• Title/Summary/Keyword: Receiving efficiency

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Implementation of Wireless Power Transfer Circuit by Using Magnetic Resonant Coupling Method

  • Lho, Young-Hwan
    • Journal of IKEEE
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    • v.23 no.1
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    • pp.306-309
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    • 2019
  • Wireless charging is a technology of transmitting power through an air gap to an electrical load for the purpose of energy dissemination. Compared to traditional charging with code, wireless power charging has many benefits of avoiding the hassle from connecting cables, rendering the design and fabrication of much smaller devices without the attachment of batteries, providing flexibility for devices, and enhancing energy efficiency, etc. A transmitting coil and a receiving coil for inductive coupling or magnetic resonant coupling methods are available for the near field techniques, but are not for the far field one. In this paper, the wireless power transfer (WPT) circuit by using magnetic resonant coupling method with a resonant frequency of 13.45 Mhz for the low power system is implemented to measure the power transmission efficiency in terms of mutual distance and omnidirectional angles of receiver.

Effects of Corn and Soybean Meal Types on Rumen Fermentation, Nitrogen Metabolism and Productivity in Dairy Cows

  • Shen, J.S.;Song, L.J.;Sun, H.Z.;Wang, B.;Chai, Z.;Chacher, B.;Liu, J.X.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.3
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    • pp.351-359
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    • 2015
  • Twelve multiparous Holstein dairy cows in mid-lactation were selected for a replicated $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement to investigate the effects of corn and soybean meal (SBM) types on rumen fermentation, N metabolism and lactation performance in dairy cows. Two types of corn (dry ground [DGC] and steam-flaked corn [SFC]) and two types of SBM (solvent-extracted and heat-treated SBM) with different ruminal degradation rates and extents were used to formulate four diets with the same basal ingredients. Each period lasted for 21 days, including 14 d for adaptation and 7 d for sample collection. Cows receiving SFC had a lower dry matter (DM) and total N intake than those fed DGC. However, the milk yield and milk protein yield were not influenced by the corn type, resulting in higher feed and N utilization efficiency in SFC-fed cows than those receiving DGC. Ruminal acetate concentrations was greater and total volatile fatty acids concentrations tended to be greater for cows receiving DGC relative to cows fed SFC, but milk fat content was not influenced by corn type. The SFC-fed cows had lower ruminal ammonia-N, less urea N in their blood and milk, and lower fecal N excretion than those on DGC. Compared with solvent-extracted SBM-fed cows, cows receiving heat-treated SBM had lower microbial protein yield in the rumen, but similar total tract apparent nutrient digestibility, N metabolism measurements, and productivity. Excessive supply of metabolizable protein in all diets may have caused the lack of difference in lactation performance between SBM types. Results of the present study indicated that increasing the energy degradability in the rumen could improve feed efficiency, and reduce environmental pollution.

A Study on Low Power Energy Transfer Circuits of the Non Contact Method by means of Solar Generation (태양광 발전에 의한 비접촉 방식 저 전력 에너지 전송회로에 관한 연구)

  • Hwang, Lark-Hoon;Na, Seung-Kwon;Kim, Jong-Rae;Choi, Gi-Ho;Kim, Jin-Seon
    • Journal of Advanced Navigation Technology
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    • v.18 no.1
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    • pp.35-43
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    • 2014
  • In this paper, it is about to non-contact wireless power transmission according to various conditions of self induction principle between the two planar coils at a transmission unit and a receiving unit based on the theory of wireless power transmission. The experiments are occurred in order to power transfer of noncontact method from designed wireless circuits in the primely coil and secondary coil, and the applying to Half Bridge Resonant converter transmission unit and receiving unit. and that were able to prepared circumstance to calculate of the output voltage and power source. The main power of the inductive coupling the resonant converter at the transmission unit is converted electrical energy using the solar cell module and artificial light source (halogen lamp) as a replace light and received 24 V power supply from solar power was used a input power source for the wireless power transmission device. Experimental results, to received of power is used to illuminate the lighting and to charge the battery in receiving circuit.And the wireless power transmission efficiency measured at the output side of the transmission unit is obtained about 70% to 89% compared to input power of receiving unit.In addition, efficiency were tested through ID verification method and comparing the phase difference between the voltage when foreign substances interfere with wireless power transmission.

