• Title/Summary/Keyword: AoA

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Improvement of the Advanced Treatment for Nitrogen Removal of Acrylic Fiber Wastewater (아크릴섬유 폐수의 생물학적 질소제거공정의 개선)

  • Lee, Chan-Won;Cho, In-Sung;Lim, Kyeong-Won
    • Journal of Environmental Science International
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    • v.15 no.5
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    • pp.439-446
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    • 2006
  • The effluent discharge standards of industrial wastewater has become more stringent since 2003. Many industrial wastewater treatment plants has been upgraded to advanced treatment facilities. There are high concentrations of nitrate(>200 mg/L) and ammonium(>50 mg/L) nitrogen in the acrylic fiber wastewater of H textile Co. Wastewater from acrylic fiber industry containing acrylonitrile, which may affect the subsequent biological treatment process. Manufacturing of acrylic fiber also produces shock loadings. Excessive acrylonitrile and polymer debris produced in the polymerization process was screened, coagulated with CaO and settled down. A preaeration system was added to treat this high pH effluent to remove volatile organic compound and ammonia nitrogen by the air stripping effect. it was found that nitrification rate was not sufficient in the Anoxic/Oxic(AO) process. One denitrification tank was converted to nitrification reactor to extend HRT of nitrification. Nitrification rate of ammonia nitrogen was promoted from 32% to 67% by this modification and effluent nitrogen concentration was well satisfied with the effluent standards since then.

Comparative Study of Asian Ethnic Dresses(PartI) (아시아 전통문화양식의 전개과정에 관한 비교 문화연구(제 1보)-근대 동남아시아 민속복식을 중심으로-)

  • 유혜경;홍나영;이주현;김찬주
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.8
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    • pp.1043-1051
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    • 1998
  • The main purpose of this paper was to investigate how ethnic dresses are adopted into modern fashion designs. This research focuses on Japan and Vietnam as a part of an ongoing larger project which examines ethnic dresses of five Asian countries. Fashion designs with influences of Japanese and Vietnames ethnic dresses were anlayzed in order to explore how ethnic dresses coexist with "world fashion" in contemporary society. Eight fashion magazines were examined and the pictures of eigher Japanese or Vietnamese influences were identified. A total of 66 pictures for Japan and 5 for Vietnam were analyzed in terms of eleven characteristics on zero-to-three scales according to authenticity of each characteristic. The characteristics included shape, item, silhouette, color, material, textile print, decorative details, method of dressing, accessories, hairstyle and make-up. The results showed that textile prints and color of Japanese ethnic dresses, and item, silhouette and hat of Vietnamese dresses were most frequently adopted in modern fashion designs. These suggested that fashion world adopts the most distinctive and easy-to-copy characteristics of the ethnic dresses when the designers wanted to incorporate the styles of ethnic dresses.c dresses.

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Properties of Carbon Black/SBR Rubber Composites Filled by Surface Modified Carbon Blacks

  • Dai, Shuang-Ye;Ao, Ge-You;Kim, Myung-Soo
    • Carbon letters
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    • v.8 no.2
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    • pp.115-119
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    • 2007
  • Properties of carbon blacks and carbon black/SBR rubber composites filled by surface modified carbon blacks were examined. Although the specific surface area of carbon blacks increased after the surface modifications with heat, acid, and base, there were no obvious changes in resistivity. The composites filled by heat treated carbon blacks showed a higher tensile strength and elongation than those filled by raw blacks. The acid and base treated carbon blacks filled composites also showed higher tensile strength but similar elongation values with those filled by raw blacks. With increasing loading ratio, both tensile strength and elongation increased, and appeared a maximum value at 30-40 phr. Modulus at 300% strain remained increasing with further loading of carbon blacks. At the same loading, the heat treated black filled composites showed similar modulus values with composites filled by raw blacks but for base and acid treated black filled composites much higher values were obtained. After the surface modification, the functional groups which played an important role in reinforcement action were changed.

