• 제목/요약/키워드: 지역 최소점

Search Result 196, Processing Time 0.023 seconds

A Study on Radiation Safety Management by Dental Hygienist (치과위생사의 방사선 안전관리에 대한 조사 연구)

  • Kang, Eun-Ju;Lee, Kyung-Hee;Kim, Young-Im
    • Journal of dental hygiene science
    • /
    • v.5 no.3
    • /
    • pp.105-112
    • /
    • 2005
  • In spite of relatively low level of radiation dose used at dental clinics, long term exposure may be harmful, so radiation workers at dental clinics must be well aware of its danger. This study was to analyze the factors to have an influence on safety management behavior in the radiography chamber by understanding the relationship among the knowledge, attitudes and behavior in regard with radiation safety management by dental hygienists in order to take preventive measures for dental hygienists and suggest ideas to develop radiation safety training programs. For this, we contacted dental hygienists working at the local dental clinics for 4 months from December of 2003 to march of 2004 and obtained the following findings. 1. Concering the knowledge level of radiation safety management, $8.59{\pm}2.36$ was average score with the highest of 13 and the lowest of 3 from 15-scale test. In addition, knowledge level of radiation safety management by general characteristics showed statistically significant difference according to working experience (p < 0.001), marital status (p < 0.001), attendance rate of radiation safety management training program (p < 0.001), and type of clinic (p < 0.001). 2. Concering the attitude level of radiation safety management, $4.08{\pm}0.50$ is average score with the highest of $4.31{\pm}0.73$ and the lowest of $3.82{\pm}0.89$ by item from 5-scale test. Besides, attitude level of radiation safety management by general characteristics showed statistically significant difference according to age (p < 0.001), working experience (p < 0.05), attendance rate of radiation safety management training program (p < 0.01), and type of clinic (p < 0.001). 3. Concering the behavior level of radiation safety management, $2.89{\pm}0.77$ is average score from 5-scale test, which was relatively low in comparison with the level of attitude and the highest score was $3.82{\pm}0.94$ and the lowest $2.37{\pm}1.04$ by item. Behavior level of radiation safety management by general characteristics showed statistically significant difference according to working experience (p < 0.001) and type of clinic (p < 0.001). 4. From the survey of relationship among knowledge, attitude and behavior of radiation safety management was, we found that the higher the knowledge level of radiation safety management, the higher the level of attitude and behavior, and the higher the attitude level was, the higher the level of behavior.

  • PDF

An Analysis of Accessibility to Hydrogen Charging Stations in Seoul Based on Location-Allocation Models (입지배분모형 기반의 서울시 수소충전소 접근성 분석)

  • Sang-Gyoon Kim;Jong-Seok Won;Yong-Beom Pyeon;Min-Kyung Cho
    • Journal of the Society of Disaster Information
    • /
    • v.20 no.2
    • /
    • pp.339-350
    • /
    • 2024
  • Purpose: This study analyzes accessibility of 10 hydrogen charging stations in Seoul and identifies areas that were difficult to access. The purpose is to re-analyze accessibility by adding a new location in terms of equity and safety of location placement, and then draw implications by comparing the improvement effects. Method: By applying the location-allocation model and the service area model based on network analysis of the ArcGIS program, areas with weak access were identified. The location selection method applied the 'Minimize Facilities' method in consideration of the need for rapid arrival to insufficient hydrogen charging stations. The limit distance for arrival within a specific time was analyzed by applying the average vehicle traffic speed(23.1km/h, Seoul Open Data Square) in 2022 to three categories: 3,850m(10minutes), 5,775m(15minutes), 7,700m(20minutes). In order to minimize conflicts over the installation of hydrogen charging stations, special standards of the Ministry of Trade, Industry and Energy applied to derive candidate sites for additional installation of hydrogen charging stations among existing gas stations and LPG/CNG charging stations. Result: As a result of the analysis, it was confirmed that accessibility was significantly improved by installing 5 new hydrogen charging stations at relatively safe gas stations and LPG/CNG charging stations in areas where access to the existing 10 hydrogen charging stations is weak within 20 minutes. Nevertheless, it was found that there are still areas where access remains difficult. Conclusion: The location allocation model is used to identify areas where access to hydrogen charging stations is difficult and prioritize installation, decision-making to select locations for hydrogen charging stations based on scientific evidence can be supported.

