• Title/Summary/Keyword: 최소안전율

Search Result 136, Processing Time 0.032 seconds

Behaviors of the High-profile Arch Soil-steel Structure During Construction (높은 아치형 지중강판 구조물의 시공 중 거동 분석)

  • 이종구;조성민;김경석;김명모
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.6
    • /
    • pp.71-84
    • /
    • 2003
  • The metallic shell of soil-steel structures are so weak in bending moment that it should sustain the applied load by the interaction of the backfill soil around the structures. The shell can be subjected to excessive bending moment during side backfilling or under live-load when the soil cover is less than the minimum value. The current design code specifies the allowable deformation and Duncan(1979) and McGrath et al.(2001) suggested the strength analysis methods to limit the moments by the plastic capacity of the shell. However, the allowable deformation is an empirically determined value and the strength analysis methods are based on the results of FE analysis, hence the experimental verification is necessary. In this study, the full-scale tests were conducted on the high-profile arch to investigate its behaviors during backfilling and under static live-loads. Based on the measurements, the allowable deformation of the tested structure could be estimated to be 1.45% of rise, which is smaller than the specified allowable deformation. The comparison between the measurements and the results of two strength analyses indicate that Duncan underestimates the earth-load moment and overestimates the live-load moment, while McGrath et al. predicts both values close to the actual values. However, as the predicted factors of safeties using two methods coincide with the actual factor of safety, it can be concluded that both methods can predict the structural stability under live-loads adequately when the cover is less than the minimum.

The Diagnosis of Pneumoniae Following Bone Marrow Transplantation by Bronchoscopy (골수이식후 기관지내시경을 이용한 폐렴의 진단)

  • Kim, Tae-Yon;Yoon, Hyeong-Kyu;Moon, Hwa-Sik;Park, Sung-Hak;Min, Chang-Ki;Kim, Chun-Choo;Jung, Jung-Im;Song, Jeong-Sup
    • Tuberculosis and Respiratory Diseases
    • /
    • v.49 no.2
    • /
    • pp.198-206
    • /
    • 2000
  • Background : Pulmonary complications following bonemarrow transplantation (BMT) are common and associated with a high mortality rate. We investigated the yield, safety, and impact of fiberoptic bronchoscopy (FOB) for diagnosis of postBMT pneumoniae. Methods : From May 1997 to April 2000, 56 FOBs were performed in 52 post BMT patients for clinical pneumoniae. BMT patients with respiratory symptoms and/or pulmonary infiltrates had a thoracic HRCT(high resolution computed tomography) and bronchoscopic examination including BAL (bronchoalveolar lavage), TBLB (transbronchial lung biopsy), PSB (protected specimen brush). Results : The characteristics of the subjects were as follows : 37 males, 15 females, mean age of 31.3 years(l7-45), 35 sibling donor allogenic BMTs, 15 nonrelated donor allogenic BMTs, and 2 autologous BMTs. Fiftynine percent of FOBs (33 FOBs, 31 patients) were diagnostic. Isolated pathogens included the following : 12 cytomegalovirus (CMV) (21.4 %), 7 pneumocystis carinii (PC) (12.5 %), 11 CMV with PC (19.6 %), 2 Mycobacaterium tuberculosis (3.6%), and 1 streptococcus (1.8%). Most of the radiographic findings were diffuse interstitial lesions. CMV pneumoniae had mainly diffuse interstitial nodular lesion, and PC pneumoniae had diffuse, interstitial ground glass opacity(GGO). When CMV was accompanied by PC, a combined pattern of nodular and GGO was present. Of the 56 cases (23.2%), 13 died of CMV pneumoniae (n=2), PCP (n=2),mixed infection with CMV and PC (n=3), underlying GVHD (n=1), underlying leukemia progression (n=1), or respiratory failure of unknown origin (n=4). There was no major complication by bronchoscopy. Only 3 cases developed minor bleeding and 1 episode temporary hypoxemia. Conclusion : Based on our findings, CMV and PC are the major causes of postBMT pneumoniae. In addition, BAL can be considered a safe and accurate procedure for the evaluation of pulmonary complications after BMT.

