The potential of sampling for dynamic analysis

Antivirus companies, mobile application marketplaces, and the security research community, employ techniques based on dynamic code analysis to detect and analyze mobile malware. In this paper, we present a broad range of anti-analysis techniques that malware can employ to evade dynamic analysis in emulated Android environments. Our detection heuristics span three different categories based on (i) static properties, (ii) dynamic sensor information, and (iii) VM-related intricacies of the Android Emulator. To assess the effectiveness of our techniques, we incorporated them in real malware samples and submitted them to publicly available Android dynamic analysis systems, with alarming results. We found all tools and services to be vulnerable to most of our evasion techniques. Even trivial techniques, such as checking the value of the IMEI, are enough to evade some of the existing dynamic analysis frameworks. We propose possible countermeasures to improve the resistance of current dynamic analysis tools against evasion attempts.

In order to thwart dynamic analysis and bypass protection mechanisms, malware have been using several file formats and evasive techniques. While publicly available dynamic malware analysis systems are one of the main sources of information for researchers, security analysts and incident response professionals, they are unable to cope with all types of threats. Therefore, it is difficult to gather information from public systems about CPL, .NET/Mono, 64-bits, reboot-dependent, or malware targeting systems newer than Windows XP, which result in a lack of understanding about how current malware behave during infections on modern operating systems. In this paper, we discuss the challenges and issues faced during the development of this type of analysis system, mainly due to security features available in NT 6.x kernel versions of Windows OS. We also introduce a dynamic analysis system that addresses the aforementioned types of malware as well as present results obtained from their analyses.

Purpose Under the national strategy of “Building a Strong Maritime Country,” this study aims to scientifically evaluate the high-quality development level of China’s coastal marine economy through quantitative analysis. This study aims to reveal the spatiotemporal evolution law of marine economic efficiency in China’s coastal regions and establish a dynamic assessment system to forecast future development trends. Design/methodology/approach This research develops a marine economic efficiency evaluation system based on the undesirable-output super-SBM model to measure and analyze the efficiency of 11 coastal provinces (excluding Hong Kong, Macao and Taiwan) from 2011 to 2022. Combined with grey prediction models, it forecasts marine economic efficiency trends for 2023–2030. Findings (1) China's marine economic efficiency showed significant regional disparities during 2011–2022, with developed eastern coastal provinces like Shanghai reaching the frontier while others like Liaoning lagged behind. (2) Projections for 2023–2030 indicate an overall 1.58% annual efficiency growth, but innovation-driven regions will outperform traditional resource-dependent areas, highlighting the need for technological transformation. (3) Despite national efficiency improvements, widening regional gaps emphasize the urgency to transition from factor-driven to innovation-driven marine development, particularly for struggling central-western regions. Originality/value As the first study to integrate the super-SBM model with grey prediction techniques, it overcomes the limitations of traditional efficiency research that relies solely on cross-sectional data, offering a novel methodological framework for dynamic time-series analysis. The conclusions provide a basis for coastal provinces to formulate differentiated policies.

