• Title/Summary/Keyword: due-date

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Dietary manipulation: a sustainable way to mitigate methane emissions from ruminants

  • Haque, Md Najmul
    • Journal of Animal Science and Technology
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    • v.60 no.6
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    • pp.15.1-15.10
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    • 2018
  • Methane emission from the enteric fermentation of ruminant livestock is a main source of greenhouse gas (GHG) emission and a major concern for global warming. Methane emission is also associated with dietary energy lose; hence, reduce feed efficiency. Due to the negative environmental impacts, methane mitigation has come forward in last few decades. To date numerous efforts were made in order to reduce methane emission from ruminants. No table mitigation approaches are rumen manipulation, alteration of rumen fermentation, modification of rumen microbial biodiversity by different means and rarely by animal manipulations. However, a comprehensive exploration for a sustainable methane mitigation approach is still lacking. Dietary modification is directly linked to changes in the rumen fermentation pattern and types of end products. Studies showed that changing fermentation pattern is one of the most effective ways of methane abatement. Desirable dietary changes provide two fold benefits i.e. improve production and reduce GHG emissions. Therefore, the aim of this review is to discuss biology of methane emission from ruminants and its mitigation through dietary manipulation.

Prediction of the Logitudinal Aerodynamic Coefficients of the Aircraft at Low Speed (항공기 저속 세로축 공력 계수 예측에 관한 연구)

  • Kang, Jung-Hoon
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.8 no.1
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    • pp.83-95
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    • 2000
  • Lift, drag, pitching moment, what we call longitudinal aerodynamic coefficient, effects airplanes directly, so the method to find the accurate result quickly is an important factor from the beginning of the aircraft design. There are different ways to find aerodynamic coefficient such as empirical methods, numerical analysis methods, wind tunnel tests, and finally through an actual flight tests, but choosing the best methods depends on the due date or the cost. The accuracy varies on each design level, but all this methods have relationship to complement and balance each other, so by combining proper methods, the best result can be obtained. At this paper, empirical methods and numerical analysis method were experimented, compared, and reviewed to find the availability of each method and by combining two methods accurate result was obtained. So, we applied this methods to predict the aerodynamic coefficient on cruise configuration aircraft, and was able to obtain more accurate result on the low speed longitudinal aerodynamic coefficient. Also by watching there result, we are able to predict the errors before the actual wind tunnel test.

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Analysis of Progress Schedule and Delay Element of Frame Works in Apartments (아파트 구체공사의 공정관리 및 공기지연요소 분석에 관한 연구)

  • 최은준;최민권;조형근
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.05a
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    • pp.157-160
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    • 2003
  • In order to reduce the construction cost and period without degrading the quality, construction companies are making a lot of efforts to prefabricate and mechanize the construction process, and introducing and utilizing various techniques of construction time management in the process of construction. However, due to the various factors (such as weather conditions, labor factors, supply of equipment and materials, safety accident, etc) in the process of construction, construction projects are not frequently completed within the scheduled Period. This research is to examine the current status of construction time management and factors causing delay in construction with regard to the concrete work (such as form work, steel reinforcement, and concrete work) in building apartments.

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Probing Tidal Field Strength of Virgo Cluster Galaxies

  • Yoon, Hye-In;Chung, Ae-Ree
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.74.2-74.2
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    • 2011
  • We probe the tidal perturbation parameter f of Virgo cluster galaxies. The goal is to measure the strength of tidal fields around individual galaxies to get better understanding gravitational processes that can affect galaxy evolution in the cluster environment. The f-value is defined as a logarithmic ratio between the net internal gravitational force within a galaxy and the external tidal force exerted by a neighboring galaxy. Hence, it provides one way to quantify the tidal field strength of galaxies, in particular, due to galaxy neighbors. In this study, we determine f-values of the VIVA galaxies, samples of the VLA Imaging study of Virgo galaxies in Atomic gas, using the Extended Virgo Cluster Catalog (EVCC) which is the most complete Virgo cluster catalog to date. With diagnostics based on the HI gas and R-band morphologies, we discuss the impact of the tidal fields on the evolution of the VIVA sample. Also, we compare the tidal field strength to the intra cluster medium (ICM) pressure for each sample galaxy to pin down environmental processes at work.

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Microwave heating of carbon-based solid materials

  • Kim, Teawon;Lee, Jaegeun;Lee, Kun-Hong
    • Carbon letters
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    • v.15 no.1
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    • pp.15-24
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    • 2014
  • As a part of the electromagnetic spectrum, microwaves heat materials fast and efficiently via direct energy transfer, while conventional heating methods rely on conduction and convection. To date, the use of microwave heating in the research of carbon-based materials has been mainly limited to liquid solutions. However, more rapid and efficient heating is possible in electron-rich solid materials, because the target materials absorb the energy of microwaves effectively and exclusively. Carbon-based solid materials are suitable for microwave-heating due to the delocalized pi electrons from sp2-hybridized carbon networks. In this perspective review, research on the microwave heating of carbon-based solid materials is extensively investigated. This review includes basic theories of microwave heating, and applications in carbon nanotubes, graphite and other carbon-based materials. Finally, priority issues are discussed for the advanced use of microwave heating, which have been poorly understood so far: heating mechanism, temperature control, and penetration depth.

