• Title/Summary/Keyword: Poor ground

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Development and Verification of A Module for Positioning Buried Persons in Collapsed Area (붕괴지역의 매몰자 위치측위를 위한 모듈 개발 및 검증)

  • Moon, Hyoun-Seok;Lee, Woo-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.427-436
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    • 2016
  • Due to disasters such as earthquakes and landslides in urban areas, persons have been buried inside collapsed buildings and structures. Rescuers have mainly utilized detection equipment by applying sound, video and electric waves, but these are expensive and due to the directional approaches onto the collapsed site, secondary collapse risk can arise. In addition, due to poor utilization of such equipment, new human detection technology with quick and high reliability has not been utilized. To address these issues, this study develops a wireless signal-based human detection module that can be loaded into an Unmanned Aerial Vehicle (UAV). The human detection module searches for the 3D location for buried persons by collecting Wi-Fi signal and barometer sensors data transmitted from the mobile phones. This module can gain diverse information from mobile phones for buried persons in real time. We present a development framework of the module that provides 3D location data with more reliable information by delivering the collected data into a local computer in the ground. This study verified the application feasibility of the developed module in a real collapsed area. Therefore, it is expected that these results can be used as a core technology for the quick detection of buried persons' location and for relieving them after disasters that induce building collapses.

Effects of Greenhouse Orientation on the Greenhouse Environment and the Growth of Tomato in Forcing Culture (시설방향이 시설내 환경과 촉성재배 토마토 생육에 미치는 영향)

  • Choi, Young-Hah;Park, Kyoung-Sub;Kang, Nam-Jun;Kim, Hong-Lim;Kwak, Yong-Bum;Kim, Heung-Deug;Goo, Dae-Hoe;Cho, Myoung-Hwan
    • Journal of Bio-Environment Control
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    • v.19 no.1
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    • pp.6-11
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    • 2010
  • This experiment was conducted to investigate the effect of greenhouse orientation on the greenhouse environment and the growth and yield of tomato cv 'Momotaro-Yoku' in forcing culture. The photosynthetic phpton flux density (PPFD) of a.m was higher in north-south orientation than that in east-west orientation and it was opposed in the p.m. Mean PPFD of a day was higher in east-west orientation than that in north-south orientation because the light transmitting area became larger in east-west orientation with decrease of incidence angle. The PPFD at 60 cm point above ground of all furrows was poor due to shadows near plants and it was higher in north-south orientation than that in east-west orientation. The air temperature in the greenhouse was higher in east-west orientation than that in north-south orientation but there was no significant difference since mid February as solar altitude goes up. The soil temperature was some higher in east-west orientation than that in north-south orientation and there was not significant difference among ridges. In east-west orientation, as ripening was promoted, high early yield of tomato were obtained. So total yield was greater about 8% in east-west orientation than that in north-south orientation. Therefore, it was considered that east-west orientation is more advantageous than north-south orientation for forcing culture of tomato.

Seasonal Variation in Community Structure of Subtidal Seaweeds in Jeju Island, Korea (제주도 주변 해역 조하대 해조류 군집구조의 계절적 변동)

  • Kim, Bo Yeon;Ko, Jun-Cheol;Ko, Hyuck Joon;Park, Sung Eun;Cha, Hyung Kee;Choi, Han Gil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.607-618
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    • 2013
  • Marine macroalgal community structures and characteristics of ocean environmental factors were examined seasonally at four sites in Jeju Island, Korea, from March to November 2012. A total of 71 macroalgal species were identified, including 9 green, 7 brown, and 55 red algae. Peyssonnelia capensis occurred at all study sites and in all seasons. The average annual biomass of seaweed was 991.84 g wet $wt/m^2$, with seasonal variations from 543.80 g in autumn to 1,284.17 $g/m^2$ in summer. A green alga, Codium coactum, was the dominant species, occupying 21.31% (211.39 $g/m^2$) of the total algal biomass in Jeju Island. Subdominant species were Ecklonia cava and Lithophyllum okamurae, comprising 20.85% (206.75 $g/m^2$) and 19.64% (194.75 $g/m^2$), respectively, of the total algal biomass in Jeju Island. The vertical distribution of subtidal seaweeds was represented by L. okamurae at 5 m depth, C. coactum at 10 m depth, E. cava at 5-10 m depth and P. capensis at the 20 m depth level. In the present study, crustose coralline algae, which predominated on barren ground, were subdominant species at all study sites. Community indices varied between 0.51-0.63 for dominance index (DI), 5.53-8.14 for richness index (R), 0.51-0.63 for evenness index (J'), and 2.04-2.32 for diversity index (H'). On the basis of seaweed biomass and community indices, Sinchang was the best preserved coastal area, showing maximal values in biomass, and evenness- and diversity-indices, and minimal value in the dominance index, representing stable environmental conditions. In contrast, the Onpyung and Topyeong sites, located near tourist venues such as Udo and Seogwipo were relatively poor habitats based on community indices and biomass. The present results could imply that climate changes alter seaweed community structure, and long-term monitoring of the study sites is required.

