一种层号识别系统在生瓷叠片机上的应用

叠片机是LTCC多层基板制造生产线中关键的设备,在叠层过程中及时记录各层编号,对预防错层叠压,以及发生撕膜损坏或对位失败时进行产品更换有着重要作用。将层号识别系统安装在产品预定位台上,每次来料先通过图像拍照进行层号识别,记录每层的基本信息,提高了生瓷叠片机设备自动化水平,对多层叠层工艺的良品率提升,以及微组装技术成本的降低带来了新的解决办法。

轮胎X射线0号带束层接头检测定位量化算法的研究

轮胎成型过程中受设备及生产工艺等因素影响,因搭接量不同会造成0号带束层接头缺陷。根据轮胎X射线图像的纹理分布特点,以及缺陷区域的灰度分布特征,提出了轮胎X射线0号带束层接头检测定位量化算法。MATLAB的仿真分析表明,该算法能够准确对0号带束层接头缺陷进行定位,并量化接头大小,其误判率为3.4%,漏判率为2%。该算法克服了人工评定的不足,使评判过程更加科学化、客观化、规范化,缺陷检测结果满足工业要求,为后续的产品分级提供了技术及数据支持。

八面台油田北部青一段20号小层油藏成藏主控因素分析

通过对八面台油田北部青一段20号小层油藏分析,对其成藏条件及主控因素的由弱到强分为四个层级:一级为烃源岩油源供给充足。源于中央坳陷区广泛分布的青一段湖相泥岩生成的轻质原油向西高部位侧向运移进入青一段储层聚集成藏;二级为断层的控制作用。近南北向断层与渗透性砂体构成断层-岩性圈闭。断层控制了区域上原油分布范围,但对局部原油富集控制作用有限;三级为构造高点。从构造精细解释成果来看,单一因素的构造圈闭,分布面积十分有限,构造高点对油藏富集的控制作用不明显;四级为沉积微相砂体。本区对原油富集最有利的沉积微相为三角洲前缘河口沙坝、其次为水下分流河道砂体。

杏花矿36号层在西一采区储量分布赋存状态及煤层的可采性分析

杏花矿36号层在西一采区储量分布和赋存状态及煤层的可采性分析

柴达木盆地北缘下构造层岩性特征及其构造演化

根据地表地质特征及钻井资料,分析了冷湖三号油田下构造层岩性特征,认为冷湖三号油田下构造层只有下侏罗统。下侏罗统由下而上包括湖西山组(分为暗绿色段和含炭段)和小煤沟组,含油层段赋存于小煤沟组。根据连井剖面和地震剖面,油区现今为一单斜构造,可划分为三个断块区。推测该构造区经历了从侏罗纪以来的早侏罗纪断陷沉积、晚侏罗纪隆升剥蚀、古近纪再次沉积、第三纪末再次剥蚀等四个阶段。

泌阳凹陷深凹区页岩非均质性与含油性特征分析

页岩的非均质性和含油性研究,对揭示页岩油微观富集规律和页岩油开发都具有重要意义。运用地球化学、核磁共振、岩心观察、X衍射等方法,对南襄盆地泌阳凹陷页岩岩性、矿物组成、有机质丰度、孔渗性和含油性等特征进行了研究。结果表明:泌页1井5号页岩层有机质丰度呈中部高、顶底低的分布特点;中部和底部页岩段的含油量比顶部高;顶部页岩段粉砂质质量分数较高,中部页岩段灰质质量分数较高,底部页岩段云质质量分数较高;页岩中陆源碎屑矿物质量分数随深度增加而增多,黏土矿物质量分数则相反,碳酸盐矿物质量分数呈中部高、顶底低的趋势;页岩渗透率随深度增加而增大,而孔隙度变化不大;页岩层形成于干旱气候下具有中—高等生产力的咸水还原环境中;有机质丰度、脆性矿物质量分数、孔隙度和烃类微运移作用是影响页岩含油量的主要因素;与高有机质丰度页岩层段相邻的泥质粉砂岩和云质页岩夹层是页岩油开采的有利层段。

