• Journal of the Korean Wood Science and Technology
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• v.40 no.6
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• pp.370-377
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• 2012

This study was conducted to investigate the color change of heat-treated wood made of Korean pine (Pinus koraiensis S. et Z.), and lodgepole pine (Pinus contorta Dougl). The wood samples were heat-treated at 9 different treatment combinations of temperature (170, 180, 200, 220, and $230^{\circ}C$), and time (90, 120, 180, 240, 270 min.) set up by a response surface method. Wood color was measured using a colorimeter, and the samples were installed for evaluating the resistance of termite in the field test sites set up in Jinju. The lightness decreased with the increase of treatment temperature and treatment time. The color differences were evaluated by the method of National Bureau of Standards (NBS), and response surface models to predict the color change were fitted as a function of treatment temperature and treatment time. The $R^2$ values of the fitted models of heat-treated Korean pine and lodgepole pines were 0.92, and 0.88, respectively, showing the potential way for the prediction of color changes. Severe damage was found from the samples in the field test site, which means that the manufactured heat-treated wood did not show the termite resistance enough for the outdoor use.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.139-151
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• 2018

Objectives : A self-made "Tomotherapy couch device" capable of correcting the Yaw direction was fabricated and evaluated for its usefulness. Materials and Methods : "Tomotherapy couch device" capable of correcting the Yaw direction is made of rigid fibreboard with a flexural strength of $200kg/cm^2$. CBCT Image from Novalis Tx and Iso-Align Phantom from MED-TEC were used to evaluate the physical accuracy. The treatment plan was designed using Accuray $Precision^{TM}$ and In House Head and Phantom. Accuray $PrecisionART^{TM}$ and $Precision^{TM}$ was used to evaluate dose. Results : Evaluation results, the self-fabricated device accurately corrected the setup error, Target dose was within 95 %~107 % of all. In order to directly evaluate the OAR dose according to the Yaw change, the absolute dose was measured. As a result, when the error in the Yaw direction was $3^{\circ}$, the specific OAR showed a maximum difference of 18.4 %. Conclusion : "Tomotherapy couch device" capable of correcting the Yaw direction can be manufactured at a lower cost compared to the effect, and it can prevent the patient's MVCT image dose for re-imaging. Accurate radiation therapy without errors can be performed.

• 유학연구
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• v.46
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• pp.1-24
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• 2019

Gocheong Seogee is a Confucian scholar in the mid-Joseon period during which Confucian philosophy is not completely established as a national discipline. He was an authentic Seon-bi who helped boost Confusion philosophy in southern and northern parts of Chungcheong area including Daejeon, Nonsan, Gongjoo, Buyeo, Hongseong, Jochiwon as well as Boryeong and Dangjin. Following Seogee, Jangsaeng Kim, who had studied under Yulgok, strived to firm up Giho Confusion philosophy there. Influenced by his teacher Geeham Lee's pragmatical school whose main principle is loyal to their country and affectionate to their people, Seogee set his heart on living up to the same path as previous holy men had gone through rather than pursuing an overly speculative school only focused on Confucian scriptures. He seems to have put the virtues of pragmatic Confusion scholars into practice in accordance with the way Confucius and Mencius devoted themselves to their study and learning. He carried Hyangyak into effect, built the first Seowon in Chungnam area called Chunghyeon Seowon emulating Zhu Xi's Baeklokdong Seowon, and paid close attention to learning with Zhu Xi's portrait enshrined. Those things attest that he eagerly strive to put Confucianism into practice. Through these efforts, he gave a significant influence on establishing Confusion philosophy in southern and northern parts of Chungcheong area and trained lots of disciples like Leechang Song, Jaemoon Min - the teacher of Choryeo Yootae Lee - and so on. As a result, he laid a big foundation stone to develop Confusion culture in Naepo region. Therefore, his position should seem to be re-evaluated in Korean Confucian history. In a rigidly hierarchical social structure, he studied and interacted alongside with Geeham Lee, Heon Jo, Ikpeel Song, Sik Jo, and others with no thought of their lower social status and without any academic prejudices. These kinds of his mind-set and attitudes seem to be a precious example of embodying real Seon-bi spirit. So, I suggest Seogee's life has a substantial significance in strengthening personality education of the young today and composing media contents of local community.

