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91.
92.
Bibliometric analysis of tsunami research 总被引:3,自引:0,他引:3
The use of the bibilometric analytical technique for examining tsunami research does not exist in the literature. The objective
of the study was to perform a bibliometric analysis of all tsunami-related publications in the Science Citation Index (SCI).
Analyzed parameters included document type, language of publication, publication output, authorship, publication patterns,
distribution of subject category, distribution of author keywords, country of publication, most-frequently cited article,
and document distribution after the Indonesia tsunami. The US and Japan produced 53% of the total output where the seven major
industrial countries accounted for the majority of the total production. English was the dominant language, comprising 95%
of articles. A simulation model was applied to describe the relationship between the number of authors and the number of articles,
the number of journals and the number of articles, and the percentage of total articles and the number of times a certain
keyword was used. Moreover the tsunami publication patterns in the first 8 months after the Indonesia tsunami occurred on
26 December 2004 indicated a high percentage of non-article publications and more documents being published in journals with
higher impact factors. 相似文献
93.
In this paper, we propose an efficient design method for area optimization in a digital filter. The conventional methods to reduce the number of adders in a filter have the problem of a long critical path delay caused by the deep logic depth of the filter due to adder sharing. Furthermore, there is such a disadvantage that they use the transposed direct form (TDF) filter which needs more registers than those of the direct form (DF) filter. In this paper, we present a hybrid structure of a TDF and DF based on the flattened coefficients method so that it can reduce the number of flip‐flops and full‐adders without additional critical path delay. We also propose a resource sharing method and sharing‐pattern searching algorithm to reduce the number of adders without deepening the logic depth. Simulation results show that the proposed structure can save the number of adders and registers by 22 and 26%, respectively, compared to the best one used in the past. 相似文献
94.
A formal technique for incorporating two specification paradigms is presented,in which an algebraic specification is implemented by a set of abstract procedures specified in pre and post-condition style.The link between the two level specifications is provided via a translation from terms of algebraic specifications into temporal logic formulae representing abstract programs.In terms of translation,a criterion for an abstract implementation satisfying its specification is given,which allows one to check the consistency between the two levels of specifications.The abstract implementations can be refined into executable code by refining each abstract procedure in it.It is proved that the satisfication relation between a specification and its implementations is preserved by such refinement steps. 相似文献
95.
Tsung-Nan Kuo Yo-Shen Lin Chi-Hsueh Wang Chun Hsiung Chen 《Microwave and Wireless Components Letters, IEEE》2006,16(2):90-92
In this letter, a compact branch-line coupler is proposed by making good use of the three-dimensional layout capability of the low-temperature co-fired ceramic (LTCC) substrate. This branch-line coupler is accomplished by using lumped-inductors and lumped-capacitors to realize the modified-T equivalent-circuit model for the transmission line so that the circuit size may drastically be reduced. Specifically, a very compact LTCC branch-line coupler with a size of 0.079/spl lambda//spl times/0.0717/spl lambda/ is implemented and carefully examined, where /spl lambda/ is the wavelength of the multilayer structure at the operating frequency f/sub 0/. 相似文献
96.
Munhyoung Cho Chong Hyun Lee Soohong Kim Joohwan Chun 《AEUE-International Journal of Electronics and Communications》2004,58(4):299-301
In this paper, we propose a new robust code division multiple access (CDMA) receiver of which weight vector is obtained by projecting the effective spatio-temporal signature waveform onto the signal subspace of the data covariance matrix. We verified our proposed algorithm by the field measured data obtained with a custom-built wideband CDMA test-bed. It will be shown that the proposed algorithm is robust to the signal mismatch. 相似文献
97.
98.
在鱼罐喷粉预处理水模实验数据的基础上,进一步利用线性回归确定各工艺操作参数对喷吹基本参数(均混时间、粉剂穿透比和粉剂停留时间)的影响,得出各传输动力学基本参数的函数关系式。 相似文献
99.
A rotating disk air distribution (RDAD) system consisting of a rotating disk with an air supply hole was fabricated to solve the nonuniform freezing problem of a freezer that supplies air through a duct at a fixed location. The RDAD system was installed in a freezer to supply freezing air in various directions by controlling the position of the air supply hole. An equation estimating air velocity in the freezer was developed based on heat balance between a brass block thermocouple (BBT) probe and ambient air stream. The equation was applied to the analysis of airflow patterns developed through the RDAD and the fixed duct system. For control of the RDAD system, a fuzzy matrix was constructed with the measured nodal temperature at 3D locations in the freezer and used to search for the optimum direction of air supply. Uniform cooling was accomplished with the RDAD system using fuzzy and expert algorithms leading to temperature deviation σ=0.666, compared with 0.289 of the fixed air supply system. Cooling rate of model food (BBT) was 1.75 times faster than that of the fixed system. 相似文献
100.