• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.213-219
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• 2012

The $5^{th}$ national forest inventory (NFI5) has been reorganized to annual inventory system for providing multi-resources forest statistics at a point in time. The objective of this study is to evaluate statistical estimators for estimating forest growing stock in Chungcheongbuk-Do from annual inventory data. When comparing two estimators; simple random sampling (SRS) and double sampling for post-stratification (DSS), for estimating mean forest growing stock ($m^3/ha$) at each surveyed year, the estimate for DSS in which a population of interest is stratified into three sub-population (forest cover types) was more precise than that for SRS. To combine annual inventory field data, three estimators (Temporally Indifferent Method; TIM, Moving Average; MA, and Weighted Moving Average; WMA) were compared. Even though the estimated mean for TIM and WMA is identical, WMA-DSS is preferred to provide more smaller variance of estimated mean and to adjust for catastrophic events at a surveyed year (so-called "lag bias") by annual inventory data.

• Korean journal of applied entomology
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• v.26 no.2 s.71
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• pp.99-106
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• 1987

Three post-harvest fields each in four rice growing areas, Iri, Naju, Jinju and Taegu were randomly selected and surveyed during December 1986 to examine sclerotial density of Rhizoctonia solani overwintering in the field. Surface soil of $0.09m^2$ area was sampled in each field with three replications and sieved to collect sclerotia. Germiability and pathogenicity of collected sclerotia were examined in the laboratory. Number of sclerotia $({\times}10^6)/ha$ in Iri, Naju, Jinju, and Taegu was estimated from the sample as 2.7, 1.2, 0.7 and 0.6, respectively. Based on sample variance with simple random sampling in each area, number of sampling required for estimating average sclerotial density with the precision of 10% apart from a chance of 1 in 20 was calculated to 41, 132, 232, and 395 for Iri, Naju, Jinju and Taegu, respectively. Percentage of germination of sampled sclerotia on potato sucrose agar (PSA) ranged from 42 to 78% depending on the area, and averaged 60%. About 49% of the germinated sclerotia were pathogenic to a rice cultivar Jinheung that was used to test pathogenicity of the sclerotia. Proportion of viable sclerotia that have both germiability and pathogenicity was thus estimated to 0.29 of total sclerotia collected. R. solani cultures obtained from the sclerotia could be distinguished into three groups based on colony morphology on PSA. Size and number of sclerotia formed on PSA differed between group but were not associated with pathogenicity to Jinheung.

• Journal of Distribution Science
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• v.12 no.4
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• pp.41-46
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• 2014

Purpose - This study focused on providing strategic findings that make significant sense for companies that are looking for a future outsourcing strategy. The study analyzes the results of outsourcing in the information logistics systems field and verifies the results through experimental study of the performance delivered by logistics outsourcing types. Research design, data, and methodology - The study sample was assembled based on a random sampling method used to extract the initial 451 companies from a list of Korean distributors, wholesalers, and retailers. Following that sample process, 423 companies were confirmed by verifying their e-mail address and contacts (telephone and fax numbers), and were selected as initial research subjects. We reduced that number to 331 companies for the survey sample through telephone interviews in advance with the 423 companies that were targeted, in order to verify whether they are in the field of outsourcing of information logistics systems. The period of the survey extended from November 10, 2013 to January 10, 2014. The number of collected surveys totaled 181. We reviewed the contents of the survey responses, and reduced the number of research subjects to 175. In this study, we used a standard analysis to investigate whether there is a difference in distribution results based on different types of outsourcing information in the logistics system field and, through T-verification, we investigated whether the difference between distribution results in each group resulting from that standard analysis is statistically significant. Results - These results show that there is a difference in distribution outcome, based upon type of distribution outsourcing. In addition, we determined that they are meaningful results by confirming that, for usability and to improve the capabilities of a third-party logistics service supplier, both the choice of reasonable outsourcing types and the enhancement of various types of alliances are very important success factors. Taken together these study results, with a goal of enhancing the distribution capabilities of a Korean distributor, can be implemented to enhance management results achievable by supplying an information logistics system in the form of strategic outsourcing rather than in the form of simple outsourcing. In addition, the outcomes of logistics distributors in Korea that are using outsourcing in the logistics information systems field show high performance results in commercial endeavors in the following order: competitive, pre-competitive, non-competitive, and pro-competitive. Conclusions - This study focused on providing strategic findings. However, in the case of outsourcing in the field of information logistics systems of Korean distributors, there has been a focus on simple outsourcing rather than on strategic outsourcing; furthermore, there has been a concentration on non-competitive forms instead of pro-competitive forms, which could achieve better distribution results. This discussion is presented in more detail in the analysis results of this study.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.3
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• pp.181-194
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• 2017