• The Journal of Korean Society for Radiation Therapy
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• v.23 no.1
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• pp.1-6
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• 2011

Purpose: Immobilizations used in order to maintain the reproducibility of a patient set-up and the stable posture for a long period are important more than anything else for the accurate treatment when the stereotactic body radiotherapy is underway. So the purpose of this study is to adapt the optimum immobilizations for the stereotactic body radiotherapy by comparing two commercial immobilizations with the self-manufactured immobilizations. Materials and Methods: Five people were selected for the experiment and three different immobilizations (A: Wing-board, B: BodyFix system, C: Arm up holder with vac-lock) were used to each target. After deciding on the target's most stable respiratory cycles, the targets were asked to wear a goggle monitor and maintain their respiration regularly for thirty minutes to obtain the respiratory signals. To analyze the respiratory signal, the standard deviation and the variation value of the peak value and the valley value of the respiratory signal were separated by time zone with the self-developed program at the hospital and each tie-downs were compared for the estimation by calculating a comparative index using the above. Results: The stability of each immobilizations were measured in consideration of deviation changes studied in each respiratory time lapse. Comparative indexes of each immobilizations of each experimenter are shown to be A: 11.20, B: 4.87, C: 1.63 / A: 3.94, B: 0.67, C: 0.13 / A: 2.41, B: 0.29, C: 0.04 / A: 0.16, B: 0.19, C: 0.007 / A: 35.70, B: 2.37, C: 1.86. And when all five experimenters wore the immobilizations C, the test proved the most stable value while four people wearing A and one man wearing D expressed relatively the most unstable respiratory outcomes. Conclusion: The self-developed immobilizations, so called the arm up holder vac-lock for the stereotactic body radiotherapy is expected to improve the effect of the treatment by decreasing the intra-fraction organ motions because it keeps the respiration more stable than other two immobilizations. Particularly in case of the stereotactic body therapy which requires the maintenance of set-up state for a long time, the self-developed immobilizations is thought to more useful for stereotactic body radiotherapy rather than the rest two immobilizations with instable respiratory cycle as time passes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.4
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• pp.589-598
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• 2000

A pilot-scale Spray Drying Sorber (SDS) system was set up to evaluate the effect of spray characteristics on the desulfurization yield. The size distribution and the Sauter Mean Diameters of slurry droplets were measured in advance using the optical size measurement system, Malvern 2600. The desulfurization yield of the drying chamber by size was measured for the conditions of inlet gas and spray injection. As a reagent, 10% limestone slurry of $Ca(OH)_2$ was treated with flue gas containing $SO_2$, and the combustion gas analyzer and gas detectors were attached to measure the $SO_2$ concentration. With a flow rate of 144 Nm3/h and a temperature range of $200{\sim}300^{\circ}C$, the experiments were performed for the Stoichiometric Ratio (SR) of 1.0 to 3.0 and droplet mean diameter of 6.5 to $34.3{\mu}m$. In case of smaller spray droplets, the desulfurization efficiency improved due to the increase of total droplet surface area, while the reduction in evaporation time reduced the contact time between the droplets and $SO_2$ gas. In some typical region of droplet diameter, this negative effect, reduction of contact time, became dominant and the desulfurization yield decreases the desulfurization yield in spite of the expansion in absorption area. These results revealed that there exists the optimal size of spray droplets for a given state, which is determined by the compromise between the total surface area of slurry droplets and the evaporation time of droplets. The measurements also indicated that the inlet temperature of flue gas changes the optimal injection condition by varying the driving force for evaporation. The results confirm that the effect of the evaporation time of slurry droplets should be considered in analyzing the desulfurization yield as well as the total surface area, for it is a significant aspect of the correlation with the capabilities of $SO_2$ absorption in wet droplets. In conclusion, the optimal condition of spray can be determined based on these results, which might be applied to design or scale-up of SDS system.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.12
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• pp.1891-1902
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• 2008

With concerns for consumers' return behaviors affecting internet shopping malls' profits and product management in the internet clothing market, this study is designed to investigate determinants affecting return and path models for return behaviors. For an empirical study, questionnaires are prepared and respondents in their 20s and 30s with internet clothing purchase experience are selected using the convenience sampling. A total of 517 questionnaires are used for the final analysis. Data are analyzed by using SPSS 12.0 software and descriptive statistics, $x^2$-test, discriminant analysis, regression analysis, and path analysis is conducted. The results are as follows. First, ones who have returned after purchasing clothing items in internet shopping reached 63.4% of the total consumers. Respondents returned items with price at 50 thousand won or less stood at 67.2%, and the most frequent return shopping malls are open markets with their return rate at 51.1%. Second, variables such as risk perception, information search, impulse buying, buying experience, and age have a positive effect on return experience. Impulse buying and buying experience turn out to have a significant effect on the degree of return, but risk perception, information search, age, and gender to have an insignificant effect. Return intention is significantly affected by risk perception, gender, and age. Third, the analysis of path model for return experience shows that perceived risk has a positively effect, and information search has a direct effect as well as an indirect effect through buying experience or impulse buying. The analysis of path model for the degree of return shows that risk perception does not have effect, but information search has indirect effect through buying experience or impulse buying. This study is thought to find consumers' return behavior characteristics in online shopping, and help businesses operating online shopping malls to efficiently manage returns and set up strategies against returns.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.777-782
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• 2002