Reservoir information extraction using a fractional Fourier transform and a smooth pseudo Wigner-Ville distribution

Currently, it is difficult for people to express signal information simultaneously in the time and frequency domains when analyzing acoustic logging signals using a simple-time or frequency-domain method. It is difficult to use a single type of time-frequency analysis method, which affects the feasibility of acoustic logging signal analysis. In order to solve these problems, in this paper, a fractional Fourier transform and smooth pseudo Wigner Ville distribution （SPWD） were combined and used to analyze array acoustic logging signals. The time-frequency distribution of signals with the variation of orders of fractional Fourier transform was obtained, and the characteristics of the time-frequency distribution of different reservoirs under different orders were summarized. Because of the rotational characteristics of the fractional Fourier transform, the rotation speed of the cross terms was faster than those of primary waves, shear waves, Stoneley waves, and pseudo Rayleigh waves. By choosing different orders for different reservoirs according to the actual circumstances, the cross terms were separated from the four kinds of waves. In this manner, we could extract reservoir information by studying the characteristics of partial waves. Actual logging data showed that the method outlined in this paper greatly weakened cross-term interference and enhanced the ability to identify partial wave signals.

经济迷信面面观

随着市场经济的发展,一股经济迷信热正在悄然兴起。这是一种附着在经济活动中的落后的文化行为。大致可分为四种类型:一是谐音型。由于人们都想发大财,于是“发”字的粤语谐音走俏,一夜之间阿拉伯数字“8”字身价百倍,几位尾数都是“8”字的轿车号码、电话号码、大哥大号码、BP机号码少则几千元、几万元,多则几十万元。近来又发展到“8”字同其它数字组合.如3388(生生发发)。

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都是“0”在捣鬼

因为实际应用的需要产生了正、负数,正、负数的知识又服务于实际生活,但是在实际应用中一定要做到具体问题灵活分析,尤其不要上0的当,以免得到不合实际的错误答案.下面看刘老师举的两个实例,共同来分析一下.

建立“大表箱体系”的初步设想

当前,用户侧安装的集表箱一般位于每个楼道单元内,这使得表计安装较为分散,在抄核收、表计新装与轮换、采集系统的完善、电力抢修等工作方面有着诸多不便。笔者受到德国大众汽车公司巨型立体车库的启发,在此提出建设大型集中性立体表箱,即＂大表箱体系＂的初步设想：将同一小区内所有用户的电能表全部＂前移＂装设于一栋建筑,即＂大表箱＂内,将电能表按照楼号和层号进行统一排布,原表箱处只保留安装用户侧断路器等设备。

《中图法》电子版编号类型中的层累制类号问题分析

对《中图法》电子版编号类型及类级标注中层累制类号存在的层累制类级错误、层累制误为下借法、层累制误为同借法、层累制误为特殊类号、层累制误为总论复分类号、下借法误为层累制、特殊类号误为层累制等7类问题进行了分析。

Research progress in SAW filter banks

SAW （Surface Acoustic Wave） filter bank is a single input, single or multi-output device consisting of multi-SAW-filters with input interconnection network or switch circuits, and can be divided into two categories： channelizer （multi-output） and switchable （programmable, single output）. The tbrmer is mainly used in military channelized receiver for spectrum analysis; the latter has wide application in frequency synthesizer and frequency-hopping radar and communication system receiver as anti-jamming filter, and has been widely used in various military electronic equipments ever since the 1970s. Research abroad was done mainly by Americans, few documents on related work done by Japan and Russia are available. Domestic research started in the 1980s, mainly by No. 26 Research Institute, China Electronics Technology Group Co., Institute of Acoustics, Chinese Academy of Sciences, No. 23 and No. 25 Research Institute, China Spaceflight Tech. Group Co. This paper first briefly introduces Chinese and foreign research on SAW filter banks; then discusses research progress in device design, the input interconnection network or switch circuit and miniaturization; and ends in a brief perspective of developing trends in future.

