• Title/Summary/Keyword: Electric Current

Search Result 4,830, Processing Time 0.035 seconds

Development of Eco-Efficiency Indicators for Yeosu Industrial Park (여수산업단지의 생태효율성지표 개발에 관한 연구)

  • Kim, Jung-In;Yun, Chang-Han;Yoon, Hyung-Sun
    • Clean Technology
    • /
    • v.16 no.3
    • /
    • pp.229-237
    • /
    • 2010
  • The industrial ecology indicators(IEI) for Yeosu Industrial Park were developed using eco-efficiency indicator(EEI). The key factors for the creation of IEI were two parts. One part is the value of the products which is selected as the total production value, the amount of ethylene production, the amount of light oil production instead of the total sales volume for Yeosu Industrial Park, since the currency exchange and the price of raw materials varied every year. The other part is the environmental burden. The electric consumption, the industrial water consumption, and the amount of discharged waste water are all officially opened to the public, were used in the calculation. Based on the value for the year of 2004, the IEI value for 2006 became worse to 0.954, but, was expected to be 1.153, a 15% improvement, for 2015 if the current EIP project is successfully performed.

A Study on the Design Method of Magnetizing Yoke Circuit Constant of 200kJ Magnetizer for Rotor Magnetization of High Capacity Permanent Magnet Motors (고용량 영구자석형 모터의 회전자 착자를 위한200 kJ급 착자기의 착자요크 회로정수 설계 방법에 관한 연구)

  • Jeong Minuk;SoongKeun Lee;GwonHu Baek;TaeKue Kim
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.28 no.2
    • /
    • pp.21-30
    • /
    • 2023
  • As the adoption and high-performance enhancement of Electric Vehicles continue, the demand for high-output motors and high-capacity Magnetizer for producing large-scale IPMSM is increasing. The maximum peak current of the magnetization and the capacitor discharge time, which are important factors in the magnetization process, are determined by the circuit constants of the magnetizer. In this paper, we analyze the magnetizing system using MATLAB SIMULINK to design the circuit constant of the magnetizing yoke for magnetizing design and present the design procedure for Design the circuit constant. As a result, the parameters of the magnetizing yoke were derived to be 0.015[ohm] and 0.035[mH] based on the capacitance of 15,000[uF] and voltage of 5,000[V].

A Study on the prediction of SOH estimation of waste lithium-ion batteries based on SVM model (서포트 벡터 머신 기반 폐리튬이온전지의 건전성(SOH)추정 예측에 관한 연구)

  • KIM SANGBUM;KIM KYUHA;LEE SANGHYUN
    • The Journal of the Convergence on Culture Technology
    • /
    • v.9 no.3
    • /
    • pp.727-730
    • /
    • 2023
  • The operation of electric automatic windows is used in harsh environments, and the energy density decreases as charging and discharging are repeated, and as soundness deteriorates due to damage to the internal separator, the vehicle's mileage decreases and the charging speed slows down, so about 5 to 10 Batteries that have been used for about a year are classified as waste batteries, and for this reason, as the risk of battery fire and explosion increases, it is essential to diagnose batteries and estimate SOH. Estimation of current battery SOH is a very important content, and it evaluates the state of the battery by measuring the time, temperature, and voltage required while repeatedly charging and discharging the battery. There are disadvantages. In this paper, measurement of discharge capacity (C-rate) using a waste battery of a Tesla car in order to predict SOH estimation of a lithium-ion battery. A Support Vector Machine (SVM), one of the machine models, was applied using the data measured from the waste battery.

Effect of Ambient Air Pollution on Years of Life Lost from Deaths due to Injury in Seoul, South Korea (대기오염물질이 손상으로 인한 손실수명연수에 미치는 영향: 서울특별시를 중심으로)

  • Sun-Woo Kang;Subin Jeong;Hyewon Lee
    • Journal of Environmental Health Sciences
    • /
    • v.49 no.3
    • /
    • pp.149-158
    • /
    • 2023
  • Background: Injury is one of the major health problems in South Korea. Few studies have evaluated both intentional and unintentional injury when investigating the association between exposure to air pollutants and injury. Objectives: We aimed to explore the association between short-term exposure to ambient air pollution and years of life lost (YLLs) due to injury. Methods: Data on daily YLLs for 2002~2019 were obtained from the the Death Statistics Database of the Korean National Statistical Office. This study estimated short-term exposure to particulate matter with an aerodynamic diameter of <10 ㎛ (PM10), particulate matter with an aerodynamic diameter of <2.5 ㎛ (PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3). This time series study was conducted using a generalized additive model (GAM) assuming a Gaussian distribution. We also evaluated a delayed effect of ambient air pollution by constructing a lag structure up to seven days. The best-fitting lag was selected based on smallest generalized cross validation (GCV) value. To explore effect modification by intentionality of injury (i.e., intentional injury [self-harm, assault] and unintentional injury), we conducted stratified subgroup analyses. Additionally, we stratified unintentional injury by mechanism (traffic accident, fall, etc.). Results: During the study period, the average daily YLLs due to injury was 307.5 years. In the intentional injury, YLLs due to self-harm and assault showed positive association with air pollutants. In the unintentional injury, YLLs due to fall, electric current, fire and poisoning showed positive association with air pollutants, whereas YLLs due to traffic accident, mechanical force and drowning/submersion showed negative associations with air pollutants. Conclusions: Injury is recognized as preventable, and effective strategies to create a safe society are important. Therefore, we need to establish strategies to prevent injury and consider air pollutants in this regard.