STUDIES ON THE NUTRIENT REQUIREMENTS OF KOREAN NATIVE CATTLE I. EFFECT OF ENERGY LEVELS ON PERFORMANCE AND ENERGY INTAKE OF GROWING AND FINISHING KOREAN NATIVE CATTLE

  • Ahn, B.H.;Ahn, D.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.2 no.2
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    • pp.59-66
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    • 1989
  • Growing and finishing Korean native bulls were used to investigate the effects of different dietary energy levels on performance and energy intake. Experimental observations were made over three weight categories (200 to 250 kg, 250 to 350 kg and 350 to 450 kg). Three diets (2.4, 2.6 and 2.8 Mcal ME/kg DM) were used for each weight category. Crude protein levels of the diets were 12, 11 and 10% for the respective weight groups. Dietary energy level did not significantly affect daily body gain within a weight range but daily body gain during the entire experiment was higher (P<.05) in bulls receiving 2.6 Mcal energy diet than in those fed 2.4 and 2.8 Mcal energy diets. The following equation was developed to predict daily body gain(Y) from energy levels(X) of ration. $Y\;=\;1.3.475X\;-\;2.5949X^{2}\;-\;16.355$ Increasing energy levels significantly (P<.05) decreased daily feed intake. The following equation was developed to predict daily feed intake(Y) from energy levels(X) of ration. $Y\;=\;-30.013X\;+\;5.4401X^{2}\;+\;49.119$ Feed intake per metabolic body size during the entire feeding period ranged from 100.9 to 110.8 g and was lower in bulls fed 2.6 and 2.8 Mcal energy diets than in those fed 2.4 Mcal energy diet. Increasing energy levels significantly (P<.05) improved feed efficiency. The following equation was developed to predict feed efficiency(Y) from energy levels(X) of ration. $Y\;=\;-118.34X\;+\;22.448X^{2}\;+\;162.85$ Daily energy intake during the entire experiment ranged from 18.90 to 19.99 Mcal and there was no significant difference among energy levels. Daily energy intake per metabolic body size during the feeding period ranged from 248.6 to 260.8 kcal and was slightly higher in bulls receiving 2.8 Mcal than in those fed 2.4 and 2.6 Mcal energy diets. Energy required per kg body gain ranged from 17.25 to 19.11 Mcal and was slightly lower in bulls receiving 2.6 Mcal energy diet than in those fed 2.4 and 2.8 Mcal energy diets.

Sensorless Control for a Interior Permanent Magnet Synchronous Motor based on an Instantaneous Reactive Power (순시 무효전력을 이용한 IPM모터의 센서리스 제어)

  • Joung, Woo-Taik;Kang, Hyung-Seok;Kim, Young-Seok
    • Proceedings of the KIEE Conference
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    • 2005.07b
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    • pp.1447-1449
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    • 2005
  • An interior permanent magnet synchronous motor(IPMSM) is receiving increased attention for many industrial applications because of its high torque to inertia ratio, superior power density, and high efficiency. This paper presents algorithm for speed sensorless vector control based on an Instantaneous Reactive Power. Effectiveness or algorithm is confirmed by the experiments.

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Determinants of energy efficiency in Sub-Saharan Africa

  • Acquah, Patience Mensah;Sun, Huaping;Alemzero, David Ajene;Li, Liang
    • Asia Pacific Journal of Business Review
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    • v.5 no.2
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    • pp.19-44
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    • 2021
  • Sub Saharan Africa (SSA) is receiving increased investments in the energy sector under the belt and road initiative (BRI) project since its inception in 2013. SSA has a worse energy efficiency ratio coupled with deficient electricity access, through analysis showed varied impacts on the SSA countries due to the BRI initiative. This study dilves into the influencing factors for Energy Efficiency (EE) in 38 SSA countries, applying the probit and logit approach for 2000-2018. The Multiple-regression model shows significant results of some variables such as foreign direct investment, gross domestic product, and port infrastructure quality being significant on EE under BRI initiative countries. However, the logit and probit models produce similar results and the marginal effect for the entire variable, except energy imports that do not likely impact EE. Furthermore, the interaction of quality of port infrastructure and foreign direct investment variables produces significant results, highlighting the increased investments SSA receives under the BRI initiative in the energy and transport sectors. The model Percent correctly predicted (PCP) value was about 84%, indicating it correctly classified the variables and about 16% not classified. The study recommends EE performance standards should be incorporated on energy projects in SSA to ensure that these projects are energy efficient and decouple SSA's energy demand from economic growth. The research proffers suggestions for policy regarding the BRI initiative in SSA and the implications on sustainable energy and building a community with a shared future.