This study aims to develop a regression model for forest volume estimation using field-collected forest inventory information and airborne LiDAR data. The response variable of the model is forest stem volume, was measured by random sampling from each individual plot of the 30 circular sample plots collected in Bonghwa-gun, Gyeong sangbuk-do, while the predictor variables for the model are Height Percentiles(HP) and Height Bin(HB), which are metrics extracted from raw LiDAR data. In order to find the most appropriate model, the candidate models are constructed from simple linear regression, quadratic polynomial regression and multiple regression analysis and the cross-validation tests were conducted for verification purposes. As a result, $R^2$ of the multiple regression models of $HB_{5-10}$, $HB_{15-20}$, $HB_{20-25}$, and $HBgt_{25}$ among the estimated models was the highest at 0.509, and the PRESS statistic of the simple linear regression model of $HP_{25}$ was the lowest at 122.352. $HB_{5-10}$, $HB_{15-20}$, $HB_{20-25}$, and $HBgt_{25}-based$ models, thus, are comparatively considered more appropriate for Korean forests with complicated vertical structures.

• Journal of dental hygiene science
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• v.7 no.4
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• pp.295-302
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• 2007

The purpose of this study is to make formulated examination and analysis about major two factors of dental hygienic students' satisfaction at clinical training, i.e. the contents of clinical training and their duties satisfaction, so that it can provide a basic reference material for more efficient clinical training and education. This study conducted a questionnaire survey for 427 students who were taken via simple random sampling from sophomore and junior dental hygienic students, who already experienced in clinical training courses, at some universities(and colleges) in Metropolitan and province areas. The data collected from this survey were analyzed using SPSS WIN 11.5, in parallel with t-test, one-way ANOVA and ${\chi}^2$(Chi-square) test. It was found that our students didn't feel so much satisfied at clinical training(satisfaction level = 3.34). Overall, they didn't show any significant satisfaction with the contents of training and the experiences in clinical training duties. Our dental hygiene students showed relatively low satisfaction with the contents of clinical training as well as satisfaction at clinical training duties, which ie that current clinical training in dental hygienics still remain at the level of simple assistance for dental treatment.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.333-343
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• 2015

This research aims at identifying the goshawk's possible and replaceable breeding ground by using the MaxEnt prediction model which has so far been insufficiently used in Korea, and providing evidence to expand possible protection areas for the goshawk's breeding for the future. The field research identified 10 goshawk's nests, and 23 appearance points confirmed during the 3rd round of environmental research were used for analysis. 4 geomorphic, 3 environmental, 7 distance, and 9 weather factors were used as model variables. The final environmental variables were selected through non-parametric verification between appearance and non-appearance coordinates identified by random sampling. The final predictive model (MaxEnt) was structured using 10 factors related to breeding ground and 7 factors related to appearance area selected by statistics verification. According to the results of the study, the factor that affected breeding point structure model the most was temperature seasonality, followed by distance from mixforest, density-class on the forest map and relief energy. The factor that affected appearance point structure model the most was temperature seasonality, followed by distance from rivers and ponds, distance from agricultural land and gradient. The nature of the goshawk's breeding environment and habit to breed inside forests were reflected in this modeling that targets breeding points. The northern central area which is about $189.5 km^2$(2.55 %) is expected to be suitable breeding ground. Large cities such as Cheongju and Chungju are located in the southern part of Chungcheongbuk-do whereas the northern part of Chungcheongbuk-do has evenly distributed forests and farmlands, which helps goshawks have a scope of influence and food source to breed. Appearance point modeling predicted an area of $3,071 km^2$(41.38 %) showing a wider ranging habitat than that of the breeding point modeling due to some limitations such as limited moving observation and non-consideration of seasonal changes. When targeting the breeding points, a specific predictive area can be deduced but it is difficult to check the points of nests and it is impossible to reflect the goshawk's behavioral area. On the other hand, when targeting appearance points, a wider ranging area can be covered but it is less accurate compared to predictive breeding point since simple movements and constant use status are not reflected. However, with these results, the goshawk's habitat can be predicted with reasonable accuracy. In particular, it is necessary to apply precise predictive breeding area data based on habitat modeling results when enforcing an environmental evaluation or establishing a development plan.

• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.979-995
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• 2023

As wildfires are difficult to predict, real-time monitoring is crucial for a timely response. Geostationary satellite images are very useful for active fire detection because they can monitor a vast area with high temporal resolution (e.g., 2 min). Existing satellite-based active fire detection algorithms detect thermal outliers using threshold values based on the statistical analysis of brightness temperature. However, the difficulty in establishing suitable thresholds for such threshold-based methods hinders their ability to detect fires with low intensity and achieve generalized performance. In light of these challenges, machine learning has emerged as a potential-solution. Until now, relatively simple techniques such as random forest, Vanilla convolutional neural network (CNN), and U-net have been applied for active fire detection. Therefore, this study proposed an active fire detection algorithm using state-of-the-art (SOTA) deep learning techniques using data from the Advanced Himawari Imager and evaluated it over East Asia and Australia. The SOTA model was developed by applying EfficientNet and lion optimizer, and the results were compared with the model using the Vanilla CNN structure. EfficientNet outperformed CNN with F1-scores of 0.88 and 0.83 in East Asia and Australia, respectively. The performance was better after using weighted loss, equal sampling, and image augmentation techniques to fix data imbalance issues compared to before the techniques were used, resulting in F1-scores of 0.92 in East Asia and 0.84 in Australia. It is anticipated that timely responses facilitated by the SOTA deep learning-based approach for active fire detection will effectively mitigate the damage caused by wildfires.

• The korean journal of orthodontics
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• v.33 no.1 s.96
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• pp.41-49
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• 2003

This study examined the relations between degree of posterior dental compensation and skeletal discrepancy in Class III malocclusion. The pretreatment lateral cephalogras and dental casts of 87 skeletal Class III adults were selected to provide a random sampling of skeletal Class III malocclusion. Skeletal discrepancy was described with ANB angle, Wits appraisal, SN-Mn plane angle, FMA and ratios of basal arch width. Degree of posterior dental compensation was described with maxillary intermolar angle, mandibular interolar angle and sum of intermoloar angle. The relationships between skeletal discrepancy and degree of posterior dental compensation were analyzed with simple correlation analysis, stepwise multiple regression analysis. The results were as follows 1. A strong association was found between the variation in the anteroposterior measure, ANB angle and the variation of posterior dental compensation measures, sum of intermolar angle and mandibular intermolar angle in skeletal Class III malocclusion. 2. There was no statistically significant relationship between the variation in the vertical measures and the variation of posterior dental compensation measures in skeletal Class III malocclusion. 3. There was no statistically significant relationship between the variation in the anteroposterior and vortical measures and degree of basal arch width discrepancy.