Development of overhead distribution line diagnosis system program (가공 배전선로 진단시스템 프로그램 개발)

  • Dong Hyun Chung;Deok Jin Lee
    • Smart Media Journal
    • /
    • v.12 no.5
    • /
    • pp.81-87
    • /
    • 2023
  • In this paper, accidents in high-voltage overhead distribution lines, which provide stable power supply in the power system, cause inconvenience in life and disruption of production of companies. 22.9 [kV] high-voltage overhead power distribution lines aim to improve reliability and stability, such as damage caused by rain, snow, wind, etc., or electric shock prevention. Therefore, in order to prevent wire disconnection accidents due to deterioration of electrical conductivity or tensile strength due to corrosion of overhead distribution lines, it is necessary to prevent unexpected accidents in the future through regular inspection and repair. In order to diagnose deterioration due to corrosion of distribution lines, a diagnostic system (measuring instrument) is installed on the wires to monitor the condition of the wires. The manager on the ground receives the measured data through ZigBee wireless communication, controls the diagnosis system through the diagnosis system program, and grasps the condition of the overhead distribution line through the measured data and photographed photos, and predicts the life of the wire along with the visual inspection method. developed a program.

Effect of Electron Beam Irradiation on the Opto-Electrical and Transparent Heater Property of ZnO/Cu/ZnO Thin Films for the Electric Vehicle Application (전자빔 조사에 따른 ZnO/Cu/ZnO 박막의 전기광학적 특성 및 전기자동차용 투명 발열체 특성)

  • Yeon-Hak Lee;Min-Sung Park;Daeil Kim
    • Korean Journal of Materials Research
    • /
    • v.33 no.11
    • /
    • pp.497-501
    • /
    • 2023
  • ZnO/Cu/ZnO (ZCZ) thin films were deposited at room temperature on a glass substrate using direct current (DC) and radio frequency (RF, 13.56 MHz) magnetron sputtering and then the effect of post-deposition electron irradiation on the structural, optical, electrical and transparent heater properties of the films were considered. ZCZ films that were electron beam irradiated at 500 eV showed an increase in the grain sizes of their ZnO(102) and (201) planes to 15.17 nm and 11.51 nm, respectively, from grain sizes of 13.50 nm and 10.60 nm observed in the as deposited films. In addition, the film's optical and electrical properties also depended on the electron irradiation energies. The highest opto-electrical performance was observed in films electron irradiated at 500 eV. In a heat radiation test, when a bias voltage of 18 V was applied to the film that had been electron irradiated at 500 eV, its steady state temperature was about 90.5 ℃. In a repetition test, it reached the steady state temperature within 60 s at all bias voltages.

A Study on the Short-circuit Protection System for Learning Teaching Instruction Using Incandescent Light Bulb (백열전구를 이용한 학습 교구용 단락보호장치에 대한 고찰)

  • Hong-yong Kim
    • Journal of the Society of Disaster Information
    • /
    • v.19 no.4
    • /
    • pp.844-850
    • /
    • 2023
  • Purpose: This paper is about the development of a short-circuit protection power supply device using incandescent bulbs and its application for educational materials. This article, which considers electrical safety and energy conservation at the same time, has many kinds of potential applications for both educational and industrial areas. The above mentioned short-circuit protection power supply device using incandescent bulbs enhances safety and efficiency compared to normal current power supply devices. Additionally, as an educational materials, it can be used for electric safety training, and provides practical electrical safety knowledge on our actual life. Method: Using incandescent bulbs, design new type of short-circuit protection power supply device, and through verifying the function and safety of the device, make new type device, and applying it for an educational tool. Conclusion: This study is to develop new type of power supply device, and verify the possibility of the application for the device as an educational materials. Through this research, show an innovative solution, which contribute to electrical safety and energy conservation, and open the potential possibility on educational and industrial sectors.This kind of research is expected to contributes to enhanced research, and education on electrical safety and energy conservation management.

