• Title/Summary/Keyword: loss rate

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Development of Automatic Chicken Cutting Machine

  • Woo, Duk Gam;Kim, Yeong Jin;Lim, Hack kyu;Kim, Tae Han
    • Journal of Biosystems Engineering
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    • v.43 no.4
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    • pp.386-393
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    • 2018
  • Purpose: Chicken cutting is done manually, which is inefficient, unhygienic, and carries a high accident risk during processing. This study develops and evaluates an automatic chicken cutting machine that suits small-scale workplaces. Methods: This study developed an automatic chicken cutting machine equipped with four traverse blades and two longitudinal blades. An experiment was conducted with various blade rotating speeds and tray feed rates to evaluate the machine's performance. The chicken loss rate and chicken piece weights were measured to calculate the coefficient of variation (CV), thereby determining processing uniformity. Results: The optimal cutting conditions with the smallest chicken loss rate were 0.05 m/s tray feed speed and 18.8 m/s and 16.4 m/s for the traverse and longitudinal blades, respectively. The processing ran at 55.3 chickens per hour and the chicken pieces were more uniform when using the device than for hand-work processed pieces. Conclusions: The loss rate increased in proportion to the cutting-blade rotation speed due to the high cutting rate in meat. The loss rate also increased as the tray feed speed slowed because the cutting blade pushed the chicken meat. The tray feed speed should be increased to improve the amount processed per hour.

TFRC Congestion Control for Mobile Streaming Services Based on Guaranteed Minimum Transmission Rate (모바일 스트리밍 서비스를 위한 최소전송률 보장 기반 TFRC 혼잡제어)

  • Lee, Kang Seob;Choi, Seung-Sik
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.3
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    • pp.117-124
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    • 2013
  • In this paper we propose a TFRC(TCP Friendly Rate Control) which guarantees a minimum rate in order to improve the efficiency of the previous TFRC which cannot distinguish congestion losses and wireless losses and decreases throughput both in wired and wireless networks. This TFRC technique is able to guarantee a minimum rate for video by restricting a loss event rate with packet loss probability about existing TFRC and constraining a rate reduction from the feedback timeout. When we experimented both the existing TFRC and the new one with TCP in the same network, we found that the latter is better than the former. Consequently, it shows that the proposed TFRC can improve video streaming quality using a guaranteed minimum transmission rate.

A Study on Application of Learning Loss at Labor Cost Calculation in Case of Production Break Occurrence (방산원가 노무비 산정시 생산중단에 의한 학습손실 적용방안 연구)

  • Moon, Keong-Min;Lee, Yong-Bok;Kang, Sung-Jin
    • Journal of the military operations research society of Korea
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    • v.36 no.2
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    • pp.1-10
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    • 2010
  • Learning rate is generally applied to estimate an appropriate production labor cost. Learning effect is obtained from repetitive work during the production period under 3 assumptions ; homogeneous production, same producer, quantity measure in continuous unit. However, production breaks occur frequently in Korean defense industry environment because of budget constraint and annual requirements. In this case previous learning effect can not be applied due to learning loss. This paper proposed the application of learning rate when a production break occurs in Korea defense industry. To obtain a learning loss, we surveyed various learning loss factors for different production breaks(6, 12, 18 months) from 4 defense industry companies. Then, we estimate the first unit labor hours in re-production phase after production break using Anderlohr method and Retrograde method with the result of the survey. This work is the first attempt to show a method which defines and evaluates the learning loss factors in Korean defense industry environment.

