• Title/Summary/Keyword: demand control

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A embodiment of the interface module for feed back control between auto-pilot with water-jet system (오토파일럿과 워터젯시스템의 피드백 제어계 인터페이스 모듈의 구현)

  • Oh, Jin-Seong;Choi, Jo-Cheon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.1108-1111
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    • 2009
  • Auto Pilot is the system which move automatically the vessel through locating operation mode to automatic after entering operating course using a electronic chart or plotter. And water jet is the a propulsion system that make a power to push the vessel through spouting the accelerated water which is absorbed by the hole in the bottom of vessel. The water jet receive the effect of the depth of water lowly, it's acceleration efficiency is higher under high speed and have an advantage on vibrating and floating sound, so it's demand is increasing as new propulsion system. However, the signal systems of auto pilot and water jet are different, we need the system to interface between each system. We designed the interface that efficiently digital feed back control embedded module between auto pilot and water jet system in this paper.

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The Decrease of Return Temperature by Improvement of the Consumer's Control System in District Heating (지역난방 열사용시설 자동제어시스템 개선을 통한 회수온도 저감 연구)

  • Ha, Seung-Kyu;Kim, Youn-Hong;Lee, Hoon
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.245-251
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    • 2006
  • The main idea of this study is to turn attention on the question of good cooling ability of customer substations in large district heating networks. The main reason for that is based on our experience that the optimization of district heating very often is directed toward production, whereas questions of optimal distribution are neglected if only the necessary load can be supplied and the customer's request for comfort is met. Our view is that low return temperature(operational temperature differences, ${\Delta}T$) in district heating systems is an Important feature for efficient net operation and gives both economic and operational benefits to the district heating supplier Furthermore, it is as well a prerequisite for meeting the customers demand for reliable supply of the heat load. However, in many practical cases we have seen that district heating return temperatures are higher than necessary. Hence, the aim of the study is to propose and verify a method for detection of the most critical consumers of the net and to identify the reasons for resulting high return temperature. From the results, temperature control system is presented as one of the most important reason of high return temperature in DH networks.

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Determinants of Sustainable Fashion Consumption in China - Based on the Theory of Planned Behavior - (중국소비자의 지속가능 패션 소비 결정요인 연구 - 계획된 행동이론을 중심으로 -)

  • HU, XINYU;Jeong, So Won;Kim, Eunhye;Lee, Jin-Hwa
    • Fashion & Textile Research Journal
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    • v.23 no.4
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    • pp.458-468
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    • 2021
  • In the context of Sustainable development, China, the world's second-largest apparel market, is also concerned about the environmental impact of fiber waste. Currently, there is a great interest in sustainable fashion in both supply and demand in China. Based on the theory of planned behavior(TPB), the determinants of sustainable fashion consumption(SFC) of Chinese consumers were evaluated in this study: man-nature orientation(MNO) and environmental knowledge(EK) as motivation and perceived online-store accessibility(POA) and perceived money availability(PMA) as barriers. Wenjuanxing, a Chinese professional survey collection agency, conducted an online survey of millennials in Shanghai, China. The final sample size for the survey was 215. Partial least squares structural equation modeling was employed to test the proposed hypotheses. The results indicated that attitudes, subjective norms, and perceived behavioral control significantly affected the purchase intention towards sustainable fashion products. MNO and EK influenced the attitude, whereas EK, POA, and PMA influenced perceived behavioral control. This study contributes to the TPB literature through the examination of four antecedents: MNO, EK, POA, and PMA. The findings provide valuable insights for retailers and markets based on the identification of the motivations and barriers that enhance the purchasing intention of Chinese millennials toward SFC.

The Effects of Brain-wave Biofeedback Training Nursing Intervention upon Self-regulation of Emotional Behavior Problem in Adolescents at School (뇌파 바이오피드백훈련 간호중재가 학교 청소년 정서행동문제 관심군의 자기조절에 미치는 효과)

