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781.
In wheat silage maintained for 21 days at 26°C and 9-9 kPa water vapour pressure under a continuous flow of modified atmospheres (MAs) containing 20% v/v O2 and different concentrations of CO2 (from 20 % v/v to 80 % v/v) there was a significant increase in pH and in the colony-forming units (CFU) of aerobic bacteria, yeasts and moulds. In addition, water-soluble carbohydrates (WSC) and acetic and lactic acids decreased considerably. Similar results were obtained with a continuous flow of 90 %, 95 % and 99 % v/v CO2 (supplemented to 100 % v/v with O2) and with 100 % v/v pure O2 Only with silage kept in an atmosphere of 100 % v/v CO2 or of 100 % v/v N2 were no changes observed.  相似文献   
782.
Bug Attacks     
In this paper we present a new kind of cryptanalytic attack which utilizes bugs in the hardware implementation of computer instructions. The best-known example of such a bug is the Intel division bug, which resulted in slightly inaccurate results for extremely rare inputs. Whereas in most applications such bugs can be viewed as a minor nuisance, we show that in the case of RSA (even when protected by OAEP), Pohlig–Hellman and ElGamal encryption such bugs can be a security disaster: decrypting ciphertexts on any computer which multiplies even one pair of numbers incorrectly can lead to full leakage of the secret key, sometimes with a single well-chosen ciphertext. As shown by recent revelation of top secret NSA documents by Edward Snowden, intentional hardware modifications is a method that was used by the USA to weaken the security of commercial equipment sent to targeted organizations.  相似文献   
783.
Interfacial fibrosis is known to dramatically decrease the lifespan, stability, and function of biomedical implants and bone-anchored prosthetics. Bioactive coatings aimed at mitigating fibrous adhesions are one of the approaches to alleviate the problem. In this paper, we are developing a bioactive coating based upon a magnetoelastic (ME) material that vibrates in response to an ac magnetic field. In order to establish these coatings for this purpose, the ME material was first rendered bioactive through the sequential addition of polyurethane and chitosan thin films. Indirect live/dead assays were performed showing increased cell viability for polyurethane and chitosan-coated sensors compared to the uncoated controls. Direct adhesion experiments were performed to test the response of fibroblasts cultured on static and vibrated ME materials. Results showed cells adherent to static but not vibrated coatings. Detached cells showed no viability loss compared to controls. The finding that submicrometer ME vibrations can prevent cell adhesion in vitro without inducing cell death suggests the potential of these coatings to effectively control interfacial fibrosis. Future work will address the effect of vibrations on cell morphology and local gene expression in vitro, as well as fibrous tissue formation in vivo.  相似文献   
784.
This paper presents an approach to detect epileptic seizure segments in the neonatal electroencephalogram (EEG) by characterizing the spectral features of the EEG waveform using a rule-based algorithm cascaded with a neural network. A rule-based algorithm screens out short segments of pseudosinusoidal EEG patterns as epileptic based on features in the power spectrum. The output of the rule-based algorithm is used to train and compare the performance of conventional feedforward neural networks and quantum neural networks. The results indicate that the trained neural networks, cascaded with the rule-based algorithm, improved the performance of the rule-based algorithm acting by itself. The evaluation of the proposed cascaded scheme for the detection of pseudosinusoidal seizure segments reveals its potential as a building block of the automated seizure detection system under development.  相似文献   
785.
This paper considers the usefulness of a production lot sizing and scheduling model at an animal nutrition plant with sequence-dependent setup times. The model covers multiple periods and is based on the asymmetric travelling salesman problem (atsp). It is applied initially to the case where the setup state is zeroed between periods, and then revised to model the carryover of the setup state from one period to the next. An iterative solution procedure based on subtour elimination is applied, and then enhanced by the inclusion of a subtour patching procedure. Case-based tests with actual plant data show that the subtour elimination is practicably fast where the setup state is zeroed between periods, but needs the patching procedure when the setup state is preserved, as is the situation at the plant. In this latter case, the subtour elimination and patching can be very fast, showing the method’s viability for operational lot sizing and sequencing in animal nutrition plants of the kind studied. Tests on perturbed plant data show that further algorithmic development is needed to tackle certain challenging variants found in other plants.  相似文献   
786.