  • PDF

Consideration on Ways to Reduce a Edge Pressure at Bottom Plate of Caisson Breakwaters (케이슨 방파제 바닥판 단부 지지력 저감방안에 대한 고찰)

  • Park, Woo-Sun;Lee, Byeong Wook
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.32 no.5
    • /
    • pp.331-339
    • /
    • 2020
  • In this study, ways to reduce the edge pressure at the bottom plate of the caisson breakwater were considered. The water depth, freeboard, design wave height and period, and the location of the center of gravity on the super-structure of the breakwater were selected as key design variables that influence the edge pressure, and analyzed how the edge pressure changes according to the change of this key variables. The pressure distribution formulae suggested in the design standard was applied for the calculation of design wave forces. Based on the wave forces, the required effective self-weight of the super-structure and the minimum width of the caisson were determined to have a safety factor of 1.2 against sliding and overturning. From the results, it was found that the edge pressure rapidly increased as the water depth increased, and could exceed the allowable bearing capacity when it reached a certain water depth which is 20 m within the analysis conditions. It was also confirmed that the edge pressure gradually increased linearly as the freeboard increased, but decreased with the increase of the wave height and period. This edge pressure could be significantly reduced up to more than 20% by moving the center of gravity of the super-structure to the seaside, which is 5% of the caisson width. Based on the analysis results and the recently conducted research results, a method was proposed to reduce the edge pressure that can be used in the design.

Characteristic Evaluation of Exposed Dose with NORM added Consumer Product based on ICRP Reference Phantom (ICRP 기준팬텀 기반의 천연방사성핵종이 포함된 가공제품 사용으로 인한 피폭선량 특성 평가)

  • Yoo, Do Hyeon;Lee, Hyun Cheol;Shin, Wook-Geun;Choi, Hyun Joon;Min, Chul Hee
    • Journal of Radiation Protection and Research
    • /
    • v.39 no.4
    • /
    • pp.159-167
    • /
    • 2014
  • In Korea, July 2012, the law as called 'Act on Safety Control of Radioactive Rays Around Living Environment' was implemented to control the consumer product containing Naturally Occurring Radioactive Material (NORM), but, there are no appropriate database and effective dose calculation system. The aim of this study was to develop evaluation technique of the exposure dose with the use of the consumer products containing NORM and to understand the characteristics of the exposed dose according to the radiation type and energy. For the evaluate of exposure dose, the ICRP reference phantom was simulated by the MCNPX code based on Monte Carlo method, and the minimum, medium, maximum energy of alphas, betas, gammas from the representative NORM of Uranium decay series were used as the source term in the simulation. The annual effective doses were calculated by the exposure scenario of the consumer product usage time and position. Short range of the alpha and beta rays are mostly delivered the dose to the skin. On the other hand, the gamma rays mostly delivered the similar dose to all of the organs. The results of the annual effective dose with $1Bq{\cdot}g^{-1}$ radioactive stone-bed and 10% radioactive concentration were employed with the usage time of 7 hours 50 minute per day, the maximum annual effective dose of alphas, betas, gammas were calculated 0.0222, 0.0836, $0.0101mSv{\cdot}y^{-1}$, respectively.

Effect of weight of radio-transmitters on survival of Red-tongue viper snake (Gloydius ussuriensis) and Short-tailed viper snake (Gloydius saxatilis)in the radio-transmitter implantation (발신기 삽입시 발신기 무게가 쇠살모사(Gloydius ussuriensis)와 까치살모사(Gloydius saxatilis)의 생존에 미치는 영향)

