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421.
FA composition of crude oil recovered from catfish viscera 总被引:3,自引:3,他引:0
Subramaniam Sathivel Witoon Prinyawiwatkul Casey C. Grimm Joan M. King Steven Lloyd 《Journal of the American Oil Chemists' Society》2002,79(10):989-992
The FA composition of crude catfish oil recovered from whole viscera, digestive tract, liver, gallbladder, and visceral storage
fat was determined and compared with that of fillet and nugget (abdominal portion). About 34% crude fat (wet basis) could
be recovered from the whole catfish viscera. FA found in crude catfish visceral oil were C14∶0, C16∶0, C16∶1, C18∶0, C18∶1,
C18∶2, C18∶3, C20∶0, C20∶1, C20∶2, C20∶3, C20∶4, and C22∶6, the predominant FA being C18∶1, C16∶0, C18∶2, and C18∶0. Catfish
visceral oil was characterized by a high level of unsaturated FA, which was similarly found in fillet and nugget. Total unsaturated
FA in visceral oil amounted to 261.3 mg/g (dry basis) compared to that of fillet (259.3 mg/g) and nugget, (307.6 mg/g). The
whole viscera contained 4.2 mg/g DHA compared to that of gallbladder (9.2 mg/g), fillet (9.3 mg/g), and nugget, (10.7 mg/g).
The total n−3 FA in the whole and/or portioned visceral ranged from 4.3 to 20.9 mg/g. 相似文献
422.
The fluid-flow pattern and residence-time distribution (r.t.d.) of the fluid in a continuous casting mould have been studied using a water model. The two recirculating zones below the discharge ports have been found to be asymmetric. The effect of casting speed, discharge port diameter, shroud well depth and the immersion depth on r.t.d. have been investigated. The r.t.d. curve has been well represented by a model of two backmix cells of equal volume in series. The exit of the fluid has been found to be non-uniform across the cross-section of the mould. The fluid-flow pattern has been observed to change with time in a random fashion. Dead volume of upto 31.8% has been found with smaller discharge ports. 相似文献
423.
424.
C. Meid U. Waedt A. Subramaniam J. Wischek M. Bartsch P. Terberger R. Vaßen 《Materialwissenschaft und Werkstofftechnik》2019,50(7):777-787
A newly developed miniature specimen and respective fixture for high temperature low cycle fatigue testing of nickel based single crystal superalloys is presented. Miniaturization allows the preparation of test specimens in all main crystallographic orientations of the cubic nickel crystal using laboratory sized material samples and enables excellent utilization of the costly material. The specimen geometry is optimized by means of parameter studies employing numerical calculations such that for the main crystallographic orientations the stress concentration at the fillet between gauge length and specimen head is minimized, and failure is likely to occur within the gauge length. The designed fixture allows easy specimen mounting and provides sufficient support for applying an extensometer for strain measurement. Protective metallic coatings against oxidation can be applied on the specimen by plasma spraying for studying the effect of coatings on the fatigue lifetime. The functionality of the specimen geometry and fixture design for low cycle fatigue testing is demonstrated for temperatures up to 950 °C. 相似文献
425.
Mojtaba Seyedzadegan Mohamed Othman Borhanuddin Mohd Ali Shamala Subramaniam 《Journal of Network and Computer Applications》2013,36(6):1705-1723
Internet GateWays (IGWs) are responsible for connecting the backbone wireless mesh networks (BWMNs) to the Internet/wired backbone. An IGW has more capabilities than a simple wireless mesh router (WMR) but is more expensive. Strategically placing the IGWs in a BWMN is critical to the Wireless Mesh Network (WMN) architecture. In order to solve the problem of IGWs placement in BWMNs, a novel algorithm is proposed in this paper. The new algorithm is involved in placing a minimum number of IGWs so that the Quality of Service (QoS) requirements are satisfied. Different from existing algorithms, this new algorithm incrementally identifies IGWs and prioritively assigns wireless mesh routers (WMRs) based on the computed degree of WMRs to identified IGWs. Performance evaluation results show that proposed algorithm outperforms other alternative algorithms by comparing the number of gateways placed in different scenarios. Furthermore, having control of the distribution of IGWs in order to locate them closest to available Internet/wired network connection points is an added advantage of this algorithm. 相似文献
426.
Chandrasekar Subramaniam Michael J. Shaw David M. Gardner 《Information Systems Frontiers》2000,1(4):363-378
Marketing managers developing strategies to market products on the Internet are faced with important issues. We suggest that the use of Web advertising, virtual store-fronts and virtual communities provides innovative opportunities for marketers to communicate with consumers, understand their preferences and personalize the marketing offers at far lesser costs and far more effectively than through traditional means. The Web can also extend to fulfill the transaction and distribution needs of the consumers through new consumer processes, and thus becomes a new marketing channel. Considering the unique characteristics of the Web and traditional channels, we suggest the use of product and market characteristics in identifying the right channel for the right product. Further, we present a new framework of channel management strategies to help organizations effectively integrate the Web channel into their marketing strategy. 相似文献
427.
Specification-based Testing for Gui-based Applications 总被引:1,自引:0,他引:1
The development of GUI-based applications has raised a lot of new issues, one of them being how to automate effective testing for applications with complicated graphical user interactions. In this paper, we discuss the architectural issues and the implementation concerns of our approach to an automated specification-based testing technique for GUI-based applications. This approach is carried out by enriching existing architecture for automated specification-based testing. An essential part of our work is a visual environment to obtain test specifications. This environment pre-runs the Application Under Test (AUT) under its own control, with two prominent characteristics: First, testers can edit test specifications within the true GUI environment of the AUT. Second, the recorded input and output contain the same references as those in the AUT, so that the test cases generated from the edited specification can be used directly by test oracles during the automated testing procedure.We present our running prototype of a visual specification editor that allows users to graphically manipulate test specifications when these specifications are given in term of Finite State Machines (FSM) and the implementations of the AUT are GUI-based Java applications. 相似文献
428.
In this paper, an alternative method for solving optimal control problems is presented. By applying calculus of variations, the optimal control problem can be reduced to solving a two-point boundary value problem. Here, the solution is generated with a combination of two methods genetic algorithms (GA) and the shooting method. An estimate of the optimal solution is first obtained using GA. This solution is in turn used as the initial guess for the shooting method. This combined method is applied to an optimal missile guidance problem. The performances of the combined method and GA are evaluated by simulation and compared. The results clearly show that the proposed combined method is able to locate the optimal solution more efficiently than GA. The results also show that the combined method never fails to correctly determine the optimal solution. Therefore, it proves to be more robust than the shooting method whose convergence is not always guaranteed. 相似文献
429.
430.
Hopman W.C.L. van der Werf K.O. Hollink A.J.F. Bogaerts W. Subramaniam V. de Ridder R.M. 《Photonics Technology Letters, IEEE》2008,20(1):57-59
We present a transmission model for estimating the effect of the atomic-force microscopy tapping tip height on a photonic crystal microcavity (MC). This model uses a fit of the measured tip-height-dependent transmission above a ldquohot spotrdquo in the MC. The predicted transmission versus average tapping height is in good agreement with the values obtained from tapping mode experiments. Furthermore, we show that for the existing, nonoptimized structure, the transmission coefficient can be tuned between 0.32 and 0.8 by varying the average tapping height from 26 to 265 nm. A transmission larger than that of the undisturbed cavity at resonance was observed at specific tip locations just outside the cavity-terminating holes. 相似文献