A Semi-empirical Mass-loss Rate in Short-period CVs

  • Kim, Woong-Tae;Sirotkin, Fedir V.
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.76.2-76.2
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    • 2010
  • We present the final results of our study on the mass-loss rate of donor stars in cataclysmic variables (CVs). Observed donors are oversized in comparison with those of isolated single stars of the same mass, which is thought to be a consequence of the mass loss. Using the empirical mass-radius relation of CVs and the homologous approximation for changes in effective temperature T2, orbital period P, and luminosity of the donor with the stellar radius, we find the semi-empirical mass-loss rate M2dot of CVs as a function of P. The derived M2dot is at ~10-9.5-10-10 $M\odot$/yr and depends weakly on P when P > 90 min, while it declines very rapidly towards the minimum period when P < 90 min. The semi-empirical M2dot is significantly different from, and has a less-pronounced turnaround behavior with P than suggested by previous numerical models. The semi-empirical P-M2dot relation is consistent with the angular momentum loss due to gravitational wave emission, and strongly suggests that CV secondaries with 0.075 $M\odot$ < M2 < 0.2 $M\odot$ are less than 2 Gyrs old. When applied to selected eclipsing CVs, our semi-empirical mass-loss rates are in good agreement with the accretion rates derived from the effective temperatures T1 of white dwarfs. Based on the semi-empirical M2dot, SDSS 1501 and 1433 systems that were previously identified as post-bounce CVs have yet to reach the minimal period.

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Evaluation of Heat Loss by Means of Plasma Jet Ignition during Combustion Duration in the Constant Volume Vessel (정적연소실내에서의 플라즈마 제트 점화에 대한 연소기간중의 열손실산정)

  • 김문헌;문경태;박정서;김홍성
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.2
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    • pp.96-103
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    • 2003
  • In this paper, the heat loss to the constant volume vessel wall was investigated using instantaneous heat flux sensor, schlieren visualization, pressure rise curve. And the heat loss characteristics of plasma jet ignition were compared with conventional spark ignition. In case of plasma jet ignition, the flame kernel moves toward the center of combustion vessel in the initial period of combustion, and the flame surface spread out to the vessel wall. However, in case of conventional spark ignition, the flame surface contact with combustion vessel wall in the initial period of combustion. As a result, heat loss in the combustion duration for conventional spark ignition increase faster than that of plasma jet ignition. And the combustion enhancement rate of plasma jet ignition is higher than that of conventional spark ignition, and it was found that the heat loss rate is inversely proportional to the combustion enhancement rate.

A Study of Gamma-ray Irradiation Effects on Commercially Available Single-mode Optical Fiber using Fiber Bragg Grating Sensor Systems (광섬유 브래그 격자 센서를 이용한 국내외 상용 단일모드 광섬유의 감마선 영향 연구)

  • Kim, Jong-Yeol;Lee, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.10
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    • pp.2287-2292
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    • 2012
  • In this study, $Co^{60}$ gamma-ray induced loss on Ge-doped single mode (SM) fiber has been measured. Gamma-ray is irradiated for 4 hours at the dose rate of 0.5 kGy/hr, 2 kGy/hr, 8 kGy/hr. Consequently, gamma-ray induced loss based on radiation effects in Ge-doped SM fiber occur significantly. Furthermore, dose rate effect was observed, that dose rate using the same total dose increased higher, then optical fiber loss increased more. Also annealing effect was observed, that the loss after irradiation, increased higher, then the recovery rate of loss was increased. This results are foreseen to be base data in the future radiation-hardened optical fiber study.

NOx Formation Characteristics on Heat Loss Rate for CH4/Air Premixed Flames in a Perfectly Stirred Reactor (완전혼합 반응기에서 CH4/Air 예혼합화염의 열손실율에 따른 Nox 생성특성)

  • Hwang, Cheol-Hong;Lee, Kee-Man;Kum, Sung-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.7
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    • pp.1465-1472
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    • 2009
  • The effect of heat loss rate on NOx formation of $CH_4/air$premixed flame were examined numerically in a perfectly stirred reactor. The following conclusions were drawn. Under the adiabatic wall condition, an increase in the residence time causes a remarkable increases in NOx emission. Under the heat loss conditions, however, NOx decreases significantly as the heat transfer coefficient and residence time increase. As the heat loss rate increases, Thermal NO mechanism and Re-burning NO mechanism play an important role in the NOx reduction, but Prompt NO mechanism and $N_2O$-intermediate NO mechanism lead to the increase in NOx production. Although the NOx formation is actually related to complex NOx mechanism with the changes in the heat transfer coefficient and residence time, it was found that NOx concentration can be represented by independent Thermal NO mechanism. From these results, new NOx correlation combined with the heat loss rate and residence time was suggested for predicting the NOx concentration in a practical $CH_4/air$premixed combustor.

