A Test Pattern Identification Algorithm and Its Application to CINRAD/SA(B) Data

A variety of faulty radar echoes may cause serious problems with radar data applications,especially radar data assimilation and quantitative precipitation estimates.In this study,＂test pattern＂ caused by test signal or radar hardware failures in CINRAD （China New Generation Weather Radar） SA and SB radar operational observations are investigated.In order to distinguish the test pattern from other types of radar echoes,such as precipitation,clear air and other non-meteorological echoes,five feature parameters including the effective reflectivity data percentage （Rz）,velocity RF （range folding） data percentage （RRF）,missing velocity data percentage （RM）,averaged along-azimuth reflectivity fluctuation （RNr,z） and averaged along-beam reflectivity fluctuation （RNa,z） are proposed.Based on the fuzzy logic method,a test pattern identification algorithm is developed,and the statistical results from all the different kinds of radar echoes indicate the performance of the algorithm.Analysis of two typical cases with heavy precipitation echoes located inside the test pattern are performed.The statistical results show that the test pattern identification algorithm performs well,since the test pattern is recognized in most cases.Besides,the algorithm can effectively remove the test pattern signal and retain strong precipitation echoes in heavy rainfall events.

Enhancing SAT-Based Test Pattern Generation

This paper presents modeling tools based on Boolean satisfiability (SAT) to solve problems of test generation for combinational circuits. It exploits an added layer to maintain circuit-related information and value justification relations to a generic SAT algorithm. It dovetails binary decision graphs (BDD) and SAT techniques to improve the efficiency of automatic test pattern generation (ATPG). More specifically, it first exploits inexpensive reconvergent fanout analysis of circuit to gather information on the local signal correlation by using BDD learning, then uses the above learned information to restrict and focus the overall search space of SAT-based ATPG. Its learning technique is effective and lightweight. The experimental results demonstrate the effectiveness of the approach.

Study on Test Compaction in High-Level Automatic Test Pattern Generation (ATPG) Platform

Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic test pattern generation (ATPG). In addition, ATPG needs to deal with new defects caused by process variation when IC is shrinking. To reduce the computation effort of ATPG, test generation could be started earlier at higher abstraction level, which is in line with top-down design methodology that has become more popular nowadays. In this research, we employ Chen’s high-level fault model in the high-level ATPG. Besides shorter ATPG time as shown in many previous works, our study showed that high-level ATPG also contributes to test compaction. This is because most of the high-level faults correlate with the gate-level collapsed faults especially at input/output of the modules in a circuit. The high-level ATPG prototype used in our work is mainly composed by constraint-driven test generation engine and fault simulation engine. Experimental result showed that more reduced/compact test set can be generated from the high-level ATPG.

Efficient Static Compaction of Test Patterns Using Partial Maximum Satisfiability

Static compaction methods aim at finding unnecessary test patterns to reduce the size of the test set as a post-process of test generation.Techniques based on partial maximum satisfiability are often used to track many hard problems in various domains,including artificial intelligence,computational biology,data mining,and machine learning.We observe that part of the test patterns generated by the commercial Automatic Test Pattern Generation(ATPG)tool is redundant,and the relationship between test patterns and faults,as a significant information,can effectively induce the test patterns reduction process.Considering a test pattern can detect one or more faults,we map the problem of static test compaction to a partial maximum satisfiability problem.Experiments on ISCAS89,ISCAS85,and ITC99 benchmarks show that this approach can reduce the initial test set size generated by TetraMAX18 while maintaining fault coverage.

