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101.
Effects of boiling, warm-holding, mashing and cooling on the levels of enzyme-resistant potato starch 总被引:1,自引:0,他引:1
Ronan Gormley & Thomas Walshe 《International Journal of Food Science & Technology》1999,34(3):281-286
Summary The effects of boiling, warm-holding, cooling and mashing on the enzyme-resistant starch (ERS) content of potatoes was studied together with inter-tuber and inter-cultivar variation in ERS content. Inter-tuber variation in ERS content was small and mean values (on a dry matter basis) for boiled and raw potatoes were 10.7 and 74.2% (cultivar Rooster) and 10.8 and 74.3% (cultivar Anna). There was no significant difference between the ERS values of boiled potatoes of seven cultivars (range 10.0–10.8%). Warm-holding mashed potatoes at 65–70 °C for 1 hr raised ERS values from 2.20 to 4.80%. In a separate test slow cooling over 2 hr to 21 °C raised the ERS content from 3.65 to 6.35%. Multiple cook-cool (3×) gave ERS contents of 23.2 and 18.2% for boiled potatoes held for 24 hr at 4 or 20 °C. Mashing and freezing raised ERS values by 1–2%. 相似文献
102.
The N-Queens Puzzle is a fascinating combinatorial problem. Up to now, the number of distinct valid placements of N non-attacking queens on a generalized N × N chessboard cannot be computed by a formula. The computation of these numbers is instead based on an exhaustive search whose complexity grows dramatically with the problem size N. Solutions counts are currently known for all N up to 26. The parallelization of the search for solutions is embarrassingly simple. It is achieved by pre-placing the queens within a certain board region. These pre-placements partition the search space. The chosen extent of the pre-placement allows for a wide range of the partitioning granularity. This ease of partitioning makes the N-Queens Puzzle a great show-off case for tremendously parallel computation approaches and a flexible benchmark for parallel compute resources. This article presents the Q27 Project, an open-source effort targeting the computation of the solution count of the 27-Queens Puzzle. It is the first undertaking pushing the frontier of the N-Queens Puzzle that exploits the complete symmetry group D 4 of the square. This reduces the overall computational complexity already to an eighth in comparison to a naive exploration of the whole search space. This article details the coronal pre-placement that enables the partitioning of the overall search under this approach. With respect to the physical implementation of the computation, it describes the hardware structure that explores the resulting subproblems efficiently by exploiting bit-level operations and their mapping to FPGA devices as well as the infrastructure that organizes the contributing devices in a distributed computation. The performance of several FPGA platforms is evaluated using the Q27 computation as a benchmark, and some intriguing observations obtained from the available partial solutions are presented. Finally, an estimate on the remaining run time and on the expected magnitude of the final result is dared. 相似文献
103.
Base station placement has significant impact on sensor network performance. Despite its significance, results on this problem
remain limited, particularly theoretical results that can provide performance guarantee. This paper proposes a set of procedure
to design (1− ε) approximation algorithms for base station placement problems under any desired small error bound ε > 0. It
offers a general framework to transform infinite search space to a finite-element search space with performance guarantee.
We apply this procedure to solve two practical problems. In the first problem where the objective is to maximize network lifetime,
an approximation algorithm designed through this procedure offers 1/ε2 complexity reduction when compared to a state-of-the-art algorithm. This represents the best known result to this problem.
In the second problem, we apply the design procedure to address base station placement problem when the optimization objective
is to maximize network capacity. Our (1− ε) approximation algorithm is the first theoretical result on this problem.
Yi Shi received his B.S. degree from University of
Science and Technology of China, Hefei, China, in 1998, a M.S. degree from Institute of Software, Chinese Academy of Science,
Beijing, China, in 2001, and a second M.S. degree from Virginia Tech, Blacksburg, VA, in 2003, all in computer science. He
is currently working toward his Ph.D. degree in electrical and computer engineering at Virginia Tech. While in undergraduate,
he was a recipient of Meritorious Award in International Mathematical Contest in Modeling and 1997 and 1998, respectively.
His current research focuses on algorithms and optimizations for wireless sensor networks, wireless ad hoc networks, UWB-based
networks, and SDR-based networks. His work has appeared in journals and highly selective international conferences (ACM Mobicom, ACM Mobihoc, and IEEE Infocom).