  • Do, Min-Seock;Shim, Jae-Han;Choi, Young-Min;Yoo, Jeong-Chil
    • Journal of Wetlands Research
    • /
    • v.16 no.1
    • /
    • pp.85-92
    • /
    • 2014
  • In order to study the home range of the red-tongue viper snake (Gloydis ussuriensis) and the short-tailed viper snake (Gloydius saxatilis) belonging to the viperidae of squamat in Korea, we implanted radio-transmitters which were weighed less than 5% of individual mass in them and traced their location by radio-tracking. Surgeries for transmitter insertion were performed on 5 red-tongue viper snakes and 6 short-tailed viper snakes (total 11 individuals) and the average ratio of transmitter mass to body mass were 4.2% and 2.2%, respectively. After radio-transmitter implantation, all short-tailed viper snakes survived but 4 out of 5 red-tongue viper snakes did not survive during the convalescence stage, showing only 20% of survival rate. The results suggest that the ratio of transmitter mass to body mass should be less than 3.6% at least in these species, although previous studies have recommended various ranges from 1% to 7% as the acceptable ratios.

Evaluation of Striatal Dopamine Transporter Density using $[^{123}I]-{\beta}-CIT$ SPECT in Schizophrenic Patients Treated with Olanzapine: Pilot study (정신분열병 환자에서 Olanzapine 사용 전후의 $[^{123}I]-{\beta}-CIT$ SPECT를 이용한 Dopamine Transporter 변화: 준비조사)

  • Kim, Chul-Eung;Moon, Hey-Won;Choe, Won-Siek;Kim, Chang-Ho;Chi, Dae-Yoon
    • The Korean Journal of Nuclear Medicine
    • /
    • v.36 no.4
    • /
    • pp.224-231
    • /
    • 2002
  • Purpose: This pilot study was performed to understand the pharmacological effect of olanzapine, an atypical antipsychotic agent, on dopamine transporter in schizophrenic patients. Materials and Methods: Six patients (3 male, 3 female) with schizophrenia, who had not taken any psychotropic drugs for at least four weeks, were studied. Nuclear imaging using $[^{123}I]-{\beta}-CIT$ SPECT was obtained before and after 4-week treatment with olanzapine. Analysis of ROI on the striatum, caudate nucleus, and putamen was performed. Results: Post-treatment uptake was significantly increased in all the ROIs compared with pre-treatment uptake. Conclusion: This preliminary study with the small number of schizophrenic patients suggested an increase in uptake of dopamine transporter in the striatum, caudate nucleus, and putamen after 4-week treatment with olanzapine, which warrants a large-scaled controlled study to confirm the current findings.

Quality Classification and Its Application Based on Certification Standards of Kentucky Bluegrass(Poa pratensis L.) Seed (켄터키 블루그래스(Poa pratensis L.) 종자의 보증 기준에 따른 품질 분류와 적용)

  • Kim, Shin-Jae;Joo, Young-Kyoo;Lee, Jae-Pil;Kim, Doo-Hwan
    • Asian Journal of Turfgrass Science
    • /
    • v.23 no.2
    • /
    • pp.253-264
    • /
    • 2009
  • The purpose of seed certification is to preserve the genetic purity and identity of seed varieties. This study is to provide information concerning seed certification procedures and certification standards of Kentucky bluegrass especially used in golf courses. We analyzed data from the seed certification standards of three states (Washington, Idaho and Oregon) in U.S.A. The certification processes both field inspection and laboratory requirement satisfying the minimum seed quality standards. The seed harvesting field must be propagated with the specified class of seeds and requires an adequate isolated distance from other crops. Moreover, the field should be clean and free from the objectionable weeds. The seed analysis tests include a germination rate, a percentage of pure seed, contents of other crop seed, weed seed, and inert matter. The certification standards of the certified seed and the sod quality seed showed general similarity in all three states. The certification standards of the sod quality seed should have less than 0.02% of maximum weed seed. The certified seed should have less than 0.3% of maximum weed seeds. Those certification standards of seed quality should guaranty the quality of turfgrass establishment of golf course.