• Journal of Korean society of Dental Hygiene
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• v.4 no.2
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• pp.193-207
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• 2004

The aims of the study are as following : First, define and clarify the role and function of the dental hygienist. Second, based on thai definition, present an improved dental hygienist curriculum, improving their special competence. This study seeks to present a way for promoting role of dental hygienists as independent specialists, rather than as auxiliaries, contributing to better dental service in the process. The research was pursued by surveying by questionnaire those directly related to dental hygiene. They are 58 professors of dental hygiene, 164 dentists, 253 dental hygienists and 496 dental hygiene students, selected by the method of simple random sampling. Due to the small size of the sample, professors' group was analysed only through frequency and probabilities. For groups with larger samples(dentists, dental hygienists, dental hygiene students), methods of chi square(${\chi}^2$) tests, frequency analysis and one-way ANOVA were used in their analysis. Conclusions of the study are as following : First, role and function of the dental hygienist was defined and clarified. According to the analysis of the survey, main role of the dental hygienists as perceived by 62.9% of dentists was supporting treatments and managing patients and facility. This perception by dentists differs significantly to perception of other groups, which saw main role of dental hygienists as preventive dental treatment and dental hygiene education. Also, only 20.2% of dental hygienists perceived patients and facility management as their main role. This divergence of perception between groups weakens speciality competence of dental hygienists. To strengthen dental hygienists' speciality competence, preventive dental treatment and dental hygiene education must be defined as main role of dental hygienists. Furthermore, role of dental hygienists can be categorized into cooperative and auxiliary role. Second, in order to strengthen speciality competence of dental hygienists, their education must be augmented with curriculum emphasizing cooperative role. Specifically, courses on preventive dental treatment, dental hygiene education and dental X-ray photography must become compulsory, as well as becoming more comprehensive and organized. Also, training in schools and hospitals must be focused on those subjects. In addition, courses concerning auxiliary role must be incorporated into optional courses and more pedagogical courses are needed to widen students' career choices. Third, practical relevance of national dental hygienist certification examination must be heightened. In the survey, all groups gave negative response to questions concerning practical relevance of national dental hygienist certification test. Specifically, contents of the tests must be changed to test participants' competence in the cooperative area. Also, the test itself must be strengthened by adding practical examination to the certification scheme, as well as having more difficult examinations.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.12 no.1
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• pp.79-110
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• 2001

Tourist Destination is based on tourism attractions. Components of Tourism attraction are included tourism resources, entertainment facilities, transportation, accommodation, infrastructure, assistance facilities & service, hospitality, information facilities & service, and retailing & service. Tourism resources of them is the key to determine destination development pattern, because tourism attraction that attract tourists is based on tourism resources. Therefore, there are need to study what is tourism attraction of destination at the view of tourists and what is destination development pattern based on it to develop tourism attraction that is able appeal tourists. The purpose of this study is to examine what effect of tourism attraction affects destination development pattern. This study defined Haeundae, Kwanganri, Songjung, Taejongdae in Pusan, Korea as research areas. Research data were collected from 300 respondents by a simple random sampling method. A final 284 usable questionaries were used for empirical analysis after data purification process. Reliability and validity of the scale on the tourism attraction, destination image, and facility needs have been evaluated using Cronbach $\alpha$, item-total correlations. This study analyzed the factors of the tourism attraction and destination images. The result obtained that tourism attraction is divided relaxation attraction, local activity attraction, culture . nature attraction and touring circuit attraction, and destination image is divided culture . urban attractiveness, touring attractiveness, local . stay attractiveness, convenience of travel and relativeness for destination investigated. ANOVA and regression (stepwise) were used to test hypotheses. Based on the results of hypotheses testing, major findings of the empirical research are as follow : 1. The tourism attraction and destination image are significantly different, but facility needs are not significantly by destinations (e. g. Haeundae, Kwanganri, Songjung, Taejongdae) . 2. Destination development pattern is a(fact by the tourism attraction in partial. In case of Haeundea, relaxation attraction take effect partially spa, history and marine/spa tourism. 3. The destination development pattern is influenced by the destination image in partial. In case of Kwanganri, the natural . activity attractiveness and urban tourism images have been found as influential factors that affect marine tourism. 4. The destination images are influenced the physical attributes in literature review, but the destination image are taken effect partially the tourism attraction in this study. 5. Destination development pattern are influenced by the tourism attraction and the destination image partially. This research has provided a variety of practical suggestions. Especially, it was suggested that the destination have appeal to tourists by strengthening attraction and improving weakness. Also, we need to specialize destination in same destination development pattern.