Disk Paxos     
We present an algorithm, called Disk Paxos, for implementing a reliable distributed system with a network of processors and disks. Like the original Paxos algorithm, Disk Paxos maintains consistency in the presence of arbitrary non-Byzantine faults. Progress can be guaranteed as long as a majority of the disks are available, even if all processors but one have failed. Received: January 2001 / Accepted: March 2002  相似文献   
787.
We present optimization models and solution algorithms for the Vanpool Assignment Problem. A vanpool is typically a group of 9-15 passengers who share their commute to a common target location (typically an office building or corporate campus). Commuters in a vanpool drive from their homes to a park-and-ride location where they board a van and ride together to the target location; at the end of the work day they ride together back to the park-and-ride location. The Minimum Cost Vanpool Assignment Model (MCVAM) developed in this study is motivated by a program offered by Gulfstream Aerospace, a large employer in the Dallas/Fort-Worth area, Dallas Area Rapid Transit (DART), and Enterprise Rent-A-Car. Our MCVAM imposes constraints on the capacity of each van and quality-of-service constraints on the cost and travel time involved in joining a vanpool. The goal of the MCVAM is to minimize the total cost of a one-way trip to the target location for all employees (including those employees who opt-out of the program and choose not to join a vanpool). To the best of our knowledge, this is the first mathematical programming model proposed for the standard (one-stop) Vanpool Assignment Problem. The MCVAM models the current practice in vanpooling of using one park-and-ride location per vanpool. We also present a Two-Stop MCVAM (TSMCVAM) that offers significant cost savings compared to the MCVAM with little or no increase in trip times for most passengers by allowing vanpools to stop at a second park-and-ride location. We present heuristics for the TSMCVAM which are shown in a computational study to find solutions with optimality gaps ranging from 5% to 10% in CPU times ranging from 1 to 15 min for problem instances with up to 600 employees and 120 potential park-and-ride locations.  相似文献   
788.
This paper models a crisp Linear Programming (LP) as a Compromise Fuzzy Multi-Objective LP (CFMOLP). The application of CFMOLP has been focused on an industrial engineering problem that seeks profit maximisation by optimising product-mix. Imprecision of the large volume of industrial data and the conglomerated decision from all levels of management lead fuzzication of the identified constraints and the objective functions as well. The crisp model described is in the form of crisp-Multi-Objective Linear Programming (MOLP) with objective functions, functional constraints and non-negativity constraints. This model is formulated as a fuzzy-MOLP and subsequently converted into an equivalent compromise-MOLP model. The paper describes the development process for the CFMOLP model and its application along with appropriate interpretation.  相似文献   
789.
Five studies investigated the links among narcissism, self-esteem, and love. Across all studies, narcissism was associated primarily with a game-playing love style. This link was found in reports of general love styles (Study 1a) and of love in ongoing romantic relationships (Studies 1b-3, 5). Narcissists' game-playing love style was the result of a need for power and autonomy (Study 2) and was linked with greater relationship alternatives and lesser commitment (Study 3). Finally, narcissists' self-reports of game playing were confirmed by their partners in past and current relationships (Studies 4, 5). In contrast, self-esteem was negatively linked to manic love and positively linked to passionate love across studies. Implications for the understanding of narcissism in relationships are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
790.
Vector phase correlation   总被引:5,自引:0,他引:5  
Phase correlation has been applied for over 25 years to applications such as registration of images, but there has never been a simple generalisation to vector images. Here, for the first time, a vector approach to phase correlation, based on hypercomplex Fourier transforms, is proposed and demonstrated  相似文献   
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