Plant diversity of the pads of electric towers along the deltaic Mediterranean coast of Egypt

  • Kamal Shaltout;Hani Beshara;Yassin Al-Sodany;Ahmed Sharaf, El-Din;Ragab El-Fahar
    • Journal of Ecology and Environment
    • /
    • v.47 no.3
    • /
    • pp.63-74
    • /
    • 2023
  • Background: Comparing with the several types of infrastructures, linear infrastructures are known to facilitate the spread of undesirable species in ecosystems. Recently, some new man-made habitats (e.g., gravel pads of the high-voltage towers, solid wastes and sewage habitats) were established along the Deltaic Mediterranean coast of Egypt as a result of the construction of the E-W coastal international highway. The current study evaluates the floristic composition associated with the pads of high-voltage towers that had been constructed for stabilizing the power line towers in the North Nile Delta. Plant cover was measured for 22 randomly stand. Results: Eighty-four species were recorded, of which 35 are perennials (41.6%), 2 biennials (2.3%) and 47 annuals (56.0%) belonging to 23 families. The largest families were Asteraceae (16 species), Poaceae (15 species), Chenopodiaceae (12 species), and Fabaceae (7 species). Ten aliens (10.7%) out of the 84 species were recorded. Therophytes have the highest percentage (58%), followed by hemicryptophytes (14%), chamaephytes (11%). Six vegetation groups were recognized in the study area after the application of two way indicator species analysis (TWINSPAN), Arthrocnemum macrostachyum, Phragmites australis, and Mesembryanthemum nodiflorum have the highest presence percentage. Both of Salsola cyclophylla and Solanum villosum were recorded for the first time in North Nile Delta. Natural habitat had the highest α-diversity, but the lowest β-diversity (4.9, 15.4), while gravel pads had the reverse (2.7, 30.8). Some species which are native to the desert habitats (e.g., Rumex pictus, Salsola kali, and Carthamus tenuis) were able to invade the North Nile Delta. Conclusions: Habitat of gravel pads is an expressing form about the intense of disturbance in Deltaic Mediterranean coast of Egypt. More of efforts should be carried out to avoid more human disturbances that creating as ruderal habitats which open the gate to invasive species in the flora of North Nile Delta.

A Study on the Current Fire Insurance Subscription and Solutions for Ensuring the Safety of the Traditional Market (전통시장 안전성 확보를 위한 개선방안: 화재보험 가입실태를 중심으로)

  • Kim, Yoo-Oh;Byun, Chung-Gyu;Ryu, Tae-Chang
    • Journal of Distribution Science
    • /
    • v.9 no.4
    • /
    • pp.43-50
    • /
    • 2011
  • Concerning the risk factors of the outbreak of a fire in a traditional market, most of those markets are located in downtown areas or residential areas; thus, although their location may be favorable in terms of marketability, they face a potential risk in that a fire may develop into a large blaze owing to poor environment or the absence of facilities prepared for disaster during a fire. Moreover, as many people are densely poised in the markets, it is very probable that a fire may occur owing to the excessive use of heaters in the winter as well as the reckless use of electric and gas facilities. It seems that traditional markets encounter difficulty being insured against fire, because of their vulnerability and that the vast majority of small-scale sellers are likely to suffer mental anguish and tremendous physical injury in case of a fire. However, most of those sellers in the traditional markets are hand-to-mouth sellers, and they lack awareness of safety concerns and have insufficient experience in safe facility management. As small-scale sellers constitute the majority in the traditional market, the subscription rate of fire insurance in most of the traditional markets is low for the reasons of their needy circumstances and their financial burden. Statistically, the subscription by street vendors is non-existent; therefore, these vendors have a fairly limited access to indemnification after fire damage. Because of these problems, this study's purpose is to identify the current level of insurance subscription by these markets, which are exposed to poor facilities and vulnerability to fire. In order to fix this, it appears that shop owners and consumers will have to band together. For this study, we executed a fire policyholder fact-finding mission at traditional markets with approximately 108 and 981 stores. The research method was executed by an investigation using one-on-one individual interviews using a questionnaire. The contents investigated current insurance subscriptions. The method of analysis looked at the difference of insured amount according to volume size through cross-tabulation of the difference of insured amount by possession form, difference of insured amount by market form, difference of insured amount by category of business, difference of insured amount by market size, etc. Furthermore, the study should be used to propose solutions for problems through theoretical review with the use of a literature research, because the field case study was through interviews with the persons concerned, and the survey of the current insurance subscriptions by traditional market shopkeepers. The traditional market would generally have difficulty affording fire insurance. Fire insurance subscription rates of most of the market proved to be inactive, because of the economic burden of payment. Lack of funds is thought to be the main factor that causes a lack of realization about the necessity of fire insurance. In addition to expensive insurance premiums, sometimes, the companies' valuation of the businesses is lower than their actual valuations, and they do not pay out enough during a claim. The research presents an improvement plan that, when presented at the traditional markets, may strengthen their ability to procure fire insurance through the help of the central government. Researchers connected with the traditional market mainly accomplish the initial research. However, although this research has its limitations, it offers considerable benefits. For future researchers, I would suggest looking at several regions for comparison.

