• Title/Summary/Keyword: Heating source

Search Result 897, Processing Time 0.025 seconds

Implementation of Greenhouse Environmental Control Systems using Intelligence (지능을 이용한 온실 제어 시스템)

  • Yang, J.;Chung, C.D.;Hong, You-Sik;Ahn, B.I;Hwang, S.I.;Choi, Y.H.
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.49 no.2
    • /
    • pp.29-37
    • /
    • 2012
  • An experiment for an optimized automatic greenhouse environment in a flower farming greenhouse by building a ubiquitous sensor network with various sensors was conducted and the results were evaluated. And various culturing environmental information and data in the greenhouse were collected and analyzed. Then, the greenhouse was designed to maintain the best culturing environment on the basis of existing recommended optimized figures. By measuring the growth of the crops in the greenhouse, A system which controls facilities in the greenhouse to maintain the best culturing environment in accordance with change in the environment was analyzed.Computer simulation result proced that we discovered that controlling the facilities and the artificial light source increased production, enhanced quality, reduced labor and heating cost immensely. The experiment has proved that the u-flower farming system can maximize the income of farm families by sending warning messages to users of this system when weather suddenly changes so that users may cope with such changes and maintain the best culturing environment.

Development of Thermoluminescence and Optical Stimulated Luminescence Measurements System (열자극발광 및 광자극발광 측정장치의 개발)

  • Park, Chang-Young;Chung, Ki-Soo;Lee, Jong-Duk;Chang, In-Su;Lee, Jungil;Kim, Jang-Lyul
    • Journal of Radiation Protection and Research
    • /
    • v.40 no.1
    • /
    • pp.46-54
    • /
    • 2015
  • The thermoluminescence (TL) and optically stimulated luminescence (OSL) are commonly used to measure and record the expose of individuals to ionization radiation. Design and performance test results of a newly developed TL and OSL measurement system are presented in this paper. For this purpose, the temperature of the TL material can be controlled precisely in the range of $1{\sim}1.5^{\circ}C$ by using high-frequency (35 kHz) heating system. This high-frequency power supply was made of transformer with ferrite core. For optical stimulation, we have completed an optimal combination of the filters with the arrangement of GG420 filter for filtering the stimulating light source and a UG11 filter at the detecting window (PMT). By using a high luminance blue LED (Luxeon V), sufficient luminous intensity could be obtained for optical stimulation. By using various control boards, the TL/OSL reader device was successfully interfaced with a personal computer. A software based on LabView program (National Instruments, Inc.) was also developed to control the TL/OSL reader system. In this study, a multi-functional TL/OSL dosimeter was developed and the performance testing of the system was carried out to confirm its reliability and reproducibility.

Intelligent Tuning of the Two Degrees-of-Freedom Proportional-Integral-Derivative Controller On the Distributed Control System for Steam Temperature Control of Thermal Power Plant

  • Dong Hwa Kim;Won Pyo Hong;Seung Hack Lee
    • KIEE International Transaction on Systems and Control
    • /
    • v.2D no.2
    • /
    • pp.78-91
    • /
    • 2002
  • In the thermal power plant, there are six manipulated variables: main steam flow, feedwater flow, fuel flow, air flow, spray flow, and gas recirculation flow. There are five controlled variables: generator output, main steam pressure, main steam temperature, exhaust gas density, and reheater steam temperature. Therefore, the thermal power plant control system is a multinput and output system. In the control system, the main steam temperature is typically regulated by the fuel flow rate and the spray flow rate, and the reheater steam temperature is regulated by the gas recirculation flow rate. However, strict control of the steam temperature must be maintained to avoid thermal stress. Maintaining the steam temperature can be difficult due to heating value variation to the fuel source, time delay changes in the main steam temperature versus changes in fuel flow rate, difficulty of control of the main steam temperature control and the reheater steam temperature control system owing to the dynamic response characteristics of changes in steam temperature and the reheater steam temperature, and the fluctuation of inner fluid water and steam flow rates during the load-following operation. Up to the present time, the Proportional-Integral-Derivative Controller has been used to operate this system. However, it is very difficult to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error. This paper focuses on the characteristic comparison of the PID controller and the modified 2-DOF PID Controller (Two-Degrees-Freedom Proportional-Integral-Derivative) on the DCS (Distributed Control System). The method is to design an optimal controller that can be operated on the thermal generating plant in Seoul, Korea. The modified 2-DOF PID controller is designed to enable parameters to fit into the thermal plant during disturbances. To attain an optimal control method, transfer function and operating data from start-up, running, and stop procedures of the thermal plant have been acquired. Through this research, the stable range of a 2-DOF parameter for only this system could be found for the start-up procedure and this parameter could be used for the tuning problem. Also, this paper addressed whether an intelligent tuning method based on immune network algorithms can be used effectively in tuning these controllers.

