An Efficient and Secure Privacy-Preserving Federated Learning Framework Based on Multiplicative Double Privacy Masking

With the increasing awareness of privacy protection and the improvement of relevant laws,federal learning has gradually become a new choice for cross-agency and cross-device machine learning.In order to solve the problems of privacy leakage,high computational overhead and high traffic in some federated learning schemes,this paper proposes amultiplicative double privacymask algorithm which is convenient for homomorphic addition aggregation.The combination of homomorphic encryption and secret sharing ensures that the server cannot compromise user privacy from the private gradient uploaded by the participants.At the same time,the proposed TQRR(Top-Q-Random-R)gradient selection algorithm is used to filter the gradient of encryption and upload efficiently,which reduces the computing overhead of 51.78%and the traffic of 64.87%on the premise of ensuring the accuracy of themodel,whichmakes the framework of privacy protection federated learning lighter to adapt to more miniaturized federated learning terminals.

20号钢无缝钢管腐蚀穿孔失效原因分析

为了确定西部某油田无缝钢管腐蚀穿孔失效的原因,对失效的无缝钢管样品进行了外观、理化性能、金相组织、腐蚀产物元素和成分等的试验分析。试验分析结果表明,失效无缝钢管的化学成分和布氏硬度试验结果均符合GB/T 12459—2017标准的要求,3^(#)无缝钢管样品的伸长率不符合该标准的要求;无缝钢管材料中含有少量的非金属夹杂物,金相组织为P+F;腐蚀坑中的物质主要由O、Fe、S、Cl、Si、Ca和C等元素构成;腐蚀产物主要由Fe_(3)O_(4)、Fe_(2)O_(3)和FeOOH组成。根据腐蚀产物的化学成分,该无缝钢管腐蚀穿孔主要是由土壤中的溶解氧腐蚀所引起,失效形式为无缝钢管外壁局部腐蚀导致的腐蚀穿孔。

某高压燃气管道弯管腐蚀泄漏原因分析

某城市燃气管道中的弯管出现了泄漏,为了确定该弯管的泄漏原因,对泄漏弯管的外观形貌、理化性能、金相组织、腐蚀产物和化学成分等进行了试验分析。结果表明,弯管材料的化学成分、拉伸、夏比冲击及维氏硬度试验结果符合SY/T 5257—2012标准的要求;但弯管的壁厚尺寸不符合SY/T 5257—2012要求。防腐层弯曲与耐浸泡试验结果不符合GB/T 23257—2017标准的要求。弯管泄漏的主要原因是弯管外表面的3PE防腐层局部破损后,土壤中的溶解氧形成的电化学腐蚀使弯管外表面产生了微小的腐蚀坑并逐渐向内壁扩展,使腐蚀坑处的弯管壁厚逐渐减小,最终腐蚀坑穿透弯管管壁并使弯管发生了泄漏。

凹点搜寻下重叠区域图像自动分离方法仿真

重叠区域图像分离是图像处理技术中的一个重要环节,在医疗诊断、工业加工和军事防御等众多领域占据重要地位。针对当前方法在对重叠区域图像进行分离时,过于依赖极限腐蚀运算,一旦极限腐蚀运算没有较好的将图像重叠区域腐蚀开,无法得到准确的距离标记,将会导致重叠区域图像无法有效分离。提出一种基于凹点搜寻的重叠区域图像自动分离方法,在低尺度空间上,对重叠区域图像轮廓曲率进行计算;利用高斯函数的宽度参量控制重叠区域轮廓的平滑程度;计算获得重叠区域每个边缘像素的曲率后,去除曲率大于0的凸点,选取曲率极小值的点作为候选凹点,同时去除虚假凹点,完成重叠区域图像的凹点检测;根据重叠区域图像凹点个数与目标对象个数之间的对应关系确定重叠类型,给出了重叠区域图像的不同凹点匹配规则;通过连接的匹配凹点,实现重叠区域图像的自动分离。仿真测试结果证明,所提方法能够实现图像不同重叠类型的有效分离,分离对象具有较高的信噪比,结构相似性和品质,且没有发生较大形变。

Quantitative computed tomography analysis for stratifying the severity of Coronavirus Disease 2019

