• Title/Summary/Keyword: urban effect

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Factors Affecting the Morbidity Related to Respiratory Dieseases in Urban Korea (한국 도시의 만성호흡기 질환 이환율에 영향을 주는 요인)

  • Han, Sung-Hyun;Park, Jae-Sung;Seo, Seung-Hee;Yoon, Jee-Eun;Jee, Sun-Ha
    • Korea journal of population studies
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    • v.28 no.2
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    • pp.205-217
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    • 2005
  • Purpose: To evaluate the factors affecting hospital utilization for respiratory diseases by ecological study design and GIS tool. To raise the social concern for respiratory disease by the result. Methods: Hospital admission data supported by national health insurance cooperation were transformed to spread sheet data format and combined with air monitoring dataset. Air pollution data were collected from the annual report of air monitoring published by Korea Ministry of Environment. Socioeconomic statistics including population density, age distribution, forest ratio etc.. were filed using Korea National Statistical Office database. Multiple linear regression analysis was performed to evaluate the factors affecting hospital utilization for respiratory diseases. Analytical unit was 52 cities. Results: The factors affecting hospital utilization for respiratory diseases were the proportion of population 60 years and over, seaside city, $O_3$ level, smoking rate. Conclusions: However, outdoor pollutants monitoring data and smoking rate have weakness in reflecting individual exposure. Further research is required to propose more illustrative means to evaluate causal relationship between air pollution and respiratory health effect factors.

Interpretation on the subsurface velocity structure by seismic refraction survey in tunnel and slope (탄성파 굴절법 탐사를 이용한 지반 속도분포 해석-터널 및 절토 사면에의 적용 사례)

  • You Youngjune;Cho Chang Soo;Park Yong Soo;Yoo In Kol
    • 한국지구물리탐사학회:학술대회논문집
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    • 1999.08a
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    • pp.48-64
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    • 1999
  • For quantitative evaluation of geotechnical engineering properties such as rippability and diggability, clear interpretation on the subsurface velocity structures should be preceded by figuring out top soil, weathered and soft rock layers, shape of basement, fracture zones, geologic boundary and etc. from the seismic refraction data. It is very important to set up suitable field parameters, which are the configuration of profile and its length, spacings of geophones and sources and topographic conditions, for increasing field data quality Geophone spacing of 3 to 5m is recommended in the land slope area for house land development and 5 to 10m in the tunnel site. In refraction tomography technique, the number of source points should be more than a half of available channel number of instrument, which can make topographic effect ignorable. Compared with core logging data, it is shown that the velocity range of the soil is less than 700m/s, weathered rock 700${\~}$1,200m/s, soft rock 1,200${\~}$1,800m/s. And the upper limit of P-wave velocity for rippability is estimated 1,200 to 1,800m/s in land slope area of gneiss. In case of tunnel site, it is recommended in tunnel design and construction to consider that tunnel is in contact with soft rock layer where three lineaments intersecting each other are recognized from the results of the other survey.

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Three-dimensional Imaging of Subsurface Structures by Resistivity Tomography (전기비저항 토모그래피에 의한 지하구조의 3차원 영상화)

  • Yi Myeong-Jong;Kim Jung-Ho;Chung Seung-Hwan;Suh Jung Hee
    • Geophysics and Geophysical Exploration
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    • v.5 no.4
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    • pp.236-249
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    • 2002
  • We have extended the three-dimensional (3-D) resistivity imaging algorithm to cover the 3-D resistivity tomography problem, where resistivity data are acquired using electrodes installed in several boreholes as well as at the earth surface. The imaging algorithm consists of the 3-D finite element forward modeling and least-squares inversion scheme, where the ACB (Active Constraint Balancing) is adopted to enhance the resolving power of the inversion. Sensitivity analysis with numerical verifications shows that 3-D resistivity tomography is a very appealing method and can be used to get 3-D attitude of subsurface structures with very high-resolution. Moreover, we could accurately handle the topography effect, which could cause artifacts in the resistivity tomography. In the application of 3-D resistivity tomography to the real field data set acquired at the quarry mine, we could derive a very reasonable and accurate image of the subsurface.

