• Title/Summary/Keyword: great power

Search Result 1,319, Processing Time 0.023 seconds

Aesthetic Education into the Internal Logic and Practice Path of Rural Characteristic Industrial Construction

  • Lu Ziyan
    • International Journal of Advanced Culture Technology
    • /
    • v.11 no.4
    • /
    • pp.273-278
    • /
    • 2023
  • Aesthetic education in a variety of forms in the sublimation of the people's feelings, sublimation of the soul. It is of great significance to inherit and develop rural culture and to maintain cultural diversity. At present, rural characteristic industry is an important form of development to promote rural economic development, protect rural cultural diversity and continue rural culture. It is of great practical significance to guide the development direction of rural characteristic industry, strengthen the value connotation of rural characteristic industry and stimulate the endogenous power of rural characteristic industry. At the same time, it is of great significance to promote the development of aesthetic education and broaden the path of aesthetic education.

Spatial Variation Characteristics of Seismic Motions through Analysis of Earthquake Records at Fukushima Nuclear Power Plant (후쿠시마 원자력발전소 지진 계측 기록 분석을 통한 지진파의 공간적 변화 특성 평가)

  • Ha, Jeong-Gon;Kim, Mi Rae;Kim, Min Kyu
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.25 no.5
    • /
    • pp.223-232
    • /
    • 2021
  • The spatial variation characteristics of seismic motions at the nuclear power plant's site and structures were analyzed using earthquake records obtained at the Fukushima nuclear power plant during the Great East Japan Earthquake. The ground responses amplified as they approached the soil surface from the lower rock surface, and the amplification occurred intensively at about 50 m near the ground. Due to the soil layer's nonlinear characteristics caused by the strong seismic motion, the ground's natural frequency derived from the response spectrum ratio appeared to be smaller than that calculated from the shear wave velocity profile. The spatial variation of the peak ground acceleration at the ground surface of the power plant site showed a significant difference of about 0.6 g at the maximum. As a result of comparing the response spectrums at the basement of the structure with the design response spectrum, there was a large variability by each power plant unit. The difference was more significant in the Fukushima Daiichi site record, which showed larger peak ground acceleration at the surface. The earthquake motions input to the basement of the structure amplified according to the structure's height. The natural frequency obtained from the recorded results was lower than that indicated in the previous research. Also, the floor response spectrum change according to the location at the same height was investigated. The vertical response on the foundation surface showed a significant difference in spectral acceleration depending on the location. The amplified response in the structure showed a different variability depending on the type of structure and the target frequency.

Impact Power Characteristics as Behavior of Real Impact Source(Child) (실충격원(어린이)의 충격 발생행위에 따른 충격력 특성에 관한 연구)

  • Kim, Kyoung-Woo;Choi, Gyoung-Seok;Jeong, Young-Sun;Yang, Kwan-Seop
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.15 no.5 s.98
    • /
    • pp.542-549
    • /
    • 2005
  • Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance In residential buildings. Running and jumping impact sound by child are one of the most irritating noises in an apartment buildings. It's necessary to know that the impact power characteristics of real impact source in an apartment buildings. This study aims to Investigate the impact power characteristics and impact power time of running and jumping by child. This study carried out investigation through the 159 children in school. The results of this study is that jumping impact power is greater than running impact power.

The effect of imperfect power control on the capacity of reverse channel in cellular CDMA system with antenna arrays (안테나 배열을 이용한 CDMA 셀룰라 시스템에서 불완전 전력제어가 역방향 채널 용량에 미치는 효과)

  • 김씨알;오성근
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.21 no.2
    • /
    • pp.471-482
    • /
    • 1996
  • In this paper, we analyze the effect of imperfect power control on the capacity of the reverse channel in CDMA cellular system with antenna arrays in the base station. For imperfect power control, we assume that the received power at the base station from the users within each cell has log-normal distribution, and we also consider the effect of imperfect power control of co-channel interferences which arise from both its own cell and outer cells. From the result of numerical analysis, we show that the degree of power control gives a great influence on the capacity of CDMA celluar system with antenna arrays, and also that antenna arrays at the base station can improve greatly the system capacity even when the power control is imperfect.

  • PDF

Development of Power Supply Device for Load Characteristic Experimentation (부하특성실험을 위한 전원공급장치 개발)

  • Lee, Jong-Pil;Ji, Pyeong-Shik;Lim, Jae-Yoon
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.54 no.2
    • /
    • pp.101-107
    • /
    • 2005
  • The reduced power quality due to some of disturbances on power system has great influence on the efficient and life of load for bad with serious economic loss. The response of load about disturbance needs to analysis quantitatively in detail to improve load characteristics. In this research, a power supply device is developed to supply disturbed power similar to that of power system. The developed device can output a voltage and frequency from 180[V] to 240[V], 55[Hz] to 65[Hz] respectively. The most outstanding feature of this device is a function to be performed steady and dynamic state characteristic experiment on load or appliances. Also, this device is designed to include high accuracy ouput and simple measurement.