Ultrasonic Testing Combined with Pattern Recognition for the Detection of Kissing Bonds

Kissing bonds are defects in the adhesive bonds with intimate contact of touching surface but considerably lowered shear strength. Their detection specifically in the aerospace area is so not satisfactory. Usually, kissing bonds are inconspicuous in ultrasonic C-scans. However, the determination of attributes in the time domain and the frequency domain of an ultrasound signal provides the opportunity to derive a pattern for bonded area. Deviations from the pattern found in inconspicuous bonding areas indicate kissing bonds. The survey described here deals with the manufacturing of adhesively joint samples that purposefully include kissing bonds, as well as potential solutions for detecting them through ultrasonic testing combined with pattern recognition. The properties of the epoxy-based adhesive were varied by changing the mixing ratios between resin and hardener. Samples with a mixing ratio far apart from the manufacturer’s recommendation with an inconspicuous appearance in a C-scan, but low shear strength values were taken for further evaluation. After a definition and learning phase, a 100 percent hit rate to separate good bondings from kissing bonds could be derived in a blind test. The discriminating feature found is due to the frequency shift between good and kissing bonds as well as the relative amplitude of the second peak.

基于虚拟仪器的集成运放自动测试教学辅助平台设计

为降低设备故障对模拟电子技术实验教学效率的影响,基于虚拟仪器技术设计了一种集成运放自动测试教学辅助平台。利用集成化虚拟仪器实验平台NI ELVIS II进行数据传输,设计了测试电路板卡;利用Lab-VIEW软件设计了仪器面板和平台软件部分。使用集成运放μA714芯片对平台进行了测试,并在模拟电子技术的实际教学中进行了效果验证。测试和实际使用结果表明,该平台可以准确检测出故障芯片,正确率>95%;相比于未使用本平台时,师生使用本平台进行实验的准确率提升超过20%,耗时降低超过20%。

鄂尔多斯盆地东缘深部煤层气开发先导试验效果与启示

鄂尔多斯盆地东缘大宁-吉县区块深部煤层气勘探开发取得突破对煤层气产业带来重大影响,引起业内广泛关注和跟进。前期一些学者对深部煤层气勘探开发理论技术难点与对策开展了研究,但缺乏对典型气田开发先导试验系统总结。通过深入剖析深部煤层气地质特征与效益开发难点,总结大宁-吉县区块开发先导试验项目取得的进展和成效,明确开发规律并提出效益开发对策。结果表明:(1)深部煤层具有广覆式发育、含气性好、游离气含量高、保存条件好、煤体结构好、脆性指数高、顶底板封盖性强等地质特征,但微构造发育、渗透性极差、矿化度高等因素制约了深部煤层气效益开发;(2)不同地质条件下气井生产特征差异较大,通过先导试验落实气井产能和适应性开发技术对策,采用滚动开发模式可有效降低煤层强非均质性带来的开发风险;(3)开展地质-工程一体化井网优化设计,构建井网与缝网高度弥合的人造气藏,可实现资源动用和采收率最大化;(4)“长水平段+多段多簇+大砂量”的大规模、大排量极限体积压裂技术可增大有效改造体积和井控储量,大幅提高单井产量;(5)深部煤层气井具有“见气时间短、上产速度快、初期产量高、递减快”的生产特征,可实现短期快速规模上产,但气田长期稳产需持续新井投入;(6)前期开发成本偏高,实现效益开发需不断提高工程作业效率、降低开发成本。综合认为,深部煤层气资源品质好,可动用性强,具备快速推广复制条件,大宁-吉县区块深部煤层气开发实践可为国内其他区块深部煤层气规模动用提供技术借鉴,对加快深部煤层气规模勘探开发具有重要意义。

Reporting Children’s Development below the Test Floor: Looking Back and Forth to Describe Individual Strengths and Needs

The test floor effects seen in standardised tests lead to a standardised score of 1 or less with a flat profile that hides a child’s individual strengths and needs. The Griffiths III community of practitioners requested advice on the reporting of children’s development below the floor of the test, so that individual strengths and needs can be described. This paper reports the third phase of research following an earlier Scoping Review and a wider literature review. To confirm quality control, Phase 3 was conducted in a retrospective manner using the same methodology as the earlier phases but in a reverse direction. Peer reviewer comments and key elements from the Scoping Review and keywords from the publications were tabulated. Data analysis included a change of perspective to that of the child and their individual rights with respect to the literature themes already described in Phase 2. These confirmed that there is little specific guidance in the literature, but that computational advances for homogeneous populations and especially disaggregated data offer some solutions. A greater balance between broad biopsychosocial models and standardised models of assessment should be sought by practitioners together with the use of disaggregated data to highlight issues that pertain to individual subsets of results. This will ensure that the child’s right for their individual strengths and needs to be described together with a plan for management, may be met.

