• Title/Summary/Keyword: deterioration point

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Efficient Clock Synchronization Schemes for Enhancing Error Performance of OFDM Wireless Multimedia Communication Systems (OFDM 무선 멀티미디어 통신 시스템의 오율성능 향상을 위한 효율적인 샘플링 클럭 동기방식)

  • 김동옥;윤종호
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.1
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    • pp.69-74
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    • 2003
  • In this paper, we propose the synchronization recovery algorithm which is suitable to wireless Multimedia of wireless channel situation which is being used OFDM signaling method. The basic of the suggested clock synchronization. restoration Algorithm is to getting the shock response of channel or getting the multipath strength profile through IFTT after the getting the frequency, response of deducted channel from channel deducted of receiver and to trace the location in the channel energy concentrated area of timing area. And it also analysis the start point of 64-QAM and 16-QAM if the sampling clock offset has the sample of ${\pm}$ 1-3, and we identified the occurance of performance deterioration when occures more than 2 samples of offset to compare with star point and BER performance in optimum sampling point result of BER performance checking, and we know that the recovery algorithm proposed algorithm also provide excellent synchronization characteries under frequency, selecting fading channel as result of simulation.

Identifying dominant parameters of storm-sewer-overflows in seperate sewer system (강우시 도시배수구역의 유출특성 지배인자 분석)

  • Jung, Si Mon;Park, In Hyeok;Ha, Sung Ryong
    • Journal of Wetlands Research
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    • v.10 no.2
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    • pp.105-114
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    • 2008
  • Growth in population and urbanization has progressively increased the loadings of pollutants from non-point sources as well as point sources. Separated sewer overflows(SSO) have been considered as a major cause of water-quality deterioration of natural water-courses in the vicinity of the heavily urbanized areas. The factors defining the magnitude and occurrence of SSO are site-specific. It is important to know exact properties of pollutants contained in SSO to address water quality impacts that are caused by SSO inputs to the receiving waters. Site and event parameters found to have significant influences on urban runoff pollutant EMCs include total event rainfall, antecedent dry period, rainfall intensity. In this study, a field survey was carried out in some selected areas of Cheongju city. Literature from previous similar studies was consulted and some important factors affecting the runoff characteristics of urban drainage areas were analyzed for some selected survey points. It was found that the factors most affecting BOD are the number of dry days prior to rainfall and the intensity of the rainfall. The factor most affecting CODcr is the number of dry days prior to rainfall. The factors most affecting SS are the amount of rainfall and the number of dry days prior to rainfall. The factor most affecting TN is the amount of rainfall. The factor most affecting TP is the amount of rainfall and the number of dry days prior to rainfall.

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Prospective of Sustainable Agriculture in Korea (친환경 농업기술의 발전방향)

  • 류순호
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1999.06a
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    • pp.137-159
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    • 1999
  • Over the last three decades, Korean farming system has been directed to maximum agricultural production and to increase farmer's income through adoption of high-yielding crop varieties and high input of agrochemicals . These farming practices have resulted in problems of water-quality deterioration, soil degradation , and food safety. At present, over 40 million tones of animal waste are bing produced annually, which amounts to disposing the waste at the annual rate of 20 tones per ha in the total area of farming land in Korea. Nearly a half of total available water resources is used as irrigation water predominantly for rice paddy field. Thus, non-point source contamination of the water resources has been linked to agriculture across the nation. However, the extent to which agriculture contributes to the water quality is not fully known. Recently, Korean government provided various institutional measures to reduce the negative impacts of agricultural practices on the environ ental quality, and the Agricultural Environment Act was also passed by the legislature in 1998 and became effective January 1999. This Act does not cover the broad spectrum of the sustainable agriculture ; thus, the limited incentives within this Act are arguably ineffective to control the non-point source pollution. Recently new bulk blending of fertilizers(BB fertilizer) are bing produced (100, 000 tones in 1998) with Government subsidies. The BB fertilizers are to balance N-P-K ratio in the soils . Although the use of the BB fertilizers are encouraged with Government subsidies, non-point source pollution is still serious and will become worse. Precision farming is regarded as a new means for sustainable agriculture. It is a new technology that modifies the existing techniques and incorporates new one such as GIS, GPS , differential applicator to produce a new set of tools for the farmer to use. Precision farming, however, has constraints for individual farming practices. For exam le , farm size or parcel unit of each farmer is too small to adopt the precision agriculture on farmhouse-hold bases and farmer's ability to adopt the new technology is limited. However, it would be appropriate to establish local or regional cooperatives to operate such a precision farming system. It is recommended that Government provide sufficient incentives to help establish local and/or regional cooperatives.

