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161.
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163.
Cheruppanpullil Radha Parigi Ramesh Kumar Vishweshwaraiah Prakash 《Journal of the science of food and agriculture》2008,88(2):336-343
BACKGROUND: There are a number of antinutritional factors present in soybeans that exert a negative impact on the nutritional quality of the protein. Among those factors that are destroyed by heat treatment are protease inhibitors and lectins. Protease inhibitors show antinutritional effect and moreover the digestibility of the protein is limited by the presence of these antinutrients. The aims of the present study are (1) to study the effect of autoclaving on the trypsin inhibitor inactivation, nitrogen solubility and protein digestibility of defatted soy flour and (2) to study the effect of enzymatic modification on the functional properties of autoclaved soy flour. RESULTS: The solubility of the soy flour decreased with increase in autoclaving time. Partial hydrolysis of the autoclaved soy flour increased its acid solubility (pH 4.5) from 17% to 56% over a control value of 24% without affecting its functional properties. Inactivation of trypsin inhibitors improved the protein digestibility of soy flour from 25% to 95%. Particle size analysis of the autoclaved flour indicated the formation of soy protein aggregates, which resulted in poor solubility. The enzymatic modification of autoclaved soy flour resulted in its property as a good emulsifying agent with an emulsion capacity of 118 ± 4 mL. CONCLUSION: Enzymatic modification of the heat‐processed soy flour increased its solubility and other functional attributes. The increased acid solubility would be advantageous in the utilization of soy proteins in acidic foods. Thus the autoclaved and partially modified soy flour is a potential source for specific functional foods. Copyright © 2007 Society of Chemical Industry 相似文献
164.
165.
Impact of S. aromaticum and C. cassia Incorporated Edible Films on Shelf Life of Seer Fish (Scomberomorus guttatus) Stored at Different Temperature Conditions
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166.
Detection of targets moving within a field of interest is a fundamental service Wireless Sensor Network (WSN) service. The
WSN’s target detection performance is directly related to the placement of the sensors within the field of interest. In this
paper, we address the problem of deterministic sensor deployment on the plane and in space, for the purpose of detecting mobile
targets. We map the target detection problem to a line-set intersection problem and derive analytic expressions for the probability
of detecting mobile targets. Compared to previous works, our mapping allows us to consider sensors with heterogeneous sensing
capabilities, thus analyzing sensor networks that employ multiple sensing modalities. We show that the complexity of evaluating
the target detection probability grows exponentially with the network size and, hence, derive appropriate lower and upper
bounds. We also show that maximizing the lower bound on the probability for target detection on the plane and in space, is
analogous to the problem of minimizing the average symbol error probability in two-dimensional and three-dimensional digital
modulation schemes, respectively, over additive white Gaussian noise. These problems can be addressed using the circle packing
problem for the plane, and the sphere packing problem for space. Using the analogy to digital modulation schemes, we derive
sensor constellations from well known signal constellations with low average symbol error probability.
相似文献
James A. RitceyEmail: |
167.
We investigate the problem of extending the network lifetime of a single broadcast session over wireless stationary ad hoc
networks where the hosts are not mobile. We define the network lifetime as the time from network initialization to the first
node failure due to battery depletion. We provide through graph theoretic approaches a polynomial-time globally optimal solution,
a variant of the minimum spanning tree (MST), to the problem of maximizing the static network lifetime. We make use of this
solution to develop a periodic tree update strategy for effective load balancing and show that a significant gain in network
lifetime over the optimal static network lifetime can be achieved. We provide extensive comparative simulation studies on
parameters such as update interval and control overhead and investigate their impact on the network lifetime. The simulation
results are also compared with an upper bound to the network lifetime.
A preliminary version of this paper appeared in IEEE ICC 2003 [35]. This research was funded in part by NSF grant ANI-0093187,
ONR award #: N00014-04-1-0479 and Collaborative Technology Alliance (CTA) from ARL under DAAD19-01-2-0011. All statements
and opinions are that of the authors and do not represent any position of the U.S government
Intae Kang received his B.S. degree in physics from Seoul National University, Seoul, Korea and M.S. degree in electrical engineering
from the Johns Hopkins University, Baltimore, MD. He is currently working toward the Ph.D. degree in the Department of Electrical
Engineering at the University of Washington, Seattle, WA.
His current research interests are in the area of ad hoc and sensor networks. In particular, he is interested in energy efficient
routing, topology control, medium access control, mobility management, and modeling and performance analysis of network protocols
using directional/smart antennas.
Radha Poovendran has been an assistant professor at the Electrical Engineering Department of the University of Washington at Seattle since
September 2000. He received his Ph.D. in Electrical Engineering from the University of Maryland, College Park in 1999. His
research interests are in the areas of applied cryptography for multiuser environment, wireless networking, and applications
of Information Theory to security. He is a recipient of Faculty Early Career Award from the National Science Foundation (2001),
Young Investigator Award from the Army Research Office (2002), Young Investigator Award from the Office of Naval Research
(2004), and the 2004 Presidential Early Career Award for Scientists and Engineers, for his research contributions in the areas
of wired and wireless multiuser security. He is also a co-recipient of the 2002 Outstanding Teaching as well as the Outstanding
Advisor Awards from the Department of Electrical Engineering of the University of Washington. 相似文献
168.
