• Title/Summary/Keyword: Impact drive

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A Study on Promotion Policy of Korean Design (I) (한국 디자인 진흥정책에 관한 연구(1))

  • 윤태호
    • Archives of design research
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    • v.6 no.1
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    • pp.11-22
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    • 1993
  • The purpose of this study was to provide basic information for establishment of a desirable design promotion policy drive by research and analysis of recognition to design by consumers (including students) and designers and their level, merchandise evaluation evaluation and obstructing factors in revitalization of designs. To implement such purpose as referred to hereinabove, research was made by introduction of questionaires which were distributed to 500 persons of consumers group and 350 individuals of registered designers in Seoul, and for analysis of the data, density and percentage (%) were obtained by use of SAS Package and the dispersed analysis and correlationship were added for necessary parts. The result of study is summarized as follows; (l)The consumers remind the design as costume (21%) and molding (20%), and the designers remind it as creativity (27%) & molding (14%) respectively and the reminding of design by the two groups was indicated very simi lar. (p < 0.001) (2)As per the recogni tion of roles by the designers the research has highly indicated as contribution to improving living standards or development of economy & industry, and also indicated that it creates excessive consumption with sti$$\mu$ative manner. (3)The design reacts as an important parameter in selecting cri teria of merchandises and deciding factors for purchasing and also, in enhancement of competitive power of merchandise impact of design (2.36) was regarded very high. (4)The Korean-made home appliances in image is assessed as vulnerable than that of Japanese products, and the product designing level is also shown difference from advanced countries (1.36), but has indicated as somewhat better than those competitive nations (0.51) (5)The satisfaction to design policy of the Gov't is very low (1.69) and they recommended for new establishment of Policy undertaking department within the Gov't and indicated reasearch & development of design as the major issue. In regard to the above I'd like to emphasize the design industry $$\mu$t be dealt with the national level as a whole in order to promote thereof.

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A Ripple Rejection Inherited RPWM for VSI Working with Fluctuating DC Link Voltage

  • Jarin, T.;Subburaj, P.;Bright, Shibu J V
    • Journal of Electrical Engineering and Technology
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    • v.10 no.5
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    • pp.2018-2030
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    • 2015
  • A two stage ac drive configuration consisting of a single-phase line commutated rectifier and a three-phase voltage source inverter (VSI) is very common in low and medium power applications. The deterministic pulse width modulation (PWM) methods like sinusoidal PWM (SPWM) could not be considered as an ideal choice for modern drives since they result mechanical vibration and acoustic noise, and limit the application scope. This is due to the incapability of the deterministic PWM strategies in sprawling the harmonic power. The random PWM (RPWM) approaches could solve this issue by creating continuous harmonic profile instead of discrete clusters of dominant harmonics. Insufficient filtering at dc link results in the amplitude distortion of the input dc voltage to the VSI and has the most significant impact on the spectral errors (difference between theoretical and practical spectra). It is obvious that the sprawling effect of RPWM undoubtedly influenced by input fluctuation and the discrete harmonic clusters may reappear. The influence of dc link fluctuation on harmonics and their spreading effect in the VSI remains invalidated. A case study is done with four different filter capacitor values in this paper and results are compared with the constant dc input operation. This paper also proposes an ingenious RPWM, a ripple dosed sinusoidal reference-random carrier PWM (RDSRRCPWM), which has the innate capacity of suppressing the effect of input fluctuation in the output than the other modern PWM methods. MATLAB based simulation study reveals the fundamental component, total harmonic distortion (THD) and harmonic spread factor (HSF) for various modulation indices. The non-ideal dc link is managed well with the developed RDSRRCPWM applied to the VSI and tested in a proto type VSI using the field programmable gate array (FPGA).

An Analysis of the Impact of National ICT Development on Economic Growth (국가정보화가 국가경제 성장에 미치는 영향분석 - 패널데이터 분석을 중심으로 -)

  • JIN, SANGKI;Cho, Cheong Moon
    • Informatization Policy
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    • v.19 no.3
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    • pp.64-93
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    • 2012
  • This paper attempts to empirically verify the theoretical assumption that ICT factors actually affect national economic development. To this end, this study uses a research model, 'balance model of supply-demand', which consists of IT supply, IT demand and IT policy dimensions. Also, this paper employs several socio-economic factors such as 'size of population', 'consumer price increase', 'national transparency', and 'education'as the moderating variables. The result through the panel data analysis finds it statistically relevant to relate the ICT capacity to each country's economic growth. Also, the study finds that moderating variables were highlighted as important elements of national development: these variables actually moderate the ICT capacity's effects on each surveyed nation's economic growth. Finally, this paper suggests policy implications that nations should consider when developing national informatization policies to drive national economic growth.