Assessing the Quality of Regional Ocean Reanalysis Data from ENSO Signals

The quality of regional ocean reanalysis data for ＂the joining area of Asia and the Indian-Pacific Ocean （AIPO）＂ has been assessed from the perspective of ENSO-related ocean signals. The results derived from the AIPO reanalysis, including SST, sea surface height （SSH）, and subsurface ocean temperature and currents, are compared with those of Hadley Center Sea Ice and Sea Surface Temperature （HadlSST） data set and Simple Ocean Data Assimilation （SODA） reanalysis data. Both the spatial pattern and the characteristics of evolution of the ENSO-related ocean temperature anomalies are well reproduced by the AIPO reanalysis data. The physical processes proposed to explain the life cycle of ENSO, including the delayed oscillator mechanism, recharge-discharge mechanism, and the zonal advection feedback, are reasonably represented in this dataset. However, the westward Rossby wave signal in 1992 is not obvious in the AIPO data, and the magnitude of the heat content anomalies is different from that of the SODA data. The reason for the discrepancies may lie in the different mod- els and methods for data assimilation and differences in wind stress forcing. The results demonstrate the high reliability of the AIPO reanalysis data in describing ENSO signals, implying its potential application value in ENSO- related studies.

Use of low-frequency signals to improve imaging quality under high-velocity basalt

Wave equation wave field numerical modeling technology is applied to the observation that deep layer imaging is difficult below a screening layer of high-velocity basalt. Three simple high-velocity basalt models are designed on the basis of basalt formation characteristics. The analysis of deep-layer reflection seismic signal energy shows that lowfrequency seismic signals are capable of both penetrating the thin high-velocity basalt layer and reducing the diffraction noise caused by the rough surfaces. The simulation experiment of a complete 2D basalt model confirms that the low-frequency signals can be used to boost the quality of deep-layer imaging under the high-velocity basalt layer and achieve good results in low-pass filter processing of actual data.

Generalized Physical Layer Channel Model for RelayBased Super Dense Networks

The κ-μ fading model is an advanced channel model in super dense wireless networks.In this paper,we evaluate the performance of the system over κ-μ fading channel in super dense relay networks with consideration of multiple independent but not necessarily identically distributed(i.n.i.d.) cochannel interference(CCI) under interferencelimited environment.More specifically,we derive a useful and accurate cumulative distribution function(CDF) expression of the end-to-end signal-to-interference plus noise(SINR) ratio.Moreover,we derive novel analytical expressions of the outage probability(OP),average bit error probability(ABEP) and average capacity for binary modulation types and arbitrary positive values of κ-and μ of such system.Furthermore,we propose asymptotic analysis for both the OP and ABEP to give physical insights.A simplified analytical form for the ABEP at high-SNR regimes is provided as well.Finally,the accuracy of the derived expressions is well validated by Monte Carlo simulations.

Cognitive MAC Protocol with Minimum Sampling Time and Cross-Layer Cooperation for Low Signal-to-Noise Ratio Environments

The previous Decentralised Cognitive Medium Access Control(DC-MAC) protocol allows Secondary Users(SUs) to independently search for spectrum access opportunities without the need for a central coordinator.DC-MAC assumes that the detection scheme is ideal at the Physical(PHY) layer.In fact,a more complex detection algorithm is impractical in distributed spectrum sharing scenarios.Energy Detection(ED) at the PHY layer has become the most common method because of its low computational and implementation complexities.Thus,it is essential to integrate the DC-MAC with ED at the PHY layer.However,ED requires the Minimum Sampling Time(MST)duration to achieve the target detection probability in low Signal-to-Noise Ratio(SNR)environments.Otherwise,it cannot achieve the expected detection performance.In this paper,we derive an accurate expression of MST for ED in low SNR environments.Then,we propose an Optimised DC-MAC(ODC-MAC) protocol which is based on MST,and which amends the aforementioned problems of DC-MAC with ED.Moreover,the closed-form expressions for the unreliable data transmission probability are derived for both DC-MAC and ODC-MAC.We show that the simulation results agree well with the theoretical analyses.The proposed ODC-MAC can improve the data transmission reliability and enhance the throughput compared to the performance of the traditional DC-MAC.