  • PDF

Comparative Analysis on the Economic Effects of Integrated-Energy and Manufactured Gas Supply Sectors (집단에너지 부문과 도시가스 부문의 경제적 파급효과 비교분석)

  • Park, So-Yeon;Lee, Kyoung-Sil;Yoo, Seung-Hoon
    • Journal of Energy Engineering
    • /
    • v.23 no.2
    • /
    • pp.83-92
    • /
    • 2014
  • This paper attempts to conduct a comparative analysis on the economic effects of integrated-energy and manufactured gas supply sectors. To this end, an input-output (I-O) analysis is applied using most recently published 2011 I-O table. In particular, the two sectors are specified as exogeneous to identify the economic effects on own and other sectors. Production-inducing effect, value-added creation effect, and employment-inducing effect are quantified based on demand-driven model. Supply shortage effect and price pervasive effect are analyzed employing supply-driven model and Leontief price model, respectively. The results show that production-inducing effect, value-added creation effect, and employment-inducing effect of integrated-energy and manufactured gas supply sectors are estimated to be 1.5461 vs. 1.0297, 0.4759 vs. 0.1941, and 2.2885 vs. 0.4053 respectively. Price pervasive effects of the 10% increase in integrated-energy and manufactured gas supply sectors are computed to be 0.0127% and 0.1585%, respectively. This information can be utilized in forecasting the economic effects of introducing integrated-energy or manufactured gas as a heating source and the impacts of a rise in price of integrated-energy or manufactured gas on price level of other sectors.

Evaluation of Biological Critical Control Points Using Escherichia coli Genotyping (Escherichia coli Genotype을 이용한 생물학적 Critical Control Point의 적합성 평가)

  • Kim, Hak-Jae;Hahn, Tae-Wook;Juong, Ji-Hun;Bahk, Gyung-Jin;Hong, Chong-Hae
    • Food Science of Animal Resources
    • /
    • v.29 no.6
    • /
    • pp.695-701
    • /
    • 2009
  • This study was performed to evaluate the effectiveness of biological critical control points using the genetic profile of Escherichia coli isolates from pork cutting plants. Samples were collected from carcasses, equipment (knife, table, glove, transport belt, boning and skinning machine), the environment (wall and floor), and meat cuts during the cutting process from two plants. Pulsed-field gel electrophoresis (PFGE) was used to characterize the E. coli isolates. An identical genotype was detected from the carcasses, equipment, environment, and final meat cuts, and showed that the incoming carcasses, which were contaminated during transportation from slaughterhouses, were a major source of E. coli that was spread throughout processing. Also, consistent cross-contamination due to improper cleaning and disinfection procedures was another possibility. As a result, incoming carcasses and cleaning procedures should be considered critical control points in pork cutting plants, since a heating step is not used to inactivate microorganisms. Furthermore, the high rate (59.6%) of E. coli isolation indicates E. coli can be a good indicator in livestock processing plants even though it has genetic diversity.