Health Status in Urban Slum Area (일부(一部) 도시(都市) 영세지역(零細地域)의 보건실태(保健實態))

  • Chang, Im-Won;Chung, Kyou-Chull
    • Journal of Preventive Medicine and Public Health
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    • v.10 no.1
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    • pp.3-15
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    • 1977
  • In order to find out health problems among inhabitants in slum areas in Kwanak-Ku, Seoul, a series of health survey was conducted upon 510 households by interview from March to December, 1976. The results obtained were as follows: 1. Employments of householders were unstable; Out of 508 householders, 164(32.3%) were unemployed and 184 (36.2%) were daily or temporary employees. 2. Average number of households per house was 2.0 and average area of residential room per person was $4.0m^2$. 3. 476(93.3%) out of 510 households were supplied with tap water and rest of them made use of ground water as a source of drinking water. 4. Only 279(18.3%) out of 1527 live births were delivered at medical facilities, 496(32.7%) were at home attended by doctors or midwives and 358(25.1%) took prenatal care. The above findings were worse in urban slum area than in other urban area of relatively high economic level, but were better than in rural area of less medical facilities. 5. Initiation of treatment were delayed until their illnesses were advanced in most of the households, 472(92.5%) out 510. In the early stage of the illness, 131(25.6%) of the house-holds sought physicians in their clinics or general hospitals and 250 (40.9%) visited chemists, to toy drugs at first hand. Frequency of visits to physician increased to 52.8% as the disease aggravated in later stages. 6. Cost of medical expenditure per household amounted to 815 won, and was paid to, in the order of chemists, physicians, chinese herb stores, chinese herb doctors. 7. Concerning the health knowledge of the inhabitants, 273(53.9%) out of 506 respondents were aware of the infectivity of pulmonary tuberculosis, and 68(13.4%) of them checked regularly their chest findings by X-ray at least once every two years. 8. As for the family planning, although 448(87.3%) out of 510 respondents were in favor of it, 215 (41.8%) of them were actually practicing contraception. 9. About 40.6% (125 respondents) of them obtained information and knowledge concerning contraception through personal contact with family planning workers. 10. Nutritional status of housewives was generally poor: 49(38.3%) out of 128 housewives were found to be anemic and average serum protein level was $7.5{\pm}0.82g/dl$.

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Comparison of Ultimate Bearing Capacity Formulas for Single Stone column in Bulging and General shear failure using in-situ test results (현장 시험치를 이용한 단일 쇄석다짐말뚝의 Bulging 및 General Shear Failure시의 극한지지력 제안식에 관한 비교 연구)

  • Chun, Byung-Sik;Kim, Won-Cheul;Seo, Deok-Dong
    • Journal of the Korean GEO-environmental Society
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    • v.4 no.2
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    • pp.65-76
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    • 2003
  • Stone column is a soil improvement method and can be applicable for loose sand or weak cohesive soil. Since the lack of sand, stone column seems one of the most adaptable approach for poor ground as a soil improvement technique. However, this method was not studied for practical application. In this paper, the bearing capacity of single stone column at the Gaduk, Ulsan and Gwangyang under the bulging and general shear failure mode were compared with those of the suggested formulas. Especially, a test result of single stone column at the Busan area by static load was compared with the bearing capacity of suggested formulas. The analysis results showed that there were not much bearing capacity differences among those suggested bearing capacity formulas. However, the bearing capacity by static load test was almost double of those with suggested formula. The result also showed that the undrained shear strength was the most important parameter for the bearing capacity estimation of stone column.

