• Title/Summary/Keyword: IAS

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Application of Immune Algorithm for Harmonic State Estimation (전력시스템 고조파 상태 추정에서 면역 알고리즘 적용)

  • Wang Yong-Peel;Park In-Pyo;Chung Hyeng-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.12
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    • pp.645-654
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    • 2004
  • The design of a measurement system to perform Harmonic State Estimation(HSE) is a very complex problem. In particular, the number of available harmonic analysis measurement instruments is always limited. Therefore, a systematic procedure is needed to design the optimal placement of measurement points. This paper presents an optimal algorithm of HSE which is based on an optimal placement of measurement points using Immune Algorithm (IAs). This IA-HSE has been applied to power system for the validation of an optimal algorithm of HSE. The study results have indicated an economical and effective method for optimal placement of measurement points using Immune Algorithm (IAs) in the HSE.

Insulin autoimmune syndrome associated with alpha-lipoic acid in a young woman with no concomitant disease (특이 병력 없는 젊은 여성에게서 알파리포산 투약 후 발생한 인슐린자가면역증후군)

  • Lee, Sang Bae;Lee, Min Young;You, Ji Hong;Kim, Seong Han;Nam, Ji Sun
    • Journal of Yeungnam Medical Science
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    • v.34 no.1
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    • pp.115-118
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    • 2017
  • Insulin autoimmune syndrome (IAS) is characterized by spontaneous hypoglycemia, extremely high serum insulin levels, and high titers of autoantibodies against endogenous insulin, in the absence of exogenous insulin injection. IAS often occurs following exposure to sulfhydryl-containing drugs, including alpha-lipoic acid (ALA). A 30-year-old woman without diabetes visited our outpatient clinic with recurrent hypoglycemia. She had been taken ALA for weight reduction since 3 weeks ago. Further hypoglycemia work up revealed very high insulin levels, C-Peptide levels and positive insulin antibodies. And conventional imaging examinations were negative for insulinoma or other pancreatic tumors. Finally, the diagnosis of Insulin autoimmune syndrome (IAS) was made. Following the cessation of ALA, hypoglycemia improved, with no medication, and the patient experienced no further hypoglycemic attacks over the next month. The use of ALA as a nutritional supplement is increasing. We report a case of IAS associated with ALA in a non-diabetic patient.

Development of Volume Modified Sorption Model and Prediction for Volumetric Strain of Coal Matrix (흡착에 의한 석탄암체의 부피변화가 고려된 흡착모델 개선 및 부피변형률 예측)

  • Kim, Sang-Jin;Sung, Won-Mo
    • Journal of the Korean Institute of Gas
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    • v.19 no.2
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    • pp.37-44
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    • 2015
  • We proposed the improved Langmuir adsorption relations considering volume change effect of coal matrix during primary production of CBM and Enhanced-CBM with injection of carbon dioxide or CCS in coalseam but also volumetric strain. To verify this model, experimental data of pure gas adsorption such as $CO_2$, $CH_4$, and $N_2$ on coals were used to compare conventional Langmuir model with this model. From the results, we obtained that the larger adsorption capacity of coal and the higher adsorption affinity of gas, the larger error occur with Langmuir model. Using this model, however, we found not only substantially better fit in all condition but also reasonable volumetric strain of the coal matrix. We also applied this volume modified pure gas adsorption model to the IAS model to describe gas adsorption and volumetric strain for mixed gas. This modified-IAS model fitting experimental data by Hall et al(1994) improved accuracy of mixed gas adsorption calculation compared with conventional model.

WSN Lifetime Analysis: Intelligent UAV and Arc Selection Algorithm for Energy Conservation in Isolated Wireless Sensor Networks

  • Perumal, P.Shunmuga;Uthariaraj, V.Rhymend;Christo, V.R.Elgin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.3
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    • pp.901-920
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    • 2015
  • Wireless Sensor Networks (WSNs) are widely used in geographically isolated applications like military border area monitoring, battle field surveillance, forest fire detection systems, etc. Uninterrupted power supply is not possible in isolated locations and hence sensor nodes live on their own battery power. Localization of sensor nodes in isolated locations is important to identify the location of event for further actions. Existing localization algorithms consume more energy at sensor nodes for computation and communication thereby reduce the lifetime of entire WSNs. Existing approaches also suffer with less localization coverage and localization accuracy. The objective of the proposed work is to increase the lifetime of WSNs while increasing the localization coverage and localization accuracy. A novel intelligent unmanned aerial vehicle anchor node (IUAN) is proposed to reduce the communication cost at sensor nodes during localization. Further, the localization computation cost is reduced at each sensor node by the proposed intelligent arc selection (IAS) algorithm. IUANs construct the location-distance messages (LDMs) for sensor nodes deployed in isolated locations and reach the Control Station (CS). Further, the CS aggregates the LDMs from different IUANs and computes the position of sensor nodes using IAS algorithm. The life time of WSN is analyzed in this paper to prove the efficiency of the proposed localization approach. The proposed localization approach considerably extends the lifetime of WSNs, localization coverage and localization accuracy in isolated environments.

