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31.
Successful operation of the Synchronous Overlap and Add (SOLA) algorithm for Time Scale Modification (TSM) of speech is closely tied to the proper choice of parameters. This paper investigates the quality of time scale modified speech under different values of primary parameters. Based on Mean Opinion Score (MOS) tests and Bark Spectral Distortion (BSD) measure, the proper choices of synthesis shift (Ss) and the duration of the shift search interval (K max?) are given experimentally. The conclusions can be helpful for operating the SOLA algorithm for time scale modification of speech. 相似文献
32.
33.
The requirements on an object-oriented DBMS for management of information in a large, complex enterprise are presented. These requirements aid in the achievement of an environment characterized by data sharing, open architectures, application and data portability, and assurance of data integrity. They were defined from the point of view of a user of the DBMS; therefore they describe the expected functionality of the DBMS and do not specify the method of implementation to achieve this functionality. They encompass requirements on the data model, query and data manipulation languages, the system architecure, interfaces to the system, change management, and transaction management. 相似文献
34.
Timothy Thomasma Kurt Hilbrecht 《International Journal of Flexible Manufacturing Systems》1991,3(3-4):231-250
Good methods are needed to specify, test, and debug material-handling control logic. This article surveys a number of representative methods for defining and describing control algorithms for programmable material-handling equipment used in flexible manufacturing systems. The methods are evaluated with regard to their suitability for communication between people and as bases for interfaces to automatic program generators. It is concluded that no single method is entirely satisfactory. Three methods (position diagrams, function block diagrams, and operation networks) have potential to be combined into an effective hybrid approach that minimizes the need for the user to switch between various conceptual models. 相似文献
35.
超低密度硬胶极压型油包水乳化钻井液在广安002-H9井的应用 总被引:2,自引:1,他引:1
在超低密度钻井液的使用方面,传统的油基钻井液和油包水钻井液存在易着火、安全性差的问题,而最近使用的美国3M公司的中空玻璃微珠聚磺钻井液又存在固控困难、钻井液费用很高等难题。为此,从选择合适的润湿反转剂和阻燃剂入手,在室内对获得的超低密度硬胶极压型油包水乳化钻井液成果配方进行了全面评价,并应用在广安002 H9井水平段欠平衡钻井中取得了良好效果。室内研究与现场应用表明,超低密度硬胶极压型油包水乳化钻井液能够很好地满足广安构造水平井段欠平衡钻井的需要。该钻井液体系具有防塌、润滑、携砂能力强,密度容易控制,钻井液单位成本合理并可重复使用,安全性好等显著特点,适合在类似广安构造的水平井段中推广应用。 相似文献
36.
37.
This paper examines Total Quality Management (TQM) as defined by Dr. W. Edwards Deming including Deming's fourteen points and explains how the United States' Department of Defense (DOD) defines TQM and why TQM is necessary. It also covers how the DOD is planning on implementing TQM and the policy that has been established as guidance in the implementation process. 相似文献
38.
A crack-tip screening analysis of cleavage fracture of steel is developed. The analysis incorporates evidence that reinitiation
of an arrested cleavage crack requires less stress intensity than cleavage initiation from a fatigue precrack. Fractographic
evidence as well as metallographic sectioning of arrested cracks have previously shown that the mechanism of rapid crack propagation
by cleavage is affected strongly by partial crack-plane deflection which leaves unbroken ligaments in its wake. The tearing
of these ligaments by dimple rupture is the dominant energy-absorbing mechanism. Earlier etch-pit experiments using an Fe-Si
alloy showed that the crack-tip stress intensity based on plastic zone size is extremely low. These observations are incorporated
into a model in which cleavage crack reinitiation is analyzed using a sharp crack that is shielded by a distribution of pinching
forces along its faces. During reloading of the arrested crack, the ligaments restrict crack-tip blunting, leading to higher
local stresses. As a result, lower stress intensities are needed for reinitiation than for initiation from a fatigue precrack. 相似文献
39.
Werner Baltes Gloria Bochmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(3):179-186
Summary From model roastings of mixtures containing serine, threonine and sucrose about 350 volatile compounds were separated and identified by GC/MS. Among them there were more than 100 monocyclic furans, 13 furanones and 8 bicyclic furans, the mass spectra and retention indices of which are recorded. The most important mass spectrometric fragmentation pathways are described. Spectra obtained from roasting coffee under identical conditions are compared with the spectra from model roastings.
Dissertation Gloria Bochmann, TU Berlin 1984 相似文献
Modell-Reaktionen zur Röstaroma-BildungII. Die massenspektrometrische Identifizierung von Furanen und Furanonen aus der Reaktion von Serin und Threonin mit Saccharose unter den Bedingungen der Kaffeeröstung
Zusammenfassung Aus Modellröstungen von Gemischen aus Serin, Threonin und Saccharose unter den Bedingungen der Kaffeeröstung wurden etwa 350 flüchtige Verbindungen mittels GC/MS getrennt und identifiziert. Unter ihnen befanden sich über 100 monocyclische Furane und 13 Furanone sowie 8 bicyclische Furane, deren Massenspektren und Retentions-indices angegeben werden. Die wichtigsten massenspektrometrischen Fragmentierungswege werden beschrieben. -Die aus einer gleich behandelten Röstung von Rohkaffee erhaltenen Spektren werden mit denen der Modellröstungen verglichen.
Dissertation Gloria Bochmann, TU Berlin 1984 相似文献
40.
We consider the switchbox routing problem of two-terminal nets in the case when all thek nets lie on two adjacent sides of the rectangle. Our routing model is the standard two-layer model. We develop an optimal algorithm that routes all the nets whenever a routing exists. The routing obtained uses the fewest possible number of vias. A more general version of this problem (adjacent staircase) is also optimally solved.This research was supported in part by NSA Contract No. MDA-904-85H-0015, NSF Grant No. DCR-86-00378, and by NSF Engineering Research Centers Program NSFD CDR 88003012. 相似文献