• Title/Summary/Keyword: transmission velocity

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On the vibration influence to the running power plant facilities when the foundation excavated of the cautious blasting works. (노천굴착에서 발파진동의 크기를 감량 시키기 위한 정밀파실험식)

  • Huh Ginn
    • Explosives and Blasting
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    • v.9 no.1
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    • pp.3-13
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    • 1991
  • The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ${\phi}70mm$ on the calcalious sand stone (soft -modelate -semi hard Rock). The total numbers of test blast were 88. Scale distance were induced 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagtion Law in Blasting Vibration $V=K(\frac{D}{W^b})^n$ were V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum charge per delay-period of eight milliseconds or more (kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents where the quantity $\frac{D}{W^b}$ is known as the scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagorized in three groups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge Per delay Plots of peak particle velocity versus distoance were made on log-log coordinates. The data are grouped by test and P.P.V. The linear grouping of the data permits their representation by an equation of the form ; $V=K(\frac{D}{W^{\frac{1}{3}})^{-n}$ The value of K(41 or 124) and n(1.41 or 1.66) were determined for each set of data by the method of least squores. Statistical tests showed that a common slope, n, could be used for all data of a given components. Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom over loom distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m ------- under l00m ${\cdots\cdots\cdots}{\;}41(D/sqrt[2]{W})^{-1.41}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}A$ Over 100m ${\cdots\cdots\cdots\cdots\cdots}{\;}121(D/sqrt[3]{W})^{-1.66}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}B$ where ; V is peak particle velocity In cm / sec D is distance in m and W, maximLlm charge weight per day in kg K value on the above equation has to be more specified for further understaring about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

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Emotion fusion video communication services for real-time avatar matching technology (영상통신 감성융합 서비스를 위한 실시간 아바타 정합기술)

  • Oh, Dong Sik;Kang, Jun Ku;Sin, Min Ho
    • Journal of Digital Convergence
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    • v.10 no.10
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    • pp.283-288
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    • 2012
  • 3D is the one of the current world in the spotlight as part of the future earnings of the business sector. Existing flat 2D and stereoscopic 3D to change the 3D shape and texture make walking along the dimension of the real world and the virtual reality world by making it feel contemporary reality of coexistence good show. 3D for the interest of the people has been spreading throughout the movie which is based on a 3D Avata. 3D TV market of the current conglomerate of changes in the market pioneer in the 3D market, further leap into the era of the upgrade was. At the same time, however, the modern man of the world, if becoming a necessity in the smartphone craze new innovation in the IT market mobile phone market and also has made. A small computer called a smartphone enough, the ripple velocity and the aftermath of the innovation of the telephone, the Internet as much as to leave many issues. Smartphone smart phone is a mobile phone that can be several functions. The current iPhone, Android. In addition to a large number of Windows Phone smartphones are released. Above the overall prospects of the future and a business service model for 3D facial expression as input avatar virtual 3D character on camera on your smartphone camera to recognize a user's emotional expressions on the face of the person is able to synthetic synthesized avatars in real-time to other mobile phone users matching, transmission, and be able to communicate in real-time sensibility fused video communication services to the development of applications.

Analysis of Capillary Flow in Open-Top Rectangular Microchannel (상판이 없는 직사각형 단면의 미세채널에서 모세관 유동 분석)

  • Park, Eun-Jung;Cho, Ji-Yong;Kim, Jeong-Chul;Hur, Dae-Sung;Chung, Chan-Il;Kim, Jung-Kyung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.1
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    • pp.77-82
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    • 2010
  • Our study aims to understand the flow of liquid in an open-top rectangular microchannel that can be used in micro total analysis systems ($\mu$-TAS) because it has advantages in terms of light transmission and energy efficiency. We measured the liquid velocity using particle tracking technique and conducted a simulation with computational fluid dynamics by altering the area of channel cross section and channel length for the capillary-driven flow in the open-top rectangular microchannel. When liquid water drops to an entrance of the fabricated microchannel with a height of 20 μm and a width of 20 ${\mu}m$, it flows along the microchannel by only capillary force. In the wetting behavior of the liquid, important parameters of this flow are channel size, contact angle and liquid properties such as surface tension and viscosity, which are used to control the flow of liquid in the microchannel.