  • PDF

Structural Behavior of Mixed $LiMn_2O_4-LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ Cathode in Li-ion Cells during Electrochemical Cycling

  • Yun, Won-Seop;Lee, Sang-U
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2011.05a
    • /
    • pp.5-5
    • /
    • 2011
  • The research and development of hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and electric vehicle (EV) are intensified due to the energy crisis and environmental concerns. In order to meet the challenging requirements of powering HEV, PHEV and EV, the current lithium battery technology needs to be significantly improved in terms of the cost, safety, power and energy density, as well as the calendar and cycle life. One new technology being developed is the utilization of composite cathode by mixing two different types of insertion compounds [e.g., spinel $LiMn_2O_4$ and layered $LiMO_2$ (M=Ni, Co, and Mn)]. Recently, some studies on mixing two different types of cathode materials to make a composite cathode have been reported, which were aimed at reducing cost and improving self-discharge. Numata et al. reported that when stored in a sealed can together with electrolyte at $80^{\circ}C$ for 10 days, the concentrations of both HF and $Mn^{2+}$ were lower in the can containing $LiMn_2O_4$ blended with $LiNi_{0.8}Co_{0.2}O_2$ than that containing $LiMn_2O_4$ only. That reports clearly showed that this blending technique can prevent the decline in capacity caused by cycling or storage at elevated temperatures. However, not much work has been reported on the charge-discharge characteristics and related structural phase transitions for these composite cathodes. In this presentation, we will report our in situ x-ray diffraction studies on this mixed composite cathode material during charge-discharge cycling. The mixed cathodes were incorporated into in situ XRD cells with a Li foil anode, a Celgard separator, and a 1M $LiPF_6$ electrolyte in a 1 : 1 EC : DMC solvent (LP 30 from EM Industries, Inc.). For in situ XRD cell, Mylar windows were used as has been described in detail elsewhere. All of these in situ XRD spectra were collected on beam line X18A at National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory using two different detectors. One is a conventional scintillation detector with data collection at 0.02 degree in two theta angle for each step. The other is a wide angle position sensitive detector (PSD). The wavelengths used were 1.1950 ${\AA}$ for the scintillation detector and 0.9999 A for the PSD. The newly installed PSD at beam line X18A of NSLS can collect XRD patterns as short as a few minutes covering $90^{\circ}$ of two theta angles simultaneously with good signal to noise ratio. It significantly reduced the data collection time for each scan, giving us a great advantage in studying the phase transition in real time. The two theta angles of all the XRD spectra presented in this paper have been recalculated and converted to corresponding angles for ${\lambda}=1.54\;{\AA}$, which is the wavelength of conventional x-ray tube source with Cu-$k{\alpha}$ radiation, for easy comparison with data in other literatures. The structural changes of the composite cathode made by mixing spinel $LiMn_2O_4$ and layered $Li-Ni_{1/3}Co_{1/3}Mn_{1/3}O_2$ in 1 : 1 wt% in both Li-half and Li-ion cells during charge/discharge are studied by in situ XRD. During the first charge up to ~5.2 V vs. $Li/Li^+$, the in situ XRD spectra for the composite cathode in the Li-half cell track the structural changes of each component. At the early stage of charge, the lithium extraction takes place in the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component only. When the cell voltage reaches at ~4.0 V vs. $Li/Li^+$, lithium extraction from the spinel $LiMn_2O_4$ component starts and becomes the major contributor for the cell capacity due to the higher rate capability of $LiMn_2O_4$. When the voltage passed 4.3 V, the major structural changes are from the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, while the $LiMn_2O_4$ component is almost unchanged. In the Li-ion cell using a MCMB anode and a composite cathode cycled between 2.5 V and 4.2 V, the structural changes are dominated by the spinel $LiMn_2O_4$ component, with much less changes in the layered $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, comparing with the Li-half cell results. These results give us valuable information about the structural changes relating to the contributions of each individual component to the cell capacity at certain charge/discharge state, which are helpful in designing and optimizing the composite cathode using spinel- and layered-type materials for Li-ion battery research. More detailed discussion will be presented at the meeting.

  • PDF