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131.
M Planas JR Masclans R Iglesia I Porta M Valls B Bermejo 《Canadian Metallurgical Quarterly》1997,13(3):202-205
Laparoscopic splenectomy has been accepted as a feasible extension of minimally invasive surgery, which has undergone dramatic improvements in both technology and instrumentation. We performed a laparoscopic splenectomy in a 7-year-old girl with hereditary spherocytosis. The patient recovered rapidly and returned to unrestricted activities quickly. The appropriate positioning of each laparoscopic port is essential for a good operative view and smooth access. It is also important to dissect the hilum of the spleen meticulously. Laparoscopic splenectomy in the pediatric age group appears to be another promising extension of laparoscopic surgery. 相似文献
132.
The study has tried to look at the political transition through the articles published by Spanish scientists in Spanish journals of Social Sciences and Humanities. A sample of 11000 article references from a selected set of 32 journals published from 1976 till 1985, has been the basis of the analysis. This time frame has been divided into two 5 year periods in order to detect any change in the topics published. The result of the analysis has been compared with the “events” as recorded by “El Pais” a very popular newspaper, during the same 10 year period and with a set of specific articles devoted to the Spanish political transition. 相似文献
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135.
Prediction of maximum recoverable mechanical energy via work integration: A thermodynamic modeling and analysis approach
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Thermal energy and mechanical energy are two common forms of energy consumed significantly in the process industries. While thermal energy can be effectively recovered using matured heat integration technologies, recovery of mechanical energy through work integration has not been fully explored. It is shown that work integration can be achieved through synthesizing work exchange networks (WENs), where work exchangers are operated in a batch mode, and compressors and expanders are operated in a continuous mode; this renders network synthesis a very sophisticated design task. It is greatly beneficial if the maximum amount of mechanical energy recoverable by a WEN can be determined prior to network design. In this article, we introduce a thermodynamic modeling and analysis method to identify accurately the maximum amount of recoverable mechanical energy of any process system of interest. The method is rigorous and general for target setting of mechanical energy recovery prior to WEN synthesis. © 2017 American Institute of Chemical Engineers AIChE J, 2017 相似文献
136.
Behzad Ghanavati Ebrahim Abiri Mohammad Reza Salehi Aida Keyhani Arindam Sanyal 《Analog Integrated Circuits and Signal Processing》2017,93(2):375-382
A highly energy efficient capacitor switching technique in a successive approximation register (SAR) analog to digital converter (ADC) for biomedical applications is presented. The proposed scheme based on new switching method, which combine the LSB split capacitive technique and monotonic method can reduce the average switching energy by 99.2% compared to the conventional SAR architecture. Besides reducing energy in each comparison cycle, the suggested method also achieves an 8× reduction in total capacitance used in the digital to analog converter over the conventional one with the same resolution. The proposed ADC can find application in biomedical engineering systems and other fields which low power consumption is needed. 相似文献
137.
Today, it is well known that taking into account the semantic information available for categorical variables sensibly improves the meaningfulness of the final results of any analysis. The paper presents a generalization of mixed Gibert’s metrics, which originally handled numerical and categorical variables, to include also semantic variables. Semantic variables are defined as categorical variables related to a reference ontology (ontologies are formal structures to model semantic relationships between the concepts of a certain domain). The superconcept-based distance (SCD) is introduced to compare semantic variables taking into account the information provided by the reference ontology. A benchmark shows the good performance of SCD with respect to other proposals, taken from the literature, to compare semantic features. Mixed Gibert’s metrics is generalized incorporating SCD. Finally, two real applications based on touristic data show the impact of the generalized Gibert’s metrics in clustering procedures and, in consequence, the impact of taking into account the reference ontology in clustering. The main conclusion is that the reference ontology, when available, can sensibly improve the meaningfulness of the final clusters. 相似文献
138.
The study aims at designing a set of indicators which, integrated altogether, should be albe to inform on the kind of research published in journal articles and its proximity to their specific forefornts. The set of indicators is composed of two subsets, one including information of the authors, research performers indicators, and other embodying information of the references used, source indicators. The source indicators are compared with the references pattern of specific paradigmatic journals used as standard framework of the research field. Three case studies dealing with the Spanish research on Immunology, Neurosciences and Pharmacognosy will be presented. The application of the indicators gave the following results: Spanish Immunology published in foreign journals was basic in its scope while the one published in domestric journals dealt with applied and clinical Medicine. Neuroscience publsiedh in foreign journals by financed Hospitals appertained to the forefront and presented a broad scope, Neuroscience Published in foreign journals by non-financed Hospitals was applied research and Neuroscience published by Universities, also in foreign journals, represented basic research done in a closed system. The case of Spanish Pharmacognosy is more difficult to interpret as three subject fields are involved (Pharmacology, Chemistry and Botany). The indicators did not clearly differentiate between the research published in domestic and foreign journals, although it seems that Spanish scientists are more interested in the pharmacological and botanical aspect of the natural products than in their chemical structure. 相似文献
139.
The estimation of semantic similarity between words is an important task in many language related applications. In the past, several approaches to assess similarity by evaluating the knowledge modelled in an ontology have been proposed. However, in many domains, knowledge is dispersed through several partial and/or overlapping ontologies. Because most previous works on semantic similarity only support a unique input ontology, we propose a method to enable similarity estimation across multiple ontologies. Our method identifies different cases according to which ontology/ies input terms belong. We propose several heuristics to deal with each case, aiming to solve missing values, when partial knowledge is available, and to capture the strongest semantic evidence that results in the most accurate similarity assessment, when dealing with overlapping knowledge. We evaluate and compare our method using several general purpose and biomedical benchmarks of word pairs whose similarity has been assessed by human experts, and several general purpose (WordNet) and biomedical ontologies (SNOMED CT and MeSH). Results show that our method is able to improve the accuracy of similarity estimation in comparison to single ontology approaches and against state of the art related works in multi-ontology similarity assessment. 相似文献
140.
Kazuyuki Tanaka Naoki Yamato Norikazu Kanao Shunsuke Aida 《Electrical Engineering in Japan》2019,206(2):16-24
In this paper, a touch fault calculation method is proposed based on the symmetric coordinate method. The touch fault in this paper means that a line‐to‐line short circuit fault occurred on parallel transmission lines stringing on a same tower. It is known that the touch fault occurs very rarely such as the galloping phenomena, and it causes an abnormal voltage rise especially on a low‐voltage transmission line. However, a quantitative analysis method of the abnormal voltage has not been proposed. Therefore, a general analysis method of the voltage profile solution for the touch fault is proposed based on the symmetrical coordinate method. The proposed method is able to calculate the precise voltage and current profile solution efficiently by introducing the similar formation for the touch fault solution same as the general fault solution. Demonstrative result to the application in the touch fault calculation is presented in order to verify the practicability of the proposed method. 相似文献