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A research on the $CO_2$ Peak Point Control according to Ventilation Frequency during Sleeping (취침 시 환기횟수에 따른 $CO_2$ 피크치 제어에 관한 연구)

  • Won, You-Mi;Kim, Dae-Seung;Lee, Woo-Jin;Kim, Dong-Gyu;Kim, Se-Hwan
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.731-736
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    • 2008
  • There was in a building and with the technical advance for a energy saving the secret efficiency of the building improved together and continuously was come. The indoor air environment brought about the deterioration which is remarkable because of it. But time of most the indoor air environmental matter is one in the element which healthily affects biggest in the moderns who lives from the interior space. Today the plan for the air environmental maintenance which dwelling space is appropriate is demanded, is the actual condition where the method of the ventilation control which is energy saving and efficient is necessary. From the research which it sees, number of ventilation 0.7 time of the aeration which is a domestic legal baseline is excessive is judged from the research which sees, The sleep hour assumes it stays most long the hour when, number of ventilation 0 time 0.1 times 0.4 times $CO_2$ consistency measurements and analyzes number of ventilation conclusive escape. And $CO_2$ peak point control leads it decides a data, effective and it talks an energy saving circulation control method and it does to sleep.

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Performance Analysis of a Synchronization Algorithm For in Multimedia Wireless Channel (멀티미디어 무선채널 환경에서 동기 알고리즘 성능분석)

  • 김동욱;윤종호
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.880-883
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    • 2002
  • In this paper, we propose the synchronization recovery algorithm which is suitable to wireless multimedia of wireless channel situation which is being used OFDM signaling method. The basic of the suggested clock synchronization. restoration Algorithm is to getting the shock response of channel or getting the multipath strength profile through IFFT after the getting the frequency, response of deducted channel from channel deductor of receiver and to trace the location in the channel energy concentrated area of timing area. And it also analysis the start point of 64-QAM and 16-QAM if the sampling clock offset has the sample of $\pm$1-3, and we identified the occurance of performance deterioration when occures more than 2 samples of offset to compare with star point and BER performance in optimum sampling point result of BER performance checking, and we know that the recovery algorithm proposed algorithm also provide excellent synchronization characteries under frequency, selecting fading channel as result of simulation.

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Design of Face Recognition Algorithm based Optimized pRBFNNs Using Three-dimensional Scanner (최적 pRBFNNs 패턴분류기 기반 3차원 스캐너를 이용한 얼굴인식 알고리즘 설계)

  • Ma, Chang-Min;Yoo, Sung-Hoon;Oh, Sung-Kwun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.6
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    • pp.748-753
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    • 2012
  • In this paper, Face recognition algorithm is designed based on optimized pRBFNNs pattern classifier using three-dimensional scanner. Generally two-dimensional image-based face recognition system enables us to extract the facial features using gray-level of images. The environmental variation parameters such as natural sunlight, artificial light and face pose lead to the deterioration of the performance of the system. In this paper, the proposed face recognition algorithm is designed by using three-dimensional scanner to overcome the drawback of two-dimensional face recognition system. First face shape is scanned using three-dimensional scanner and then the pose of scanned face is converted to front image through pose compensation process. Secondly, data with face depth is extracted using point signature method. Finally, the recognition performance is confirmed by using the optimized pRBFNNs for solving high-dimensional pattern recognition problems.

Application of Acoustic Emission for Assessing Deterioration in Reinforced Concrete Beams (철근 콘크리트 빔의 노화도 평가를 위한 음향방출 기술의 응용)

  • Yoon, Dong-Jin;Park, Phi-Lip;Lee, Seung-Seok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.20 no.4
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    • pp.276-284
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    • 2000
  • The acoustic emission (AE) behavior of reinforced concrete beams tested under flexural loading was investigated to characterize and identify the source of damage. This research was aimed at identifying the characteristic AE response associated with micro-crack development, localized crack propagation, corrosion, and debonding of the reinforcing steel. Concrete beams were prepared to isolate the damage mechanisms by using plain, notched-plain, reinforced, and corroded-reinforced specimens. The beams were tested using four-point cyclic step-loading. The AE response was analyzed to obtain key parameters such as the time history of AE events, the total number and rate of AE events, and the characteristic features of the waveform. Initial analysis of the AE signal has shown that a clear difference in the AE response is observed depending on the source of the damage. The Felicity ratio exhibited a correlation with the overall damage level, while the number of AE events during unloading can be an effective criterion to estimate the level of corrosion distress in reinforced concrete structures. Consequently, AE measurement characterization appears to provide a promising approach for estimating the level of deterioration in reinforced concrete structure.