As group-oriented services become the focal point of ad hoc network applications, securing the group communications becomes
a default requirement. In this paper, we address the problem of group access in secure multicast communications for wireless
ad hoc networks. We argue that energy expenditure is a scarce resource for the energy-limited ad hoc network devices and introduce
a cross-layer approach for designing energy-efficient, balanced key distribution trees to perform key management. To conserve
energy, we incorporate the network topology (node location), the “power proximity” between network nodes and the path loss
characteristics of the medium in the key distribution tree design. We develop new algorithms for homogeneous as well as heterogeneous
environments and derive their computational complexity. We present simulation studies showing the improvements achieved for
three different but common environments of interest, thus illustrating the need for cross-layer design approaches for security
in wireless networks.
Loukas Lazos received the B.S. and M.S. degrees from the Electrical Engineering Department, National Technical University of Athens, Athens,
Greece, in 2000 and 2002, respectively. He is currently working towards the Ph.D. degree in the Electrical Engineering Department,
University of Washington, Seattle. His current research interests focus on cross-layer designs for energy-efficient key management
protocols for wireless ad-hoc networks, as well as secure localization systems for sensor networks.
Radha Poovendran received the Ph.D. degree in electrical engineering from the University of Maryland, College Park, in 1999. He has been an
Assistant Professor in the Electrical Engineering Department, University of Washington, Seattle, since September 2000. His
research interests are in the areas of applied cryptography for multiuser environment, wireless networking, and applications
of information theory to security. Dr. Poovendran is a recipient of the Faculty Early Career Award from the National Science
Foundation (2001), Young Investigator Award from the Army Research Office (2002), Young Investigator Award from the Office
of Naval Research (2004), and the 2005 Presidential Early Career Award for Scientists and Engineers, for his research contributions
in the areas of wired and wireless multiuser security. 相似文献
169.
Wireless ad hoc networks are envisioned to be randomly deployed in versatile and potentially hostile environments. Hence,
providing secure and uninterrupted communication between the un-tethered network nodes becomes a critical problem. In this
paper, we investigate the wormhole attack in wireless ad hoc networks, an attack that can disrupt vital network functions such as routing. In the wormhole attack,
the adversary establishes a low-latency unidirectional or bi-directional link, such as a wired or long-range wireless link,
between two points in the network that are not within communication range of each other. The attacker then records one or
more messages at one end of the link, tunnels them via the link to the other end, and replays them into the network in a timely
manner. The wormhole attack is easily implemented and particularly challenging to detect, since it does not require breach
of the authenticity and confidentiality of communication, or the compromise of any host. We present a graph theoretic framework
for modeling wormhole links and derive the necessary and sufficient conditions for detecting and defending against wormhole
attacks. Based on our framework, we show that any candidate solution preventing wormholes should construct a communication
graph that is a subgraph of the geometric graph defined by the radio range of the network nodes. Making use of our framework,
we propose a cryptographic mechanism based on local broadcast keys in order to prevent wormholes. Our solution does not need time synchronization or time measurement, requires only a small
fraction of the nodes to know their location, and is decentralized. Hence, it is suitable for networks with the most stringent
constraints such as sensor networks. Finally, we believe our work is the first to provide an analytical evaluation in terms
of probabilities of the extent to which a method prevents wormholes.
Radha Poovendran received the Ph.D. degree in electrical engineering from the University of Maryland, College Park, in 1999. He has been an
Assistant Professor in the Electrical Engineering Department, University of Washington, Seattle, since September 2000. His
research interests are in the areas of applied cryptography for multiuser environment, wireless networking, and applications
of information theory to security. Dr. Poovendran is a recipient of the Faculty Early Career Award from the National Science
Foundation (2001), Young Investigator Award from the Army Research Office (2002), Young Investigator Award from the Office
of Naval Research (2004), and the 2005 Presidential Early Career Award for Scientists and Engineers, for his research contributions
in the areas of wired and wireless multiuser security.
Loukas Lazos received the B.S. and M.S. degrees from the Electrical Engineering Department, National Technical University of Athens, Athens,
Greece, in 2000 and 2002, respectively. He is currently working towards the Ph.D. degree in the Electrical Engineering Department,
University of Washington, Seattle. His current research interests focus on cross-layer designs for energy-efficient key management
protocols for wireless ad-hoc networks, as well as secure localization systems for sensor networks. 相似文献
170.
The influence of neutral detergent fibre from Bengal gram on the utilisation of protein in albino rats was studied. Four market samples of Bengal gram and Bengal gram Annegeri variety harvested at three different stages of maturity were used for the study. The legumes were first analysed for proximate principles and then used as the source of nitrogen and fibre in the rat diets. Their proximate composition was similar to the values reported in literature. The content of neutral detergent fibre increased with increasing crude fibre. Growth of weanling rats was assessed on the basis of protein efficiency ratio (PER). Digestibility coefficient (DC), biological value (BV), total nitrogen retention (TNR) and net protein utilisation (NPU) were determined. PER, NPU, DC and nitrogen retention decreased with increase in fibre content in the diet. PER of Bengal gram sample with 14% neutral detergent fibre (NDF) was significantly different from the PER of all other samples. Biological value, however, was not affected by the fibre content. 相似文献