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A study on the effect of support structure of steel rib in partitioning excavation of tunnel (터널 상·하반 분할 굴착 시 강지보재 지지구조 효과에 대한 연구)

  • Kim, Ki-Hyun;Kim, Yeon-Deok;Hwang, Beoung-Hyeon;Choi, Yong-Kyu;Kim, Sang-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.5
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    • pp.543-561
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    • 2020
  • This paper is the result of the study on the effect of the support structure of the tunnel steel rib. In tunnel excavation, the top and bottom half excavation methods result in subsidence of steel rib reinforcement due to insufficient support of steel rib reinforcement when the ground is poor after excavation. The foundation of the steel rib installed in the upper half excavates the bottom part of the base, causing the subsidence to occur due to various effects such as internal load and lateral pressure. As a result, the tunnel is difficult to maintain and its safety is problematic. To solve these problems, steel rib support structures have been developed. For the purpose of verification, the behavior of the supporting structure is verified by model experiments reduced to shotcrete and steel rib material similarity, the numerical analysis of ΔP and ΔP generated by bottom excavation by Terzaghi theoretical equation. As a result, it was found that the support structure of 20.100~198.423 kN is required for the 10~40 m section of the depth for each soil of weathered soil~soft rock. In addition, as a result of the reduced model experiment, a fixed level of 50% steel rib deposit of steel rib support structure was installed. The study shows that the installation of steel rib support structures will compensate for uncertainties and various problems during construction. It is also thought that the installation of steel rib support structure will have many effects such as stability, economy, and air reduction.

Analysis of the under Pavement Cavity Growth Rate using Multi-Channel GPR Equipment (멀티채널 GPR 장비를 이용한 도로하부 공동의 크기 변화 분석)

  • Park, Jeong Jun;Kim, In Dae
    • Journal of the Society of Disaster Information
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    • v.16 no.1
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    • pp.60-69
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    • 2020
  • Purpose: Cavity growth process monitoring is to periodically monitor changes in common size and topography for general and observational grades to predict the rate of common growth. The purpose of this study is to establish a systematic cavity management plan by evaluating the general and observational class community in a non-destructive method. Method: Using GPR exploration equipment, the acquired surface image and the surrounding status image are analyzed in the GPR probe radargram in depth, profile, and cross section of the location. The exact location is selected using the distance and surrounding markings shown on the road surface of the initial detection cavity, and the test cavity is analyzed by calling the radar at the corresponding location. Result: As a result of monitoring tests conducted at a cavity 30 sites of general and observation grade, nine sites have been recovered. Changes in scale were seen in 21 cavity locations, and changes in size and grade occurred in 13 locations. Conclusion: The under road cavity is caused by various causes such as damage to the burial site, poor construction, soil leakage caused by groundwater leakage, waste and ground vibration. Among them, indirect factors could infer the effects of groundwater and localized rainfall.

A STUDY FOR THE DETERMINATION OF KOMPSAT I CROSSING TIME OVER KOREA (I): EXAMINATION OF SOLAR AND ATMOSPHERIC VARIABLES (다목적 실용위성 1호의 한반도 통과시각 결정을 위한 연구 (I): 태양 및 대기 변수 조사)

  • 권태영;이성훈;오성남;이동한
    • Journal of Astronomy and Space Sciences
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    • v.14 no.2
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    • pp.330-346
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    • 1997
  • Korea Multi-Purpose Satellite I (KOMPSAT-I, the first multi-purpose Korean satellite) will be launched in the third quarter of 1999, which is operated on the sun-synchronous orbit for cartography, ocean color monitoring, and space environment monitoring. The main mission of Electro-Optical Camera(EOC) which is one of KOMPSAT-I sensors is to provide images for the production of scale maps of Korea. EOC collects panchromatic imagery with the ground sample distance of 6.6m at nadir through visible spectral band of 510~730nm. For determining KOMPSAT-I crossing time over Korea, this study examines the diurnal variation of solar and atmospheric variables that can exert a great influence on the EOC imagery. The results are as follows: 1) After 10:30 a.m. at the winter solstice, solar zenith angle is less than $70^{\circ}$ and expected flux of EOC spectral band over land for clear sky is greater than about $2.4mW/cm^2$. 2) For daytime the distribution of cloud cover (clear sky) shows minimum (maximum) at about 11:00 a.m. Although the occurrence frequency of poor visibility by fog decreases from early morning toward noon, its effect on the distribution of clear sky is negligible. From the above examination it is concluded that determining KOMPSAT-I crossing time over Korea between 10:30 and 11:30 a.m. is adequate.