Y. Thomas Hou received the B.E. degree from the City College of New York in 1991, the M.S. degree from Columbia University in 1993, and
the Ph.D. degree from Polytechnic University, Brooklyn, New York, in 1998, all in Electrical Engineering.
Since Fall 2002, he has been an Assistant Professor at Virginia Tech, the Bradley Department of Electrical and Computer Engineering,
Blacksburg, VA. His current research interests are radio resource (spectrum) management and networking for software-defined
radio wireless networks, optimization and algorithm design for wireless ad hoc and sensor networks, and video communications
over dynamic ad hoc networks. From 1997 to 2002, Dr. Hou was a Researcher at Fujitsu Laboratories of America, Sunnyvale, CA,
where he worked on scalable architectures, protocols, and implementations for differentiated services Internet, service overlay
networking, video streaming, and network bandwidth allocation policies and distributed flow control algorithms.
Prof. Hou is a recipient of an Office of Naval Research (ONR) Young Investigator Award (2003) and a National Science Foundation
(NSF) CAREER Award (2004). He is a Co-Chair of Technical Program Committee of the Second International Conference on Cognitive
Radio Oriented Wireless Networks and Communications (CROWNCOM 2007), Orlando, FL, August 1–3, 2007. He also was the Chair
of the First IEEE Workshop on Networking Technologies for Software Defined Radio Networks, September 25, 2006, Reston, VA.
Prof. Hou holds two U.S. patents and has three more pending.
Alon Efrat earned his Bachelor in Applied Mathematics from the Technion (Israel’s Institute of Technology) in 1991, his Master in Computer
Science from the Technion in 1993, and his Ph.D in Computer Science from Tel-Aviv University in 1998. During 1998–2000 he
was a Post Doctorate Research Associate at the Computer Science Department of Stanford University, and at IBM Almaden Research
Center. Since 2000, he is an assistant professor at the Computer Science Department of the University of Arizona. His main
research areas are Computational Geometry, and its applications to sensor networks and medical imaging. 相似文献
104.
Brett P.N. Harrison A.J. Thomas T.A. 《IEEE transactions on information technology in biomedicine》2000,4(1):30-36
Precise control of automated invasive surgical tools requires real-time identification of tissue types and their deformation. At the focus of this paper is the epidural puncture, for which it is shown that the tissue type and deformation can respectively be determined from laser-based spectroscopy and the change in force required to push the needle through the various tissues. Studies have shown that physiological variations from one patient to another are too great to allow absolute values to be reliably used to indicate the position of the needle tip. However, the pattern of force variation during penetration is shown to be similar between specimens. Interpretation of this information in conjunction with spectroscopic techniques can be used to discriminate between tissues and tissue structure at the needle tip. This paper describes results from an investigation on automatic techniques for interpreting the type and deformation of tissues under tool action 相似文献
105.
Secure and trusted Information and Communication Technology (ICT) infrastructures are key enablers for the development of a trustworthy Information Society. The European Union, recognising this, has launched over the last few years a number of research initiatives aiming at designing and building secure and dependable ICT systems and networks, which respect citizens’ rights and protect their privacy and personal data. The European Commission is already funding more than 37 R&D projects in this area under the IST programme, which is part of the 6th Framework Programme (2002 to 2006). The paper first presents the main research challenges in the development of secure, dependable and trusted ICT infrastructures. It then describes a representative set of these IST projects dealing with advanced research in network and service security. The paper also presents upcoming opportunities for research funding in this area under the newly launched ICT programme, part of the 7th Framework Programme that extends from 2007 to 2013. 相似文献
106.
A Complete Model for Simulating Magnitude and Phase of Emissions from a DUT Placed Inside a GTEM Cell 总被引:1,自引:0,他引:1
Ngu X.T.I. Nothofer A. Thomas D.W.P. Christopoulos C. 《Electromagnetic Compatibility, IEEE Transactions on》2007,49(2):285-293
Since the publication of IEC 61000-4-20, the gigahertz transverse electromagnetic (GTEM) cell has gained popularity in radiated emission and immunity electromagnetic compatibility tests. Various numerical methods such as finite-difference time-domain, finite element method, and method of moments have been used to model the GTEM cell in the pursuit of getting to know the characteristic of the GTEM cell with varying degrees of verification. In this paper, the time-domain transmission line model will be used to model the GTEM cell. The advantages of this method include high accuracy and the ability to model different materials. Thus, the GTEM is realistically modeled including radio absorbing material (RAM) and lumped terminations. In addition, the model of a realistic device under test (DUT) was also included in the GTEM model. The DUT consists of a standard sized box with an aperture, placed in different orientations inside the GTEM for power and phase measurements. The particular features of this paper are: 1) the inclusion of a realistic numerical model of RAM, 2) the inclusion of a realistic DUT model, 3) systematic verification of the model against measurements, and 4) the method of phase measurement in a GTEM cell. Good agreement between the experimental results and simulations is obtained. 相似文献
107.