Correlation Analysis Between the Variation of Net Surface Heat Flux Around the East Asian Seas and the Air T emperature and Precipitation Over the Korean Peninsula (동아시아 해역의 표층 순열속 변동과 한반도 기온 및 강수량 변동의 상관성 분석)

  • Lee, Seok-Joon;Chang, You-Soon
    • Ocean and Polar Research
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    • v.43 no.1
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    • pp.15-30
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    • 2021
  • In this study, using 16 ORA-IP (Ocean Reanalysis Intercomparison Project) data, we investigated spatial and temporal changes of net surface heat flux in the East Asian seas and presented a new ensemble net surface heat flux index. The ensemble net surface heat flux index is produced considering the data distribution and the standard deviation of each ORA-IP. From the correlation analysis with air temperature averaged over the Korean Peninsula, ensemble net heat flux around the Korea Strait shows the highest correlation (0.731) with a 3 month time lag. For the correlation study regarding precipitation over the Korean Peninsula, it also shows significant correlation especially in winter and spring seasons. Similar results are also found in comparison with climate indices (AO, PDO, and NINO3.4), but ensemble net surface heat flux data in winter season reveals the strongest correlation patterns especially with winter temperature and spring precipitation.

Bivariate Oscillation Model for Surrogating Climate Change Scenarios in the LCRR basin

  • Lee, Taesam;Ouarda, Taha;Ahn, Yujin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2021.06a
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    • pp.69-69
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    • 2021
  • From the unprecedented 2011 spring flood, the residens reside by Lake Champlain and Richelieu River encountered enormous damages. The International Joint Committee (IJC) released the Lake Champlain-Richelieu River (LCRR) Plan of Study (PoS). One of the major tasks for the PoS is to investigate the possible scenarios that might happen in the LCRR basin based on the stochastic simulation of the Net Basin Supplies that calculates the amount of flow into the lake and the river. Therefore, the current study proposed a novel apporach that simulate the annual NBS teleconnecting the climate index. The proposed model employed the bivariate empirical decomposition to contamporaneously model the long-term evolution of nonstationary oscillation embeded in the annual NBS and the climate signal (here, Artic Oscillation: AO). In order to represent the variational behavior of NBS correlation structure along with the temporal revolution of the climate index, a new nonstationary parameterization concept is proposed. The results indicate that the proposed model is superior performance in preserving long and short temporal correlation. It can even preserve the hurst coefficient better than any other tested models.

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Enhance photoelectric efficiency of PV by optical-thermal management of nanofilm reflector

  • Liang, Huaxu;Wang, Baisheng;Su, Ronghua;Zhang, Ao;Wang, Fuqiang;Shuai, Yong
    • Advances in nano research
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    • v.13 no.5
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    • pp.475-485
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    • 2022
  • Crystalline silicon photovoltaic cells have advantages of zero pollution, large scale and high reliability. A major challenge is that sunlight wavelength with photon energy lower than semiconductor band gap is converted into heat and increase its temperature and reduce its conversion efficiency. Traditional cooling PV method is using water flowing below the modules to cool down PV temperature. In this paper, the idea is proposed to reduce the temperature of the module and improve the energy conversion efficiency of the module through the modulation of the solar spectrum. A spectrally selective nanofilm reflector located directly on the surface of PV is designed, which can reflect sunlight wavelength with low photon energy, and even enhance absorption of sunlight wavelength with high photon energy. The results indicate that nanofilm reflector can reduce spectral reflectivity integral from 9.0% to 6.93% in 400~1100 nm wavelength range, and improve spectral reflectivity integral from 23.1% to 78.34% in long wavelength range. The nanofilm reflector can reduce temperature of PV by 4.51℃ and relatively improved energy conversion efficiency of PV by 1.25% when solar irradiance is 1000 W/m2. Furthermore, the nanofilm reflector is insensitive in sunlight's angle and polarization state, and be suitable for high irradiance environment.

