• Journal of Korean Society of Forest Science
• /
• v.100 no.1
• /
• pp.42-51
• /
• 2011

This study was conducted to analyze correlation of above- and below-ground biomass and to drive regression equation suitable for estimating standing tree biomass between natural and planted stands of Pinus densiflora for. erecta of one age-class in Gangwon province, Republic of Korea. Total 40 trees, 10 from the naturally regenerated and 10 from the planted stands in each of two studied sites, were uprooted to measure height, diameter at root color (DRC), and the dry weights of stem, branches, and needles. The length, weight, and volume of the main and horizontal roots were also measured. Most of the above-ground traits except height were highly correlated with most of the other above-ground traits and the below-ground traits except the length of roots (p < 0.05). Especially, the DRC, which is measured easily on the standing tree, was highly correlated with most of the traits in all studied stands (p < 0.01). Thus, the DRC would be the most desirable trait to estimate not only above-ground biomass but also below-ground biomass. However, height was not a good variable to estimate standing tree biomass of Pinus densiflora for. erecta of one age-class in Gangwon province because it was not correlated with most of other traits. Regression equations derived from the current study could be used effectively as a basic data for estimating above-ground and below-ground biomass using DRC.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.49 no.3
• /
• pp.15-26
• /
• 2012

Recently, due to applicability increase of vector data based digital map for geographic information and evolution of geographic measurement techniques, large volumed GIS(geographic information service) services having high resolution and large volumed data are flowing actively. This paper proposed an efficient vector map compression technique using the SEC(spatial energy compaction) based on classified bins for the vector map having 1cm detail and hugh range. We encoded polygon and polyline that are the main objects to express geographic information in the vector map. First, we classified 3 types of bins and allocated the number of bits for each bin using adjacencies among the objects. and then about each classified bin, energy compaction and or pre-defined VLC(variable length coding) were performed according to characteristics of classified bins. Finally, for same target map, while a vector simplification algorithm had about 13%, compression ratio in 1m resolution we confirmed our method having more than 80% encoding efficiencies about original vector map in the 1cm resolution. Also it has not only higher compression ratio but also faster computing speed than present SEC based compression algorithm through experimental results. Moreover, our algorithm presented much more high performances about accuracy and computing power than vector approximation algorithm on same data volume sizes.

• The Journal of Industrial Distribution & Business
• /
• v.9 no.5
• /
• pp.93-104
• /
• 2018

Purpose - This study is to investigate the relationship among emotional intelligence, self-efficacy and job stress of foreign life insurance consultants focusing on the mediating effect of self-efficacy. Regarding job security, in general foreign life insurance companies in Korea have more severe working conditions in terms of required contract performance. For foreign life insurance consultants, they are assumed to need higher level of emotional intelligence and self efficacy to meet the conditions. In this study, focus is cast on these aspects. Research design, data, and methodology - Basically the research is conducted upon questionnaires responded by foreign life insurance consultants. That is, data are collected from 255 sample of insurance consultants who work for a foreign owned life insurance company. The Questionnaire measure the level of emotional intelligence, self-efficacy and job stress of insurance consultants. The data are analyzed using pearson's correlation coefficient and hierarchical multiple regression, descriptive statistics, t-test, ANOVA, Durbin-Watson test. Results - The general characteristics of respondents are gender, age, marital status, education level, income monthly, career length, change jobs no, working day per week, call no. per week, meeting no. with client per week, contract regularity, contract no. per month and cancellation contract per year. The mean of emotional intelligence is 2.63, self-efficacy is 3.44 and job stress is 2.20. Emotional intelligence is composed with mean value of self emotion appraisal(3.93), other's emotion appraisal(3.78), regulation of emotion(3.29) and use of emotion(3.52). The mean of self efficacy is composed with mean value of self-confidence(3.41), self-regulated efficacy(3.59) and preference task difficulty(3.30). The job stress is composed with mean value of job requirement(2.61), lack of job autonomy(1.99), conflict of personal relations(1.99), job instability(2.38), organizational system(2.19) and inappropriate compensation(2.07). There is a significant positive correlation between emotional intelligence and self-efficacy. The emotional intelligence and self-efficacy are significantly negative correlation with job stress. The self-efficacy is showed a mediating variable between emotional intelligence and job stress. Conclusions - To decrease job stress level, foreign life insurance company should find the factors to improve the emotional intelligence and self-efficacy of life insurance consultants, and develop appropriate plans using a mediating role of self- efficacy between emotional intelligence and job stress.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.48 no.5
• /
• pp.107-116
• /
• 2011

In this paper, a traffic adaptive sleep based medium access control (TAS-MAC) protocol for wireless sensor networks (WSNs) is proposed. The protocol aims for WSNs which consist of clustered sensor nodes and is based on TDMA-like schema. It is a typical schedule based mechanism which is adopted in previous protocols such as LEACH and Bit-Map Assisted MAC. The proposed MAC, however, considers unexpected long silent period in which sensor nodes have no data input and events do not happen in monitoring environment. With the simple traffic measurement, the TAS-MAC eliminates scheduling phases consuming energy in previous centralized approaches. A frame structure of the protocol includes three periods, investigation (I), transmission (T), and sleep-period (S). Through the I-period, TAS-MAC aggregates current traffic information from each end node and dynamically decide the length of sleep period to avoid energy waste in long silent period. In spite of the energy efficiency of this approach, the delay of data might increase. Thus, we propose an advanced version of TAS-MAC as well, each node in cluster sends one or more data packets to cluster head during the T-period of a frame. Through simulation, the performance in terms of energy consumption and transmission delay is evaluated. By comparing to BMA-MAC, the results indicate the proposed protocol is more energy efficient with tolerable expense in latency, especially in variable traffic situation.