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Polymer Phosphorescence Device using a New Green Emitting Ir(III) Complex

  • Lee, Chang-Lyoul;Das, Rupasree Ragini;Noh, Yong-Young;Kim, Jang-Joo
    • Journal of Information Display
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    • v.3 no.1
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    • pp.6-10
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    • 2002
  • We have synthesized a new green Ir(III) complex fac-tris-(3-methyl-2-phenyl pyridine)iridium(III) $Ir(mpp)_3$ and fabricated phosphorescent polymer light-emitting device using it as a triplet emissive dopant in PVK. $Ir(mpp)_3$ showed absorption centered at 388 nm corresponding to the $^1MLCT$ transition as .evidenced by its extinction coefficient of the order of $10^3{\cdot}$ From the PL and EL spectra of the $Ir(mpp)_3$ doped PVK film, the emission maximum was observed at 523 nm, due to the radiative decay from the $^3MLCT$ state to the ground state, confirming a complete energy transfer from PVK to $Ir(mpp)_3$. The methyl substitution has probably caused a red shift in the absorption and emission spectrum compared to $Ir(mpp)_3$. The device consisting of a 2 % doped PVK furnished 4.5 % external quantum efficiency at 72 $cd/m^2$ (current density of 0.45 $mA/cm^2$ and drive voltage of 13.9 V) and a peak luminance of 25,000 $cd/m^2$ at 23.4 V (494 $mA/cm^2$). This work demonstrates the impact of the presence of a methyl substituent at the 3-position of the pyridyl ring of 2-phenylpyridine on the photophysical and electroluminescence properties.

A Study on the V2G Application using the Battery of Electric Vehicles under Smart Grid Environment (스마트그리드 환경에서 전기자동차 배터리를 이용한 V2G의 활용방안에 관한 연구)

  • Choi, Jin-Young;Park, Eun-Sung
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.63 no.1
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    • pp.40-45
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    • 2014
  • This study examines the system and process of battery stored energy in vehicles and suggest the effective area for the use of V2G(vehicle-to-grid) from Jeju Smart Grid Demonstration Project. V2G means technology of electric power transmission from the battery of electric-drive vehicles to state grid. As for the increasing of effectiveness for demand-side control, V2G is a very good alternative. In the U.S., the utilization of electric vehicles is under 40% on average. In this case, we can use he battery of electric vehicle as role of frequency regulation or generator of demand-side resource. V2G, which is the element of Smart Transportation, consists of electric vehicle battery, BMS(battery management system), OBC(on-board charger), charging infrastructure, NOC(network operating center) and TOC(total operation center). V2G application has been tested for frequency regulation to secure the economical efficiency in the United States. In this case, the battery cycle life is not verified its disadvantage. On the other hand, Demand Response is required by low c-rate of battery in electric vehicle and It can be small impact on the battery cycle life. This paper concludes business area of demand response is more useful than frequency regulation in V2G application of electric vehicles in Korea. This provides the opportunity to create a new business for power grid administrator with VPP(virtual power plant).

Development of Analytical Model of Spindle and Rack Gear Systems for Knuckle Boom Crane (굴절식 크레인의 스핀들과 랙 기어 응력 해석 모델 개발)

  • An, Junwook;Lee, Kwang Hee;Gyu, Yusung;Jo, Je Sang;Lee, Chul Hee
    • Journal of Drive and Control
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    • v.14 no.2
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    • pp.23-29
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    • 2017
  • In this study, a flexible multi-body dynamic simulation model of a knuckle boom crane is developed to evaluate the stress of spindle and rack gears under dynamic working conditions. It is difficult to predict potential critical damage to a knuckle boom crane if only the static condition is considered during the development process. To solve this issue, a severe working scenario (high speed with heavy load) was simulated as a boundary condition for testing the integrity of the dynamic simulation model. The crane gear model is defined as a flexible body so contact analysis was performed. The functional motion of a knuckle boom crane is generated by applying forces at each end of the rack gear, which was converted from hydraulic pressure measured for the experiment. The bending and contact stress of gears are theoretically calculated to validate the simulation model. In the simulation, the maximum stress of spindle and rack gears are observed when the crane abruptly stops. Peak impact force is produced at the contact interface between pinion and rack gears due to the inertia force of the boom. However, the maximum stress (bending/contact) of spindle and rack are under the yield stress, which is safe from damage. By using the developed simulation model, the experiment process is expected to be minimized.

Impacts of Urban Green Spaces on Air Quality (도심지역 녹지의 국지적 대기환경영향에 관한 연구)

  • Joo, Hyun Soo;Kim, Seogcheol
    • Korean Chemical Engineering Research
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    • v.47 no.3
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    • pp.386-393
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    • 2009
  • This study was to find out the quantitative relation between urban treed area(neighborhood parks) and the atmosphere environment in real condition, focusing the gas-phase non-reacting air pollutants(SOx and NOx) decreasing function of trees in urban area. It also developed a quantitative analysis method for evaluation of the atmosphere influence in the type of treed areas. We set up the Pagoda Park in Seoul and its neighbourhood as a modelling area to analyse air quality impacts by urban neighbourhood park trees. From the modelling result of the Pagoda Park case study, it is concluded that urban neighbourhood park has an important meaning to suppress construction of emission sources which drive the urban polluted air quality worse, even though park's trees have relatively small air purifying function. Especially in the urban area severely contaminated by air pollutants, the first considered air quality management policy is conservation of green spaces in neighborhood park.