FFC2Q Model for NPS Load Analysis according to Characteristics of Early Stage of Runoff (강우 초기특성에 따른 비점오염부하량 산정을 위한 FFC2Q 모형)

  • Lee, Jong-Tae;Seo, Kyung-A;Hur, Sung-Chul
    • Journal of Korea Water Resources Association
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    • v.43 no.3
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    • pp.245-256
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    • 2010
  • We study the basic theory and applicability of the WQUAL block in the FFC2Q model and the characteristics of non-point pollutant loads during the early stage of runoff. Study is also performed on selection of the values of the related parameters and their effect on the simulation results. FFC2Q simulation results are compared for verification with the measured data for three rainfall events in the Gunja Subbasin and found to be similar to the measured data in peak-flows, total runoff volumes, total loads, peak concentrations and times of peak concentration. This model thus shows results very close to those applying the SWMM and MOUSE models, even though it uses simplified input data. Related to rainfall distribution, under the condition of Huff 1st quartile distribution the pollutant loads occurred earlier than under other conditions, and in the early stage of rainfall the BOD and COD loads increased faster than the SS loads. The NPS loads were concentrated in the early stage of rainfall and finally reached total loads, so the rainfall after that could not contribute so much to the NPS loads.

Improvement of Soil Quality for Artificial Planting's Ground with Large Integrated Underground Parking Lot in Apartment Complex (대규모 지하통합주차장을 갖는 공동주택 인공식재지반 토양품질 개선방안)

  • Kang, Myung-Soo;Lee, Eun-Yeob;Lee, Jung-Min;Kim, Mi-Na
    • Land and Housing Review
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    • v.6 no.1
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    • pp.31-39
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    • 2015
  • Most landscape areas in apartment complex have been changing. Increasing the area of underground parking lots have an effect on apartment's circumstance. Natural ground was decreased so that the most space in apartment complex were converted into an artificial ground. To suggest the soil quality management, this study examined the actual situation about the soil quality of planting ground such as the quality standard as artificial soil, the difference of natural ground, and the difference of soil quality according to the work classification. As a result, the soil quality of the apartment complex with a large underground parking lot had low quality of soil. Soil physical properties were relatively fine but soil chemical properties needed the quality control. The soil quality of natural ground and artificial ground was not statistically significant and the soil quality by the work classification also had no statistical significance. Therefore, we established improvements about standards of the chemical properties for quality management, the soil quality in the natural ground and applying the equivalent standard according to the work classification.

Physical Properties of Dredged Sand Treated by Washing and Sorting Dredged Soil (하천준설토를 세척 선별한 준설모래의 물리적 특성)

  • Lee, Yun-Seong;Lee, Sang-Soo;Song, Ha-Young;Bae, Kee-Sun;Lee, Sung-Bok;Lee, Do-Heun
    • Land and Housing Review
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    • v.1 no.1
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    • pp.35-42
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    • 2010
  • Most of the dredged sand generated from the sewage pipe maintenance project and the government's four-river project are disposed depending on abandonment and filling-up. This is caused by the lack of related recycling technology using dredged sand appropriately and high absorption rate and micro-particles of dredged sand producted from existing sand production system. Thus, this study carried out a quality assessment for the dredged sand produced through the optimum washing and sorting system supplementing problems of existing dredged sand production system as a part of research to examine performance of removing micro-particles and foreign substances. As a result of the assessment, the dredged sand produced through the cleaning and sorting system showed a wide quality improvement effect in absorption rate, 0.08 mm sieve pass amount, clay lump volume and organic impurity content, and it turned out to satisfy both the quality standards of this study, KS F 2573(recycled aggregate for concrete) and KS F 2526(aggregate for concrete) so it could be confirmed that it would be able to be used as an aggregate for concrete in the future.

A Structural Analysis between Overseas Opening of Geospatial Information and the Promotion of Geospatial Information Industry Using the Systems Thinking (시스템 사고를 통한 지도데이터 국외개방과 공간정보 산업 활성화간 인과구조 분석)

  • Yi, Mi Sook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.4
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    • pp.213-221
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    • 2018
  • South Korea has been reluctant to open its geospatial information overseas to ensure security as a divided country. However, this cannot continue as the domestic and international environments related to geospatial information and the industrial ecosystem of information and communication technologies have been changing dramatically. Within this context, this study aims to analyze the causal relations among relevant variables and how they change and interact with time using a systems thinking process. First, causal maps were created for the domains of national security, map-based convergence service, and corporate competition. Then, the causal maps for each domain were integrated, based on which the points for policy intervention and dominant feedback loops were identified. The analysis results showed that securing the self-sufficiency of domestic geospatial businesses is a key element to determine the whole causal map, and the variable that changes the dominant feedback loop from a vicious circle to a virtuous one is the decision to open geospatial information overseas. In this study, I found the policy leverage that is a policy intervention point that can produce a great effect with little input by building a causal map of the interactions between major variables. This study is significant in that it identified and analyzed the dominant feedback loop as to which causal structure would dominate the system in the long term. The results of this study can be used to discuss not only the impacts of map data overseas opening on the national security and geospatial information industry, but also the interactions in the future when Google or other global companies request to release the geospatial information.

