• Journal of Ecology and Environment
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• v.42 no.4
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• pp.272-277
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• 2018

Background: Studying the ecosystem carbon cycle requires analysis of interrelationships between soil respiration (Rs) and the environment to evaluate the balance. Various methods and instruments have been used to measure Rs. The closed chamber method, which is currently widely used to determine Rs, creates a closed space on the soil surface, measures $CO_2$ concentration in the inner space, and calculates Rs from the increase. Accordingly, the method is divided into automatic or manual chamber methods (ACM and MCM, respectively). However, errors of these methods and differences in instruments are unclear. Therefore, we evaluated the characteristics and difference of Rs values calculated using both methods with actual data. Results: Both methods determined seasonal variation patterns of Rs, reflecting overall changes in soil temperature (Ts). ACM clearly showed detailed changes in Rs, but MCM did not, because such small changes are unknown as Rs values are collected monthly. Additionally, Rs measured using MCM was higher than that using ACM and differed depending on measured plots, but showed similar tendencies with all measurement times and plots. Contrastingly, MCM Rs values in August for plot 4 were very high compared with ACM Rs values because of soil disturbances that easily occur during MCM measurements. Comparing Rs values calculated using monthly means with those calculated using MCM, the ACM calculated values for monthly averages were higher or lower than those of similar measurement times using the MCM. The difference between the ACM and MCM was attributed to greater or lesser differences. These Rs values estimated the carbon released into the atmosphere during measurement periods to be approximately 57% higher with MCM than with ACM, at 5.1 and $7.9C\;ton\;ha^{-1}$, respectively. Conclusion: ACM calculated average values based on various Rs values as high and low for measurement periods, but the MCM produced only specific values for measurement times as representative values. Therefore, MCM may exhibit large errors in selection differences during Rs measurements. Therefore, to reduce this error using MCM, the time and frequency of measurement should be set to obtain Rs under various environmental conditions. Contrastingly, the MCM measurement is obtained during $CO_2$ evaluation in the soil owing to soil disturbance caused by measuring equipment, so close attention should be paid to measurements. This is because the measurement process is disturbed by high $CO_2$ soil concentration, and even small soil disturbances could release high levels into the chamber, causing large Rs errors. Therefore, the MCM should be adequately mastered before using the device to measure Rs.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.1
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• pp.51-66
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• 2022

SST (Sea Surface Temperature) is based on the atmosphere-ocean interaction, one of the most important mechanisms for the Earth system. Because it is a crucial oceanic and meteorological factor for understanding climate change, gap-free grid data at a specific spatial and temporal resolution is beneficial in SST studies. This paper examined the production of daily SST grid maps from 137 stations in 2020 through the ordinary kriging with variogram optimization and their accuracy assessment. The variogram optimization was achieved by WLS (Weighted Least Squares) method, and the blind tests for the interpolation accuracy assessment were conducted by an objective and spatially unbiased sampling scheme. The four-round blind tests showed a pretty high accuracy: a root mean square error between 0.995 and 1.035℃ and a correlation coefficient between 0.981 and 0.982. In terms of season, the accuracy in summer was a bit lower, presumably because of the abrupt change in SST affected by the typhoon. The accuracy was better in the far seas than in the near seas. West Sea showed better accuracy than East or South Sea. It is because the semi-enclosed sea in the near seas can have different physical characteristics. The seasonal and regional factors should be considered for accuracy improvement in future work, and the improved SST can be a member of the SST ensemble around South Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1296-1303
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• 2014

