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Intelligent Service Robotics - In this study, the goal is to efficiently and actively search for a target object in a previously unknown large-scale environment. To this end, we develop a... 相似文献
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Sensory and Physicochemical Studies of Thermally Micronized Chickpea (Cicer arietinum) and Green Lentil (Lens culinaris) Flours as Binders in Low‐Fat Beef Burgers 下载免费PDF全文
Shiva Shariati‐Ievari Donna Ryland Andrea Edel Tiffany Nicholson Miyoung Suh Michel Aliani 《Journal of food science》2016,81(5):S1230-S1242
Pulses are known to be nutritious foods but are susceptible to oxidation due to the reaction of lipoxygenase (LOX) with linolenic and linoleic acids which can lead to off flavors caused by the formation of volatile organic compounds (VOCs). Infrared micronization at 130 and 150 °C was investigated as a heat treatment to determine its effect on LOX activity and VOCs of chickpea and green lentil flour. The pulse flours were added to low‐fat beef burgers at 6% and measured for consumer acceptability and physicochemical properties. Micronization at 130 °C significantly decreased LOX activity for both flours. The lentil flour micronized at 150 °C showed a further significant decrease in LOX activity similar to that of the chickpea flour at 150 °C. The lowering of VOCs was accomplished more successfully with micronization at 130 °C for chickpea flour while micronization at 150 °C for the green lentil flour was more effective. Micronization minimally affected the characteristic fatty acid content in each flour but significantly increased omega‐3 and n‐6 fatty acids at 150 °C in burgers with lentil and chickpea flours, respectively. Burgers with green lentil flour micronized at 130 and 150 °C, and chickpea flour micronized at 150 °C were positively associated with acceptability. Micronization did not affect the shear force and cooking losses of the burgers made with both flours. Formulation of low‐fat beef burgers containing 6% micronized gluten‐free binder made from lentil and chickpea flour is possible based on favorable results for physicochemical properties and consumer acceptability. 相似文献
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Chulho Bae Taeyoon Koo Youngtak Son Kyjun Park Jongdeok Jung Seokyoun Han Myungwon Suh 《Journal of Mechanical Science and Technology》2009,23(4):1157-1168
The design and manufacture of urban transportation applications has been necessarily complicated in order to improve its safety.
Urban transportation systems have complex structures that consist of various electric, electronic, and mechanical components,
and the maintenance costs generally take up approximately 60% of the total operational costs. Therefore, it is essential to
establish a maintenance plan that takes into account both safety and cost. In considering safety and cost limitations, this
research introduces an advanced reliability centered maintenance (RCM) planning method using computational techniques, and
applies the method to a standard electric motor unit (EMU) subsystem. First, this research devises a maintenance cost function
that can reflect the current operating conditions, and maintenance characteristics, of components by generating essential
cost factors. Second, a reliability growth analysis (RGA) is performed, using the Army Material Systems Analysis Activity
(AMSAA) model, to estimate reliability indexes such as failure rate, and mean time between failures (MTBF), of a standard
EMU subsystem, and each individual component Third, two optimization processes are performed to ascertain the optimal maintenance
reliability of each component in the standard EMU subsystem. Finally, this research presents the maintenance time of each
component based on the optimal maintenance reliability provided by optimization processesand reliability indexes provided
by the RGA method.
This paper was recommended for publication in revised form by Associate Editor Dae-Eun Kim
Myung-Won Suh is a professor of Mechanical Engineering. During 1986–1988, he worked for Ford motor company as researcher. During 1989–1995,
he worked in the technical center of KIA motors. He earned a BS degree in Mechanical Engineering from Seoul National University
and an MS degree in Mechanical Engineering from KAIST, South Korea. He obtained his Doctorate at the University of Michigan,
USA, in 1989. His research areas include structure and system optimization, advanced safety vehicle and reliability analysis
& optimization.