Study on Vehicle Deceleration Control in School Zones by Taking Driver's Comfort into Account (스쿨 존에서 운전자의 승차감을 수반한 차량 감속 제어에 관한 연구)

  • Cho, Hyo-Seung;Kim, Hyoung-Seok;Lee, Byung-Ryong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.10
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    • pp.1359-1366
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    • 2010
  • Recently, many electronic control techniques for vehicles have been developed and applied. One of the technologies can be X-by-wire such as throttle-by-wire, brake-by-wire, steer-by-wire, and etc, in which most of mechanical parts are replaced into electrical wire and actuators. In this study, the effect of throttle-by-wire and brake-by-wire control systems on vehicle velocity control, especially in a school zone, are taken into consideration. The number of accidents reported in school zones is higher than that in other places. The reason for this is that many vehicle drivers do not obey speed limit regulations. Moreover, some of the students are careless while crossing the streets. Therefore, in this study, we attempt to develop a method using throttle-by-wire and brake-by-wire control systems for automatically reducing the vehicle speed such that it will be within the speed limit. First, an engine model and a transmission system model are developed for a specific vehicle model. Second, speed reduction is carried out such that the reduction follows a pre-designed cubic spline trajectory; the trajectory is determined such that rapid deceleration, which causes discomfort to the driver and passengers, can be prevented, for which a fuzzy-PID control algorithm is applied for the trajectory following control. Finally, simulation results are presented to verify the performance of the proposed speed reduction control system.

Accelerated Degradation Test and Failure Analysis of Rapid Curing Epoxy Resin for Restoration of Cultural Heritage (문화재 복원용 속(速)경화형 Epoxy계 수지의 가속열화시험 및 고장분석 연구)

  • Nam, Byeong Jik;Jang, Sung Yoon
    • Journal of Conservation Science
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    • v.33 no.6
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    • pp.467-483
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    • 2017
  • In this study, the degradation properties by temperature stress of $Araldite^{(R)}$ rapid-curing epoxy resin used for inorganic cultural heritages, was identified. The tensile and tensile shear strength of durability decreased for 12,624 hours at temperatures of $40{\sim}60^{\circ}C$. In terms of stability of external stress and temperature, the slow-curing epoxy was superior to the rapid-curing epoxy, and cultural heritage conservation plans should therefore consider the strength and stress properties of restoration materials. Color differences increased for 12,624 hours at temperatures of $40{\sim}60^{\circ}C$, and glossiness decreased. Both color and gloss stability were weak, which necessitates the improvement of optical properties. Thermal properties (weight loss, decomposition temperature, and glass transition temperature) of adhesives are linked to mechanical properties. Interfacial properties of the adherend and water vapor transmission rates of adhesives are linked to performance variation. For porous media (ceramics, brick, and stone), isothermal and isohumid environments are important. For outdoor artifacts on display in museums, changes in physical properties by exposure to varying environmental conditions need to be minimized. These results can be used as baseline data in the study of the degradation velocity and lifetime prediction of rapid-curing epoxy resin for the restoration of cultural heritages.

The Design of the Class E Swiching Frequency Multiplier (스위칭 모드 E급 주파수 체배기 설계)

  • Roh, Hee-Jung;Seo, Choon-Weon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.10
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    • pp.90-99
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    • 2009
  • In this paper, we proposed the new class-E frequency multiplier design that include the highest efficient characteristics. The proposed frequency multiplier is designed for 5.8[GHz] output using the frequency multiplier about 2.9[GHz] input signal. And studying in this paper is for the design and the implementation of the class E frequency multiplier. For the result, the maximum highest efficient characteristics 32[%] which is with output power 24.5[dBm] and 8.5[dB], is shown with frequency multiplier for the 2.9/5.8[GHz] class E. And we applied the linear method to the implemented class E frequency multiplier. As a result, the output spectrum for the linear is upgrade to 12[dB], 12[dB], 13[dB] of the ACPR characteristics on the +11[MHz], +20[MHz], +30[MHz] offset frequency in the center frequency. The result is satisfied with the 3.83[%] of the lineared EVM for the 64-QAM modulated method with the 54[Mbps] transmission velocity. In this paper, we show that the good compensation result of the linearity and the efficiency through the digital pre-linear method of the distortion with the frequency multiplier. Therefore, we suggested the frequency multiplier method are applying to WLAN, cellular, PCS, WCDMA, and etc.

A Study on Detection of Phase Error due to the Doppler Effect with Coding Techniques in Mobile Satellite Communication Network on Interference and Fading Environments (간섭과 페이딩 환경하에서 이동위성 통신망에 부호화 기법을 이용한 도플러 효과에 의한 위상에러 검출에 관한 연구)

  • Cho, Hun-Ju;Kang, Heau-Jo;Choi, Yong-Seok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.7 no.2
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    • pp.128-138
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    • 1996
  • In this paper, the Doppler phase error due to the relative velocity between a satellite and the earth station in communications using a low earth orbit mobile satellite is detected. The performance of BPSK system in the presence of Rician fading channel environment with Doppler phase error, inter- ference and noise is compared with that of the system disturbed by Doppler phase error and noise only, And adopted coding techniques are Hamming, BCH, RS and convolution codes. The expression of error rate performance of BPSK system is derived as the type of complementary error function. The main conclusion that can be drawn from this analysis is that Rician fading channel environment with Do- ppler phase error and interference, noise effect yields severe performance degradation then Doppler phase error and noise effect in satellite communication channel. The conclusion can be drawn from this analysis is that using coding technique then noncoding. And using the numerical calculation, we give a quantitative insight how much the satellite communication channel parameters degrade the system per- formance. Furthermore it is shown that an appropriate transmission power control for the performance enhancement is beneficial to the new satellite communication system planning.