To examine the feasibility of using a computer tool for stratifying the severity of Coronavirus Disease 2019(COVID-19)based on computed tomography(CT)images.We retrospectively examined 44 confirmed COVID-19 cases.All cases were evaluated separately by radiologists(visually)and through an in-house computer software.The degree of lesions was visually scored by the radiologist,as follows,for each of the 5 lung lobes:0,no lesion present;1,<1/3 involvement;2,>1/3 and<2/3 involvement;and 3,>2/3 involvement.Lesion density was assessed based on the proportion of ground-glass opacity(GGO),consolidation and fibrosis of the lesions.The parameters obtained using the computer tool included lung volume(mL),lesion volume(mL),lesion percentage(%),and mean lesion density(HU)of the whole lung,right lung,left lung,and each lobe.The scores obtained by the radiologists and quantitative results generated by the computer software were tested for correlation.A Chi-square test was used to test the consistency of radiologist-and computer-derived lesion percentage in the right/left lung,upper/lower lobe,and each of the 5 lobes.The results showed a strong to moderate correlation between lesion percentage scores obtained by radiologists and the computer software(r ranged from 0.7679 to 0.8373,P<0.05),and a moderate correlation between the proportion of GGO and mean lesion density(r=-0.5894,P<0.05),and proportion of consolidation and mean lesion density(r=0.6282,P<0.05).Computer-aided quantification showed a statistical significant higher lesion percentage for lower lobes than that assessed by the radiologists(x^2=8.160,P=0.004).Our experiments demonstrated that the computer tool could reliably and accurately assess the severity and distribution of pneumonia on CT scans.

Research on Data Fusion of Adaptive Weighted Multi-Source Sensor

Data fusion can effectively process multi-sensor information to obtain more accurate and reliable results than a single sensor.The data of water quality in the environment comes from different sensors,thus the data must be fused.In our research,self-adaptive weighted data fusion method is used to respectively integrate the data from the PH value,temperature,oxygen dissolved and NH3 concentration of water quality environment.Based on the fusion,the Grubbs method is used to detect the abnormal data so as to provide data support for estimation,prediction and early warning of the water quality.

潜油电泵气体处理器失效原因分析

为分析西部某油田潜油电泵中气体处理器穿孔及断裂原因,对潜油电泵进行外观检验、壁厚测量、磁粉探伤、理化检验、金相组织及扫描电镜观察等测试。结果表明:该电泵穿孔的主要原因是由于内螺纹处产生了穿透性裂纹所致,而螺纹连接处存在未啮合的内螺纹导致形成穿透性裂纹。电泵壳体断裂属于疲劳断裂,其壳体与内衬层缝隙内发生腐蚀以及组织粗大不均匀性是导致疲劳断裂的主要原因。

N80Q套管螺纹粘扣原因分析

某油田N80Q套管发生粘扣失效事故。通过宏观形貌观察、理化性能检验、金相分析、实物上卸扣试验及螺纹参数测量,分析了该套管的粘扣原因。结果表明,该N80Q套管化学成分分析、拉伸及冲击试验结果均符合标准要求,螺纹粘扣的主要原因为现场上卸扣过程中套管钳夹持位置不当、对扣不准及螺纹错扣等操作不当。

某油田ERW钢管管体泄漏失效分析

为分析东北某油田ERW钢管在输送油气过程中管体泄漏失效原因,对ERW钢管失效样品进行宏观形貌检验、理化检验、金相组织及扫描电镜分析等试验。结果表明,该ERW钢管管体泄漏失效的主要原因是管道底部残留积液和空气试压中的O2和CO2导致的腐蚀,腐蚀介质为大体积的O2和CO2在小体积的残留积液中形成持续饱和的腐蚀性水溶液,腐蚀类型为腐蚀产物膜的膜下腐蚀。建议对后续再建管线,试压前对管线进行热风吹扫;如果管线不及时投用,建议采用氮气保压。

N80钢防砂管腐蚀穿孔原因分析

为了分析西部某油田N80钢防砂管表面腐蚀穿孔及断裂的原因,对防砂管进行了宏观检查、壁厚测量、磁粉探伤、理化检验及扫描电镜(SEM)观察等综合分析。结果表明,该防砂管腐蚀穿孔的主要原因是基管(碳钢)和护管(不锈钢)浸泡在同一电解质(井下采出液)中,由于碳钢与不锈钢之间存在电位差,导致相互之间发生电偶腐蚀,使得电位较低的基管(碳钢)首先发生腐蚀,最终腐蚀穿孔而断裂。

直缝埋弧焊钢管穿孔原因

某在用管道在试压过程中发生穿孔泄漏,采用宏观观察、化学成分分析、力学性能试验、金相检验、扫描电镜分析等方法进行了研究。结果表明:该钢管穿孔的主要原因是管体外表面受到高温烧伤,且在试压前管体外表面已经烧伤穿透,进而钢管在试压过程中发生泄漏。

RNF187 governs the maintenance of mouse GC-2 cell development by facilitating histone H3 ubiquitination at K57/80