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A Case of Pneumonia Caused by Pneumocystis jirovecii Resistant to Trimethoprim-Sulfamethoxazole

  • Lee, Sang Min;Cho, Yong Kyun;Sung, Yon Mi;Chung, Dong Hae;Jeong, Sung Hwan;Park, Jeong-Woong;Lee, Sang Pyo
    • Parasites, Hosts and Diseases
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    • v.53 no.3
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    • pp.321-327
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    • 2015
  • A 50-year-old male visited the outpatient clinic and complained of fever, poor oral intake, and weight loss. A chest X-ray demonstrated streaky and fibrotic lesions in both lungs, and chest CT revealed multifocal peribronchial patchy ground-glass opacities with septated cystic lesions in both lungs. Cell counts in the bronchoalveolar lavage fluid revealed lymphocyte-dominant leukocytosis, and further analysis of lymphocyte subsets showed a predominance of cytotoxic T cells and few T helper cells. Video-assisted wedge resection of the left upper lobe was performed, and the histologic examination was indicative of a Pneumocystis jirovecii infection. Trimethoprim-sulfamethoxazole (TMP-SMX) was orally administered for 3 weeks; however, the patient complained of cough, and the pneumonia was aggravated in the follow-up chest X-ray and chest CT. Molecular studies demonstrated mutations at codons 55 and 57 of the dihydropteroate synthase (DHPS) gene, which is associated with the resistance to TMP-SMX. Clindamycin-primaquine was subsequently administered for 3 weeks replacing the TMP-SMX. A follow-up chest X-ray showed that the pneumonia was resolving, and the cough was also alleviated. A positive result of HIV immunoassay and elevated titer of HCV RNA indicated HIV infection as an underlying condition. This case highlights the importance of careful monitoring of patients with P. jirovecii pneumonia (PCP) during the course of treatment, and the molecular study of DHPS mutations. Additionally, altering the anti-PCP drug utilized as treatment must be considered when infection with drug-resistant P. jirovecii is suspected. To the best of our knowledge, this is the first case of TMP-SMX-resistant PCP described in Korea.

Estimation of Countermeasures and Efficient Use of Volume of Artificial Reefs Deployed in Fishing Grounds (어초어장으로 시설된 사각형어초의 수량 산정 및 유효공용적 평가)

  • Kim, Ho-Sang;Lee, Jeong-Woo;Kim, Jong-Ryeol;Yoon, Han-Sam
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.3
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    • pp.181-187
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    • 2009
  • To estimate the status and volume of artificial reefs(ARs) deployed at the sea bottom in fishing grounds, this study assessed the initial volume of ARs, the cubic volume of AR groups, and the porosity of each AR using image data collected during a survey using a multi-beam echo sounder(MBES) and a side scan sonar(SSS). These results were compared with data collected during diver surveys and used to develop a new method and prediction formulas for countermeasures, facility volume, and efficient use of volume for deployed ARs(cubic concrete). The field survey results for nine ARs deployed in the Busan Sea region were calculated, and the average value of coefficient k(indicating the efficient use of volume ratio) among ARs was 0.753, and the correlation between coefficient k and year(Yr) of deployment was calculated as k=0.0023Yr+0.725. The relationship between these two factors was poor. In years following the deployment of artificial reefs, coefficient k and year of deployment were not correlated, in spite of the hardening ground due to subsidence and the reduced distance between ARs. Consequently, it is reasonable to suppose that coefficient k was defined by bottom surface conditions and initial deployment conditions.

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