Estimation of Daily Maximum/Minimum Temperature Distribution over the Korean Peninsula by Using Spatial Statistical Technique (공간통계기법을 이용한 전국 일 최고/최저기온 공간변이의 추정)

  • 신만용;윤일진;서애숙
    • Korean Journal of Remote Sensing
    • /
    • v.15 no.1
    • /
    • pp.9-20
    • /
    • 1999
  • The use of climatic information is essential in the industial society. More specialized weather servies are required to perform better industrial acivities including agriculture. Especially, crop models require daily weather data of crop growing area or cropping zones, where routine weather observations are rare. Estimates of the spatial distribution of daily climates might complement the low density of standard weather observation stations. This study was conducted to estimate the spatial distribution of daily minimum and maximum temperatures in Korean Peninsula. A topoclimatological technique was first applied to produce reasonable estimates of monthly climatic normals based on 1km $\times$ 1km grid cell over study area. Harmonic analysis method was then adopted to convert the monthly climatic normals into daily climatic normals. The daily temperatures for each grid cell were derived from a spatial interpolation procedure based on inverse-distance weighting of the observed deviation from the climatic normals at the nearest 4 standard weather stations. Data collected from more than 300 automatic weather systems were then used to validate the final estimates on several dates in 1997. Final step to confirm accuracy of the estimated temperature fields was comparing the distribution pattern with the brightness temperature fields derived from NOAA/AVHRR. Results show that differences between the estimated and the observed temperatures at 20 randomly selected automatic weather systems(AWS) range from -3.$0^{\circ}C$ to + 2.5$^{\circ}C$ in daily maximum, and from -1.8$^{\circ}C$ to + 2.2$^{\circ}C$ in daily minimum temperature. The estimation errors, RMSE, calculated from the data collected at about 300 AWS range from $1.5^{\circ}C$ to 2.5$^{\circ}C$ for daily maximum/minimum temperatures.

Trend Analysis of Medical Care Utilization among People with Autistic Spectrum Disorder Using National Health Insurance Data (자폐성장애인의 의료이용 경향분석 및 시사점 : 국민건강보험자료를 이용한 융복합적 접근)

  • Yun, Jieun;Kim, Hyun Joo
    • Journal of Digital Convergence
    • /
    • v.16 no.11
    • /
    • pp.411-418
    • /
    • 2018
  • The purpose of this study was to estimate the current status and trends of healthcare utilization among people with ASD. Using National Health Insurance open database, from 2010 to 2017. We analyzed the treatment prevalence for people with ASD, the pattern of healthcare utilization, the difference in medical care utilization according to age, and the type and location of main medical institutions. The main results of the study are as follows: First, the medical utilization has been continuously increasing from 2010 to 2017. The total amount of medical utilization is increased by 50% in 2017 compared to 2010, and the treatment prevalence was estimated to be 79.1% in 2017 and medical uses for the next three years is also increasing. Second, the pattern of medical care utilization varied widely according to age, especially after 20 years of age. Third, the types of medical institutions that were mainly used were 45.6% in the medical clinic and 35.9% in Seoul. The results of this study can be used as a minimum reference point of evaluating the effectiveness of government policy on future autistic disorders. However, further studies are required to increase the prevalence of treatment for autistic patients and to find out the difference in medical use according to age.