  • Choi, Moon-Ji;Park, Wan-Ju
    • Research in Community and Public Health Nursing
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    • v.32 no.3
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    • pp.254-267
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    • 2021
  • Purpose: The purpose of this study was to identify the effects of brain-wave biofeedback training nursing intervention (NFT) upon enhancing self-regulation response in adolescence with emotional behavior problems in school. Methods: A quasi-experimental design was conducted. The participants were assigned to the experimental group (n=24) or the control group (n=24). The experimental group additionally received NFT. The NFT was conducted 10 sessions for 30 minutes per session with the band reward and inhibit training which matched their Quantitative Electroencephalography (QEEG), participant's demand and chief complaint. Data were collected with QEEG and heart rate variability (HRV) in physiological response, self-efficacy in cognitive response, depression in emotional response, impulsivity and delay gratification in behavioral response of self-regulation. Results: The general characteristics and the pre-test scores of two groups were all homogeneous. The experimental group was reported to be significantly higher in QEEG homeostasis, HRV homeostasis, self-efficacy, and delay gratification than the control group. The experimental group was reported to be significantly lower in depression and impulsivity. Conclusion: The results indicate that NFT using brain cognitive neuroscience approach is effective in enhancing self-regulation response. Therefore, this nursing intervention using brain cognitive neuroscience approach can be applied as an effective self-regulation nursing intervention for adolescents with emotional behavior problems in communities for adaptive life.

Ozone-produced Oxidants Improve Water Quality Parameters and Microbial Colony Counts in the Semi-Recirculating Aquaculture System for Olive Flounder Paralichthys olivaceus (반순환여과양식시스템에서 오존 유래 잔류산화물이 넙치(Paralichthys olivaceus) 사육수의 수질과 미생물에 미치는 영향)

  • Jung, Sangmyung;Park, Woogeun;Park, Seongdeok;Park, Jeonghwan;Kim, Jae-Won;Kim, Pyong-kih
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.54 no.5
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    • pp.751-760
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    • 2021
  • This study investigated the changes in water quality parameters and microbial colonies when ozone was applied to a semi-recirculating aquaculture system (semi-RAS) for the olive flounder Paralichthys olivaceus (500 g in average weight). Concentrations of ozone-produced oxidants (OPO) in rearing tanks were maintained at 0, 0.014, 0.025 mg/L as Cl2 for 26 days. Except total ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, phosphate phosphorus, chemical oxygen demand, and total suspended solids decreased significantly with increasing OPO concentration in daily and weekly monitoring (P<0.05). Colony forming unit (CFU) counts of heterotrophic marine bacteria decreased in an OPO concentration-dependent manner. Overall reduction rates of microbial colonies in the treatments were 80% higher than those of the control (P<0.05). During the experiment, the OPO concentration-driven ozonation was reliably practiced without any adverse effects on the animals cultured in semi-RAS. Considering the biohazard, operating cost, and stability of ozonation, an OPO concentration of 0.014 mg/L would be sufficient to control water quality parameters and microbial colonies in a semi-RAS.

The Interaction of Cognitive Interference, Standing Surface, and Fatigue on Lower Extremity Muscle Activity

  • Hill, Christopher M.;DeBusk, Hunter;Simpson, Jeffrey D.;Miller, Brandon L.;Knight, Adam C.;Garner, John C.;Wade, Chip;Chander, Harish
    • Safety and Health at Work
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    • v.10 no.3
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    • pp.321-326
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    • 2019
  • Background: Performing cognitive tasks and muscular fatigue have been shown to increase muscle activity of the lower extremity during quiet standing. A common intervention to reduce muscular fatigue is to provide a softer shoe-surface interface. However, little is known regarding how muscle activity is affected by softer shoe-surface interfaces during static standing. The purpose of this study was to assess lower extremity muscular activity during erect standing on three different standing surfaces, before and after an acute workload and during cognitive tasks. Methods: Surface electromyography was collected on ankle dorsiflexors and plantarflexors, and knee flexors and extensors of fifteen male participants. Dependent electromyography variables of mean, peak, root mean square, and cocontraction index were calculated and analyzed with a $2{\times}2{\times}3$ within-subject repeated measures analysis of variance. Results: Pre-workload muscle activity did not differ between surfaces and cognitive task conditions. However, greater muscle activity during post-workload balance assessment was found, specifically during the cognitive task. Cognitive task errors did not differ between surface and workload. Conclusions: The cognitive task after workload increased lower extremity muscular activity compared to quite standing, irrespective of the surface condition, suggesting an increased demand was placed on the postural control system as the result of both fatigue and cognitive task.

