• Title/Summary/Keyword: Natural Recovery

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Decision of River Rehabilitation Plan using Multi-criteria Decision Making (다기준 의사결정을 활용한 자연형 하천 대안 선정)

  • Cho, Hong-Je;Hwang, Jae-Ho;Yoon, Jong-Chun
    • Journal of Wetlands Research
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    • v.12 no.2
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    • pp.87-93
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    • 2010
  • River restoration plan and selection method are needed to reflect the diversity of river. Meanwhile, the ultimate purpose of river restoration is natural recovery of the river. Recently. hydrophilic enhancement is a tendency to include. In this study, naturalness of a river was used to establish alternative for the natural river recovery. Also, naturalness of a river calculated by using the evaluation of river naturalness that was developed using multi-criteria decision making to fit the environmental conditions in Korea. After selection the evaluation items for assessing the naturalness of the river based on the characteristics of the river, multiple alternatives were constructed and the naturalness of river for each of those alternatives were estimated. Comparing the estimated values has made the measurement of the natural recovery effect for each alternative efficient.

Error estimation for 2-D crack analysis by utilizing an enriched natural element method

  • Cho, J.R.
    • Structural Engineering and Mechanics
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    • v.76 no.4
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    • pp.505-512
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    • 2020
  • This paper presents an error estimation technique for 2-D crack analysis by an enriched natural element (more exactly, enriched Petrov-Galerkin NEM). A bare solution was approximated by PG-NEM using Laplace interpolation functions. Meanwhile, an accurate quasi-exact solution was obtained by a combined use of enriched PG-NEM and the global patch recovery. The Laplace interpolation functions are enriched with the near-tip singular fields, and the approximate solution obtained by enriched PG-NEM was enhanced by the global patch recovery. The quantitative error amount is measured in terms of the energy norm, and the accuracy (i.e., the effective index) of the proposed method was evaluated using the errors which obtained by FEM using a very fine mesh. The error distribution was investigated by calculating the local element-wise errors, from which it has been found that the relative high errors occurs in the vicinity of crack tip. The differences between the enriched and non-enriched PG-NEMs have been investigated from the effective index, the error distribution, and the convergence rate. From the comparison, it has been justified that the enriched PG-NEM provides much more accurate error information than the non-enriched PG-NEM.

Ecological Recovery of Contaminated Dredged Materials in Masan Bay, Korea (마산만 오염 준설토사의 생태회복)

  • Lee, Chan-Won;Jeon, Hong-Pyo;Ha, Kyung-Ae
    • Journal of Environmental Science International
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    • v.17 no.1
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    • pp.29-36
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    • 2008
  • A large amount of $2.1{\times}10^6m^3$ of polluted sediment was dredged from the Masan Bay and deposited in Gapo confined area, Masan, Korea. The six representative sediments were obtained and analyzed for issue components. The data was discussed with the species of benthos and their distribution. It was judged that toxicological effects of sediment analyzed ranged from ERL to ERM with copper and zinc, and ERL with cadmium, chrome, lead and nickel by the Adverse Biological Effects. The dredging index (DI) of sediments stabilized for 10 years since dumping the confined site was calculated and compared with the DI values of dredged sediment itself. DI values decreased from 0.67 to $0.07{\sim}0.18$, which reflects DI value less than 0.2 is good for benthos in the sediment by the natural recovery of dredged materials. The ecological recovery was confirmed in this confined area as a habitat of benthic organisms.