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Drainage and Treatment Characteristics of Runoff by Media (여재에 따른 도로면 유출수의 배수 및 처리특성)

  • Kim, Seog-gu;Yun, Sang-Ieen;Kim, Young-im;Lee, Yong-jae;Kim, Ree-ho;Kim, Jong-oh
    • Journal of Korean Society on Water Environment
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    • v.20 no.5
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    • pp.500-505
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    • 2004
  • While more attention has been paid in recent years to urban point source pollution control, no considerable measures have been taken to control urban non-point source pollution. Contaminants from non-point sources deposited on urban impermeable surfaces such as road and highway are easily released to the public waters by rainfall, leading to the deterioration in water quality in urban area. The present study investigated a system using filter media to reduce the level of contamination in urban road runoff. Three different media, designated as J-P (polypropylene, blowing type), B-P (polypropylene, fiber type), and P-F (Polyvinyl alcohol, cube and sheet type) were evaluated on the basis of pollutant removal efficiency as well as hydraulic property. Experiments were peformed using a 1/4-scale treatment unit at various pollutant roading and rainfall intensity with real rainwater runoff collected from road surfaces. The results at different rainfall intensities shows that the medium J-P is superior to the other media for water permeability. J-P was not blocked at 10 mm/hr rainfall and its permeability was stable. On the other hand, B-P and P-F resulted in substantial overflow ratio even at I mm/hr rainfall intensity. Comparing treatment efficiencies for suspended solids, all media showed similar removal ranged from 91 % to 95%. However, J-P seems to be better than the other media considering its higher water permeability. J-P and P-F, both hydrophobic, yielded over 76% of heavy metal removal. But, the hydrophilic media B-P showed much smaller removal ranging from 26% to 47%. This indicates that J-P and P-F are beneficial to remove heavy metal due to their hydrophobic property. The treatment efficiencies over PAHs (poly aromatic hydrocarbons) showed the similar removal efficiency ranging from 66% to 97% for all three media.

Improvement Effect of Water Quality along the Water Discharged Area by Water Dispersion from the Sewage Disposal Plant (하수처리장 분산방류에 의한 방류수역의 수질개선효과)

  • Kim, Dong-Soo;Park, Jong-Tae;Kim, Yong-Gu;Park, Sung-Chun
    • Journal of Environmental Science International
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    • v.17 no.1
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    • pp.113-118
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    • 2008
  • [ $6{\sim}13mg/L$ ] base water concentration on monthly BOD has been kept at the Geukrak bridge point for this research target and it indicates the water quality under the existed rank. Due to this present condition of water quality, the demage of ecology from the upper stream to the lower one of the bridge could be conjectured. Moreover, nonstructural extinction of the ecology seems to have gotten worse between both the streams of Yeoungsan River. On this research, eco-corridor between the upper stream and the lower stream of the river should be ensured, the ecological demage needs to be cut off, a dispersed discharge method which the existed method of the 1st sewage plant in Gwangju was enhanced to should be inducted for the procuring of various water ecosystem, and the conditions by the scenario suggested from this research could be applied to a water quality model. then, analysis the improvement effect of the water quality adjacent the river. From the test result, Case3-Type1 scenario is thought to be the best one. From the test result with Case3-Type1 when the concentrated discharge was never done, 0.07 mg/L of BOD concentration was increased at the lower stream where Yeoungbon B point (Haksan Bridge) is but the water improvement effect of $0.24{\sim}2.87mg/L$ is thought to have been done at the area of water deterioration.

Results of Thumb-pulp Loss Reconstruction with a Heterodigital Neurovascular Island Flap Using a Nerve Disconnecting-Reconnecting Technique (무지 피부 결손에 신경 분리-문합을 이용한 이종 수지 신경혈관 도서형 유경 피판술의 결과)

  • Chung, Duke-Whan;Kim, Gi-Bong
    • Archives of Reconstructive Microsurgery
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    • v.10 no.2
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    • pp.169-174
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    • 2001
  • Purpose : The problems of late deterioration of sensation and a double sensibility phenomenon are a known deficiency of the original neurovascular island flap. To eliminate this problems, the authors was performed to assess the results of Thumb-pulp loss reconstruction with a heterodigital neurovascular island Flap Using a Nerve Disconnecting-Reconnecting Technique Material and Methods : Between July. 1987 and November. 2000, we have used a disconnecting-reconnecting technique for heterodigital island flaps in which divided nerve of the transferred island flap is sutured to original nerve of the thumb in 9 patients. 9 patients with a mean follow-up period of 3.6 years were examined, while 7 patients were follow-up for 2years or more. Evaluation of results was based on flap quality, donor site quality, classic two-point sensory discrimination(2PD), and location of sensation(double sensibility), donor site cold intolerance, neuroma formation, scar contractures, total active movement(TAM) of the thumb and donor digit and subjective results and objective results. Results : The two-point discrimination was average 6.7 mm. Donor site paresthesia was observed more frequently in a short postoperative period. Sensation was referred to the thumb in all cases and the recovery occurred over a period of a two months. There were no flap complication or failures and the length of the thumb tip was preserved in all cases. Conclusion : This technique was found to provide well-vascularized pulp of the thumb with proper cortical representation in one operative stage.

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