Bio-inspired self powered nervous system for civil structures

  • Shoureshi, Rahmat A.;Lim, Sun W.
    • Smart Structures and Systems
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    • v.5 no.2
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    • pp.139-152
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    • 2009
  • Globally, civil infrastructures are deteriorating at an alarming rate caused by overuse, overloading, aging, damage or failure due to natural or man-made hazards. With such a vast network of deteriorating infrastructure, there is a growing interest in continuous monitoring technologies. In order to provide a true distributed sensor and control system for civil structures, we are developing a Structural Nervous System that mimics key attributes of a human nervous system. This nervous system is made up of building blocks that are designed based on mechanoreceptors as a fundamentally new approach for the development of a structural health monitoring and diagnostic system that utilizes the recently developed piezo-fibers capable of sensing and actuation. In particular, our research has been focused on producing a sensory nervous system for civil structures by using piezo-fibers as sensory receptors, nerve fibers, neuronal pools, and spinocervical tract to the nodal and central processing units. This paper presents up to date results of our research, including the design and analysis of the structural nervous system.

-CTP System Study for Customer Reliability Improvement through Due date Promising- (납기확약을 통해 고객 신뢰성 향상을 도모하기 위한 CTP 시스템에 관한 연구)

  • Oh Sung Hwan;Park Young Ki;Kang Kyong Sik
    • Journal of the Korea Safety Management & Science
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    • v.6 no.3
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    • pp.121-130
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    • 2004
  • This Study will introduce the concept of CTP(Capable-to-Promise) Algorithm, CTP process, and the modeling of algorithm. This research is based on the environment of using Job-Shop method. CTP algorithm model use LPST(Latest Possible Start Time) and EPST(Earliest Possible Start Time) method especially. It is important part of executing CTP system. The CTP modeling and implementing develops to system which is able to implement in the various business environment through additional and continuous research.

Modeling Due-date Promising system using CTP Algorithm in SCM Environment (공급망상에세 CTP 알고리즘을 이용한 납기확약 시스템 모델링)

  • 최진;박상민;남호기;이종천
    • Proceedings of the Safety Management and Science Conference
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    • 2003.11a
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    • pp.117-127
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    • 2003
  • This Study will introduce the concept of ATP(Available To Promise) and CTP(Capable to Promise) through the existing study , the process analysis of CTP(Capable to Promise), the modeling of algorithm and the embodiment of system. This research considers the environment of using Job-Shop method. The CTP algorithm models espicially through using LPST(Latest Possible Start Time) and EPST(Earlist Possible Start Time) method. It is important part of executing CTP(Capable to Promise), The CTP(Capable to Promise) modeling and implementing system develops to system which is capable to implement in the various business environment through addational and continuous research.

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A Framework of Web-based Inventory System using a RFID in Plastic Injection Molding Industry (플라스틱 사출산업의 RFID를 이용한 웹기반 재고관리시스템 프레임웤)

  • Lim, Seok-Jin;Song, Jae-Ho;Ko, Young-Uk;Park, Byong-Tae
    • Proceedings of the Safety Management and Science Conference
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    • 2010.04a
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    • pp.189-197
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    • 2010
  • Recently, industrial business environments have rapidly changed and face severe competitive challenges. The effective inventory system enables to product and deliver the products quickly for meeting due date of customer's order in this environment. This study have developed a web-based inventory system framework using RFID for a plastic injection molding industry. The system analysis inventory problem issues such as inventory planning, warehouse assignment. In this study, web-based inventory system using Java language is proposed and implemented. As the result of implementation of the system, we expected that it manages to inventory planning continually and systematically.

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A Study of Rivulet Flow on an Inclined Solid Surface (경사면에서의 리뷸릿 유동에 관한 연구)

  • 김진호;김호영;강병하;이재헌
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.10
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    • pp.1042-1048
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    • 2001
  • When a liquid is supplied through a nozzle onto a relatively non-wetting inclined solid surface, a narrow rivulet forms. This work provides novel physical insights into the following phenomena in the rivulet flow that have not been well understood to date. Firstly, the fundamental mechanism behind the transition of a linear rivulet to a droplet flow is investigated. The experiments show that the droplet flow emerges due to the necking of a liquid thread near the nozzle. Based on the observation, it is argued that when the axial velocity of a liquid is slower than the retraction velocity of its thread, the bifurcation of the liquid thread occurs, and this argument is experimentally verified. Secondly, a discussion on the curled motion of a meandering rivulet is given. This study proposes the contact angle hysteresis as a primary origin of the centripetal force that enables the rivulet\`s curved motion. A simple scaling analysis based on this assumption predicts a radius of curvature which agrees with the experimental observation.

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