Histological Changes in Reproductive Organs of Pubescent Male Mice in Response to ICI 182, 780 Treatment and Recovery of the Organs with Time (ICI 182, 780을 투여한 사춘기 수컷 생쥐 생식기관의 조직학적 변화와 시간에 따른 회복)

  • Mo, Yun Jeong;Choi, Hayana;Cho, Young Kuk;Park, Mi Suk;Cho, Hyun Wook
    • Journal of Life Science
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    • v.25 no.12
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    • pp.1415-1424
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    • 2015
  • ICI 182, 780 (ICI) has been used as an estrogen receptor inhibitor in several mammalian species. This study was conducted to observe histological changes in the reproductive system of pubescent male mice following ICI treatment, as well as to investigate the recovery of the organs over time. To accomplish this, ICI at 5 mg/0.1 ml of castor oil was subcutaneously injected into 5-week-old male mice once per week for 4 weeks. The mice were then randomly divided into no-recovery, 150-day recovery, and 300-day recovery groups. The testis of the no-recovery group showed atrophy of the seminiferous tubules, with decreased Sertoli cell numbers and thickness of the germinal epithelium. In the epididymis, the cell height of epithelial tissues was altered, but these changes were not observed in the 300-day recovery group. In the efferent ductule, the luminal diameter was increased, but the cell height of the epithelial tissues was decreased. In the prostate and seminal vesicles, the cell height of the epithelial tissues was increased, and these changes were not observed in the 150-day recovery group. These results show that ICI causes histological changes in pubescent male reproductive organs but that these changes are resolved with time.

Parameter Recovery for LIDAR Data Calibration Using Natural Surfaces

  • Lee Impyeong;Moon Jiyoung;Kim Kyoung-ok
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.642-645
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    • 2004
  • This paper focuses on recovering systematic biases during LIDAR calibration, particularly using natural surfaces as control features. Many previous approaches have utilized all the points overlapping with the control features and often experienced with an inaccurate value converged with a poor rate due to wrong correspondence in pairing a point and the corresponding control features. To overcome these shortcomings, we establish a preventive scheme to select the pairs of high confidence, where the confidence value is based on the error budget associated with the point measurement and the linearity and roughness of the control feature. This approach was then applied to calibraring the LIDAR data simulated with the given systematic biases. The parameters were successfully recovered using the proposed approach with the accuracy and convergence rate superior to those using the previous approaches.

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Comparison of Dysphagia Rehabilitation Therapy with Natural Recovery on Swallowing Ability among Acute Stroke Patients (연하재활치료의 효과와 자연회복과의 비교연구 - 급성기 뇌졸중 환자를 중심으로 -)

  • Heo, S.Y.;Kim, K.K.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.8 no.2
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    • pp.109-118
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    • 2014
  • The purpose of this study was to compare the effectiveness of rehabilitation therapy with natural recovery in patients who had dysphagia due to stroke. Swallowing functions were examined on a total of 98 patients with stroke-caused dysphagia based on a videofluoroscopic swallowing study (VFSS) for 8 weeks. The each group was evaluated with DOSS, DSS and FOSS to assess swallowing ability in the first week and re-evaluated in the $8^{th}$ week during the session for investigating the recovery status. The author compared the above initial data and follow-up data using a Mann-Whitney U test, Kruskal-Wallis test and Wilcoxon's Signed Rank test, ANCOVA to confirm statistically controlling for the effects of other continuous variables, performed by IBM SPSS Statistics 20.0 for windows. There was statistically significant recovery in the experimental group except measure of DOSS (p>0.05). In the control group, it showed improvement in all the scales(p<0.05). After terminating each session, the comparison of the two group of patients showed statistical significant differences in DSS and FOSS(p<0.05). These results suggest that possibility of natural neurologic recovery has positive effects on early stage of dysphagia caused by stroke.

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Thermodynamic analysis of a combined gas turbine power plant with a solid oxide fuel cell for marine applications

  • Welaya, Yousri M.A.;Mosleh, M.;Ammar, Nader R.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.5 no.4
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    • pp.529-545
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    • 2013
  • Strong restrictions on emissions from marine power plants (particularly $SO_x$, $NO_x$) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and gas turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. It includes a study of a heat-recovery system for 18 MW SOFC fuelled by natural gas, to provide the electric power demand onboard commercial vessels. Feasible heat-recovery systems are investigated, taking into account different operating conditions of the combined system. Two types of SOFC are considered, tubular and planar SOFCs, operated with either natural gas or hydrogen fuels. This paper includes a detailed thermodynamic analysis for the combined system. Mass and energy balances are performed, not only for the whole plant but also for each individual component, in order to evaluate the thermal efficiency of the combined cycle. In addition, the effect of using natural gas as a fuel on the fuel cell voltage and performance is investigated. It is found that a high overall efficiency approaching 70% may be achieved with an optimum configuration using SOFC system under pressure. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.