RING finger 187(RNF187),a ubiquitin-ligating(E3)enzyme,plays a crucial role in the proliferation of cancer cells.However,it remains unclear whether RNF187 exhibits comparable functionality in the development of germline cells.To investigate thepotential involvement of RNF187 in germ cell development,we conducted interference and overexpression assays using GC-2 cells,a mouse spermatocyte-derived cell line.Our findings reveal that the interaction between RNF187 and histone H3 increases theviability,proliferation,and migratory capacity of GC-2 cells.Moreover,we provide evidence demonstrating that RNF187 interactswith H3 and mediates the ubiquitination of H3 at lysine 57(K57)or lysine 80(K80),directly or indirectly resulting in increasedcellular transcription.This is a study to report the role of RNF187 in maintaining the development of GC-2 cells by mediatinghistone H3 ubiquitination,thus highlighting the involvement of the K57 and K80 residues of H3 in the epistatic regulation of genetranscription.These discoveries provide a new theoretical foundation for further comprehensive investigations into the functionof RNF187 in the reproductive system.

Forming and breaking the ceiling of inlet gas velocity regarding to separation efficiency of cyclone

The maximum-efficiency inlet velocity(MEIV)is a ceiling of inlet gas velocity that defines separation efficiency during cyclone design and operation.Experiment and computational fluid dynamics(CFD)simulation exhibited that an apex cone at the dust outlet can break the ceiling and improve the sepa-ration efficiency.The phenomenon is closely related to the effect of excessive high inlet gas velocity on the back-mixing escape of fine particles,which is the final result of back mixing,entrainment by the rapid upward airflow,and secondary separation of the inner vortex.In the center of the inner vortex,the airflow rotates slowly and moves rapidly upward.This elevator type of airflow delivers re-entrained particles to the vortex finder.A higher inlet gas velocity accelerates the elevator,causing more entrained particles to escape.This explains the decrease in efficiency at an excessively high inlet gas velocity.When an apex cone is installed at the dust outlet,the back-mixing is significantly weakened because the vortex core is bounded to the center of separator,while the transport effect of rapid upward airflow is weakened by the decrease in axial velocity in the center.Therefore,particle escape is weakened even at excessive high inlet gas velocities.Instead,the centrifugal effect is enhanced because of increased tangential velocity of the gas and particles.Consequently,the ceiling of inlet gas velocity is broken.

Topological Equivalence Theorem and Double-Copy for Chern-Simons Scattering Amplitudes

We study the mechanism of topological mass generation for 3-dimensional Chern-Simons gauge theories and propose a brand-new topological equivalence theorem to connect scattering amplitudes of the physical gauge boson states to that of the transverse states under high-energy expansion.

基于时空图的行人轨迹预测

在自动驾驶技术中,行人轨迹预测的结果往往会影响到自动驾驶的安全性。行人轨迹预测技术目前面临着在实际场景中应用时与他人的交互问题,需要在预测轨迹的同时考虑社会交互性与逻辑自洽。因此,在之前的预测模型上做改进,得到了更好的预测效果。具体思路就是,首先用一个长短时记忆网络(Long short term memory network,LSTM)模型建立行人之间相互作用的时间相关性;然后,用图注意网络(Graph attention network,GAT)将长短时记忆网络的隐藏状态信息进行融合,最后得到所需要的预测轨迹信息。本文的轨迹预测模型在苏黎世联邦理工大学行人数据集(Eidgenossische Technische Hochschule Zürich pedestrians dataset,ETHD)和塞浦路斯大学行人数据集(University of Cyprus pedestrians dataset,UCYD)上进行模型训练与测试,实验结果表明,所提出的方法优于现行方法且平均精度提高13.6%。