Reciprocal effects among local breeds and additive and heterosis effects were estimated for total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). Procedures for an optimum crossbreeding system were examined by comparing various crossbred combinations. Three data sets were chosen from the total records collected from 1962 to 1997. Data set I with a total of 5,938 records composed of 9 breed groups for reciprocal crosses, data set II with a total of 6,064 records composed of 5 breed groups for additive and heterosis effects and data set III with a total of 10,319 records composed of 42 breed groups for optimum crossbreeding system were analyzed. The least squares ANOVA was used. The reciprocal crosses between Red Sindhi and the Bangladeshi Local showed significant difference. When the Red Sindhi was used as cow, the cross was superior to the opposite in terms of the three performance traits. The results showed that additive breed effects on both TLP and DMY were positive and highly significant between Bos indicus and Bos taurus, whereas the individual heterosis effects were not significant. In general, any local breeds were improved two to three times by crossing with the Friesian once or twice. However, the effect was reduced when the grading up with the Friesian was repeated more than twice. On the other hand, when the local breed was crossed with the other breeds such as Holstein and Jersey, the improvement of TLP was less. Crossing the F1 cows with the Friesian bull gave further improvement. Almost the same trends were found also for LL and DMY. The local breeds and their crosses are raised mainly for draft animals, then it is recommended that the crossbreds between the local cows and Friesian are used for dairy purposes and more than 75% Friesian blood is used for beef.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.2
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• pp.35-42
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• 2014

The purpose of this study is to analyze job stress factors of hospital workers, which has an effect on their turnover intention. For identifying the influences on turnover intention, types of hospitals (university hospital, general hospital, private hospital) and types of workers(office workers, technical workers, and nursing staffs) were categorized. We went to the hospitals and carried out the survey under the cooperation with the concerned hospitals. The period of survey was from 23. Sep. 2013 to 30. Oct. 2013, and 293 worker participated in the survey. On the basis of the previous study, the measurement of job stress factors and turnover intention was set up as the survey method, and its reliability and validity were measured. The stress factors were subdivided into seven factors; occupational climate, organizational system, autonomy job control, uncertainty of getting a new job, job ability to perform, job demand, job ambiance. The value of job stress factors by the measuring instrument, Cronbach's Alpha, was 0.805 and the value of the subordination variable of turnover intention was 0.881. IBM SPSS Statistics 21 was used as the statistic analysis tool and the descriptive statistics about job stress factors. As a result, the turnover intention were analyzed depending on the types of hospitals, job groups, working years, and gender. Result shows that the job stress factors are differed according to the types of hospitals, and these job stress factors have influence on turnover intention. Therefore, it could be considered that, if the hospital managers find out the major job stress factors of their employees and resolve them in advance, the job stress of the hospital workers and their turnover intention can be reduced.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.6
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• pp.413-422
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• 2013

In this paper, we propose a novel method for real-time lane detection that is robust for inclined roads and not require a camera parameter, the Inverse Perspective Transform of the image, and the proposed lane filter. After finding the vanishing point from the start frame of the image and storing the region surrounding the vanishing point as the Template Area(TA), our method predict the lanes by scanning toward the lower part from the vanishing point of the image and obtain the image removed the perspective effect using the Inverse Perspective Transform coefficients extracted based on the predicted lanes. To robustly determine lanes on inclined roads, the region surrounding the vanishing point is set up as the template area (TA), and, by recalculating the vanishing point by tracing the area similar to the TA (SA) in the input image through template matching, it responds to the changes on the road conditions. The proposed method for a more robust lane detection method for inclined roads is a lane detection method by applying a lane detection filter on an image removed of the perspective effect. Through this method, the processing region is reduced and the processing procedure is simplified to produce a satisfactory lane detection result of about 40 frames per second.

• KIEAE Journal
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• v.11 no.5
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• pp.13-18
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• 2011

The overall aim of this study is to mitigate urban environmental problems. In particular, to reduce the effects of urban heat island phenomenon which is one of the urban planning perspective. This study focused on the analysis of the relationship between the urban heat island effect and the thermal and wind properties. To do this analysis, water space was virtually made at Yeol_Mae village Apt. Because it is very difficult to set up water space for the existing apartment complexes due to realistic constraints. This study, therefore has a strong sort of guidelines to create water space for newly formed city. It was based on the concept of virtual city through an in-depth analysis on reduction of urban heat island effects for the existing apartment along with creation of water space. To analysis site, Envi-Met Model developed by Michael Bruse was used. The results are as follows. The temperature went from 298.9K to 297.82K and The wind speed went from 1.42m/s to 1.43m/s. The results are slight in this study because creation of water space is planned to a small area of an apartment complex. But if the water space would be applied to a whole city, the mitigation effect of urban heat island would be bigger.