Some Insights into the Basic QA/QC for the Greenhouse Gas Analysis: Methane and Carbon Dioxide (온실가스 기기분석의 정도관리를 위한 고려사항 연구 - CH4과 CO2를 중심으로 -)

  • Jeong, Jae-Hak;Lim, Ho-Soo;Kim, Ki-Hyun;Bae, Wi-Sup;Jeon, Eui-Chan
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.5
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    • pp.712-718
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    • 2006
  • In order to investigate the analytical uncertainties associated with sampling and analysis of major greenhouse gaseous pollutants(carbon dioxide and methane), we attempted to quantify their adsorptive loss due to the contact with the container wall(such as Tedlar bag and vial). Using the GC/FID method, some basic experimental parameters(such as reproducibility and method detection limit) have been evaluated as part of the essential QA/QC The reproducibilities of carbon dioxide and methane were estimated as 2.02 and 0.2%, respectively. In addition, method detection limits were measured as 0.61 and 0.06 ng, respectively. A test of sample loss rate has also been made for Tedlar bag and vial by assessing the absolute amount of sample loss on the wall. By transferring the samples contained in Tedlar bag to various sizes of Tedlar bags, we measured differences in the absolute loss quantity due to such transfer. In addition, we also examined such loss mechanism as a function of elapsed time and light penetration rate for vial. As results, carbon dioxide and methane have shown about 2% of sample loss due to such contact. It is also noticed that the amount of loss with vial surface is lower than that of Tedlar bag. Therefore, field collection of greenhouse gases using various container types should be made more cautiously to minimize the possibility of sample loss and bias related to such loss.

Transmission Rate-Based Overhead Monitoring for Multimedia Streaming Optimization in Wireless Networks (무선 네트워크상에서 멀티미디어 스트리밍 최적화를 위한 전송율 기반의 오버헤드 모니터링)

  • Lee, Chong-Deuk
    • Journal of Advanced Navigation Technology
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    • v.14 no.3
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    • pp.358-366
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    • 2010
  • In the wireless network the congestion and delay occurs mainly when there are too many packets for the network to process or the sender transmits more packets than the receiver can accept. The congestion and delay is the reason of packet loss which degrades the performance of multimedia streaming. This paper proposes a novel transmission rate monitoring-based optimization mechanism to optimize packet loss and to improve QoS. The proposed scheme is based on the trade-off relationship between transmission rate monitoring and overhead monitoring. For this purpose this paper processes a source rate control-based optimization which optimizes congestion and delay. Performance evaluated RED, TFRC, and the proposed mechanism. The simulation results show that the proposed mechanism is more efficient than REC(Random Early Detection) mechanism and TFRC(TCP-friendly Rate Control) mechanism in packet loss rate, throughput rate, and average response rate.

Water loss Control in DMA Monitoring System Used Wireless Technology

  • Malithong, P.;Gulphanich, S.;Suesut, T.
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.773-777
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    • 2005
  • This article is about using information technology to apply with water loss inspection system in District Metering Area (DMA). Inspector can check Flow rate and Minimum Night Flow; NMF via Smart Phone or PDA include sending SMS Alert in case the Pressure, Flow rate and NMF is over the range of controlling. This will be used as equipment to implement water loss in international proactive and can keep on water loss reduction more efficiency. The system consists of Data Logger which collects data of Flow rate from DMA Master Meter. PC is Wap Server which dial via modem in order to get data through FTP Protocal that will convert text file to Microsoft Access Database. Wappage will use xhtml language to show database on Wapbrowser and can show the result on Smart Phone or PDA by graph and table for system analysis.

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