Stratigraphy of the MSGBC Basin in the Western Part of Thies by Pixelation and Website Simulation (Senegal, West Africa)

During this research work we developed another approach to digital mapping using the pixelation technic. This unprecedented digital mapping of the basin MSGBC in Senegal required the compilation of numerous geological data consisting of seismic lines and oil and hydraulic log reports. These spatial reference data include geological information from the surface to the top of the Campanian. The mapped terrains are composed of the Post-Paleocene Complex (PPC), the Paleocene, the Maastrichtian, and the Campanian. The nearest neighbor method has been used to establish the spatial distribution of the different geological formations. Histograms of values were used to determine the confidence intervals of the mapping. They were used to locate areas of low relative error and to apply the 3D digital mapping technique. For instance, Diender Guedj has been mapped at 1:25,000. The result of this mapping is extracted and processed using the DBMS (MySQL) software. The latter allowed both to determine Paleocene gab and update data. And then the database is processed. The programming languages PHP and Javascript have been used to simulate a website.

结合Pixel2style2Pixel的年龄转化方法

年龄转化在刑侦、人脸识别等领域有着重要作用。常见的年龄转化方法需要使用成对带有年龄注释的数据集进行训练,并且存在生成图像质量低、年龄语义信息不够解耦等问题。针对上述问题,在Pix2style2Pix的训练框架中,引入年龄识别、contextual损失函数,对整体损失函数做出符合年龄转化的改进,提取年龄信息并保证图像质量。改进编码网络配合损失函数对潜在空间的图像进行编辑,提出一种基于Pixel2style2Pixel的年龄转化方法。通过FFHQ、CelebA数据集,对所提方法进行验证,实验结果表明,在不采用成对年龄注释的训练集下,改进后的损失函数能生成更符合期望年龄的转化图像,人脸相似度距离为0.346、FID为45.69、SSIM为0.593 6、PSNR为19.64 dB,均优于对比方法,证明所提方法能够生成高质量、年龄语义高度解耦的转化结果。

Monitoring Surface Deformation Using Distributed Scatterers InSAR

In the past two decades,extensive and in-depth research has been conducted on Time Series InSAR technology with the advancement of high-performance SAR satellites and the accumulation of big SAR data.The introduction of distributed scatterers in Distributed Scatterers InSAR(DS-InSAR)has significantly expanded the application scenarios of InSAR geodetic measurement by increasing the number of measurement points.This study traces the history of DS-InSAR,presents the definition and characteristics of distributed scatterers,and focuses on exploring the relationships and distinctions among proposed algorithms in two crucial steps:statistically homogeneous pixel selection and phase optimization.Additionally,the latest research progress in this field is tracked and the possible development direction in the future is discussed.Through simulation experiments and two real InSAR case studies,the proposed algorithms are compared and verified,and the advantages of DS-InSAR in deformation measurement practice are demonstrated.This work not only offers insights into current trends and focal points for theoretical research on DS-InSAR but also provides practical cases and guidance for applied research.

OML:an online multi-particle locating method for high-resolution single-event effects studies

Identifying sensitive areas in integrated circuits susceptible to single-event effects(SEE)is crucial for improving radiation hardness.This study presents an online multi-track location(OML)framework to enhance the high-resolution online trajectory detection for the Hi’Beam-SEE system,which aims to localize SEE-sensitive positions on the IC at the micrometer scale and in real time.We employed a reparameterization method to accelerate the inference speed,merging the branches of the backbone of the location in the deployment scenario.Additionally,we designed an irregular convolution kernel,an attention mechanism,and a fused loss function to improve the positioning accuracy.OML demonstrates exceptional realtime processing capabilities,achieving a positioning accuracy of 1.83μm in processing data generated by the Hi’Beam-SEE system at 163 frames per second per GPU.