Packaging technology of fresh-cut produce (신선편의식품 포장기술)

  • Kim, Ji Gang
    • Food Science and Industry
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    • v.50 no.2
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    • pp.12-26
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    • 2017
  • Processing steps such as washing and cutting, involved in preparing fresh-cut produce causes tissue damage, leading to rapid quality deterioration. Major defects of fresh-cut produce are discoloration, softening, off-odor development, and microbial growth. Packaging of fresh-cut produce has been changed to reduce these quality problems. Flexible packaging film is widely used to pack fresh-cut produce. Vacuum packaging was the popular packaging method in the beginning of fresh-cut industry in Korea. Vacuum packaging creates high $CO_2$ and low $O_2$ levels to control browning of fresh-cut produce. However, these conditions induce some visual defects and off-odor development. Discoloration problem was also found when fresh-cut produce was packaged with conventional packaging film or plastic tray. Modified atmosphere (MA) packaging is effective for prolonging shelf-life of fresh-cut produce by decreasing $O_2$ and increasing $CO_2$ concentration in the package. Retail MA packaging using different oxygen transmission rate (OTR) film and micro-perforated film has started to be applied to fresh-cut produce in Korea. Proper MA package design that provides optimum range of $O_2$ and $CO_2$ partial pressures is one of the major challenges in the industry. An initial package flushing with $N_2$ or an low $O_2$/high $CO_2$ atmosphere is also used to more rapidly establish steady-state MA condition. Film OTR and $O_2$ flushing affects the fermentative volatile production, off-odor development, electrolyte leakage, discoloration, $CO_2$ injury, microbial population of fresh-cut produce. There is also a demand for convenient packaging to attract consumers. Rigid fresh-cut produce container for retail market has increased since the packaging provides excellent protection from physical damage during transport. Rigid tray used as actual serving vessel for the consumer is increasing in Korea. The tray with flexible lid to wrap or seal fresh-cut produce is more and more gaining popularity. Further practical technology to control quality change and microbial growth for each fresh-cut product has been studied since various fresh-cut items were required. The fresh-cut industry also focuses on searching for more convenient and environmentally friendly packaging.

Information Security Management System on Cloud Computing Service (클라우드 컴퓨팅 서비스에 관한 정보보호관리체계)

  • Shin, Kyoung-A;Lee, Sang-Jin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.1
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    • pp.155-167
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    • 2012
  • Cloud computing service is a next generation IT service which has pay-per-use billing model and supports elastically provisioning IT infra according to user demand. However it has many potential threats originating from outsourcing/supporting service structure that customers 'outsource' their own data and provider 'supports' infra, platform, application services, the complexity of applied technology, resource sharing and compliance with a law, etc. In activation of Cloud service, we need objective assessment standard to ensure safety and reliability which is one of the biggest obstacles to adopt cloud service. So far information security management system has been used as a security standard for a security management and IT operation within an organization. As for Cloud computing service it needs new security management and assessment different from those of the existing in-house IT environment. In this paper, to make a Information Security Management System considering cloud characteristics key components from threat management system are drawn and all control domain of existing information security management system as a control components are included. Especially we designed service security management to support service usage in an on-line self service environment and service contract and business status.

A Study on the Physical Modeling of the Shaft Generator and the Fuel Consumption Verification Simulation of a Tugboat using Simulink (Simulink를 이용한 터그보트의 샤프트제너레이터 물리모델링 및 연료소모율 검증 시뮬레이션에 관한 연구)

  • Kim, Sung-Dong;Kim, Nam-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.22 no.1
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    • pp.7-13
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    • 2021
  • In recent years, the importance of environmental regulations is increasing in the shipping industry, and the demands of the industry for this are rapidly increasing. Accordingly, the demand of ship owners is increasing as the shaft generator is a technology that responds to environmental regulations that can be applied to ships the fastest. The shaft generator is a device that can increase the fuel consumption rate of the main propulsion engine by installing an electric motor in the main propulsion engine and using it variably according to the load environment. It operates by the power of the motor at low speeds, and when a sudden load is required, the main propulsion engine and motor operate together, enabling efficient operation. In this paper, the diesel engine and shaft generator of a tug boat are modeled using MATLAB Simulink, and the fuel consumption rate is verified through simulation.

A NARX Dynamic Neural Network Platform for Small-Sat PDM (동적신경망 NARX 기반의 SAR 전력모듈 안전성 연구)

  • Lee, Hae-Jun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.6
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    • pp.809-817
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    • 2020
  • In the design and development process of Small-Sat power distribution and transmission module, the stability of dynamic resources was evaluated by a deep learning algorithm. The requirements for the stability evaluation consisted of the power distribution function of the power distribution module and demand module to the SAR radar in Small-Sat. To verify the performance of the switching power components constituting the power module PDM, the reliability was verified using a dynamic neural network. The adoption material of deep learning for reliability verification is the power distribution function of the payload to the power supplied from the small satellite main body. Modeling targets for verifying the performance of this function are output voltage (slew rate control), voltage error, and load power characteristics. First, to this end, the Coefficient Structure area was defined by modeling, and PCB modules were fabricated to compare stability and reliability. Second, Levenberg-Marquare based Two-Way NARX neural network Sigmoid Transfer was used as a deep learning algorithm.