Diagnostic efficacy of gadoxetic acid-enhanced MRI for hepatocellular carcinoma and dysplastic nodule

AIM:To evaluate the relationship between the signal intensity of hepatobiliary phase images on gadoxetic acid-enhanced magnetic resonance imaging(MRI)and histological grade.METHODS:Fifty-nine patients with 82 hepatocellular lesions were evaluated retrospectively.Hepatobiliary phase images on gadoxetic acid-enhanced MRI were classified into 3 groups:low,iso or high.Angiographyassisted computed tomography(CT)findings were also classified into 3 groups:CT during arterial portography,and CT hepatic arteriography:A:iso,iso or low;B:slightly low,iso or low;;and C:low,high.We correlated angiography-assisted CT,hepatobiliary phase findings during gadoxetic acid-enhanced MRI and histological grades.Furthermore,correlations between MRI findings and histological grade for each hemodynamic pattern were performed.Correlations among radiologicaland pathological findings were statistically evaluated using the chi-square test and Fisher's exact test.RESULTS:There was a significant correlation between histological grade and hemodynamic pattern(P<0.05).There was a significant correlation between histological grade and signal intensity in the hepatobiliary phase(P<0.05)in group A lesions.There was no significant correlation between histological grade and signal intensity in the hepatobiliary phase in group B or C lesions(P>0.05).CONCLUSION:Signal intensity in the hepatobiliary phase correlated with histological grade in the lesions that maintained portal blood flow,but did not correlate in lesions that showed decreased or defective portal blood flow.

Preliminary evaluation of five elephant grass cultivars harvested at different time for sugar production

Five elephant grass cultivars, Pennisetum purpureum, cv. Huanan （Huanan）, P. purpureum, cv. N51 （N51）, P. purpureum, cv. Sumu No. 2 （Sumu-2）, （ Penniseturn americanum x P. purpureum ） x P. purpureum cv. Guimu No. 1 （Guimu-1） and P. americanum cv. Tift23A x P. purpureum cv. Tilt NS1 （Hybrid Pennisetum）, at three harvest stages were studied. With dilute sulfuric acid pretreatment followed by enzymatic hydrolysis, it is found that cel- lulose conversion of the five elephant grass cultivars harvested in August and September is higher than that har- vested in October. The cellulose conversion for elephant grass cultivars harvested in August and September follows an order of Hybrid Pennisetum 〉 Sumu-2 〉 Huanan 〉 Guimu-1 〉 N51. This may be explained by the fact that lignification is gradually strengthened with time, inhibiting degradation of cellulose and hemicellulose. Moreover, cellulose conversions of Hybrid Pennisetum, Sumu-2 and Huanan harvested in August and September are higher based on hierarchical clustering results.

Design and implementation of a DSP with multi-level low power strategies for cochlear implants

This paper presents the design and implementation of a low power digital signal processor （THUCIDSP-1 ） targeting at application for cochlear implants. Multi-level low power strategies including algorithm optimization, operand isolation, clock gating and memory partitioning are adopted in the processor design to reduce the power consumption. Experimental results show that the complexity of the Continuous Interleaved Sampling （CIS） algorithm is reduced by more than 80 % and the power dissipation of the hardware alone is reduced by about 25% with the low power methods. The THUCIDSP-1 prototype, fabricated in 0.18-μm standard CMOS process, consumes only 1.91 mW when executing the CIS algorithm at 3 MHz.