A Relationship Between Dentistry Consumers' Knowledge and Expectation of Dental Implants (치과의료소비자의 임플란트에 대한 지식과 기대도의 관련성)

  • Yoo, Eun-Mi;Shim, Hyun-ju
    • Journal of dental hygiene science
    • /
    • v.10 no.4
    • /
    • pp.219-225
    • /
    • 2010
  • The purpose of this study was to examine the patients' knowledge and expectation of dental implants and to provide effective consulting and accurate information on implants to them. To that end, between March 23, 2008 and June 5, 2008, patients who were visiting dental clinics (hospitals) in Seoul, Gyeonggi-do, and Incheon areas were surveyed. 84.7% of subjects said that they recognized implants, and the largest number of them (26.7%) of subjects came to know via friends. According to an analysis of subjects' knowledge of the dental implant operation, the maximum value was 4.06, and the minimum value was 3.05. The opinion value on the need to have regular examination after the implant operation was highest at 4.06. Regarding expectation over the implant operation, the maximum value was 4.42, and the minimum value was 1.78. The opinion value on considering the implant operation capability the most important was the highest at 4.42. The relationship between the knowledge of and expectation over implants was significant. By gender, females had a significantly higher level of knowledge than males. Regarding preference, females scored 3.27 points, and males scored 3.23 points. By occupation, professionals earned the highest score of 3.55 in knowledge, and professionals earned the highest score of 3.31 in expectation. According to an analysis of the relation between variables of knowledge of and variables of expectation over implants, the correlation coefficient (r) between the two factors was 0.362, indicating a positive relevancy(+)(p<.01).

Type and Characteristics of Debris Landform in Mt. Mudeung (무등산 암설지형의 유형과 특징)

  • Oh, Jong-Joo;Park, Seoung-Phill;Seong, Yeong-Bae
    • Journal of the Korean association of regional geographers
    • /
    • v.18 no.3
    • /
    • pp.253-267
    • /
    • 2012
  • The study looked into the type and characteristics of debris landforms in Mt. Mudeung. By focusing on the representative area, we aimed to categorize the debris landforms based on the morphologic and genetic characteristcis. The types of debris areas in Mt. Mudeung can be divided into the exposed debris type, mixed type of matrix, and the boulder-hidden type. Supply of block in the debris slope area displays different features depending on types of rocks. For the stony slopes of andesite, the block must be moved from the columnar joint or cliff in the upper part. The andesite debris slopes display dominant edge shape while displaying no round shape. The granite stony slopes display dominant round shape and the present exposed slope was assumed to be formed as the core stone which was deep weathered moved along slope during the periglacial era and the matrix was removed after post-glacial era. The movements of blocks are assumed to be caused by solifluction process. The joint area where granite and andesite areas meet, granite is located beneath andesite area, and this implies that blocks were actively freezing and creeping by solifluction and freezing and thawing at that time. It can be assumes that the granite matrix formed plain slope and then andesite boulder covered up the slope. Currently, the blocks in the stony slopes of Mt. Mudeung shows almost no mobility and the stony slopes created under periglacial climate can be considered to be fossil landform.

  • PDF

Study on the Induced Interaction between Groundwater and Surface Water due to the Tunnel Construction (터널 건설에 따른 인근 하천 영향 평가를 위한 연구)

  • 김태희;김영식;하규철;김구영;고동찬;양인제;홍순택
    • The Journal of Engineering Geology
    • /
    • v.14 no.1
    • /
    • pp.81-91
    • /
    • 2004
  • The objective of this study is the evaluation of the tunneling effect on the goundwater-surface water interaction. The designed tunnel line is laid beneath the Hapo-cheon, which runs throughout the study area. And, the pre-evaluation of the tunnel-influence on the Gapo-cheon is urgently needed. However, it is very difficult to find out the similar domestic and/or foreign cases. In this study, the numerical modeling technique was not considered because of the insufficient data. Instead of the numerical modeling, the measurement and analysis of the stream flow rates 5 different points were adopted to evaluate the influence of the tunnel construction on the Gapo-cheon. Based on the analysis of flow monitoring data, it can be concluded that 39% of flow rate in Gapo-cheon is contributed by the groundwater discharge, as baseflow and the construction of tunnel can seriously decrease the flow rate in Gapo-cheon.