基于计算机辅助测量对正常学龄前儿童肺血管体积的研究

目的基于胸部CT定量测量探讨正常学龄前儿童肺内血管体积(IPVV)随生长发育的变化趋势。方法回顾性收集"数字肺"影像数据库2014年1月至2017年5月行胸部CT检查且结果正常的407例正常学龄前儿童的CT资料,男236例、女171例,月龄36(21,50)个月,范围1~72个月。使用"数字肺"肺血管自动检测工具分割肺内血管,并得到全肺、右肺、左肺及各肺叶的IPVV,计算IPVV上/下及IPVV左/右。根据月龄将受试者分为婴儿期(0~12个月)、幼儿期(13~36个月)和学龄前期(37~72个月),分别为30例(男17例、女13例)、175例(男95例、女80例)、202例(男124例、女78例)。用Spearman相关性分析评价IPVV与月龄的相关性。采用单因素方差分析或Kruskal-WallisH检验比较不同月龄段间、采用独立样本t检验或Mann-WhitneyU检验比较不同性别间IPVV、IPVV上/下及IPVV左/右的差异,并建立各个月龄段正常学龄前儿童IPVV的正常参考值范围。结果全肺、右肺、左肺及各个肺叶的IPVV与月龄均呈正相关,相关系数男性为0.638~0.820,女性为0.683~0.791(P均<0.001)。0~12个月的男、女童间全肺、右肺、左肺及各肺叶IPVV差异均无统计学意义(P均>0.05),13~36个月男、女童间全肺、右肺、左肺及各肺叶IPVV差异均有统计学意义(P均<0.05),37~72个月男、女童间全肺、右肺、左肺、双肺上叶IPVV差异均有统计学意义(P均<0.05)。男、女童3个月龄段间右肺IPVV上/下(χ^(2)=14.00、12.87,P=0.001、0.002)和左肺IPVV上/下差异均有统计学意义(χ^(2)=6.65、22.84,P=0.036、<0.001),且随着月龄的增长呈递减趋势;同月龄段男、女童间IPVV上/下差异无统计学意义(P均>0.05)。不同月龄段及各月龄段不同性别间IPVV左/右差异均无统计学意义(P均>0.05)。最后计算出婴儿期、幼儿期、学龄前期不同性别IPVV的正常参考值范围。结论正常学龄前儿童肺血管的增长与月龄呈正相关,婴儿期男、女间IPVV无显著差异,而在幼儿期和学龄前期男童IPVV大于女童;下肺IPVV增长的速度快于上肺,而在左右肺之间无明显差异。

Strawberry Notch 1 (SBN01) promotes proliferation of spermatogonial stem cells via the noncanonical Wnt pathway in mice

While it is known that spermatogonial stem cells (SSCs) initiate the production of male germ cells, the mechanisms of SSC self-renewal, proliferation, and differentiation remain poorly understood. We have previously identified Strawberry Notch 1 (SBN01), a vertebrate strawberry notch family protein, in the proteome profile for mouse SSC maturation and differentiation, revealing SBN01 is associated with neonatal testicular development. To explore further the location and function of SBN01 in the testes, we performed Sbnol gene knockdown in mice to study the effects of SBN01 on neonatal testicular and SSC development. Our results revealed that SBN01 is required for neonatal testicular and SSC development in mice. Particularly, in vitro Sbnol gene knockdown with morpholino oligonucleotides caused a reduction of SSCs and inactivation of the noncanonical Wnt pathway, through Jun N-terminal kinases. Our study suggests SBN01 maintains SSCs by promoting the noncanonical Wnt pathway.

Ultra-flat broadband micro wave frequency comb generation based on optical frequency comb with a multiple-quantumwell electro-absorption modulator in critical state

In this paper,we proposed a novel ultra・flat broadband microwave frequency comb(MFC)generation based on optical frequency comb(OFC)with a multiplequantum-well electroabsorption modulator(MQW-EAM)in critical state.The scheme is simple and easy to adjust.The performance of the MFC generation scheme is investigated using software Optisystem.The results show that the comb spacing of MFC can be adjusted from 5 to 20 GHz by changing RF signafs frequency and the MFC is almost independent on the linewidth of the tunable laser diode.The performance of the MFC can be improved by reasonably increasing the voltage of the RF,the smallsignal gain of the Erbium-doped fiber amplifier(EDFA)and the responsivity of the photodetector.The MFC generated by this scheme has 300 GHz effective bandwidth with 15 comb lines,whose power variation is 0.02 dB,when the components9 parameters in the Optisystem are set as follows:the power of tunable laser diode(TLD)is 0 dBm,the wavelength is 1552.52 nm,and linewidth is 1 MHz;RF signaPs frequency is 20 GHz and the voltage is 10 V;the reverse bias voltage of MQW-EAM is 6.92 V;the small-signal gain of the EDFA is 40 dB;the responsivity of the photodetector(PD)is 1 A/W.

Regio-and stereo-selective olefinic C–H functionalization of aryl alkenes in ethanol

We report on N,N-bidentate-chelation-assistedα-and β-olefinic C–H alkenylation of aryl alkenes in ethanol to afford aryl dienes/trienes with excellent regio-and stereo-selectivities.The reaction of 2-alkenyl benzylamine and benzoic acid derived substrates proceeded through six-membered exo-cyclo-metallation and seven-membered endo-cyclometallation.The aerobic protocols feature wide functional-ity tolerance,high selectivities and yields,mild conditions and scalable preparation,and the directing group can be easily removed to afford Boc-protected amine by simple reduction.