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Effects of Joint Mobilization Techniques on the Joint Receptors (관절 가동운동(mobilization)이 관절 감수기(joint receptors)에 미치는 영향)

  • Kim, Suhn-Yeop
    • Physical Therapy Korea
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    • v.3 no.2
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    • pp.95-105
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    • 1996
  • Type I, II, III are regarded as "true" joint receptors, type IV is considered a class of pain receptor. Type I, II and III mechanoreceptors, via static and dynamic input, signal joint position, intraarticular pressure changes, and the direction, amplitude, and velocity of joint movements. Type I mechanoreceptor subserve both static and dynamic physiologic functions. Type I are found primarily in the stratum fibrosum of the joint capsule and ligaments. Type I receptors have a low threshold for activation and are allow to adapt to changes altering their firing frequency. Type II receptors have a low threshold for activation. These dynamic receptors respond to joint movement. Type II receptors are thus termed rapidly adapting. Type II joint receptors are located at the junction of the synovial membrane and fibrosum of the joint capsule and intraarticular and extraarticular fat pads. Type III receptors have been found in collateral ligaments of the joints of the extremities. Morphologically similar to Golgi tendon organ. These dynamic receptors have a high threshold to stimulation and are slowly adating. Type IV receptors possess free nerve ending that have been found in joint capsule and fat pads. They are not normally active, but respond to extreme mechanical deformation of the joint as well as to direct chemical or mechanical irritation. Small amplitude oscillatory and distraction movements(joint mobilization) techniques are used to stimulate the mechanoreceptors that may inhibit the transmission of nociceptors stimuli at the spinal cord or brain stem levels.

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Effects of Joint Mobilization Techniques on the Joint Receptors (관절 가동운동이 관절 감수기에 미치는 영향)

  • Kim, Suhn-Yeop
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.2 no.1
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    • pp.9-19
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    • 1996
  • Type I, II, III are regarded as "true" joint receptors, type IV is considered a class of pain receptor. Type I, II and III mechanoreceptors, via static and dynamic input, signal joint position, intraarticular pressure changes, and the direction, amplitude, and velocity of joint movements. Type I mechanoreceptor subserve both static and dynamic physiologic functions. Type I are found primarily in the stratum fibrosum of the joint capsule and ligaments. Type I receptors have a low threshold for activation and are allow to adapt to changes altering their firing frequency. Type II receptors have a low threshold for activation. These dynamic receptors respond to joint movement. Type II receptors are thus termed rapidly adapting. Type II joint receptors are located at the junction of the synovial membrane and fibrosum of the joint capsule and intraarticular and extraarticular fat pads. Type III receptors have been found in collateral ligaments of the joints of the extremities. Morphologically similar to Golgi tendon organ. These dynamic receptors have a high threshold to stimulation and are slowly adating. Type IV receptors possess free nerve ending that have been found in joint capsule and fat pads. They are not normally active, but respond to extreme mechanical deformation of the joint as well as to direct chemical or mechanical irritation. Small amplitude oscillatory and distraction movements(joint mobilization) techniques are used to stimulate the mechanoreceptors that may inhibit the transmission of nociceptors stimuli at the spinal cord or brain stem levels.

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A Study on the Formation of Hydrate Plugging due to water molecules in High Pressure and Low Temperature Gas Pipeline (고압$\cdot$저온 가스 배관에서 수분에 의한 하이드레이트 플러깅 형성)

  • Lee J. H.;Baek Y. S.;Sung W. M.
    • Journal of the Korean Institute of Gas
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    • v.6 no.1 s.17
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    • pp.38-45
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    • 2002
  • Hydrates are solid cryctallines resembling ice in appearance, which are consist of a gas molecule surrounded by a cage of water molecules. Because of containning a large amount of methane, hydrates have been considered as a future energy resource. However, the formation of hydrates in the oil and gas industries has been known as a serious problem for a long time. The formation of hydrate in pipeline is common in seasonally cold or sub-sea environments with low temperatures and high pressures. Especially, hydrate plug formation becomes a real menace to flow assurance in inadequately protected transmission lines. This study was carried out for the purpose of understanding mechanism of hydrate plugging and examining formation conditions of hydrate in high pressure gas pipeline. In this study, we measured hydrate equilibrium conditions under the various flowing conditions with the methane. The results were presented both the plugging tendency and the effect of flowing velocity.

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