Double quantum images encryption scheme based on chaotic system

This paper explores a double quantum images representation(DNEQR)model that allows for simultaneous storage of two digital images in a quantum superposition state.Additionally,a new type of two-dimensional hyperchaotic system based on sine and logistic maps is investigated,offering a wider parameter space and better chaotic behavior compared to the sine and logistic maps.Based on the DNEQR model and the hyperchaotic system,a double quantum images encryption algorithm is proposed.Firstly,two classical plaintext images are transformed into quantum states using the DNEQR model.Then,the proposed hyperchaotic system is employed to iteratively generate pseudo-random sequences.These chaotic sequences are utilized to perform pixel value and position operations on the quantum image,resulting in changes to both pixel values and positions.Finally,the ciphertext image can be obtained by qubit-level diffusion using two XOR operations between the position-permutated image and the pseudo-random sequences.The corresponding quantum circuits are also given.Experimental results demonstrate that the proposed scheme ensures the security of the images during transmission,improves the encryption efficiency,and enhances anti-interference and anti-attack capabilities.

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance evaluation.When the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and detectors.This study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam energies.Simulations were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope layouts.The simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be ignored.Compared with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

High-Secured Image LSB Steganography Using AVL-Tree with Random RGB Channel Substitution

Random pixel selection is one of the image steganography methods that has achieved significant success in enhancing the robustness of hidden data.This property makes it difficult for steganalysts’powerful data extraction tools to detect the hidden data and ensures high-quality stego image generation.However,using a seed key to generate non-repeated sequential numbers takes a long time because it requires specific mathematical equations.In addition,these numbers may cluster in certain ranges.The hidden data in these clustered pixels will reduce the image quality,which steganalysis tools can detect.Therefore,this paper proposes a data structure that safeguards the steganographic model data and maintains the quality of the stego image.This paper employs the AdelsonVelsky and Landis(AVL)tree data structure algorithm to implement the randomization pixel selection technique for data concealment.The AVL tree algorithm provides several advantages for image steganography.Firstly,it ensures balanced tree structures,which leads to efficient data retrieval and insertion operations.Secondly,the self-balancing nature of AVL trees minimizes clustering by maintaining an even distribution of pixels,thereby preserving the stego image quality.The data structure employs the pixel indicator technique for Red,Green,and Blue(RGB)channel extraction.The green channel serves as the foundation for building a balanced binary tree.First,the sender identifies the colored cover image and secret data.The sender will use the two least significant bits(2-LSB)of RGB channels to conceal the data’s size and associated information.The next step is to create a balanced binary tree based on the green channel.Utilizing the channel pixel indicator on the LSB of the green channel,we can conceal bits in the 2-LSB of the red or blue channel.The first four levels of the data structure tree will mask the data size,while subsequent levels will conceal the remaining digits of secret data.After embedding the bits in the binary tree level by level,the model restores the AVL tree to create the stego image.Ultimately,the receiver receives this stego image through the public channel,enabling secret data recovery without stego or crypto keys.This method ensures that the stego image appears unsuspicious to potential attackers.Without an extraction algorithm,a third party cannot extract the original secret information from an intercepted stego image.Experimental results showed high levels of imperceptibility and security.

Image encryption algorithm based on multiple chaotic systems and improved Joseph block scrambling

With the rapid development of digital information technology,images are increasingly used in various fields.To ensure the security of image data,prevent unauthorized tampering and leakage,maintain personal privacy,and protect intellectual property rights,this study proposes an innovative color image encryption algorithm.Initially,the Mersenne Twister algorithm is utilized to generate high-quality pseudo-random numbers,establishing a robust basis for subsequent operations.Subsequently,two distinct chaotic systems,the autonomous non-Hamiltonian chaotic system and the tentlogistic-cosine chaotic mapping,are employed to produce chaotic random sequences.These chaotic sequences are used to control the encoding and decoding process of the DNA,effectively scrambling the image pixels.Furthermore,the complexity of the encryption process is enhanced through improved Joseph block scrambling.Thorough experimental verification,research,and analysis,the average value of the information entropy test data reaches as high as 7.999.Additionally,the average value of the number of pixels change rate(NPCR)test data is 99.6101%,which closely approaches the ideal value of 99.6094%.This algorithm not only guarantees image quality but also substantially raises the difficulty of decryption.

