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1.
Some substituted coumarins have been synthesized by von-Pechmann condensation using SnCl2 · 2H2O (10 mol %) as catalyst in ethanolic medium. The reactions are simple, easy in handling and environmentally benign. 相似文献
2.
Arjunan Arulchakkaravarthi Rakesh Kumar Parthasarathy Santhanaraghavan Sivaramakrishnan Muralithar Rengasamy Gopalakrishanan Perumalsamy Ramasamy 《Materials Research Innovations》2002,6(5-6):273-276
Organic molecular scintillating crystals are noted for their good timing and particle discrimination process. Trans-stilbene
is one such candidate noted for its good particle detection characteristics for the past five decades. Progressive strengthening
of detection characteristics of trans-stilbene has been attempted by improving crystal perfection. A series of timing resolution
studies have been carried out for the Bridgman grown trans-stilbene crystals under different experimental conditions. The
results were compared with the previously reported values. Pulse shape discrimination process has been carried out for 241Am and 252Cf sources and good discrimination has been obtained for gamma-alpha and gamma-neutron sources from the grown organic phosphor
crystal.
Electronic Publication 相似文献
3.
For complex reactions, the choice of reactor type is important for attaining optimum product yields. Strategies for specifying reactor types have beenIn this paper, product yield in a Van de Vusse reaction scheme has been studied for a wide range of the rate constants, in a reactor system consisting 相似文献
4.
Castor oil was hydrogenated to evaluate the effect of agitation during hydrogenation. The turbine and propeller impellers
were evaluated during hydrogenation of castor oil at various temperatures, pressures, and catalyst concentrations. The effect
of impeller position in the agitator at definite oil depth was also evaluated. Hydrogenation of castor oil at 130°C, 2.0 kg/cm2 hydrogen gas pressure with 0.5% Ni catalyst for 6 h while using two turbine impellers fitted in an agitator, one close to
the reactor bottom and another at a height just below the top oil layer, revolving at 350 rpm, resulted in a product of a
iodine value of 4.1, hydroxyl value of 156.4, and slip point of 84°C. 相似文献
5.
Differencing and merging of architectural views 总被引:1,自引:0,他引:1
Marwan Abi-Antoun Jonathan Aldrich Nagi Nahas Bradley Schmerl David Garlan 《Automated Software Engineering》2008,15(1):35-74
Differencing and merging architectural views is an important activity in software engineering. However, existing approaches
are still based on restrictive assumptions, such as requiring view elements to have unique identifiers or exactly matching
types, which is often not the case in many application domains.
We propose an approach based on structural information. We generalize a published polynomial-time tree-to-tree correction
algorithm that detects inserts, renames and deletes, into a novel algorithm that additionally detects restricted moves. Our
algorithm also supports forcing and preventing matches between view elements.
We incorporate the algorithm into tools to compare and merge Component-and-Connector (C&C) architectural views. We provide
an empirical evaluation of the algorithm. We illustrate the tools using extended examples, and use them to detect and reconcile
interesting differences between real architectural views.
This article is an expanded version of the following paper: Abi-Antoun, M., Aldrich, J., Nahas, N., Schmerl, B., and Garlan, D:
2006, ‘Differencing and Merging of Architectural Views’. In: Proceedings of the 21st IEEE International Conference on Automated Software Engineering, pp. 47–58. 相似文献
6.
Yadav Vijay Kumar Yadav Rakesh Kumar Verma Shekhar Venkatesan S. 《The Journal of supercomputing》2022,78(2):2386-2416
The Journal of Supercomputing - In the Attribute-Based Encryption (ABE) scheme, patients encrypt their electronic health record (EHR), attach the appropriate attributes with it, and outsource them... 相似文献
7.
This paper presents a practical heap analysis technique, connection analysis, that can be used to disambiguate heap accesses in C programs. The technique is designed for analyzing programs that allocate many disjoint objects in the heap such as dynamically-allocated arrays in scientific programs. The method statically estimates connection matrices which encode the connection relationships between all heap-directed pointers at each program point. The results of the analysis can be used by parallelizing compilers to determine when two heap-allocated objects are guaranteed to be disjoint, and thus can be used to improve array dependence and interference analysis. The method has been implemented as a context-sensitive interprocedural analysis in the McCAT optimizing/parallelizing C compiler. Experimental results are given to compare the accuracy of connection analysis versus a conservative estimate based on points-to analysis. 相似文献
8.
Ohad Gur Manav Bhatia William H. Mason Joseph A. Schetz Rakesh K. Kapania Taewoo Nam 《Structural and Multidisciplinary Optimization》2011,44(2):277-298
The paper describes the development of a multidisciplinary design optimization framework for conceptual design of truss-braced
wing configurations. This unconventional configuration requires specialized analysis tools supported by a modular and flexible
framework to accommodate different configurations. While the previous framework developed at Virginia Tech was a monolithic
Fortran-77 code, the need for more flexibility for complex truss-braced wing configurations was addressed by the development
of this new framework, which is based on Phoenix Integration ModelCenterTM environment. The framework uses updated structural and aerodynamic design modules that enable a more general geometry definition.
The new framework, thus, provides a foundation for future design concepts, especially multi-member truss-braced wing configurations.
The fuel saving potential of these truss-braced wing configurations is presented by comparing different truss designs with
gradually increased level of complexity. 相似文献
9.
Radio Frequency Identification (RFID) based systems have been used in different applications in the Architecture, Engineering, Construction, Owner and Operator (AECOO) industry. Applications are mainly designed for specific lifecycle stage of the facility and serve the needs of only one of the stakeholders. This would increase the cost and the labor for adding and removing tags and eliminate the chance of using shared resources. In this paper, the usage of tags permanently attached to components is proposed where the memory of the tags is used during the lifecycle by different stakeholders for data storage and handover. A Building Information Model (BIM) database is used for tackling the interoperability issues allowing different users to access and share the data. To securely and efficiently store data on RFID tags in ifcXML format, multi-level encryption together with role-based access control is applied on the data stored on RFID tags. Each user is assigned a certain role and can only access the part of data for which he has authorization according to a predefined role and the Access Control Policy. To explore the technical feasibility of the proposed approach, a case study considering both facilities management and emergency management has been implemented and tested at Concordia University. 相似文献
10.
Kaushik Bhattacharyya Rakesh Biswas Anindya Sundar Dhar Swapna Banerjee 《Microprocessors and Microsystems》2010,34(2-4):96-101
A new scaled radix-4 CORDIC architecture that incorporates pipelining and parallelism is presented. The latency of the architecture is n/2 clock cycles and throughput rate is one valid result per n/2 clocks for n bit precision. A 16 bit radix-4 CORDIC architecture is implemented on the available FPGA platform. The corresponding latency of the architecture is eight clock cycles and throughput rate is one valid result per eight clock cycles. The entire scaled architecture operates at 56.96 MHz of clock rate with a power consumption of 380 mW. The speed can be enhanced with the upgraded version of FPGA device. A speed-area optimized processor is obtained through this architecture and is suitable for real time applications. 相似文献