UK Urban Regeneration Policy for Comprtitiveness: A Government Perspective

  • Thorpe, Keith
    • Land and Housing Review
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    • v.8 no.2
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    • pp.33-53
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    • 2017
  • The UK Government's approach to how to deliver regeneration in its towns and cities has changed considerably in recent years. Traditionally, urban regeneration policy focused on reversing physical, economic and social decline in an area where market forces would not do this without intervention. Since 2010 urban regeneration has become a vital part of the Government's approach to increasing local growth and competitiveness and building a strong and balanced economy. The current emphasis is on a place-based approach to regeneration that builds on the particular strengths of different places to drive growth and addresses the factors that hold them back. This paper outlines the key features of current UK urban regeneration policy and how interventions to support regeneration and growth are being pursued at different spatial scales to ensure all parts of the country benefit. They include pan regional initiatives like the Northern Powerhouse and Midlands Way, to groups of local authorities operating at a sub regional level (combined authorities/city regions), Local Enterprise Partnerships, and a variety of smaller scale programmes delivering regeneration in areas of economic and social decline. The paper explains some of the policy instruments and funding programmes available to support regeneration, and provides case studies of some major urban regeneration projects that illustrate the new approach including housing and infrastructure improvements like the planned High Speed Rail 2 line. These are supporting regeneration through the creation of strategic partnerships involving government, places and investors. The paper concludes with some lessons from past and future regeneration schemes to improve their effectiveness and impact on places and enhance local growth potential.

Analysis of Impact Factors on the Variation of PM10 Concentration in Seoul, Korea - Focus on PM10 Concentration Measured in 2003, 2004 -

  • Song, Hyung-Do;Lee, Hee-Chul;Kwon, Chun-Kyoung;Kim, Rhok-Ho;Kim, Sang-Kyun;Lee, Jae-Bum
    • Asian Journal of Atmospheric Environment
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    • v.6 no.1
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    • pp.1-13
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    • 2012
  • To identify the primary factor affected the decreased $PM_{10}$ concentration in Seoul which is the capital city of Korea, wind speed and emissions in 2003 and 2004 were analyzed. The level of air pollution is intense in Seoul and continually increased since the late 1990s. However the concentration of $PM_{10}$ has been greatly declined recently. In particular, the concentration of $PM_{10}$ decreased 14% in 2003 and 2004 excluding the Asian dust periods. It is suggested that the major factors for the decrease are differences in wind speed between the two years and the period of constant breeze. In 2003, intense Asian dust events happened frequently and it increased the concentration of total $PM_{10}$. The intense dust events were influence by the speed and duration of the wind. It is considered that the meteorological condition was the primary drive for the change of the concentration of $PM_{10}$. The decreased emissions seem to be the additional factor for the change in the concentration of $PM_{10}$.

Effect Verification of Wearable Assisting Wear for Increasing Golf Carry Distance (골프 비거리 증가를 위한 기능성 보조 웨어의 효과 검증)

  • Park, Yang-Sun;Woo, Byung-Hoon;Lim, Young-Tae
    • Korean Journal of Applied Biomechanics
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    • v.22 no.4
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    • pp.421-428
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    • 2012
  • The purpose of this study was to verify the effects of developed assisting wear which maximize trunk(back) muscle's stretch-shortening effect during backswing and downswing for increasing golf ball carrying distance. Design and fabrication of assistive wear were performed based on the results of analyzed data of trunk EMG activity from the golf drive swings of elite professional male golfers during back swing and downswing phases. After the prototype of wear was produced, surface EMG and Flight scope tests were conducted to verify the effectiveness of the wear for increasing distance to the professional golfers. Results indicated that wearing trial showed significant longer carry distance than the non-wearing trial(p<.001). The carry distance of wearing trial showed an average 229 m compared to the non-wearing trial, the average 225 m. The swing with wearing also produced significantly faster ball speed than the trial without wearing(p<.05). Average 245 Km/h and 244 Km/h were produced for the swing with and without wearing trails, respectively. EMG results also indicated that the muscle activity of left psoas was significantly increased for wearing trial during downswing and near the impact. Thus, this may affect positively to increase club head speed. The activity of the left latissimus dorsi was dramatically increased during the final stage of swing. This generates elongation effect for longer follow-through and increased impulse between club and ball so eventually valid assistance to increase carry distance. Therefore, the developed assisting wear was proved to be effective tool for increasing golf ball carry distance with maximizing trunk(back) muscle's stretch-shortening effect during backswing and downswing.