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961.
Parallel programs are intrinsically non-deterministic, and therefore the techniques of cyclical debugging that are commonly used for sequential programs are not suitable for parallel ones. This paper proposes a method to reproduce Occam program behaviour. Saving information on the timer values input by the program and the guards selected at run-time on alternative commands allows program replay, i.e. it makes it possible to re-execute the program deterministically with the same inputs following the same instruction path. This enables the software developer to use tools such as debuggers and intrusive monitors to help identify program faults. After discussing possible implementations of the proposed technique, IRD (an interactive replay debugger for Occam programs) is described. Finally, the use of the IRD in a sample debug session is presented as an example.  相似文献   
962.
为了研究养心菜的加工适用性,拓展其利用途径,采用未预处理(Untreated,UT)、沸水漂烫(Boiling Water Blanching,BWB)、沸水+护色漂烫(COLOR Protection+Water Blanching,CPB)、蒸汽漂烫(Steam Blanching,SB)与冻融(Freeze-Thawing,FT)五种预处理方式处理后,分别进行热风干燥(Hot Air Drying,HA)、热泵干燥(Heat Pump Drying,HP),得到UT HP、UT HA、BWB HP、BWB HA、CPB HP、CPB HA、SB HP、SB HA、FT HP及FT HA 10种养心菜粉,比较不同预处理方式和干燥方式下养心菜色泽、功能成分及抗氧化能力水平的变化。结果表明:UT HP没食子酸和山萘酚含量最高,但色泽差、叶绿素含量较低,干燥时间长;CPB HP的干燥时间短,Vc含量最高,具有较高的抗氧化水平,但没食子酸含量较低;SB HP总酚、总黄酮、槲皮素含量最高,其他品质指标介于中间;FT HP养心菜具有最好的色泽、最高的叶绿素、游离氨基酸含量,但总酚、总黄酮、槲皮素、山萘酚以及抗氧化水平低。从主成分分析来看,BWB HP、CPB HP、SB HP 和BWB HA、CPB HA、SB HA的养心菜品质分别具有一定的相似性,UT HP、FT HP、UT HA、UT HA和其有明显差异。该文综合比较了养心菜不同预处理及干燥方法的优劣,在养心菜下游的功能性食品的开发过程中,可以根据需求选择合适的干燥方法。  相似文献   
963.
The retinal pigmented epithelium (RPE) plays a pivotal role in retinal homeostasis. It is therefore an interesting target to fill the unmet medical need of different retinal diseases, including age-related macular degeneration and Stargardt disease. RPE replacement therapy may use different cellular sources: induced pluripotent stem cells or embryonic stem cells. Cells can be transferred as suspension on a patch with different surgical approaches. Results are promising although based on very limited samples. In this review, we summarize the current progress of RPE replacement and provide a comparative assessment of different published approaches which may become standard of care in the future.  相似文献   
964.
本文针对中国石油哈尔滨石化公司三催化装置CO余热锅炉存在的各换热面积灰严重的问题,介绍了脉冲吹灰装置应用后的实际效果,并对吹灰器使用过程中存在的部分问题提出了建议。  相似文献   
965.
We present the results of SHORTEST, a BRITE EURAM II project for the introduction in industry of an advanced approach to the reliability evaluation of electronic assemblies. The achievements so far are the development and validation of seven in-situ test techniques. Five of the test techniques demonstrate the capability of detecting failure mechanisms at 48 hours with moderate stress conditions, and half of the in-situ test results obtained at 48 hours on 10 subtechnologies correlate with conventional tests. All correlation results are presented. The application of the method for quality assurance and building-in reliability is discussed. The final aim of SHORTEST is to look for the exploitation of the developed in-situ techniques. The marketing study that will define the industrial needs of European companies is presented. In parallel, the insertion in the CECC specification of recommendations based on the SHORTEST principle is foreseen.  相似文献   
966.
耿玉亮  须德 《电子学报》2006,34(7):1342-1346
摄像机运动分类是基于内容的视频分析和理解的重要问题.本文通过对运动矢量场的分析,提出了一种基于统计学习的、分层次的摄像机运动分类算法.该算法利用支持向量机(SVM)在有限样本条件下的学习能力,实现摄像机运动类型的初步分类;然后,充分考虑运动矢量场的方向和位置信息,进一步区分缩放和旋转操作,并识别摄像机平移操作的方向.算法在运动矢量的预处理过程中引入摄影规则,有效地降低了前景运动噪声的影响.  相似文献   
967.
968.
This paper describes the preparation and properties of in-situ composites based on polymers with no overlap in processing temperatures. The polymers used were Vectra A900, a thermotropic liquid crystalline copolyester (TLCP), and Arnitel em630, a thermoplastic elastomer. Blends were generated by feeding the two components from separate extruders into a Ross static mixer. Different morphologies were obtained by varying the number of mixing elements of the static mixer. Using 8 mixing elements led to a stratified morphology of Vectra layers in Arnitel, using 11 mixing elements resulted in the desired continuous fiber/matrix morphology whereas a pronounced skin-core morphology was obtained with 14 mixing elements. It is argued that in-situ composites can be generated by a distributive mixing process without the formation of an intermediate droplet/matrix morphology as occurs in common dispersive blending equipment. Tensile modulus and strength of all blends increased with extrudate draw ratio as a result of increased molecular orientation of the TLCP phase. The level of reinforcement, however, was lower than expected, probably due to the low temperature of drawing. Annealing and capillary instability experiments showed that above the melting point of the TLCP the fiber/matrix morphology rapidly breaks up into a droplet/matrix morphology. This process takes just a few seconds for fibers of thickness ∼ 1 μm. It is shown to be the probable cause of the skin-core morphology obtained in case of 14 mixing elements.  相似文献   
969.
基于原始套接字的网络安全研究与实现   总被引:1,自引:0,他引:1  
围绕信息的获取、使用和控制的竞争愈演愈烈,网络安全问题变得日益重要,信息安全成为维护国家安全和社会稳定的一个焦点。如何辨别防御与攻击和增强网络安全已成为网络运营商和技术管理人员、甚至普通网络用户研究的问题。在网络安全方面,利用原始套接字实现网络嗅探可以有效地探测在网络上传输的数据包信息,对这些信息的分析有助于网络安全的维护.  相似文献   
970.
Diamond-Blackfan anaemia (DBA) is a red blood cell aplasia that in the majority of cases is associated with ribosomal protein (RP) aberrations. However, the mechanism by which this disorder leads to such a specific phenotype remains unclear. Even more elusive is the reason why non-specific agents such as glucocorticosteroids (GCs), also known as glucocorticoids, are an effective therapy for DBA. In this review, we (1) explore why GCs are successful in DBA treatment, (2) discuss the effect of GCs on erythropoiesis, and (3) summarise the GC impact on crucial pathways deregulated in DBA. Furthermore, we show that GCs do not regulate DBA erythropoiesis via a single mechanism but more likely via several interdependent pathways.  相似文献   
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