This study was conducted to develop predictive models for the growth of Bacillus cereus on carrot treated with slightly acidic electrolyzed water (SAcEW) and ultrasonication (US) at different storage temperatures. In addition, the inactivation of B. cereus by US with SAcEW was investigated. US treatment with a frequency of 40 kHz and an acoustic energy density of 400 W/L at $40^{\circ}C$ for 3 min showed the maximum reduction of 2.87 log CFU/g B. cereus on carrot, while combined treatment of US (400 W/L, $40^{\circ}C$, 3 min) with SAcEW reached to 3.1 log CFU/g reduction. Growth data of B. cereus on carrot treated with SAcEW and US at different temperatures (4, 10, 15, 20, 25, 30, and $35^{\circ}C$) were collected and used to develop predictive models. The modified Gompertz model was found to be more suitable to describe the growth data. The specific growth rate (SGR) and lag time (LT) obtained from the modified Gompertz model were employed to establish the secondary models. The newly developed secondary models were validated using the root mean square error, bias factor, and accuracy factor. All results of these factors were in the acceptable range of values. After compared SGR and LT of B. cereus on carrot, the results showed that the growth of B. cereus on carrot treated with SAcEW and US was slower than that of single treatment. This result indicates that shelf life of carrot treated with SAcEW and US could be extended. The developed predictive models might also be used to assess the microbiological risk of B. cereus infection in carrot treated with SAcEW and US.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.430-437
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• 2007

The probability table of Moyers and prediction equation of Tanaka and Johnston that have been the most frequently used, cannot produce accurate prediction when used in Korean because they are based on the Caucasian popularity of the Northern European race. The method of Moyers or Tanaka and Johnston predicts sizes of the unerupted canine and premolars on the basis of the sizes of mandibular incisors. However, some of the recent papers raise a question as to whether the mandibular incisors are the best combination to predict the sizes of the unerupted canine and premolars. The purpose of this study is to determine which sum or combination of sums of permanent tooth widths present the best prediction for the unerupted canine and premolars in a Korean sample, to calculate a specific linear regression equation for this population, and to evaluate the clinical significance. A new linear regression equation was calculated based on the data of 178 Korean young adults(70 women, 108 men, mean age 21.63 years) with complete permanent dentitions. Fifty three more children(28 girls, 25 boys, mean age 14.22 years) were used as a validation sample for the application of the multiple linear regression equation. The conclusions were as follows: 1. The combination of the sums of permanent upper central incisors, lower lateral incisors and upper first molars was the best predictor for the unerupted canine and premolars in this sample($r=0.65{\sim}0.80$). 2. The multiple linear regression equation was calculated including sex and arch as additional predictor variables. male, upper: $Y\;=\;0.332{\times}X_0\;+\;6.195$ male, lower: $Y\;=\;0.332{\times}X_0\;+\;5.269$ female, upper: $Y\;=\;0.332{\times}X_0\;+\;5.929$ female, lower: $Y\;=\;0.332{\times}X_0\;+\;5.003$. The determination coefficient of the equation was 64% and a standard error of the estimate was 0.71mm. 3. In about 97% of the validation sample, the estimation of the tooth width sums of unerupted canine and premolars using the new multiple linear regression equation was smaller than 1mm compaired with the actual values.

• Journal of Preventive Medicine and Public Health
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• v.32 no.2
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• pp.177-182
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• 1999

Objectives: To reexamine the association between air pollution and daily mortality in Seoul, Korea using a method of meta-analysis with the data filed for 1991 through 1995. Methods: A separate Poisson regression analysis on each district within the metropolitan area of Seoul was conducted to regress daily death counts on levels of each ambient air pollutant, such as total suspended particulates (TSP), sulfur dioxide $(SO_2)$, and ozone $(O_3)$, controlling for variability in the weather condition. We calculated a weighted mean as a meta-analysis summary of the estimates and its standard error. Results: We found that the p value from each pollutant model to test the homogeneity assumption was small (p<0.01) because of the large disparity among district-specific estimates. Therefore, all results reported here were estimated from the random effect model. Using the weighted mean that we calculated, the mortality at a $100{\mu}g/m^3$ increment in a 3-day moving average of TSP levels was 1.034 (95% Cl 1.009-1.059). The mortality was estimated to increase 6% (95% Cl 3-10%) and 3% (95% Cl 0-6%) with each 50 ppb increase for 9-day moving average of SO2 and 1-hr maximum O3, respectively. Conclusions: Like most of air pollution epidemiologic studies, this meta-analysis cannot avoid fleeing from measurement misclassification since no personal measurement was taken. However, we can expect that a measurement bias be reduced in a district-specific estimate since a monitoring station is hefter representative cf air quality of the matched district. The similar results to those from the previous studios indicated existence of health effect of air pollution at current levels in many industrialized countries, including Korea.