IoT-Based Module Development for Management and Real-time Activity Recognition of Disaster Recovery Resources (사물인터넷 기반 재난복구자원 관리 및 실시간 행동인지 모듈 개발)

  • Choe, Sangyun;Park, Juhyung;Han, Sumin;Park, Jinwoo;Chang, Tai-woo;Yun, Hyeokjin
    • The Journal of Society for e-Business Studies
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    • v.22 no.4
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    • pp.103-115
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    • 2017
  • Globally, frequency and scale of natural disasters are growing, also the damage is increasing. In view of the damage by natural disasters for several years, it is true that Korea is not free from such damages. In this paper, we propose a process to efficiently manage recovery resources in case of disaster damage. We utilize the IoT technology to detect the resource status in real time, and configure the process so that the state and movement of the recovery resource can be grasped in real time through the resource activity recognition module. In addition, we designed the database that is necessary to actualize it, and developed and experimented resource activity recognition module using smart-phone sensors. This will contribute to building a quick and efficient disaster response system.

RAPID RECOVERY OF PHOTOSYNTHESIS FROM PHOTOINHIBITION IS RELATED TO FATTY ACID UNSATURATION OF CHLOROPLAST MEMBRANE LIPIDS IN CHILLING-RESISTANT PLANTS

  • Moon, Byoung-Yong;Kang, In-Soon;Lee, Chin-Bum
    • Journal of Photoscience
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    • v.5 no.1
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    • pp.1-10
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    • 1998
  • The susceptibility of chilling-resistant spinach plants. and of chilling-sensitive squash plants to photoinhibition was compared in terms of the activity of photosystem II, in relation to the deuce of fatty acid unsaturation of chloroplast membrane lipids. From thylakoid membranes of the plants. monogalactosyl diacylgtycerol, digalactosyl diacylglycerol. sulfoquinovosyt diacylglycerol, and phosphatidylglycerol were seperated as major lipid classes. It was found that the content of cis-unsaturated fatty acids of phosphatidylglycerol was greater by 32% in spinach than that in squash. When leaf disks were exposed to light at 5$\circ$C, 15$\circ$C and 25$\circ$C, photochemical efficiency of photosystem II. measured as the ratio of the variable to the maximum fluorescence of chlorophyll, declined markedly in squash plants, as compared to spinach plants. When leaf disks were exposed to strong light in the presence of lincomycin, an inhibitor of protein synthesis in chloroplasts, photoinhibition was accelerated in the two types of plants. Moreover, lincomycin treatment abolished the differences in the degree of susceptibility to strong light, which had been observed between the two types of plants. When the extent of photoinhibition of photosystem II-mediated electron transport was compared in thylakoid membranes isolated from the two types of plants, there were no differences in the degree of inactivation of photosystem II activity. However, when intact leaf disks were exposed to strong light either at 10$\circ$C or at 25$\circ$C, and then were allowed to recover either at 17$\circ$C or at 25$\circ$C in dim light. chilling-resistant plants such as spinach and pea showed marked recovery from photoinhibition, in contrast to chilling-sensitive plants, such as squash and sweet potato. whose recovery was strongly dependent on the temperature. These findings are discussed in relation to the unsaturation of fatty acids in membrane phosphatidylglycerol. It appears that fatty acid unsaturation of membrane lipids accelerates the recovery of photosystem H from photoinhibition, without affecting the photo-induced inactivation process of photosystem II associated with photoinhibition.

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