信江八字嘴枢纽工程整体水工模型试验研究

根据工程建设的需要,为了全面验证枢纽建筑物整体布置方案的合理性,对江西信江八字嘴枢纽工程进行了整体水工模型试验。通过模型试验研究其水力特性和流态,在满足消能防冲的条件下,创造安全的通航水流条件,确定了枢纽整体布置形式和消能工体型。试验成果优化了枢纽建筑物布置方案,为工程设计提供了技术依据。

泥石流中球形巨石运动规律模型试验研究

该研究通过室外水槽模型试验,模拟了不同直径巨石与不同密度泥石流完全固液耦合作用下的运动状态,分析了泥石流沟内巨石在泥石流中的运动模式、运动的影响因素及其在泥石流中的受力情况,并探讨了泥石流密度与巨石粒径对其运动速度的影响。研究结果表明:巨石在运动过程中可能出现滚动、跳跃与滑动等运动模式,巨石出现的运动模式同泥石流的密度以及巨石粒径有关;巨石的直径越大,运动速度越小,它在泥石流中的运动模式越简单,越倾向于发生滚动运动,在泥石流流体中的跟随性越好,速度比n越容易趋近于1;巨石粒径对巨石运动速度的影响大于泥石流密度对它的影响。

基于ATE的千级数量管脚FPGA多芯片同测技术

随着超大规模FPGA芯片技术发展,芯片管脚数量提升到1000以上,如何实现超大规模多引脚FPGA芯片高效测试成为ATE在线测试难点。针对一款千级数量管脚超大规模的FPGA芯片,基于FPGA的可编程特性,采用多芯片有效pin功能并行测试和单芯片全pin电性能参数测试相结合的方法进行ATE测试,实现了千级数量管脚FPGA芯片的4芯片同测,测试效率提升3倍多。

110 kV干式空心并联电抗器振动台试验与易损性研究

电抗器是变电站的重要设备之一,上部线圈由底部陶瓷绝缘子支撑,整体尺寸大、重心高。由于结构形式的特殊性,其在地震作用下的动力响应较为复杂。本文对110 kV干式空心并联电抗器进行了振动台试验研究,通过白噪声测定了电抗器的自振频率和阻尼比;在0.15g和0.5g人工地震动输入下,测量了电抗器关键部位的应变、加速度和位移响应,分析了电抗器在地震作用下的动力响应规律,探讨了电抗器的可能破坏模式,进一步计算了电抗器的地震易损性曲线。研究结果表明:电抗器的动力特性近似于单自由度体系,一阶自振频率为3.3 Hz,阻尼比为3.9%;电抗器在地震作用下的变形主要发生在绝缘子以及绝缘子-线圈连接部位,上部线圈可认为是刚体;与绝缘子相比,绝缘子-线圈连接部位的刚度较小,变形更集中,是电抗器的薄弱部位;0.15g人工地震动试验后,电抗器自振频率下降3.6%,0.5g人工地震动试验后,电抗器自振频率下降6.3%;根据绝缘子实测应变,考虑地震作用与其他荷载产生的总应力,电抗器的安全系数为2.14,仍然具有一定的安全储备;基于试验结果计算电抗器的地震易损性,抗震能力中值为0.965g,对数标准差为0.4。