Achim Streit Piotr Bala Alexander Beck-Ratzka Krzysztof Benedyczak Sandra Bergmann Rebecca Breu Jason Milad Daivandy Bastian Demuth Anastasia Eifer André Giesler Björn Hagemeier Sonja Holl Valentina Huber Nadine Lamla Daniel Mallmann Ahmed Shiraz Memon Mohammad Shahbaz Memon Michael Rambadt Morris Riedel Mathilde Romberg Bernd Schuller Tobias Schlauch Andreas Schreiber Thomas Soddemann Wolfgang Ziegler 《电信纪事》2010,65(11-12):757-762
UNICORE is a European Grid Technology with more than 10 years of history. Originating from the Supercomputing domain, the latest version UNICORE 6 has turned into a general-purpose Grid technology that follows established standards and offers a rich set of features to its users. The paper starts with an architectural insight into UNICORE 6, highlighting the workflow features, standards and the different clients. Next, the current state of advancement is presented by describing recent developments. The paper closes with an outlook on future planned developments. 相似文献
108.
Thomas R. Bieler Bite Zhou Lauren Blair Amir Zamiri Payam Darbandi Farhang Pourboghrat Tae-Kyu Lee Kuo-Chuan Liu 《Journal of Electronic Materials》2012,41(2):283-301
Because failures in lead-free solder joints occur at locations other than the most highly shear-strained regions, reliability prediction is challenging. To gain physical understanding of this phenomenon, physically based understanding of how elastic and plastic deformation anisotropy affect microstructural evolution during thermomechanical cycling is necessary. Upon solidification, SAC305 (Sn-3.0Ag-0.5Cu) solder joints are usually single or tricrystals. The evolution of microstructures and properties is characterized statistically using optical and orientation imaging microscopy. In situ synchrotron x-ray measurements during thermal cycling are used to examine how crystal orientation and thermal cycling history change strain history. Extensive characterization of a low-stress plastic ball grid array (PBGA) package design at different stages of cycling history is compared with preliminary experiments using higher-stress package designs. With time and thermal history, microstructural evolution occurs mostly from continuous recrystallization and particle coarsening that is unique to each joint, because of the specific interaction between local thermal and displacement boundary conditions and the strong anisotropic elastic, plastic, expansion, and diffusional properties of Sn crystals. The rate of development of recrystallized microstructures is a strong function of strain and aging. Cracks form at recrystallized (random) boundaries, and then percolate through recrystallized regions. Complications arising from electromigration and corrosion are also considered. 相似文献
109.
Chang-Feng Wan Thomas Orent Thomas Myers Ishwara Bhat Andy Stoltz Joe Pellegrino 《Journal of Electronic Materials》2013,42(11):3359-3366
A new method for Cd-rich annealing of mercury cadmium telluride (MCT) was developed based on the observation that the deposition of Cd onto MCT by vacuum evaporation became self-limiting whenever the substrate temperature was above 70°C regardless of the Cd evaporation rate. Preliminary results indicated that this new method may be suitable for passivation of high-aspect-ratio MCT surfaces, for passivation at low temperatures, for in vacuo operation, and/or for vacancy annihilation in MCT. Furthermore, the process can be carried out in the conventional open-tube reactors used for molecular beam epitaxy, metalorganic chemical vapor deposition, and physical vapor deposition. 相似文献
110.
After the introduction of the basic concepts of Classical IP over ATM (CLIP), this paper presents an extension to this standard
as well as a full analysis of the technical viability of the extension proposal. One of the major drawbacks of CLIP is the
co-existence of IP and ATM without Quality of Service (QoS) support. By extending the functionality of CLIP and redefining
the mapping of IP and ATM addresses, QoS can be brought to IP-based applications without requiring any specific definition
or implementation changes at the IP layer or above. QACLIP (QoS for Applications using CLIP), the newly defined extension,
allows applications to request specific QoS for their data transfer use.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献