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Side-channel analysis attacks based on deep learning network

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Frontiers of Computer Science 2022年第2期16卷 35-45页

作者： Yu ou Lang LI Hunan Provincial Key Laboratory of Intelligent Information Processing and Application Hengyang Normal UniversityHengyang 421002China College of Information Science and Engineering Hunan Normal UniversityChangsha 410081China College of Computer Science and Technology Hengyang Normal UniversityHengyang 421002China

There has been a growing interest in the sidechannel analysis(SCA)field based on deep learning(DL)*** DL network or model has been developed to improve the efficiency of ***,few studies have investigated the impact of the different models on attack results and the exact relationship between power consumption traces and intermediate *** on the convolutional neural network and the autoencoder,this paper proposes a Template Analysis Pre-trained DL Classification model named TAPDC which contains three *** TAPDC model detects the periodicity of power trace,relating power to the intermediate values and mining the deeper features by the multi-layer convolutional *** implement the TAPDC model and compare it with two classical models in a fair *** evaluative results show that the TAPDC model with autoencoder and deep convolution feature extraction structure in SCA can more effectively extract information from power consumption ***,Using the classifier layer,this model links power information to the probability of intermediate *** completes the conversion from power trace to intermediate values and greatly improves the efficiency of the power attack.

关键词： side-channel analysis template attack machine learning deep learning

Colorectal cancer screening: An updated review of the available options

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World Journal of Gastroenterology 2017年第28期23卷 5086-5096页

作者： Iyad A issa Malak Noureddine Department of Gastroenterology and Hepatology Rafik Hariri University Hospital

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. Nevertheless, in some parts of the world, CRC incidence and mortality remain on the rise, likely due to factors including “westernized” diet, lifestyle, and lack of health-care infrastructure and resources. Participation and adherence to different national screening programs remain obstacles limiting the achievement of screening goals. Different modalities are available ranging from stool based tests to radiology and endoscopy with varying sensitivity and specificity. However, the availability of these tests is limited to areas with high economic resources. Recently, FDA approved a blood-based test (Epi procolon®) for CRC screening. This blood based test may serve to increase the participation and adherence rates. Hence, leading to increase in colon cancer detection and prevention. This article will discuss various CRC screening tests with a particular focus on the data regarding the new approved blood test. Finally, we will propose an algorithm for a simple cost-effective CRC screening program.

关键词： Colorectal cancer Colonoscopy Occult blood Fecal DNA test Blood DNA test Screening Guidelines

Chylous ascites secondary to hyperlipidemic pancreatitis with normal serum amylase and lipase

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World Journal of Gastroenterology 2007年第3期13卷 480-482页

作者： Fahmi Yousef Khan issa Matar Department of Medicine Hamad Medical Corporation Doha Qatar

A 54-year old man with a family history of hyperlipidemia was admitted with a 12 h history of severe generalized abdominal pain associated with nausea, vomiting and abdominal distension. Examination of the abdomen revealed tenderness in the periumblical area with shifting dullness. Serum pancreatic amylase was 29 IU/L and lipase 44 IU/L, triglyceride 36.28 mmol/L. Ultrasound showed ascites. CT of the abdomen with contrast showed inflammatory changes surrounding the pancreas consistent with acute pancreatitis. Ultrasound (US) guided abdomen paracentesis yielded a milky fluid with high triglyceride content consistent with chylous ascites. The patient was kept fasting and intravenous fluid hydration was provided. Meperidine was administered for pain relief. On the following days the patient’s condition improved and he was gradually restarted on a low-fat diet, and fat lowering agent (gemfibrozil) was begun, 600 mg twice a day. On d 14, abdomen US was repeated and showed fluid free peritoneal cavity. The patient was discharged after 18 d of hospitalization with 600 mg gemfibrozil twice a day. At the time of discharge, the fasting triglyceride was 4.2 mmol/L. After four weeks the patient was seen in the clinic, he was well.