西安电子科技大学陈晓峰团队研究成果被USENIX Security收录

近日,第33届USENIX Security Symposium (USENIX Security 2024)在美国费城召开。西安电子科技大学网络与信息安全学院陈晓峰教授团队的最新研究成果“Pixel+and Pixel++:Compact and Efficient Forward-Secure Multi-Signatures for Po S Blockchain Consensus”被大会全文录用。该研究成果由西安电子科技大学、南开大学和伍伦贡大学(University of Wollongong)合作完成,第一作者为陈晓峰教授合作指导的博士后魏江宏。

Curative observation and the influence on the mental status of the patients with acne scars treated with pixe12940 laser

目的：了解痤疮凹陷性瘢痕患者的心理健康状况，观察Pixel 2940激光治疗痤疮凹陷性瘢痕的疗效及对患者心理健康的影响。方法：2010年10月～2012年8月，笔者科室采用Pixel 2940激光治疗痤疮瘢痕患者39例，并在治疗前和治疗结束后1月用Cardiff痤疮心理评估量表评估患者心理状况。结果：Pixel 2940激光治疗痤疮凹陷性瘢痕有效率达94．9％，副反应少而轻；痤疮影响了患者的心理健康，患者常常感到焦虑、愤怒和自信心下降等，但治疗后心理明显好转。结论：用Pixel 2940激光治疗痤疮凹陷性瘢痕疗效稳定、副反应少，可改善患者心理健康状况。

Pixel激光治疗面部痤疮瘢痕

目的:观察Pixel激光治疗面部痤疮瘢痕的临床效果。方法:采用以色列飞顿2940nm像素激光对54例痤疮瘢痕的患者进行治疗,共治疗3～5次,每次间隔时间2～3周。除少数对疼痛敏感的患者治疗前外涂表面麻醉,其余不用任何处理。对比治疗前后的照片并进行疗效评价。结果:共治疗54例痤疮瘢痕患者,有效率75%～100%。Pixel同时可以有效改善4种不同类型痤疮,无一例色沉和瘢痕。结论:Pixel激光治疗痤疮凹陷性瘢痕疗效满意,对增生瘢痕疗效有限。是一种适合东方人痤疮瘢痕的安全,有效的治疗方法。

Design,Analysis,and Optimization of a CMOS Active Pixel Sensor

A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and success-fully taped out with a Chartered 0.35μm process. The pixel pitch is 8μm × 8μm with a fill factor of 57%, the photo-sensitivity is 0.8V/（lux · s） ,and the dynamic range is 50dB. Theoretical analysis and test results indicate that as the process is scaled down, a smaller pixel pitch reduces the sensitivity. A deep junction n-well/p-substrate photodiode with a reasonable fill factor and high sensitivity are more appropriate for submicron processes.

基于Pipeline体系结构的三维PACS图像终端系统

提出了一种基于Ｐｉｐｅｌｉｎｅ体系结构的图像渲染系统，用于医学图像的处理与绘制。相比于传统的分为体绘制和面绘制的计算机图形学算法，该体系结构能有效的将诸多图形与图像处理方法综合在一起，并且明确的将这些方法与Ｖｅｒｔｅｘ Ｂｕｆｆｅｒ、Ｐｉｘｅｌ Ｂｕｆｆｅｒ和Ｔｅｘｔｕｒｅ Ｂｕｆｆｅｒ相链接起来，并入Ｐｉｐｅｌｉｎｅ体系结构。在该体系结构上，实现了三维组织提取显示（ＳＳＤ显示方式）、最大密度投影显示（ＭＩＰ）、数字重建图像（ＤＲＲ）、三维空间断层显示（ＭＰＲ）、三维空间曲面切割（ＣＰＲ）和交互式虚拟内窥镜（ｉＶＥ）等多种功能，并将其应用在所开发的三维ＰＡＣＳ图像终端系统上。

基于ADV212的数字域TDI图像压缩设计

针对星上高清灰度图像存储压力过大的问题,提出了基于ADV212图像压缩芯片结合FPGA实现的数字域TDI积分图像压缩解决方案。在实现的过程中ADV212芯片是以16Bit-Raw Pixel-JDATA模式完成对图像进行高效高质压缩,图像以8Bit-RAW格式从Basler CMOS传感器相机中输入,使用FPGA完成对8Bit-RAW格式图像的数字域TDI积分算法实现、ADV212芯片的配置及驱动、ADV212芯片VDATA路输入图像的预处理及整个系统的控制。实验表明在无损压缩情况下,系统可以稳定工作在50 MHz像素时钟下,压缩比可达2∶1。该系统具备轻小、使用灵活、图像存储率高及压缩率可调等优点。

