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321.
运用层序地层学的方法,利用地震岩性反演等手段,通过对东濮凹陷胡状集北部沙一段地层、构造、沉积等地质条件进行分析以及研究区油气分布规律的研究认为,胡状集北部沙一段各套地层的构造形态简单,构造圈闭少,对于寻找构造油气藏来说,勘探风险比较大。而研究区有多种典型的地震异常体,如盐类透镜体、上超、断续强反射等,这些地震异常体的发现对研究区寻找隐蔽油气圈闭有重要的指导意义。 相似文献
322.
With the development of system-on-chip (SoC) chips, more and more design houses are cooperating with each other's. How to achieve benefit sharing and key management for multiple intellectual properties (IPs) has become an emergency problem. This work proposes an orthogonal obfuscation method to protect multiple IPs. The proposed method permits cooperators to control the project using different security keys, protects the patterns with an orthogonal key, and be convenient for the user to manage the key. For reasons of increased security, the proposed method hides the original keys to prevent information leakage. Multi-port Physical Unclonable Function (MPUF) circuit is used as the additional orthogonal key to cluster membership. It protects the IPs from hardware attacks such as brute-force attack, member leakage attack, reverse engineering and so on. The security analyzes results show that the proposed method reduces the key retrieval time by 36.3% over the baseline. The proposed obfuscation methods have been successfully applied to ISCAS′89 benchmark circuits and cryptographic algorithms. Experimental results indicate that the orthogonal obfuscation only increases the area by 3.43% and consumes 2.77% more power than the baseline. 相似文献
323.
This paper presents the derivation, validates and illustrates the application of a Generalised Beam Theory (GBT) formulation developed to analyse the buckling behaviour of thin-walled members with arbitrarily ‘branched’ open cross-sections. Following a brief overview of the conventional GBT, one addresses in great detail the modifications that must be incorporated into its cross-section analysis procedure, in order to be able to handle the ‘branching’ points — they concern mostly issues related to (i) the choice of the appropriate ‘elementary warping functions’ and (ii) the determination of the ‘initial flexural shape functions’. The derived formulation is then employed to investigate the local-plate, distortional and global buckling behaviour of (i) simply supported and fixed asymmetric E-section columns and (ii) simply supported I-section beams with unequal stiffened flanges. For validation purposes, several GBT-based results are compared with ‘exact’ values, obtained by means of finite strip or shell finite element analyses. 相似文献
324.
阐述了塔式起重机附着装置的设计计算理论，建立了基于该理论的塔机附着装置计算机辅助设计系统。该系统能够快速准确地设计出符合实际情况的附着装置，同时自动完成施工图的绘制，并自动生成设计计算说明书和物料清单表，大大提高了工作效率。 相似文献
325.
汇编语言是面向计算机硬件的符号化的机器语言,通过学习汇编语言可以加深对计算机内部原理以及高级编程语言的理解。借助汇编语言低级化的特点,通过一个简单的C＋＋小程序和其对应的反汇编代码,从汇编语言的角度详细地分析和展示C＋＋中类和对象各成员在内存中的分布特点,从而帮助读者从本质上理解类、对象、成员变量和成员函数之间的各种关系。 相似文献
326.
采用多级模糊综合评价的理论与方法,建立路网服务水平的二级综合评价模型。通过模糊评价方法利用隶属度的概念定量地处理影响分析和评价的种种模糊因素,客观地描述了指标分级界限的模糊性,充分考虑了事物的中间过渡状态,为路网改造决策提供了更为全面的参考依据。 相似文献
327.
为实现白盒测试的源文件信息提取，提出了通过Lex和Yacc对使用上下文无关文法定义的语言进行词法和语法分析，构建独立的信息提取模块的思想。在函数信息提取部分提出了块和级的概念，用语句结构和语句链表结构将函数定义信息表示出来。在类信息提取部分通过识别出类声明中的成员变量和成员函数的声明信息，建立成员链表结构；识别类声明信息，建立类结构。然后将这些结构信息存入数据库，以供后续模块使用，充分做到了模块独立性和可重用性。这样只需要设计不同的信息提取模块，就可以将目前已经实现的面向C／C＋＋语言的软件测试工具WBoxTool推广应用到其它面向上下文无关文法的语言。 相似文献
328.
《Food Control》2017
Irradiation is an effective and safe method of food preservation, as it reduces spoilage, improves food hygiene, and extends shelf life. In October 2013, experts from Asia and Pacific Region gathered in Kuala Lumpur, Malaysia to share information on the application of food irradiation. The participants of the meeting discussed and analyzed the strengths and weaknesses of food irradiation with a view to sustainably continue the activity in the participating countries. The latest information in the Asia/Pacific Region regarding regulations, irradiation facilities and quantities irradiated is provided in this paper. The current status of food irradiation is reviewed and compared with the United States of America (USA) and European Union (EU). Activities on of food irradiation at commercial scale have increased significantly in these countries during last few years. Attention is also focused on the phytosanitary treatment of fruits and vegetables. Possible reasons for slow adoption of food irradiation and points to enhance the technology are also outlined. 相似文献
329.
330.
Lihong ZHOU;Changwei CHEN;Guomeng HAN;Fei YANG;Qianru SHI;Dongli FU;Yueqi DONG;Yue ZHAO;Lili SUN;Chen LIANG 《天然气工业》2021,41(05)
To further evaluate the shale gas enrichment conditions and exploration potentials of the continental lake basin in Qikou Sag of the Bohai Bay Basin,this paper studies the Es3(the third Member of Paleogene Shahejie Formation) shale in this area comprehensively from the aspects of sedimentary environment,lithology and its combination characteristics,hydrocarbon generation conditions,reservoir space,rock brittleness and gas bearing property by using seismic,wireline logging,mud logging and core analysis data. In addition,the shale gas accumulation pattern in this area is established and shale gas exploration potential is evaluated. And the following research results were obtained. First,the Es3 shale in this area is of great cumulative thickness and large distribution area,and in the middle-low slope area of Qikou Sag it has entered the stage of a large amount of gas generation,so it has the hydrocarbon generation conditions for scale shale gas reservoirs. Second,speaking of the shale in this area,the content of felsic minerals is dominant,and matrix pores and micro fractures are more developed to provide some reservoir spaces. Moreover,the content of brittle minerals is high,and the total con-tent of illite and illite/montmorillonite interlayer in clay minerals is 94%. The shale of low expansion and brittle can be fractured easily. Third,fluid expansion generated in the process of continuous hydrocarbon generation is the main cause of overpressure in Es3. The shale interval with pressure coefficient higher than 1.2 presents an obvious anomaly in while-drilling gas logging and has the conditions for shale gas accumulation. Fourth,when the burial depth of Es3in Qikou Sag is 3 100-4 400 m,shale gas and shale oil are associated mainly in the form of dissolved gas; when it is 4 400-4 850 m,wet gas is dominant; and when it is greater than 4 850 m,dry gas is dominant. In conclusion,the middle-low slope area in Qikou Sag is a favorable target area for shale gas exploration,whose favorable exploration area is about 1 476 km2 and shale gas resource is more than 1×1012 m3,indicating greater shale gas exploration potential. 相似文献