关键词： Amylase Chylous ascites Hyperlipidemic pancreatitis

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面向自动语音识别系统的对抗样本生成方法

计算机科学与探索 2025年第1期19卷 253-263页

作者：于振华苏玉璠叶鸥丛旭亚西安科技大学计算机科学与技术学院西安710054

通过对系统进行对抗攻击可以检测系统漏洞,进而提高系统鲁棒性。然而,对抗攻击前往往需要系统的参数信息,这使得攻击条件受限。为此,结合一种新的量子粒子群优化算法,提出一种黑盒有目标对抗攻击方法。该方法通过在原始样本中添加微小噪... 详细信息

通过对系统进行对抗攻击可以检测系统漏洞,进而提高系统鲁棒性。然而,对抗攻击前往往需要系统的参数信息,这使得攻击条件受限。为此,结合一种新的量子粒子群优化算法,提出一种黑盒有目标对抗攻击方法。该方法通过在原始样本中添加微小噪声,构造差异化粒子群,作为初始对抗样本种群;基于记忆搜索的领域重分布策略得到当前种群的全局最优粒子,从而生成初始对抗样本;融入扩维和自适应权重位置更新,使得种群更接近目标;根据对抗样本与目标语句的编辑距离,继续优化初始对抗样本,生成最终对抗样本。为了验证方法的攻击效果,在GoogleSpeech、LibriSpeech以及CommonVoice数据集上,对语音识别模型DeepSpeech进行实验,将目标语句设置为不同场景中的常见语音指令。实验结果表明,提出的方法在三个数据集上成功率都优于对比方法,其中在Common Voice数据集上的成功率比对比方法提升了10个百分点。同时,召集志愿者对生成的对抗样本噪声强度进行主观评估,其中82.4%的对抗样本被志愿者判断为没有噪声或噪声很小。

关键词：对抗攻击语音识别黑盒攻击样本生成量子粒子群算法梯度评估方法

Design approaches for active,semi-active and passive control systems based on analysis of characteristics of active control force

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 493-506页

作者： ou Jinping Li Hui School of Civil ＆ Hydraulic Engineering Dalian University of Technology Dalian 116024 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 China

In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed：（1） active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; （2） the linear quadratic regulator （LQR）-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and （3） the active control forces prevent mction most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the perfonrlance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called ＂design principle＂. The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the c

关键词： active control: semi-active control smart control damping design approach

Evaluation and modification of some empirical and semi-empirical approaches for prediction of area-storage capacity curves in reservoirs of dams

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International Journal of Sediment Research 2017年第1期32卷 127-135页

作者： issa E.issa Nadhir Al-Ansari Govand Sherwany Sven Knutsson Department of Civil Environmental and Natural Resources EngineeringLulea University of Technology Department of Dams and Water Resources Engineering University of Mosul

The storage capacity of reservoirs is gradually reduced due to sediment accumulation that causes changes in the area-storage capacity（ASC） *** these curves and predicting their future change is an important issue for planners,designers and operators of *** empirical and semiempirical approaches have been suggested for establishing and predicting the future changes for these *** this study four empirical and semi-empirical methods were evaluated and three of them were modified to be used for the prediction of changes in the ASC curves due to sedimentation,based on the existing sedimentation survey data for 11 reservoirs in the *** evaluation,these approaches were reviewed and used to determine sedimentation depth and establishing the ASC curves for the Mosul dam reservoir（MDR）,which is the biggest hydraulic structure on the River Tigris in northern *** started operating in 1986 with a storage capacity of 11.11 km;and a water surface area 380 km2 at normal operation stage（330 m a.s.l.）.The results obtained from these methods were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the *** evaluation results showed three methods had presented more accurate results for estimating water depth or sedimentation depth at dam site with percentage error about 1.06-3.30%.Whilst for establishing ASC curves,one method presented good agreement result with survey ***,ASC and sedimentation depths at dam site of MDR for periods 50,75,100 and 125 years were estimated using the modified approaches and the area reduction *** results of the modified methods provided reasonable agreement when compared with the area reduction method proposed by the *** of Reclamation and the agreement became better with an increase in time period.

关键词： Area-capacity curves Reservoir sedimentation Area reduction method Mosul dam

DFT calculation analysis of oxygen reduction activity and stability of bimetallic catalysts with Pt-segregated surface

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Science China Chemistry 2015年第4期58卷 586-592页

作者： Lihui ou Shengli Chen College of Chemistry and Molecular Sciences Wuhan University College of Chemistry and Chemical Engineering Hunan University of Arts and Science