测试图形程序的进一步研究：PATTERN抽象及再实现

异构自动测试仪（ＡＴＥ）之间的测试图形程序移植是一项难度很高的工作。通常采用的方法是对测试图形向量进行逐条直移。这样，如果在异构ＡＴＥ测试图形语言之间找不到对应的语言成分，将导致实际有可能成功的移植失败。并且，即使这样移植成功，移植的测试图形程序可保证词法和语法的正确性，但在大多数情况下，这些程序仍不能在目标ＡＴＥ上正确运行。本文在详细分析了传统移植方法后，提出一种基于异构ＡＴＥ功能对等的移植方法，使测试图形程序在移植前后保持其意义的一致性。利用这种方法，可以大大提高测试图程序的可移植性。

运载火箭海上发射测发流程现状及未来发展探析

海上发射已呈现多型号、高密度、常态化的态势,测试发射流程的精简高效程度,直接影响着海上发射的频次和效能。本文分析了运载火箭海上测试发射流程现状,理清了国内当前典型海上测试发射流程及不同发射样式测试发射流程的区别,最后针对当前测试发射流程的不足,提出了建立行业标准、探索一船多箭新样式、“天基测发”流程等的发展方向建议。

Dependence of single event upsets sensitivity of low energy proton on test factors in 65 nm SRAM

In order to accurately predict the single event upsets （SEU） rate of on-orbit proton, the influence of the proton energy distribution, incident angle, supply voltage, and test pattern on the height, width, and position of SEU peak of low energy protons （LEP） in 65 nm static random access memory （SRAM） are quantitatively evaluated and analyzed based on LEP testing data and Monte Carlo simulation. The results show that different initial proton energies used to degrade the beam energy will bring about the difference in the energy distribution of average proton energy at the surface and sensitive region of the device under test （DUT）, which further leads to significant differences including the height of SEU peak and the threshold energy of SEU. Using the lowest initial proton energy is extremely important for SEU testing with low energy protons. The proton energy corresponding to the SEU peak shifts to higher average proton energies with the increase of the tilt angle, and the SEU peaks also increase significantly. The reduction of supply voltage lowers the critical charge of SEU, leading to the increase of LEP SEU cross section. For standard 6-transitor SRAM with bit-interleaving technology, SEU peak does not show clear dependence on three test patterns of logical checkerboard 55H, all＂ 1＂, and all ＂0＂. It should be noted that all the SEUs in 65 nm SRAM are single cell upset in LEP testing due to proton＇s low linear energy transfer （LET） value.

基于本体的软件安全漏洞模式

针对软件缺陷与软件安全漏洞研究中存在的概念混淆问题,对DevSecOps框架下的软件安全漏洞生存期进行研究。基于软件安全漏洞生存期引入漏洞的4种情况,结合漏洞的特点提出软件安全漏洞模式定义,并采用本体方法进行表示。本体是概念化明确的规范说明,能够解决软件安全漏洞研究领域存在的二义性、不一致性、难以共享,以及由分析知识分散所导致的对人员知识和经验过度依赖的问题。以软件安全漏洞模式的分析为基础,兼顾宏观事件表现,构造漏洞分析的3层模型,即事件表示层、行为动作层和漏洞技术层。实例应用所构模型的层次结构实施渗透测试,包括安全风险分析、威胁建模、漏洞分析及渗透攻击等。实验结果表明:基于所提软件安全漏洞模式本体库的改进渗透测试具有科学性和有效性。