• Journal of Periodontal and Implant Science
• /
• v.35 no.2
• /
• pp.359-369
• /
• 2005

It has been suggested that morphologic characteristics of the periodontium are partly related to the shape and form of the teeth. Furthermore, the severity of symptoms of periodontal disease have been proposed to differ among these various morphologic entities or "biotypes". The purpose of the present study was to examine the relationship between the form of the crowns in the maxillary anterior tooth segment and (1) a group of morphological characteristics and (2) the thickness of the gingiva. The thickness of gingiva was measured by ultrasonic device(SDM). 100 subjects devoid of symptoms of destructive periodontal disease were examined regarding, e.g., probing depth, gingival recession, width of keratinized gingiva, thickness of the keratinized gingiva. From maxillary study cast, the width(at the apical third-CW) and the length(CL) of the crowns of the 6 anterior teeth were determined. A CW/CL-ratio was calculated for each tooth and averaged for each tooth region. The individual mean CW/CL-ratio values for the central incisors were ranked. The 10 subjects ranked highest and the 10 ranked lowest were selected as having either a long-narrow(group N) or a short-wide(group W) form of the crown of the tooth. The data for each of the examined parameters were averaged for each tooth region in each subject and mean values for subjects in groups W and N were compared using the Student t-test. Stepwise multiple regression analysis, including data from the whole sample, was performed for each tooth region with the thickness of the free gingiva as the dependent variable. The results from the analyses demonstrated that individuals with a long-narrow form of the central incisors displayed, compared to individuals with a short-wide crown, form (l) a narrow zone of keratinized gingiva, (2) a pronounced "scalloped" contour of the gingival margin. There was no significant difference between groups N and W with respect to the thickness of the keratinized gingiva. The CW/CL-ratio data revealed that a certain form of the crowns in the central incisors was accompanied by a similar form in the lateral incisors and canine tooth region. The regression analyses demonstrated that the thickness of the keratinized gingiva in central, lateral incisors and canines was significantly related to the width of the keratinized gingiva.

• Health Policy and Management
• /
• v.34 no.1
• /
• pp.78-86
• /
• 2024

Background: The purpose of this study was to determine the effectiveness of the specialty hospital system by comparing the medical use of inpatients who had artificial joint replacement surgery in specialty hospitals and non-specialty hospitals. Methods: This study utilized 2021-2022 healthcare benefit claims data provided by the Health Insurance Review and Assessment Service. The dependent variable is inpatient medical use which is measured in terms of charges per case and length of stay. The independent variable was whether the hospital was designated as a specialty hospital, and the control variables were patient-level variables (age, gender, insurer type, surgery type, and Charlson comorbidity index) and medical institution-level variables (establishment type, classification, location, number of orthopedic surgeons, and number of nurses). Results: The results of the multiple regression analysis between charges per case and whether a hospital is designated as a specialty hospital showed a statistically significant negative relationship between charges per case and whether a hospital is designated as a specialty hospital. This suggests a significant low in charges per case when a hospital is designated as a specialty hospital compared to a non-specialty hospital, indicating that there is a difference in medical use outcomes between specialty hospitals and non-specialty hospitals inpatients. Conclusion: The practical implications of this study are as follows. First, the criteria for designating specialty hospitals should be alleviated. In our study, the results show that specialty hospitals have significantly lower per-case costs than non-specialty hospitals. Despite the cost-effectiveness of specialty hospitals, the high barriers to be designated for specialty hospitals have gathered the specialty hospitals in metropolitan and major cities. To address the regional imbalance of specialty hospitals, it is believed that ease the criteria for designating specialty hospitals in non-metropolitan areas, such as introducing "semi-specialty hospitals (tentative name)," will lead to a reduction in health disparities between regions and reduce medical costs. Second, it is necessary to determine the appropriateness of the size of hospitals' medical staff. The study found that the number of orthopedic surgeons and nurses varied in charges per case. Therefore, it is believed that appropriately allocating hospital medical staff can maximize the cost-effectiveness of medical services and ultimately reduce medical costs.

