. The SSIM was more sensitive to the change of the phantom when the ROI was limited to the phantom itself. In the clinical test, the daily change of patient positions was 0.799~0.853 in SSIM values, those well described differences among images. Therefore, we expect that SSIM index can provide an objective and quantitative technique to verify the patient position using simple x-ray images, instead of time and cost intensive three-dimensional x-ray images.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.2
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• pp.67-80
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• 2020

This study has been conducted at a time when Korean government continues to extend support for youth startups as part of its policy to create jobs and the focus moves from career and employment to youth startups with a growing interest in the field of youth startups. Against this background, this study aims to identify difficulty factors of youth startups in areas besides the Seoul Metropolitan Area, seek ways to overcome difficulty factors, and propose policy implications. To this end, this study set five criteria and 25 sub-criteria to evaluate the difficulties of youth startups by reviewing previous studies and conducting literature review, and performing brainstorming method. The empirical analysis of the evaluation criteria was performed, using the analytic hierarchy process (AHP) method, on youths aged 19 to 39 in Gunsan area. The analysis results showed that the largest difficulty factors facing local youths include business model establishment, business administration and management, and startup funding in the criteria. As for sub-criteria, the largest difficulty factors are market information acquisition, technology commercialization, project feasibility, technology development, and new market pioneering in descending order. Local youths have much difficulty about the process of turning a business item into a product and commercializing it. According to a comparative analysis by gender, men were a relatively high difficulty in commercializing business models than women. men were a relatively high difficulty in commercializing business models than women. On the other hand, women were higher than men in all factors (management management, entrepreneurship, improvement of entrepreneurship system, and improvement of entrepreneurship awareness) except for factors affecting business model. In addition, the factors of entrepreneurship were found to be relatively different among young people (college students, prospective entrepreneurs, entrepreneurs). In conclusion, it was suggested that in order to revitalize youth entrepreneurship in the region, it is necessary to actively resolve the difficulties of business model commercialization rather than entrepreneurship funds. In addition, it is necessary to strategically support customized entrepreneurship support and situational administrative services because gender and hierarchical difficulties are different than general solutions. This study presented practical priorities and derivation methods for the entrepreneurship difficulties faced by local youth, and suggested measures and improvements for vitalizing local youth entrepreneurship in the future.

• Journal of the Korean Society for Library and Information Science
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• v.30 no.1
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• pp.89-123
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• 1996

The world has moved from the Cold War between the east and the west and moved toward the age without idealogy. It places emphasis on economic benefit and welfare of its own nation as its main point With this world trend, in order to sam the competitiveness and the reconciliation of the divided nation the north and the south Korea should be united. Once the north and the south are united, information society will be altered with the huge flow of the civilization. At the same time, the issue of how to operate library policies and system, in which effective acquisition, manipulation, accumulation, and dissemination of information un would be very important. From this point of view, the following conclusions are obtained in this study. Firstly, when building a national library preparing for the national unification. it is essential to introduce 1) the concept of policy and system for information society and 2) that of policy and system which has national-culture as its focus. Secondly, it is essential to prepare the cooperative-structure between libraries prior to the national unification. This kind of cooperation should gradually expand to an extent that allows actual benefits such as building union catalog, inter-library loan system, resource sharing, standardized cataloging rules, and exchange of dissertation... etc. Thirdly, developing the library policies and systems for the national unification must be based on the concept of the mutual cooperation as inter-dependent model rather than on the concept of the incorporation-absorption as a dominant model. The next point the principles of the followings in preparing the library policies should be considered: 1) free-competition, 2) revolution of consciousness through the social education, 3) independence and love for humanity, 4) scientific or reasonable thinking, 5) job responsibility, 6) democratic citizenship, 7) mind far collective life, 8) spirit of public interest 9) globalization In addition, the model of the library systems preparing for thenational unification should include the followings : 1) uniformity of library system and its authority, 2) establishment of research institutes for library policy and system, 3) exchange of library establishment and information resources, 4) building library networks, 5) establishment of education systems for the library and information science and enhancement of its quality, 6) modernizing and developing information technology and its transfer. Finally, the libraries in the north and the south has different concepts, goals, information resources, and the different ways of using them. Considering the practical aspects of the libraries and the reasons for their existence, they must structure the mutual cooperative system so as to minimize the shock when confronting the social changes, so-called the national unification.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.55-64
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• 2017

Purpose Recently, with the spread of SPECT/CT, various image correction methods can be applied quickly and accurately, which enabled us to expect quantitative accuracy as well as image quality improvement. Among them, the Collimator Detector Response(CDR) recovery is a correction method aiming at resolution recovery by compensating the blurring effect generated from the distance between the detector and the object. The purpose of this study is to find out quantitative change depending on the change in detection distance in SPECT/CT images with CDR recovery applied. Materials and Methods In order to find out the error of acquisition count depending on the change of detection distance, we set the detection distance according to the obit type as X, Y axis radius 30cm for circular, X, Y axis radius 21cm, 10cm for non-circular and non-circular auto(=auto body contouring, ABC_spacing limit 1cm) and applied reconstruction methods by dividing them into Astonish(3D-OSEM with CDR recovery) and OSEM(w/o CDR recovery) to find out the difference in activity recovery depending on the use of CDR recovery. At this time, attenuation correction, scatter correction, and decay correction were applied to all images. For the quantitative evaluation, calibration scan(cylindrical phantom, $^{99m}TcO_4$ 123.3 MBq, water 9293 ml) was obtained for the purpose of calculating the calibration factor(CF). For the phantom scan, a 50 cc syringe was filled with 31 ml of water and a phantom image was obtained by setting $^{99m}TcO_4$ 123.3 MBq. We set the VOI(volume of interest) in the entire volume of the syringe in the phantom image to measure total counts for each condition and obtained the error of the measured value against true value set by setting CF to check the quantitative accuracy according to the correction. Results The calculated CF was 154.28 (Bq/ml/cps/ml) and the measured values against true values in each conditional image were analyzed to be circular 87.5%, non-circular 90.1%, ABC 91.3% and circular 93.6%, non-circular 93.6%, ABC 93.9% in OSEM and Astonish, respectively. The closer the detection distance, the higher the accuracy of OSEM, and Astonish showed almost similar values regardless of distance. The error was the largest in the OSEM circular(-13.5%) and the smallest in the Astonish ABC(-6.1%). Conclusion SPECT/CT images showed that when the distance compensation is made through the application of CDR recovery, the detection distance shows almost the same quantitative accuracy as the proximity detection even under the distant condition, and accurate correction is possible without being affected by the change in detection distance.