Parametric Study on 3-way Switch Design Considering Levitation Stability of Maglev Train (자기부상열차의 부상안정성을 고려한 3방향 분기기의 설계 파라미터 연구)

  • Lee, Younghak;Han, Jong-Boo;Lim, Jaewon;Lee, Jong-Min
    • Journal of the Korean Society for Railway
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    • v.19 no.2
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    • pp.135-144
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    • 2016
  • It is essential to lighten the weight of switch girders in order to reduce their costs of manufacturing and make it easier to use them in construction. Lightening the weight of switch is also important to the Maglev 3-way switches system, however, the design variables should be considered very carefully if lightening is to be applied to the system, because these variables are vitally related to the levitation stability. Because Urban Maglev trains have a structure in which train bogie wraps around the guiderail, the adjustment of a girder's height is a possible way to reduce the weight. The safety of the application of this concept is ensured by repeated experiments in a test bed, however, due to a lack of space and budget limits, the design parametric study for the system model can substitute for actual application. The purpose of this paper is to study the design parameters that are concerned with levitation stability while a Maglev train is running on the Maglev 3-way system depending on the weight of the switch girders. In this study, switch girder weight is reduced by adjustment of girder height and girders are and modeled as a flexible body. The effect of the adjustment of girder height on the levitation stability can be analyzed by comparing the velocity of the train when it passes the switch girders, with the lateral gap, and the levitation gap which are obtained from the co-simulation of the Maglev train's dynamics model and flexible switching system. The results of this research will be used to design a Maglev switch.

An Experimental Study on the Properties of Engineering and Shrinkage Cracking Reduction of Fiber Reinforced Concrete Using Recycled Fine Aggregate (섬유보강 순환잔골재 콘크리트의 공학적 특성 및 수축균열저감특성에 관한 실험적 연구)

  • Kim, Gyu-Yong;Nam, Jeong-Soo;Kim, Moo-Han;Lee, Do-Heun;Song, Ha-Young
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.3
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    • pp.82-89
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    • 2009
  • Recently, the study is progressing actively about manufacture skill of concrete for promoted recycled aggregate and concrete made into recycled aggregate in the construction production field. But, application and study about recycled fine aggregate insufficient compared to recycled coarse aggregate. So, in this study, it presents basic data for development of environmental load reduction fiber reinforcement recycled fine aggregate concrete by comparison and investigation about engineering properties and shrinkage cracking of fiber reinforcement recycled find aggregate concrete for increasing shrinkage cracking reduction and long term stability of environmental load reduction concrete used recycled fine aggregate. In the result of the study, compared to natural fine aggregate, a crack-extent increased by applying recycled fine aggregate, moreover, as a water cement ratio increased, the crack size increased, as well. In addition, it's shown that the specimen mixed with PVA and Nylon, among all kinds of fibers, showed the smallest crack size, so it's verified that the mix of fiber had an effect on decreasing crack-extent.

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Effective PPG Signal Processing Method for Detecting Emotional Stimulus (감성 자극 판단을 위한 효과적인 PPG 신호 처리 방법)

  • Oh, Dong-Gi;Min, Byung-Seok;Kwon, Sung-Oh;Kim, Hyun-Joong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.5C
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    • pp.393-402
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    • 2012
  • In this study, we propose a signal processing algorithm to measure the arousal level of a human subject using a PPG(Photoplethysmography) sensor. From the measured PPG signals, the arousal level is determined by PPI(Pulse to Pulse Interval) and discrete-time signal processing. We ran psychophysical experiments displaying visual stimuli on TV display while measuring PPG signal from a finger, where the nature landscape scenes were used for restorative effect, and the urban environments were used to stimulate the stress. However, the measured PPG signals may include noise due to subject movement and measurement error, which results in incorrect detections. In this paper, to mitigate the noise impact on stimulus detection, we propose a detecting algorithm using digital signal processing methods and statistics of measured signals. A filter is adopted to remove a high frequency noise and adaptively designed taking into account the statistics of the measured PPG signals. Moreover we employ a hysteresis method to reduce the distortion of PPI in decision of emotional. Via experiment, we show that the proposed scheme reduces signal noise and improves stimulus detection.