A Study on Sensor Collection Planning based on Target Scheduling and Deviation Correction for Strategic UAV Surveillance and Reconnaissance (전략급 무인기의 감시정찰을 위한 표적 스케줄링 및 편차 보정 기반 촬영계획 자동화 기술 연구)

  • Junghee Cho;Yunjeong Choi;Hayrim Lee;Soyoung Jeong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.27 no.2
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    • pp.177-188
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    • 2024
  • The strategic UAV for theater level ISR(Intelligence, Surveillance and Reconnaissance) mission typically has numerous ground targets over area of responsibility(AOR) or area of operation(AO). It is necessary to automatically incorporate these multitude of ground targets into mission planning process in order to collect ISR images before actual flight mission. In addition, weather information such as wind direction and/or velocity may have significant impacts on the qualities of collected sensor images, especially in SAR(Synthetic Aperture Radar) images. Thus weather factors in the operation altitude should also be considered in the mission planning stage. In this study, we propose a novel mission planning scheme based on target scheduling and deviation correction method incorporating weather factors.

Optimization for Relay-Assisted Broadband Power Line Communication Systems with QoS Requirements Under Time-varying Channel Conditions

  • Wu, Xiaolin;Zhu, Bin;Wang, Yang;Rong, Yue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.10
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    • pp.4865-4886
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    • 2017
  • The user experience of practical indoor power line communication (PLC) applications is greatly affected by the system quality-of-service (QoS) criteria. With a general broadcast-and-multi-access (BMA) relay scheme, in this work we investigate the joint source and relay power optimization of the amplify-and-forward (AF) relay systems used under indoor broad-band PLC environments. To achieve both time diversity and spatial diversity from the relay-involved PLC channel, which is time-varying in nature, the source node has been configured to transmit an identical message twice in the first and second signalling phase, respectively. The QoS constrained power allocation problem is not convex, which makes the global optimal solution is computationally intractable. To solve this problem, an alternating optimization (AO) method has been adopted and decomposes this problem into three convex/quasi-convex sub-problems. Simulation results show the fast convergence and short delay of the proposed algorithm under realistic relay-involved PLC channels. Compared with the two-hop and broadcast-and-forward (BF) relay systems, the proposed general relay system meets the same QoS requirement with less network power assumption.

The Development of High Speed Wavefront Sensor for Diagnosis of Beam Quality of He-Ne Laser (He-Ne 레이저 빔 품질 진단용 고속파면센서 개발)

  • Lee, Young-Cheol;Lee, Jae-Il;Kang, Eung-Cheol
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.4
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    • pp.160-167
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    • 2007
  • In this paper, we presented the development results of high speed wavefront sensor which is used in diagnosing the beam quality of He-Ne laser for adaptive optics system. The beam quality information of laser in AO system is necessarily required for diagnosing the optical components or correcting the distorted wavefront afterward. According to system requirements, normally, it is requested that there are high precision of measurement and real time processing speed. The developed wavefront sensor in this paper achieved maximum 30Hz of measurement rate and ${\lambda}/20(\;{@}\;{\lambda}=0.6328{\mu}m)$ of measurement precision in RMS. We also applied the developed into an experimental adaptive system and verified the performance of it by correcting the aberrated wavefront with a rate of 30Hz and $\lambda$/20 precision using the combination of the developed and PID control algorithm.

ATF3 Activates Stat3 Phosphorylation through Inhibition of p53 Expression in Skin Cancer Cells

  • Hao, Zhen-Feng;Ao, Jun-Hong;Zhang, Jie;Su, You-Ming;Yang, Rong-Ya
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7439-7444
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    • 2013
  • Aim: ATF3, a member of the ATF/CREB family of transcription factors, has been found to be selectively induced by calcineurin/NFAT inhibition and to enhance keratinocyte tumor formation, although the precise role of ATF3 in human skin cancer and possible mechanisms remain unknown. Methods: In this study, clinical analysis of 30 skin cancer patients and 30 normal donors revealed that ATF3 was accumulated in skin cancer tissues. Functional assays demonstrated that ATF3 significantly promoted skin cancer cell proliferation. Results: Mechanically, ATF3 activated Stat3 phosphorylation in skin cancer cell through regulation of p53 expression. Moreover, the promotion effect of ATF3 on skin cancer cell proliferation was dependent on the p53-Stat3 signaling cascade. Conclusion: Together, the results indicate that ATF3 might promote skin cancer cell proliferation and enhance skin keratinocyte tumor development through inhibiting p53 expression and then activating Stat3 phosphorylation.