Pixel激光治疗黄褐斑的疗效和安全性分析

目的:评估Pixel激光治疗黄褐斑的疗效及安全性。方法:采用Pixel激光治疗黄褐斑患者72例,3～4周治疗1次,3～5次为一个疗程,每次复诊由医生和患者共同评定疗效和安全性。结果:72例患者中,痊愈17例(23.61%),显效18例(25.0%),有效率48.61%。轻度组:痊愈率45.45%(15例),显效率36.36%(12例),有效率81.81%;重度组:痊愈率5.13%(2例),显效率15.38%(6例),有效率20.51%;两组比较有显著性差异。病程小于2年者,有效率68.42%,疗效高于病程大于2年者。21例患者术后出现轻度色素沉着,均于术后3个月消退。结论:Pixel激光治疗黄褐斑安全有效,病程短、颜色浅者疗效更佳。

无人机航空摄影测量在地形图测绘中的应用

航空数字摄影测量是基础地理信息采集的最有效手段之一。随着计算机技术的发展和微处理机的广泛应用,政府各部门对测绘资料的需求越来越大,对资料现势性要求越来越高,对资料所能包涵的信息容量越来越多。无人机航空摄影测量作为一种新型的测量方式不断呈现在大家的面前,发展低空无人飞行器航测遥感系统是提高测绘现势性的迫切需要,是做好应急救急工作的迫切需要,是构建数字中国、数字城市建设的迫切需要。低空无人飞行器航测遥感系统推动了地理信息获取向全天候、全天时、实时化迈进的步伐,无人机航测遥感系统具有机动灵活、成本低、载荷多样性、用途广泛、操作简单等优点,在现代测绘行业中发挥着越来越重要的作用。本文针对我单位承接的市场项目1∶2 000带状地形图测绘,结合实际生产和技术改造,通过一定范围内的实践,与大家一起探讨无人机航测遥感技术的特点及对影像畸变改正、全自动空三解算、立体测图等无人机航空摄影测量生产工序中的关键技术。

基于软硬属性转换的遥感图像亚像元定位算法

混合像元普通存在于遥感图像之中,给遥感数据的解译带来了较大挑战。近些年发展起来的混合像元分解技术能估计混合像元内各类地物的混合比例,却不能估计各类地物的具体分布。亚像元定位（sub-pixel mapping,SPM）正是在此问题基础上发展起来的一种新型技术。SPM将原始混合像元分割成多个亚像元并估计各亚像元的地物类别,其本质上是一种更高空间分辨率下的硬分类技术。

Pixel Factory影像数据处理系统介绍与应用探讨

简单阐述Pixel Factory体系结构及其特点,结合航空、航天遥感影像数据处理项目重点分析该系统在海量遥感影像数据处理中所展现出的优势并针对存在的相关问题进行探讨。实践证明,该系统在传统正射影像制作、海量卫星影像数据处理方面具有明显算法优势,但DSM自动计算算法及框幅式航摄数据空中三角测量功能仍需增强。

基于Pixel Factory的ADS80影像快速处理方法

Pixel Factory系统是目前国内外最高端的影像快速处理系统,ADS80数码相机是目前主流的航空摄影测量系统,两套系统在各自的领域均具有其它系统无可比拟的优势。本文基于Pixel Factory影像快速处理系统,提供ADS80影像的处理方法,并用实际的生产数据进行试验。试验结果表明:利用Pixel Factory影像快速处理系统处理ADS80数码影像,可以大大减少外业控制,自动、快速、高效地获取高精度数字正射影像。

Pixel Facory框幅影像加密成果在DLG生产中的应用探讨

Pixel Factory利用POS数据,可减少对外业控制点的需求数量,实现高精度快速空三。但是目前,Pixel Factory的框幅影像加密成果,无法直接用于立体定向及数字线划图DLG数据的生产。本文利用Pixel Factory影像快速处理系统与IMU/GPS辅助的航空数码影像,提供Pixel Factory框幅影像加密成果在DLG生产中的应用方法,并用实际的生产数据进行试验,通过对数据的处理及精度检测,验证了本论文方法的可行性与实用性。