A Pspice Model of MOS-Controlled Thyrister for Circuit Simlulation (회로 시뮬레이션을 위한 MOS 제어 다이리스터의 PSPICE 모델)

  • Lee, Young-Kook;Hyun, Dong-Seok
    • Proceedings of the KIEE Conference
    • /
    • 1995.07a
    • /
    • pp.382-384
    • /
    • 1995
  • The advancement of power semiconductor devices has given great attribution to the performance and reliability or power conversion systems. But contemporary power devices have room for improvement. So much interest and endeavor are being applied to develop an improved power devices. The MOS-Controlled Thyristor(MCT)is a recently developed power device which combines four layers thyristor structure and MOS-gate. Owing to advantages compared to other devices in many respects, the MCT attracts much notice recently. Nowadays, in designing and manufacturing power conversion systems, the importance of circuit simulation for reducing cost and time is incensed. And to excute the simulation that resemble the real system as much as possible, to develop a model of power device that provides properly static and dynamic characteristics is important. So, this paper presents a PSPICE model of the MCT considering dynamic characteristics.

  • PDF

Design and Process Development in High Voltage Insulated Gate Bipolar Transistors (IGBTs)

  • Kim, Su-Seong
    • The Magazine of the IEIE
    • /
    • v.35 no.7
    • /
    • pp.57-71
    • /
    • 2008
  • The last decade has witnessed great improvements in power semiconductor devices thanks to the advanced design and process, which have made it possible to significantly improve the electrical performances of electronic systems while simultaneously reducing their site, weight and perhaps most importantly reducing their cost. Among the power semiconductor devices, IGBT will be a key semiconductor component for power industry since it has a huge potential to cover large areas of power electronics from small home appliances to heavy industries. Currently, only a few limited power semiconductor manufacturers supply most of the industrial consumptions of power IGBT and its modules. Therefore, a large portion of technology in the power industry is dependent on other advanced countries. In this regard, to independently build power IGBT devices and the relevant power module technology, Korean government initiated a new 5-year project 'Power IT,' which also aimed at booming the business of the power semiconductor and the allied industries. With the success of this power IT project, it is expected that the power semiconductor technology will be a basis to foster the high power semiconductor industry and moreover, there will be more innovative developments in the Korea region and globally Also, forming the channel between the customers and suppliers, it is possible to effectively develop the customized power products, which could strengthen the competitiveness of Korean power industry. Furthermore, the power industry including semiconductor manufacturers will be technologically self-supporting and be able to obtain good business opportunities, and eventually increase the share in the growing power semiconductor market, which could be positioned as a major industry in Korea.

  • PDF

A Study on AC/DC Converter Design of High Efficiency for Inverter Resistance Welder (인버터 저항용접기의 전력효율 향상을 위한 AC/DC 컨버터 설계에 관한 연구)

  • Kwak, D.K.;Jung, W.S.;Kang, W.C.
    • Proceedings of the KIPE Conference
    • /
    • 2016.07a
    • /
    • pp.40-41
    • /
    • 2016
  • The inverter resistance welder requires AC/DC converter of high efficiency because the converter changes a commercial ac power source to low voltage dc power source. Harmonic components that occur in the conversion process of converter decrease system power factor and deal great damage in electric power system. To improve such problems, this paper proposes a high efficiency AC/DC converter for inverter resistance welder. The switching devices in the proposed converter are operated by soft switching technique using a new quasi-resonant circuit. As a result, the proposed AC/DC converter obtains low switching power loss and high efficiency.

  • PDF

A Study on Deterioration Evaluation Method by Condition Monitoring and Diagnosis for Aging Oil-immersed Power Transformers (유입식 변압기의 상태진단을 통한 노후도 평가 방법)

  • Chang, Jeong-Ho;Lee, Sung-Hun;Lee, Heung-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.63 no.2
    • /
    • pp.297-305
    • /
    • 2014
  • Nowadays new water supply projects have been on the decline as the water-power constructions have saturated, which means that the existing power equipment have slowly aged and they require more efforts to maintain the system performance. An effective asset management method of power equipment has become a great necessity from both economical and technical aspects. To be balanced, the asset management should look into all three parts: management, engineering, and information. The purpose of this paper is to study a Risk-Based Maintenance (RBM) matrix method through the deterioration evaluation algorithm for an efficient reliability assessment of oil-immersed power transformers by considering both asset management and technical evaluation. Make use of this result, the equipment will be decided to be replace or repair otherwise on service.

Dynamic Adjustment of Ad hoc Traffic Indication Map(ATIM) window to save Power in IEEE 802.11 DCF

  • Nam, Jae-Hyun
    • Journal of information and communication convergence engineering
    • /
    • v.6 no.3
    • /
    • pp.343-347
    • /
    • 2008
  • Wakeup schemes that turn off sensors' radio when communication is not necessary have great potential in energy saving. At the start of each beacon interval in the IEEE 802.11 power saving mode specified for DCF, each node periodically wakes up for duration called the ATIM Window. However, in the power saving mechanism specified in IEEE 802.11, all nodes use the same ATIM window size. Since the ATIM window size critically affects throughput and energy consumption, a fixed ATIM window does not perform well in all situations. This paper proposes an adaptive mechanism to dynamically choose an ATIM window size according to network condition. Simulation results show that the proposed scheme outperforms the IEEE 802.11 power saving mechanism in terms of the amount of power consumed and the packet delivery ratio.