Development of Thermo-Cosmetics Using Photothermal Effect of Gold Nanoparticles (금 나노입자의 광열효과를 이용한 온열화장품 개발)

  • Lee, Jae-Yeul;Kim, Bo-Mi;Park, Se-Ho;Choi, Yo-Han;Shim, Kyu-Dong;Moon, Sung-Bae;Jang, Eue-Soon;Yang, Seun-Ah;Jhee, Kwang-Hwan
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.41 no.1
    • /
    • pp.27-34
    • /
    • 2015
  • Many applications of nanoparticles have been developed since 1970s. Surface plasmon resonance (SPR) effect can be generated at the surface of nanoparticles by illumination. SPR is the resonant oscillation of conduction electrons at the surface material stimulated by incident light. The collisions between excited electrons and metal atoms can cause the production of thermal energy (photothermal effect). Here, we presented the development of thermo-cosmetics using photothermal effect of gold nanoparticles. Gold nanoparticles (GNPs) were chosen for it's low toxicity. We also and investigated the cell biocompatibility and heating effectiveness for photothermal effect of GNPs. Synthesized GNPs were verified by UV-vis spectrophotometer, where GNP has a characteristic absorbance spectrum. Concentration of GNP was measured by atomic absorption analyzer. The cytotoxicity was confirmed by MTT assay and double staining assay. Photothermal effect of GNP was demonstrated by the thermal increasing properties depending on GNP concentration, which was taken by an IR-thermal camera with a xenon lamp as the light source. If the thermal effect of GNP is applied for thermo-cosmetics, it can supply heat to skin by converting solar energy into thermal energy. Thus, cosmetics containing GNPs can provide benefits to people in the cold region or winter season for maintaining skin temperature, which lead to a positive effect on skin health.

Biochemical Methane Potential of Agricultural Byproduct in Greenhouse Vegetable Crops (국내 주요 시설채소 부산물의 메탄 생산 퍼텐셜)

  • Shin, Kook-Sik;Kim, Chang-Hyun;Lee, Sang-Eun;Yoon, Young-Man
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.44 no.6
    • /
    • pp.1252-1257
    • /
    • 2011
  • Number of crop residues generated at large amount in agriculture can be utilized as substrate in methane production by anaerobic digestion. Greenhouse vegetable crop cultivation that adopting intensive agricultural system require the heating energy during winter season, meanwhile produce waste biomass source for the methane production. The purpose of this study was to investigate the methane production potential of greenhouse vegetable crop residues and to estimate material and energy yield in greenhouse system. Cucumber, tomato, and paprika as greenhouse vegetable crop were used in this study. Fallen fruit, leaf, and stem residues were collected at harvesting period from the farmhouses (Anseong, Gyeonggi, Korea) adopting an intensive greenhouse cultivation system. Also the amount of fallen vegetables and plant residues, and planting density of each vegetable crop were investigated. Chemical properties of vegetable waste biomass were determined, and theoretical methane potentials were calculated using Buswell's formula from the element analysis data. Also, BMP (Biochemical methane potential) assay was carried out for each vegetable waste biomass in mesophilic temperature ($38^{\circ}C$). Theoretical methane potential ($B_{th}$) and Ultimate methane potential ($B_u$) off stem, leaf, and fallen fruit in vegetable residues showed the range of $0.352{\sim}0.485Nm^3\;kg^{-1}VS_{added}$ and $0.136{\sim}0.354Nm^3\;kg^{-1}VS_{added}$ respectively. The biomass yields of residues of tomato, cucumber, and paprika were 28.3, 30.5, and $21.5Mg\;ha^{-1}$ respectively. The methane yields of tomato, cucumber, and paprika residues showed 645.0, 782.5, and $686.8Nm^3\;ha^{-1}$. Methane yield ($Nm^3\;ha^{-1}$) of crop residue may be highly influenced by biomass yield which is mainly affected by planting density.