• Journal of the Korean Society of Radiology
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• v.7 no.2
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• pp.157-163
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• 2013

This study was to analyze quantitatively movement of planning target volume (PTV) and change of PTV volume through movement of diaphragm according to breathing phase. The purpose of present study was to investigate optimized respiration phase for radiation therapy of lung cancer. Simulated breathing training was performed in order to minimize systematic errors which is caused non-specific or irregular breathing. We performed 4-dimensional computed tomography (4DCTi) in accordance with each respiratory phase in the normalized respiratory gated radiation therapy procedures, then not only defined PTVi in 0 ~ 90%, 30 ~ 70% and 40 ~ 60% in the reconstructed 4DCTi images but analyzed quantitatively movement and changes of volume in PTVi. As a results, average respiratory cycle was $3.4{\pm}0.5$ seconds by simulated breathing training. R2-value which is expressed as concordance between clinically induced expected value and actual measured value, was almost 1. There was a statistically significant. And also movement of PTVi according to each respiration phase 0 ~ 90%, 30 ~ 70% and 40 ~ 60% were $13.4{\pm}6.4mm$, $6.1{\pm}2.9mm$ and $4.0{\pm}2.1mm$ respectively. Change of volume in PTVi of respiration phase 30 ~ 70% was decreased by $32.6{\pm}8.7%$ and 40 ~ 60% was decreased by $41.6{\pm}6.2%$. In conclusion, PTVi movement and volume change was reduced, when we apply a short breathing phase (40 ~ 60%: 30% duty cycle) range. Furthermore, PTVi margin considered respiration was not only within 4mm but able to get uniformity of dose.

• Journal of Korean Library and Information Science Society
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• v.45 no.1
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• pp.81-102
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• 2014

In 1978, there was an investigation before the repair of the pagoda in Suzhou Ruiguangsi (蘇州 瑞光寺) and many Buddhist literatures were found in the center of pagoda's 3rd floor. This study is the analysis of the forms and values of the literatures. Since there were 123 ea of precious literatures made from Tang (唐) period to early North Sung (北宋) period among the found Buddhist literatures, they have very important meaning in the bibliography for the time. Suzhou Reiguangsi (蘇州 瑞光寺) was built by the first king of Wu (吳), Sun Quan (孫權). He built this Buddhist temple to meet Monk Xingkang (性康) from Kangjuguo (康居國). When it had been first built, it had been called Puji Chanyuan (普濟禪院) and it was renamed as current Ruiguangsi (瑞光寺) after the major expansion in the early period of North Sung (北宋). The Ruiguangta (瑞光塔) was built by Sun Quan (孫權) in A.D. 247 immediately after the temple had been built. Sun Quan built this pagoda as a 13-floor pagoda to pray for the easy passage into eternity of his mother, national prosperity and welfare of the people. As time passed by, the pagoda was largely damaged and it was newly built in A.D. 1017 (天禧 1) of early North Sung (北宋) period; while it was named as Duobaota (多寶塔). The literatures found in Ruiguangta consist of 107 ea of 3 sets dharani (陀羅尼) scripture and 16 volumes of 5 books, total 123 ea. Especially, there were 7 books of full set transcript of Lotus Sutra (法華經) in relatively complete form. This sutra written in gilt lettering on dark blue paper was made in Middle Tang (中唐) period and it is believed to be the only one existing in East Asia as a scripture written in gilt lettering on dark blue paper (紺紙金字寫經). There were also 6 books of small letter edition of Lotus Sutra (法華經) in complete form, which was published during the early North Sung (北宋) period. This specific edition is incorrectly stated in most general reference books published in China as having been engraved in early Tang period (初唐) since a Japanese scholar wrongly introduced it as having been engraved together with Nakamura edition (中村本). It is meaningful that this error can be corrected by the finding of this study.