• Journal of the Korean Society of School Health
• /
• v.1 no.2
• /
• pp.34-49
• /
• 1988

The purpose of this study is to identify the status of school health and analyze affecting factors of school nurses' self confidence and nursing activities of the secondary school in Seoul. The data was collected from 13th of August to 30th of October. The self reported questionairs were distributed during one of the school nurses seminars held in Seoul and 93 secondary school nurses answered. Analysis of the data was done utilizing SPSS for percentage, mean, T-test ANOVA and Pearson Correlation Coefficients. The results of study are summerized as follows; 1. General Characteristics The mean age of the subjects was 33.4 and mean length of experience as a school nurse was 7.3 years. 79.5 percent of them had clinical experiences and the mean clinic experience was 2.1 years. The majority of them were graduate of the baccalaureate nursing programs and 82.8 percent of them were married. 72.0 percent of the sample had religion, and 60.2 percent of them were in the national or public schools. 90.3 percent of them had independent duty. 2. The status of school health resources In average, there were 2,445 students, 37 classes and 63 teachers per school nurse. 48.4 percent of them were aware of the school budget. The budget for school health was 585,000 won per school in average. 30.0 percent of the schools had school health organization. The schools whose health clinics were on the first floor consisted of 79.3 percent, among them 42.9 percent were on the center of the building office. 3. Activities of school health nursing The average number of students using health clinic were 430 per month. The majority of the problem was digestive problem. There were 7.5 times of mean correspondences with parents per year. The activities of the school nurses were clinic management (29.0%), health care services (23.5%) and health education (14.1%). 4. The degrees of self confidence of the school nurse and nursing activities Self confidence measured by 6 items of self-reported questionaires scored by 4 point Likert Scale revealed. The nurses' self-confidence was 2.922 in clinic management, 2.909 in health education, 2.759 in program planning and evaluation, 2.757 in health care services, 2.692 in management of school environment, and 2.250 in operation of school health organization. The nursing activities scored by 2 point. The nursing activities was 1,870 in program planning and evaluation, 1.853 in health education, 1.843 in clinic management, 1.739 in health care services, 1.696 in management of school environment and 1.265 in operating of school health organization. 5. Factors affecting self confidence and nursing activities of school nurses The general characteristics of the school nurses and the school health resources were related to self confidence and nursing activities. The most significant variable to nurses' self confidence was type of the school ownership and the presence of school health organization was the most significant factor to nursing activities.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.4 no.4
• /
• pp.12-20
• /
• 2001

The temporal variability in near-field mixing characteristics of discharging plumes in oceanic environment was investigated using the time series data of the buoyant jet parameters. Based on the currents and density profiles observed in Masan outfall site and effluent discharge flowrates for 63days of summer season, the temporal variabilities and those occurrence frequency were obtained by line plume equations. The results show that wide range of variability in Masan outfall's mixing characteristics was found due to the temporal changes of effluent flowrates and ambient oceanic conditions. The near-field dilution was in the range of 30~71 with the averaged dilution of 34, which was a good agreement with field measurements of salinity deficit. The length of mixing zone was in the range of 5.4~36.2 m with the average of 9.5 m, and the plume rise height was in the range of 8.1~10.2 m with the average of 8.9 m. However, only the 30~44% of the whole results are higher than the averages, which indicates the necessity of this frequency analysis with the continuously measured data for designing and managing the ocean outfall system.

• Journal of Korean Society of Transportation
• /
• v.35 no.5
• /
• pp.423-433
• /
• 2017

During recent 5 years, it was recorded that 20% of total accident frequency and 30% of total number of death have been occurred due to drowsy driving. Drowsy driving accident is result from the loss of driving ability due to driver's accumulated fatigue. Continuous driving time can be measured as a surrogate variable to quantify the level of fatigue. The main purpose of this research is to investigate statistical correlation between the proportion of continuous driving vehicle (more than 2 hours) and the number of drowsy accidents. To carry this out, continuous driving time was measured using GPS route-guidance trajectory data. Also, accident frequency, traffic volume and segment length were collected to estimate safety performance function (SPF) for Jungbunearuk expressway in Korea. Through various types of estimated SPFs, statistical correlation was analyzed based on estimated statistical indices. This research can provide theoretical background for enforcement to regulate commercial vehicle driver's continuous driving time. In addition, throughout the trajectory data expansion, it is expected that strategy for anti-drowsy driving facilities installation can be established based on the suggested methodology.

• Journal of Cadastre & Land InformatiX
• /
• v.49 no.2
• /
• pp.135-149
• /
• 2019

This article analyzed economic effects of changes in spatial accessibility on regional touruism expenditure structure resulting from highway investments on Gangwon province, Korea. The Seemingly Unrelated Regress(SUR) model is applied to analyze the structure of change in tourism expenditure of Gangwon Province, and the competition and complementary relationship of tourist demand were analyzed among 18 counties in Gangwon by Dendrinos-Sonis method. The spatial accessibility has a significant effect on the increase in amount of tourist expenditure, but by 1% increase in the accessibility resulted in a reduction of length of stay -0.18% and travel costs -0.34% by respectively. The most powerful variable for improving the on-site economy is the tourist service establishment, which increases one unit, the amount of tourist expenditure increased by 3.6%. Moreover, the competition and supplemental relationship of tourism demands in Gangwon was decided by the conditions under which traffic flow with passing occurred, such as inland or ocean-typed travel attractions, adjacent or remote regions to the highway. The limitations of this study were not able to use raw data of tourism expenditures before and after the opening the highway due to the restriction of priority data, and further research on the appropriate level of spatial accessibility for the regional economy is needed.