Detection of The Real-time Weather Information from a Vehicle Black Box (차량용 블랙박스 영상에서의 실시간 기상정보 검지)

  • Kang, Ju-mi;Lee, Jaesung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2014.10a
    • /
    • pp.320-323
    • /
    • 2014
  • Today is going with the advancement of intelligent transportation systems and traffic environment and helping to provide safe and convenient service through a mobile device work with the popularization of the vehicle black box. The traffic flow by a variety of causes is constantly changing, it is often unable to prepare the driver, depending on external factors can not be controlled by the power of the public, leading to a major accident. The system needs to pass the real-time weather data in the inter-operator to prevent this. The proposed detection algorithm weather information delivered real-time weather information for this paper. The weather condition is detected by using the contrast between the histogram of the motion of the wiper and the clear day algorithm. In general, the wiper is worked in extreme weather conditions that will have a value different contrast due to rain or snow. Situation was considered clear, snowy conditions, such as using it on a rainy situation. First, designated as ROI (Region Of Interest) of the minimum area that can be detected in order to reduce the amount of calculation for the wiper, the wiper, which was detected through the operation of the threshold Thresholding the brightness of the vehicle wiper. In addition, we distinguish the value of each meteorological situation by using contrast. Results was obtained to 80% for the snow conditions, a rainy situation.

  • PDF

Detection of Marine Oil Spills from PlanetScope Images Using DeepLabV3+ Model (DeepLabV3+ 모델을 이용한 PlanetScope 영상의 해상 유출유 탐지)

  • Kang, Jonggu;Youn, Youjeong;Kim, Geunah;Park, Ganghyun;Choi, Soyeon;Yang, Chan-Su;Yi, Jonghyuk;Lee, Yangwon
    • Korean Journal of Remote Sensing
    • /
    • v.38 no.6_2
    • /
    • pp.1623-1631
    • /
    • 2022
  • Since oil spills can be a significant threat to the marine ecosystem, it is necessary to obtain information on the current contamination status quickly to minimize the damage. Satellite-based detection of marine oil spills has the advantage of spatiotemporal coverage because it can monitor a wide area compared to aircraft. Due to the recent development of computer vision and deep learning, marine oil spill detection can also be facilitated by deep learning. Unlike the existing studies based on Synthetic Aperture Radar (SAR) images, we conducted a deep learning modeling using PlanetScope optical satellite images. The blind test of the DeepLabV3+ model for oil spill detection showed the performance statistics with an accuracy of 0.885, a precision of 0.888, a recall of 0.886, an F1-score of 0.883, and a Mean Intersection over Union (mIOU) of 0.793.

An Improved Online Algorithm to Minimize Total Error of the Imprecise Tasks with 0/1 Constraint (0/1 제약조건을 갖는 부정확한 태스크들의 총오류를 최소화시키기 위한 개선된 온라인 알고리즘)

  • Song, Gi-Hyeon
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.34 no.10
    • /
    • pp.493-501
    • /
    • 2007
  • The imprecise real-time system provides flexibility in scheduling time-critical tasks. Most scheduling problems of satisfying both 0/1 constraint and timing constraints, while the total error is minimized, are NP-complete when the optional tasks have arbitrary processing times. Liu suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on uniprocessors for minimizing the total error. Song et at suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on multiprocessors for minimizing the total error. But, these algorithms are all off-line algorithms. In the online scheduling, the NORA algorithm can find a schedule with the minimum total error for the imprecise online task system. In NORA algorithm, EDF strategy is adopted in the optional scheduling. On the other hand, for the task system with 0/1 constraint, EDF_Scheduling may not be optimal in the sense that the total error is minimized. Furthermore, when the optional tasks are scheduled in the ascending order of their required processing times, NORA algorithm which EDF strategy is adopted may not produce minimum total error. Therefore, in this paper, an online algorithm is proposed to minimize total error for the imprecise task system with 0/1 constraint. Then, to compare the performance between the proposed algorithm and NORA algorithm, a series of experiments are performed. As a conseqence of the performance comparison between two algorithms, it has been concluded that the proposed algorithm can produce similar total error to NORA algorithm when the optional tasks are scheduled in the random order of their required processing times but, the proposed algorithm can produce less total error than NORA algorithm especially when the optional tasks are scheduled in the ascending order of their required processing times.