Modeling of wireless power transfer system with to dimensional transmit coil (2차원 송신코일을 가지는 무선전력전송시스템의 모델링)

  • Choi, Yongoh;Seol, Won-Gyu;Kang, Byeong-Geuk;Chung, Se-kyo
    • Proceedings of the KIPE Conference
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    • 2016.07a
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    • pp.349-350
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    • 2016
  • In the magnetically coupled wireless power transmit (WPT), the study of the multi-dimensional transmission coil to solve the low power transmission efficiency from the location of transmit coil and receiving coil is being developed. This paper, an important step in this study, presents the magnetically coupled model of the WPT system consist of the two-dimensional transmit coil and verifies by the simulation and experiment. The induced model in this paper can be used to design the WPT circuit and controller for the maximum transmission efficiency.

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Efficiency of Female-Derived Donor Cells on High Postnatal Survival in Pig Cloning

  • Cho, Seong-Keun;Park, Mi-Rung;Kwon, Deug-Nam;Hwang, Kyu-Chan;Lee, Eun-Kyeong;Son, Woo-Jin;Kim, Jin-Hoi
    • Proceedings of the KSAR Conference
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    • 2004.06a
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    • pp.217-217
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    • 2004
  • The present study was conducted to investigate the developmental competency between male- and female-somatic cell derived nuclear-transferred porcine embryos, and the productive and survival efficiency of cloned male and female piglets. The potential of eggs receiving somatic cells to develop into blastocysts was not different among donor cells of different origins. (omitted)

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Data hiding in partially encrypted HEVC video

  • Xu, Dawen
    • ETRI Journal
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    • v.42 no.3
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    • pp.446-458
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    • 2020
  • In this study, an efficient scheme for hiding data directly in partially encrypted versions of high efficiency video coding (HEVC) videos is proposed. The content owner uses stream cipher to selectively encrypt some HEVC-CABAC bin strings in a format-compliant manner. Then, the data hider embeds the secret message into the encrypted HEVC videos using the specific coefficient modification technique. Consequently, it can be used in third-party computing environments (more generally, cloud computing). For security and privacy purposes, service providers cannot access the visual content of the host video. As the coefficient is only slightly modified, the quality of the decrypted video is satisfactory. The encrypted and marked bitstreams meet the requirements of format compatibility, and have the same bit rate. At the receiving end, data extraction can be performed in the encrypted domain or decrypted domain that can be adapted to different application scenarios. Several standard video sequences with different resolutions and contents have been used for experimental evaluation.

Suggestion to Improve Power Efficiency by Changing Sleep-Wakeup Period in Wireless Network Environment for Internet of things

  • Woo, Eun-Ju;Moon, Yu-Sung;Choi, Jae-Hyun;Kim, Jae-Hoon;Kim, Jung-Won
    • Journal of IKEEE
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    • v.22 no.3
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    • pp.862-865
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    • 2018
  • The proposed scheme minimizes the Idle time under the residual energy of the sensor node to adjust the Sleep-Wakeup period and minimize unnecessary energy consumption. It is The proposed scheme minimizes the Idle time under the residual energy of the sensor node to adjust the Sleep-Wakeup period and minimize unnecessary energy consumption. It is an important process to control the Application Packet Framework including the PHY and the MAC layer at each node's Idle time with the Idle time mechanism state before the proposed function is executed. The Current Control Level of the Report Attribute is fixed at one sending / receiving node where power consumption can occur, by changing Sleep-Wakeup time, the low power consumption efficiency was improved while satisfying the transmission requirement of the given delay time constraint.