• Journal of Technologic Dentistry
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• v.24 no.1
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• pp.51-63
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• 2002

The purpose of this study was to be of use for getting rid of job stress from dental technicians, by examining how much they were stressed out at work place as one of the professional medical personnels. The subjects in this study were 255 selected dental technicians who were working in the region of Taegu. The one-on-one interview was conducted from March 1 to 30, 2001, with structured questionnaire. The questionnaire sued in this study included 19 question items about the general characteristics and 29 items regarding job stress. The job stress was categorized into seven subareas based on earlier studies and considering the job situations of dental technicians: heavy workload, job conflicts, improper treatment, role and job knowledge, human relations, physical environment and personal matters. The job stress extent was measured on five-point Likert scale that is widely used in social science: one point for no stress, two for little stress, three for so-so, four for a little stress, and five for severe stress. Therefore, a higher point means a severer job stress. The reliability of the questionnaire turned out very good with Cronbach a = 0.9272. The findings of this study were as follows: 1. The general characteristics of the dental technicians investigated could be described as below: (1) By gender, 80.4% of the dental technicians were male, and 50.2%, the largest percentage, were in their 20s, followed by those in their 30s, those in their 40s, and those in their 50s in the order named. (2) The most common work place was dental technician shop(92.5%), followed by dental technology room in dental hospital or clinic and in general hospital in the order named. The primary duties were coating materials work(30.6%), followed by sculpture, grinding, partial and full denture and orthodontics in the order named. 2. The most larges (1) The most largest motivation to be a dental technician was its being a professional(33.7%), followed by the advice from others, their own aptitude, and good economic treatment in the order named. 3. Their job stress could be explained as below: (1) Their collective job stress average was 3.96$^{\circ}{\ae}$0.50 on the basis of 5 point, which showed that they were exposed to a fairly severe job stress. (2) By area, they were most stressed out from heavy workload (4.12), and they also were severely stressed from role and job knowledge(4.02) and personal matters(4.00). (3) By situation, they were most stressed when the disagreement of prosthesis that results from a specific error is unconditionally attributed to them(4.43). And they were also stressed a lot when their workload increases due to the rework(4.38), when a dentist asks something difficult for them to resolve(4.20), when heavy workload makes their working hours irregular and it's impossible to lead a personal life or have leisure time(4.16), and when they are o work for an excessively short time(4.16). This fact indicated that most of the dental technicians were exposed to a lot of stress in conjunction with job performance. 4. The main duties they took charge of didn't make any significant difference to their job stress, but yielded a significant difference to the extent of job stress in individual areas and the order of the most stressful one. Those who were engaged in grinding were most stressed from their own matters, whereas heavy workload was most stressful for those who were engaged in the other types of works. 5. As a result of seeing if their personal characteristics yielded any differences to job stress, the personal characteristics that made their job stress vary significantly were working hours, motivation of being a dental technician, job satisfaction and willingness to continue doing dental technology works. There was a tendency that longer working hours led to severer job stress, and those who chose to be a dental technician according to their own aptitude were less stressed than the others who became a dental technician because of economic reason or advices from others. And the people who were satisfied with their job were exposed to less job stress than the others who weren't, and those who had an intention to keep that job as much as possible were less stressed, compared to the others who hadn't.

• Journal of Service Research and Studies
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• v.13 no.3
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• pp.160-171
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• 2023

The importance of design utilization as a method for establishing policies and services in the public sector is increasing. Accordingly, Korea has introduced a public service design development method and has implemented and operated a national design group for consumer-centered policy development since 2014. This study analyzes the cases of the National Design Group to expand the use of design in the public sector and propose sustainable public service design strategies. The time range of this study is from 2014 to 2021, when the National Design Group was implemented, and the content is limited to tasks that can be found on the Gwanghwamun 1st Street website and the National Design Group casebook. This study was conducted as follows. First, we looked for implications for how to use and identify the role of design in the public policy development stage by referring to the literature on design policy and public service design, and second, based on major implications, we analyzed the task name and contents. Based on literature studies and case studies, we found implications that design can be used in various public fields, and the policy implications proposed to expand the use of sustainable design in the public sector are as follows. First, by raising awareness of service design in public policies and services, it continues to provide opportunities for the use of design to expand as a role that leads to voluntary behavioral changes of citizens beyond civic participation. Second, more active publicity is needed for the successful cases of the National Design Group, a product of the active use of public service design. Third, a more specific evaluation system should be introduced to verify the effectiveness and effectiveness of public service design. Through this, it is expected that it will greatly contribute to reducing the error in policy delivery and realizing citizen-centered public services by utilizing design for various problems facing our society.