Estimation of Rainfall Erosivity in North Korea using Modified Institute of Agricultural Sciences (수정 IAS 지수를 이용한 북한지역의 강우침식인자 추정)

  • Lee, Joon-Hak;Heo, Jun-Haeng
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.6
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    • pp.1004-1009
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    • 2011
  • Soil erosion in North Korea has been continued to accelerate by deterioration of topographical conditions. However, few studies have been conducted to predict the amount of soil loss in North Korea due to limited data so far. Rainfall erosivity is an important factor to predict the amount of long-term annual soil loss by USLE (universal soil loss equation). The purpose of this study is to investigate rainfall erosivity, which presented the potential risk of soil erosion by water, in North Korea. Annual rainfall erosivities for 27 stations in North Korea for 1983~2010 were calculated using regression models based on modified Institute of Agricultural Sciences (IAS) index in this study. The result showed that annual average rainfall erosivity in North Korea ranged from 2,249 to 7,526 and averaged value was $4,947MJmm\;ha^{-1}\;hr^{-1}\;yr^{-1}$, which corresponded to about 70% of annual average rainfall erosivity in South Korea. The finding was that the potential risk of soil erosion in North Korea has been accelerated by the increase of rainfall erosivity since the late 1990s.

Diversity and distribution of invasive alien plant species along elevation gradient in Makawanpur district, central Nepal

  • Dipesh Karki;Bijay Pandeya;Balkrishna Ghimire
    • Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.75-84
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    • 2023
  • Background: Knowledge of the spatial trends of plant invasions in different habitats is essential for a better understanding of the process of these invasions. We examined the variation in invasive alien plant species (IAS) richness and composition at two spatial scales defined by elevation and habitat types (roadside, forest, and cultivated lands) in the Makawanpur district of Nepal. Following an elevation gradient ranging from 500 to 2,400 m asl along a mountain road, plant species cover was recorded within sample plots of size 10 m × 5 m. Systematic random sampling was adopted in every 100 m elevation intervals on three habitat types. Results: Altogether 18 invasive alien plants belonging to eight families were recorded within 60 plots, of which 14 species (representing 80%) were from tropical North and South America. The most common plants by their frequency were Ageratina adenophora, Chromolaena odorata, Bidens pilosa, Lantana camara, and Parthenium hysterophorus. We found a significant relationship between species composition and elevation in the study area. Low-elevation regions had a higher number of alien species as compared to high-elevation regions within different habitat types. Conclusions: The species richness and density of IAS were higher in the road site followed by the cultivated land and forest sites. This pattern occurred throughout the elevation range and habitats. IAS were found mostly in the open land with high sunlight availability. Information from such scientific assessment of invasive alien plants will assist in developing appropriate management plans in the Makawanpur district.

Distribution of Invasive Alien Species in Korean Croplands (농경지 내 생태계교란식물의 분포)

  • Kim, Jin-Won;Lee, In-Yong;Lee, Jeongran
    • Weed & Turfgrass Science
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    • v.6 no.2
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    • pp.117-123
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    • 2017
  • Invasive alien species (IAS) can affect agricultural ecosystem negatively and critically. The geographical distributions of nine IAS plants in Korean orchards and uplands were investigated. Ambrosia artemisiifolia distributed widely in Korean peninsula and Ambrosia trifida distributed intensively in Gyeonggi-do. Aster pilosus distributed in Gyeonggi-Gangwon region and Lactuca scariola distributed linear region from the north-western to south-eastern part of Korea. Hypochaeris radicata distributed mainly in Jeju-do and Solanum carolinense distributed in eastern Gyeonggi-do. Rumex acetosella and Sicyos angulatus sporadically occurred in Korean croplands and Eupatorium rugosum was found in one region only. The distribution of IAS plants in croplands was very similar to that in non-croplands suggesting that ecological position of arable lands is not different from that of non-arable lands. Therefore, IAS plants in the croplands should be managed for not only prevention of yield reduction, but also protection or maintenance of original ecosystem. Development of management methods apposite to current Korean status are required to control IAS plants in croplands.

A Fast Integer Ambiguity Resolution Method For Precise Positioning On- The-Fly (OTF 정밀측위를 위한 신속한 미지정수 결정방법)

  • 이대규;성태경
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.5
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    • pp.458-463
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    • 2004
  • This paper presents a fast IA(integer ambiguity) resolution method that determines the IA within short epochs with guaranteed reliability. Based on the fact that the search volume and the cost function are influenced by the selection of primary IAs in the plane intersection method, an IA resolution method is proposed that evaluates IA candidates repeatedly in an epoch with different combinations of primary IAs. In order to guarantee the reliability of the resolved IA with a certain probability, an inequality condition for selecting differencing operator is derived. Experiment results show that the proposed method consistently provides the true IA estimates within short time.

현장공기분사공정법(IAS)을 이용한 공기 영향반경과 흐름 양상 연구

  • 이준호;박갑성
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.213-217
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    • 2004
  • Laboratory scale study for an area of influence and flowing aspect of groundwater saturated zone was conducted for three sediment grains. On the AMG(Average Modal diameter Grains) 0.34, 1.38, 3.89mm diameter samples, the affected area of the aquifer were 15.2, 37.0, 30.0%/m2 each. Air flow for AMG 0.34mm diameter grain size provides indication of pattern of channelized air flow in saturated zone and expansion state in above saturated zone. For AMG of 1.38, 3.89mm diameter grains, air flow are pervasive air flow, forming a symmetrical cone of influence around the injection point. And also AMG 1.38, 3.89mm diameter samples show onset of collapse and approach to steady state in above saturated zone, respectively. In this study, optimal sites for in situ air sparging, may be grain diameters between about AMC 1.5~2.5mm diameter.

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