Chul-Ho Bae is a PhD candidate at Sungkyunkwan University in Suwon, South Korea. He ac-complished fellowship work as researcher at Mississippi
State University, USA, in 2003 and 2005. He worked in Institute of Advanced Machinery and Technology (IMAT) as a Research
Assistant in 2004. He was a part time Lecturer in computer aided Mechanical Engineering of Ansan College of Technology, Suwon
Science College, and Osan College during 2004–2005. He took a BS Degree in Mechanical Design and an MS Degree in Mechanical
Engineering from the Sungkyunkwan University. His research interests include computer aided engineering, reliability engineering,
and optimization. 相似文献
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Zinc vaporization of Mn-Zn ferrites was quantitatively characterized in terms of oxygen partial pressure P O2 , temperature, grain size and sample geometry. The amount of zinc loss was measured as a function of time at various temperatures by a thermogravimetric method. The weight loss due to irreversible zinc vaporization showed a linear behavior with time and increased exponentially with temperature. The observed weight loss due to zinc evaporation at 1100°C was small, whereas a significant weight change was detected at 1200°C. The weight loss was even greater in a reducing atmosphere ( P O2 = 5 × 10−5 ). Below 1300°C, the diffusion of elemental zinc was sufficiently fast to compensate the zinc loss at the interface region, resulting in a linear dependence on time. At temperatures ≥1400°C, the weight change no longer followed the linear dependence and showed a rather parabolic behavior with a concave upward slope. The core shape and the gas flow around ferrite cores were important factors that affected the rate of zinc vaporization, but not the grain size. 相似文献
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The structure and properties of fibers prepared from copolymers of poly(ethylene terephthalate) (PET) in which 2‐methyl‐1,3‐propanediol (MPDiol® Glycol is a registered trademark of Lyondell Chemical Company) at 4, 7, 10, and 25 mol% was substituted for ethylene glycol were studied and compared with those of PET homopolymer. Filaments were melt spun over a range of spinning conditions, and some filaments that were spun at relatively low spinning speeds were subjected to hot drawing. The filaments were characterized by measurements of birefringence, differential scanning calorimetry (DSC) crystallinity, melting point, glass transition temperature, wide‐angle X‐ray diffraction patterns, boiling water shrinkage, tenacity, and elongation to break. Filaments containing 25 mol% MPDiol did not crystallize in the spinline at any spinning speed investigated, whereas the other resins did crystallize in the spinline at high spinning speeds. However, compared with PET homopolymer, increasing substitution of MPDiol reduced the rate at which the crystallinity of the melt spun filaments increased with spinning speed and reduced the ultimate crystallinity that could be achieved by high‐speed spinning. The rate of development of molecular orientation, as measured by birefringence, also decreased somewhat with increasing MPDiol content. Shrinkage in boiling water decreased at high spinning speeds as the amount of crystallinity increased; however, the shrinkage decreased more slowly with increase in spinning speed as MPDiol content increased. Tenacity also decreased slightly at any given spinning speed as MPDiol content increased, but there was no significant effect on elongation to break. The addition of MPDiol in amounts up to 7 mol% increased the maximum take‐up velocity that could be achieved at a given mass throughput. This result indicates that the use of higher spinning speeds could potentially increase the productivity of melt spun yarns. Copolymer filaments spun at low speeds were readily drawn to produce highly oriented fibers with slightly less birefringence, crystallinity, and tenacity than similarly processed PET homopolymer. Preliminary dyeing experiments showed that the incorporation of MPDiol improved the dyeability of the filaments. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2598–2606, 2003 相似文献
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Multifunctional monomers, m‐xylylenedimaleimide, p‐phenylenedimaleimide, m‐phenylenedimaleimide, and p‐phenylenedinadimide, all of which have maleimide groups, were synthesized to increase thermal and radiation stabilities. The synthesized multifunctional monomers showed good compatibility with low‐density polyethylene (LDPE). Mixtures of LDPE and these multifunctional monomers were irradiated with γ‐rays from a Co‐60 source at room temperature in a nitrogen atmosphere. The absorbed dose ranged from 0 to 160 KGy. Among these multifunctional monomers, m‐xylylenedimaleimide was the best in gel fraction enhancement. Crosslinked LDPE with m‐xylylenedimaleimide displayed a higher modulus than that of crosslinked LDPE with triallyl cyanurate. For the elongation property, LDPE with m‐xylylenedimaleimide as a multifunctional monomer showed better results than that with commercial multifunctional monomers such as triallyl cyanurate (TAC) and trimethylol propane triacrylate (TMPTA). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2339–2345, 2003 相似文献