The stability and oxygen reduction reaction （ORR） activity of the Pt-segregated surface in various Pt-M alloys （M： transition metals） are investigated through systematic DFT calculations on the thermodynamic （alloy formation energy and Pt surface segregation energy）, surface chemical property （oxygen binding energy） and electronic （d-band center） properties. Factors af- fecting these properties, such as the atomic radii and surface energy of M and the electronic ligand interaction between Pt and M are analyzed as a function of outmost d electron numbers of M. It is shown that the electronic ligand interaction plays de- termining role in the alloy formation energy of various Pt-M alloys; the formation of Pt-segregated surface in Pt-M alloys is faw）red when alloying metals have higher surface energy and smaller radii than Pt; the oxygen binding energy on the Pt-segregated surface in Pt-M alloys varies approximately linearly with the d-band center of surface Pt atoms; the lattice strain and electronic ligand effects are simply additive in Pt-M alloys; the stain effect in Pt-M alloys nearly linearly affects the d-band center of the Pt-segregated surface in Pt-M alloys; transition metals with less than 10 d electrons mostly exhibit electron ligand effects which result in downshift of the d-band center of the segregated surface Pt atoms, while those with ten d electrons exhibit electron ligand effect upshifting the d-band center of the segregated Pt atoms.

关键词： oxygen reduction reaction bimetallic catalysts Pt-segregated surface DFT calculation

Effects of aspect ratio on shock-cylinder interaction

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Acta Mechanica Sinica 2019年第1期35卷 61-69,I0003页

作者： Junfeng ou Zhigang Zhai Department of Modem Mechanics University of Science and Technology of ChinaHefei 230026China

Interaction of a planar shock wave with a discontinuous SF& elliptic gas cylinder surrounded by air is investigated. Special attention is given to the effects of aspect ratio on wave pattern, interface evolution, and material mixing. An ideal discontinuous two-dimensional gas cylinder is created by the soap film technique in experiments, and the shocked flow is captured by schlieren photography combined with a high-speed video camera. The surface of the gas cylinder is clear enough to observe the shock motions, and the distinct interface boundaries allow us to extract more details. As aspect ratio varies, the shock focusing process is quite different. For the prolate gas cylinder, an inward jet is produced although an internal shock focusing firstly occurs. The inward jet has never been observed in membraneless prolate ellipse experiments probably because the inward jet is so faint due to less vorticity generation on membraneless interface that it is difficult to be observed. For the oblate gas cylinder, a secondary vortex pair, which has not been described clearly in previous work, is derived from the downstream interface. The material lines at early stages are extracted from experiments, which grow faster as aspect ratio increases. The in terfacial area, the mean volume fraction and the mixing rate are presented from computations, and the results show that the increase of aspect ratio promotes the mixing between gases.

关键词： Shock-cylinder interaction Jet Aspect ratio

The effects of the rotor-stator interaction on unsteady pressure pulsation and radial force in a centrifugal pump

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Journal of Hydrodynamics 2018年第4期30卷 672-681页

作者： issa Chalghoum Sami Elaoud Hatem Kanfoudi Mohsen Akrout Research Laboratory "Applied Fluid Mechanics Process and Environment Engineering" National Engineering School of Sfax Sfax Tunisia Research Laboratory "Laboratory of Hydraulics and Environment Modeling" National Engineering School of Tunis ENIT Hydraulic Engineering Tunis Tunisia

An unsteady numerical analysis has been conducted to study the strong interaction between impeller blade and volute tongue of a centrifugal pump. The 3-D-URANS equations were solved with the shear stress transport turbulence model for a wide range of flow rates. These unsteady interactions are mostly related to the unsteady radial force due to an imbalance in the pressure field at the impeller periphery. This force represents dynamic load that are one of the most important sources of vibration and hydraulic noise. Based on this phenomenon, this work analyzes and gives a more realistic prediction of the pressure fluctuation and the radial force during steady and unsteady calculation by considering the effect of the change in the pump operating point. Actually, the pressure fluctuations in the impeller and the volute were recorded by mounting nine monitoring points on the impeller and volute casing. The results of the existing analysis has proven that the pressure fluctuation is periodic due to the relative position of impeller blade to volute tongue. The characteristics of the time domain and frequency domain of the pressure pulsation were analyzed under different coupling conditions. Fast Fourier transform was performed to obtain the spectra of pressure pulsation. Besides, the steady and unsteady forces were calculated around the impeller periphery to fully characterize the pump behavior. The obtained pump performance curves were numerically compared with the experimental ones, and the outcome have shown an acceptable agreement between both curves.

关键词： Unsteady simulation blade-tongue interaction unsteady pressure distribution blade-passing frequency