A Study on Development of Independent Low Power IoT Sensor Module for Zero Energy Buildings (제로 에너지 건축물을 위한 자립형 저전력 IoT 센서 모듈 개발에 대한 연구)

  • Kang, Ja-Yoon;Cho, Young-Chan;Kim, Hee-Jun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.12 no.3
    • /
    • pp.273-281
    • /
    • 2019
  • The energy consumed by buildings among the total national energy consumption is more than 10% of the total. For this reason, Korea has adopted the zero energy building policy since 2025, and research on the energy saving technology of buildings has been demanded. Analysis of buildings' energy consumption patterns shows that lighting, heating and cooling energy account for more than 60% of total energy consumption, which is directly related to solar power acquisition and window opening and closing operation. In this paper, we have developed a low - power IoT sensor module for window system to transfer acquired information to building energy management system. This module transmits the external environment and window opening / closing status information to the building energy management system in real time, and constructs the network to actively take energy saving measures. The power used in the module is designed as an independent power source using solar power among the harvest energy. The topology of the power supply is a Buck converter, which is charged at 4V to the lithium ion battery through MPPT control, and the efficiency is about 85.87%. Communication is configured to be able to transmit in real time by applying WiFi. In order to reduce the power consumption of the module, we analyzed the hardware and software aspects and implemented a low power IoT sensor module.

A Review on the Characteristics of Temperature Variation in Warm Needle (온침의 온도변화 특성에 대한 문헌 고찰 연구)

  • Lee, Ju Hyun;Jo, Hyo Rim;Kim, Seon Hye;Lee, Yeon Sun;Park, Se Won;Moon, So Ri;Jung, Chan Yung;Sung, Won Suk;Cho, Hyun Seok;Kim, Kyung Ho;Lee, Byung Wook;Kim, Eun-Jung
    • The Journal of Korean Medicine
    • /
    • v.40 no.3
    • /
    • pp.112-138
    • /
    • 2019
  • Objectives: The purpose of this study is to organize the research methods and results of studies related to the temperature of the warm needle for systematic utilization of warm needling technique. Methods: This study used the databases of nine (Pubmed, Science Direct, Cochrane Central, 4 Korean databases, CNKI, CiNii) to analyze temperature-related studies of the warm needle from 2000 to June 2019. Results: A total of 19 papers were included. Of these, 15 were used for mugwort, 2 for high frequency, and 1 for both mugwort and high frequency, and the other one for a ceramic heater. The maximum temperature rises as the amount of moxibustion increases. It is also affected by the density of moxa and the ignition part. There were 16 papers using stainless steel needles and 4 papers using a needle made of gold or silver to compare. In the area of the needle, the closer it is to moxibustion, the hotter it is. Compared to stainless steel needles, gold and silver needles showed almost twice the temperature. The effects of environment and radiant heat should be considered during warm needle procedures. Conclusions: There are various experimental methods such as warm needle technique materials, methods, measuring parts, measuring instruments, etc. The results were also very diverse. When setting the heating source, ignition part, size of moxibustion, etc. of warm needles, it should be implemented in a way that takes safety and validity into account. Considerations for temperature characteristics, radiant heat, etc. of warm needles will be needed when making warm needle apparatus.

Forecasting daily peak load by time series model with temperature and special days effect (기온과 특수일 효과를 고려하여 시계열 모형을 활용한 일별 최대 전력 수요 예측 연구)

  • Lee, Jin Young;Kim, Sahm
    • The Korean Journal of Applied Statistics
    • /
    • v.32 no.1
    • /
    • pp.161-171
    • /
    • 2019
  • Varied methods have been researched continuously because the past as the daily maximum electricity demand expectation has been a crucial task in the nation's electrical supply and demand. Forecasting the daily peak electricity demand accurately can prepare the daily operating program about the generating unit, and contribute the reduction of the consumption of the unnecessary energy source through efficient operating facilities. This method also has the advantage that can prepare anticipatively in the reserve margin reduced problem due to the power consumption superabundant by heating and air conditioning that can estimate the daily peak load. This paper researched a model that can forecast the next day's daily peak load when considering the influence of temperature and weekday, weekend, and holidays in the Seasonal ARIMA, TBATS, Seasonal Reg-ARIMA, and NNETAR model. The results of the forecasting performance test on the model of this paper for a Seasonal Reg-ARIMA model and NNETAR model that can consider the day of the week, and temperature showed better forecasting performance than a model that cannot consider these factors. The forecasting performance of the NNETAR model that utilized the artificial neural network was most outstanding.