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841.
This paper deals with the experimental aspects of ultrasonic delay lines in liquid media and is a sequel to a previous paper treating the general theory of such devices.Delay devices employing ultrasonic propagation through liquids have proved satisfactory for delay times of the order of 3 milliseconds or less. Such devices can be made broadband and give excellent reproduction of pulse shape. The design considerations for such devices are discussed and illustrated by actual examples. 相似文献
842.
In this paper, an algorithm is developed to apply Hann, Hamming, Blackman and related windows directly in the transform domain for the discrete cosine transform and discrete sine transform. These algorithms are useful in applications where windowing is required in order to minimize edge effects caused by implicit symmetries in the transform domain that are not replicated in the real-world data. Examples of such applications include data communication, adaptive system identification and filtering, real-time analysis of financial market data, etc. Software implementations in C language are also given. 相似文献
843.
M. V. R. Reddy R. Alli B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2000,15(1):127-135
Lymphatic filariasis caused mainly by infection fromWuchereria bancrofti andBrugia malayi remains as the major cause of clinical morbidity in tropical and subtropical countries. Development of vaccine against filarial infection can act as additional measure to the existing therapeutic and vector control methods in the control of this disease. The main hurdles in the development of anti-filarial vaccine are the strict primate specificity ofWuchereria bancrofti, the paucity of parasite material, the diversity of clinical manifestations and their associated complex immune responses, lack of clear understanding on host-parasite interactions and the mechanisms involved in protective immunity. However in the past few years, the information generated in immuno-epidemiological studies, correlated with observations in experimental animals suggests that a filarial vaccine is feasible. Initially live irradiated infective larvae have been successfully used to induce high level of protective immunity in several animal models. Applying diverse strategies, variety of purified or recombinant filarial antigens have been explored for their ability to induce protection in different host-parasite systems. Some of these targeted filarial antigens induced high level of resistance in experimental animals against challenge infections. More focussed studies on thorough characterization of parasitological and immunological changes associated with resistance induced by such candidate protective antigens and on delivery mechanisms and safety aspects will be crucial in their selection for possible use in humans. 相似文献
844.
845.
846.
R. Kumar S. B. Pachori G. K. Senger Satyanand L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1994,9(2):72-74
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial
effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown
a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was
observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic
arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis
specially tubercular in initial stages. 相似文献
847.
848.
The commodification of code demands two preconditions: a belief if the existence of code and a system of ownership for the code. An examination of these preconditions is helpful for resisting the further widening of digital divides. The ontological belief in the relatively independent existence of code is dependent on our understanding of what the “digital” is. Here it is claimed that the digital is not a natural kind, but a concept that is relative to our practices of interpretation. An interpretative system that sees code as something that can or should always be owned implies an increase of social control and threatens vital processes of knowledge creation that are necessary for an open and egalitarian information society. The ontological belief in “digital code” thus provides the backdrop for an ethical view of the information society. Consequently, if we see digital code as an interpretative notion (in the nominalist way), the ethical questions appear in a different light. 相似文献
849.
For some 300 years the modelling of uncertainty in the sciences has been totally dominated by probabilistic methods. Now, following major criticism of the theoretical foundations of probability theory, other approaches to dealing with uncertainty are being explored. 相似文献
850.
Patrocinio Zaragoza-Sáez Enrique Claver-Cortés Bartolomé Marco-Lajara Mercedes Úbeda-García 《知识管理研究与实践》2016,14(4):489-501
Knowledge creation is one of the most important dynamic capabilities that firms can use to develop new assets, which can represent the basis for future innovations. Within a context of growing globalisation, the acquisition and creation of knowledge is one of the main objectives sought with international expansion. The consideration of intellectual capital within the knowledge creation process in subsidiaries offers an innovative way to undertake knowledge management practices in multinationals. Theoretical and empirical works can be found in the literature about intellectual capital. However, very few studies link intellectual capital to knowledge creation in multinationals. Seeking to fill this gap, the purpose of this paper is to develop and test a model that includes the main intangibles belonging to structural and relational capital that can influence knowledge creation in Spanish subsidiaries of foreign multinational firms belonging to high-technology and knowledge-intensive sectors. Theoretical, empirical and managerial contributions result from this paper. 相似文献