Collaborative Stepwise Movement of Mobile Sensor Nodes for Energy Efficient Dynamic Sensor Network Coverage Maintenance (모바일 센서노드들의 협동형 단계적 이동기법 기반의 에너지 효율적인 동적 센서네트워크 커버리지 관리)

  • Han, Ngoc-Soc;Kim, Seong-Whan
    • The KIPS Transactions:PartC
    • /
    • v.16C no.4
    • /
    • pp.535-542
    • /
    • 2009
  • Wireless Sensor Network (WSN) is a wireless network consisting of spatially distributed autonomous devices, using sensors to cooperatively monitor physical or environmental conditions. WSNs face the critical challenge of sustaining long-term operation on limited battery energy. Coverage maintenance has been proposed as a promising approach to prolong network lifetime. Mobile sensors equipped with communication devices can be leveraged to overcome the coverage problem. In this paper, we propose a stepwise movement scheme using perimeter coverage property for the coverage maintenance problem. In our scheme, each sensor monitors neighboring dead nodes, determines vulnerable node (i.e. dead node which makes uncovered area), computes the center of uncovered area HC, and makes a coordinated stepwise movement to compensate the uncovered area. In our experimental results, our scheme shows at least 50 % decrease in the total moving distance which determines the energy efficiency of mobile sensor.

Implementing the Urban Effect in an Interpolation Scheme for Monthly Normals of Daily Minimum Temperature (도시효과를 고려한 일 최저기온의 월별 평년값 분포 추정)

  • 최재연;윤진일
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.4 no.4
    • /
    • pp.203-212
    • /
    • 2002
  • This study was conducted to remove the urban heat island effects embedded in the interpolated surfaces of daily minimum temperature in the Korean Peninsula. Fifty six standard weather stations are usually used to generate the gridded temperature surface in South Korea. Since most of the weather stations are located in heavily populated and urbanized areas, the observed minimum temperature data are contaminated with the so-called urban heat island effect. Without an appropriate correction, temperature estimates over rural area or forests might deviate significantly from the actual values. We simulated the spatial pattern of population distribution within any single population reporting district (city or country) by allocating the reported population to the "urban" pixels of a land cover map with a 30 by 30 m spacing. By using this "digital population model" (DPM), we can simulate the horizontal diffusion of urban effect, which is not possible with the spatially discontinuous nature of the population statistics fer each city or county. The temperature estimation error from the existing interpolation scheme, which considers both the distance and the altitude effects, was regressed to the DPMs smoothed at 5 different scales, i.e., the radial extent of 0.5, 1.5, 2.5, 3.5 and 5.0 km. Optimum regression models were used in conjunction with the distance-altitude interpolation to predict monthly normals of daily minimum temperature in South Korea far 1971-2000 period. Cross validation showed around 50% reduction in terms of RMSE and MAE over all months compared with those by the conventional method.conventional method.

Preventing Subway Crimes : Focusing on Sexual Offenses in the Seoul Metropolitan Subway (지하철범죄 예방전략 : 서울 지하철의 성범죄를 중심으로)

  • Roh, Sung-Hoon;Kim, Hak-Kyong
    • The Journal of the Korea Contents Association
    • /
    • v.12 no.3
    • /
    • pp.190-205
    • /
    • 2012
  • The purpose of the paper is to provide policy suggestions for effectively tackling subway crimes, based on the UK and USA's crime control strategies and systems of subway crimes. The paper attempts to analyze the characteristics of subway crimes in Seoul Subways, and discovers that many of the crimes on the subways are basically 'opportunistic' crimes. In particular, crime statistics of Seoul Subways clearly show that sexual-related crimes are on the sharp increase. In this context, it is of great essence that official vigilance functions should be strengthened in order to eliminate crime opportunities in Seoul Subways. Based on such an analysis - in particular, focusing on official surveillance and response capabilities of subway passengers - the paper finally presents policy recommendations as follows: 1) an increase in the number of police officers of the Subway Police Squad, 2) an increase in the number of CCTV cameras and their effective use, 3) the development of subway riders' defence abilities, 4) strong law enforcement against minor disorder offences based on zero-tolerance policing, and 5) the reinforcement of community partnerships.