1966—2018年岷江流域极端气温事件时空变化特征

在全球变暖背景下,极端气候事件问题逐渐显著,岷江流域作为川滇生态屏障区的重要组成部分,受气候变化的影响较大,研究该流域极端气候事件时空变化规律,能为未来气象灾害防治等提供科学依据。基于1966—2018年岷江流域62个气象站点的气温资料,选用“气候变化检测和指标”专家组所确定的16个极端气温指数,采用一元回归方程、Sen斜率、反距离权重空间插值法和Mann-Kendall检验法分析极端气温指数的时空变化规律。结果显示:岷江流域极端气温事件存在明显的时间变化特征,并且变化趋势在空间分布上存在一定的差异性。结果表明:(1)岷江流域极端高温事件显著增加,极端低温事件显著减少;极端气温指数的突变年份主要集中在1990—2000年左右,其中极端低温指数均在突变后呈现显著下降趋势,极端高温指数、极值指数、其他指数中除了日较差指数,均在突变后呈显著上升趋势;(2)极端低温指数在流域内大部分地区呈下降趋势,平均年变化率为-0.98 d·(10a)^(-1);极端高温指数、极值指数和作物生长期指数大部分地区呈上升趋势,其中极端高温指数上升趋势在流域内呈西低东高的分布,作物生长期指数在流域内呈北高南低的分布;日较差指数在流域上游地区呈下降趋势,中下游地区呈上升趋势。

基于机械臂毫米波天线测试系统设计与实现

测试天线波瓣图是分析天线性能的重要方法,随着毫米波天线的大量应用,如何开发出部署灵活,成本较低的毫米波天线测试系统,成为毫米波天线大批量生产的关键,针对此问题,开发出了基于机械臂的毫米波天线测试系统;同时,针对目前平面天线测试系统测试功能单一的问题,基于机械臂的毫米波天线测试系统,不仅能够执行平面近场测试,还能够进行柱面近场、球面近场以及远场测试任务;通过对机械臂实际的精度测量实验和机械臂关键运动参数的计算,验证了基于机械臂测量毫米波天线的可行性并为系统软件设计提供了理论基础;通过与传统平面天线测试系统测试数据比较,增益偏差0.73%,波束宽度偏差1.4%,副瓣偏差1.37%,测试结果一致性较好;实际应用表明该系统能够满足毫米波天线的测试需求,为毫米波天线测试提供了重要手段。

UHPC-NC组合箱梁顶板界面抗剪性能试验研究

为了研究超高性能混凝土(UHPC)与普通混凝土(NC)组合箱梁的界面抗剪性能,该文设计了3类界面处理方式不同的试件,分别为不处理类、凿毛类、涂缓凝剂+水冲洗类,同时进行了UHPC与NC的组合推出试验,分析3类试件的破坏形态和抗剪性能.试验结果表明:UHPC与NC组合结构进行界面处理后,推出试件的破坏形态为普通混凝土侧的拔出破坏,与界面不处理的破坏形态相同,且各类试件的初始剪切刚度相近.但不同界面处理方式对试件的平均抗剪强度影响较大,进行界面处理后相较于不处理时的平均抗剪强度大幅提高,均为不处理时的4倍以上.

中国大豆需水量时空演变趋势分析

[目的]探究中国大豆需水量的时空演变趋势。[方法]基于1971-2020年气象数据,采用作物系数法计算中国大豆需水量,采用Mann-KendaⅡ趋势检验与重标极差(R/S)分析中国大豆需水量及水分亏缺值的时空变化。[结果]中国大豆全生育期需水量、水分亏缺值分别为382、111 mm,总体上不缺水,但在北方干旱半干旱区、青藏高原区、黄土高原区的干旱缺水形势严重。在北方干旱半干旱区东部、东北平原区南部、黄淮海平原区西部、云贵高原区南部、华南区,大豆干旱缺水形势趋于恶化。未来在北方干旱半干旱区东部、云贵高原区西南部、青藏高原区西部等缺水地区,干旱大豆生育期内缺水形势呈恶化趋势,而在黄淮海地区西部、云贵高原区东南部、长江中下游地区南北部及华南区西部等丰水地区,大豆生育期内存在潜在的缺水危机。[结论]在东北平原区南部、黄淮海平原西部及长江中下游地区南北部等大豆扩种区域,未来大豆干旱形势呈加剧趋势,在这些地区扩大大豆种植面积时需采用节水措施以确保水资源可持续利用。