Static and dynamic program analysis techniques are important research areas in software security. Static analysis helps us locate vulnerabilities in a software by looking at the source code. Dynamic analysis helps us reason about the behavior of the software from information gathered at run-time. In this thesis, we are focusing on data flow analysis and heap analysis which are key static and dynamic program analysis techniques respectively.
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\nIn the first part of this thesis, we aim at detecting vulnerabilities in Android applications which have capability leaks. The security of the Android platform relies mainly on sandboxing applications and restricting their capabilities such that no application, by default, can perform any operations that would adversely impact other applications, the operating system, or the user. However, a recent research reported that a genuine but vulnerable application may leak its capabilities. When being leveraged, other applications can gain extra capabilities which they are not granted originally. We present DroidChecker, an Android application analyzing tool which searches for the aforementioned vulnerability in Android applications. DroidChecker uses interprocedural control flow graph searching and static taint checking to detect exploitable data paths in an Android application. We analyzed more than 1100 Android applications using DroidChecker and found 6 previously unknown vulnerable applications including the renowned Adobe Photoshop Express application. We also developed a malicious application that exploits the previously unknown vulnerability found in the Adobe Photoshop Express application. We showed that the malicious application, which is not granted any permissions, can access contacts on the phone with just a few lines of code.
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\nIn the second part of this thesis, we explore the use of heap analysis to extract software birthmarks. There are techniques like code obfuscation and watermarking which can make the source code of a program difficult to understand by humans and prove the ownership of the program. However, code obfuscation cannot avoid the source code being copied and a watermark can be defaced. A birthmark is a group of unique characteristics a program possesses that can be used to identify the program. We propose two novel dynamic birthmark systems based on the run-time heap. A dynamic birthmark is one that is extracted when the program is executing. Since it is based on the run-time behavior of the program, semantics-preserving transformations of the code like obfuscation cannot defeat dynamic birthmarks. In this regard, dynamic birthmarks are more robust compared with static birthmarks.
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\nTo the best of our knowledge, these are the first birthmark systems using heap analysis as the underlying technique. The basic idea is to take snapshots of the heap while the program is running. From the snapshots, heap graphs are constructed to model the referencing structure between objects. After going through some filtering and referencing processes, they become the birthmarks. The two birthmark systems have been devised to extract birthmarks for Java programs and JavaScript programs respectively. While the underlying ideas of the two birthmark systems are similar, the differences in nature of the two programming languages led to different implementation designs.

This paper presents a comprehensive dynamical systems analysis of a generalized (3 + 1)-dimensional Davey–Stewartson equation with parabolic law nonlinearity. The complex partial differential equation is reduced to a planar dynamical system, enabling detailed bifurcation analysis, equilibrium point characterization, and complete phase portrait construction across different parameter regimes. External periodic forcing transforms the conservative system into a dissipative one, facilitating chaotic dynamics that are confirmed through Lyapunov exponent computation and sensitivity analysis. The complete Lyapunov spectrum provides quantitative evidence of chaotic behavior. Using the new mapping method and the new Kudryashov method, we obtain novel exact solutions, including bright and dark solitons, rogue waves, kink-shaped structures, and periodic patterns. The derivation of these exact solutions addresses the distinctive challenges posed by parabolic law nonlinearity and establishes crucial connections with phase space structures identified through bifurcation analysis. The interplay between analytical solutions and dynamical systems theory reveals fundamental mechanisms governing wave stability, bifurcations, and chaos in higher-dimensional nonlinear systems, with applications in nonlinear optics and fluid dynamics.

The Dynamic Analysis and Design System software is a set of general purpose computer programs that can be used to model and predict the motion of a variety of real world mechanical systems. Using a set of data that describes the machine to be modeled, DADS builds a mathematical model of the real system that calculates positions, velocities, and accelerations of the various parts of the machine, as well as resultant forces that act in the system. By using such a computer program to analyze a machine, the designer can simulate the behavior of a wide range of alternate designs prior to building and testing prototypes. The DADS program is often used for analysis of existing mechanical systems also.

The hanging net shielding system, employing a suspended cage-type enclosed structure to restrict the high-voltage transmission wire, has seen increasingly widespread application in transmission line crossing construction. However, the lack of a comprehensive dynamic analysis methodology has limited the standardization of its design and usage. In this investigation, a systematical dynamic modeling and analysis procedure of the hanging net shielding system is proposed based on the absolute nodal coordinate formulation (ANCF). The carrier cable, slings and transmission wire are discretized by the ANCF cable element. The spatial flexible beam–beam contact model and the assumption of a single contact area are adopted to perform the contact searching between the transmission wire and the horizontal pulley. The system dynamics analysis equation is assembled and solved by generalized alpha method. A full-scale model is simulated for the transmission wire impact condition and the variation history of the tension in carrier cable and the sling cable are given. The peak value of the tension in carrier cable could be 110 kN, while the largest tension in sling cable is 9 kN. Results could help to ensure construction safety, shorten the design cycle of the protection system and reduce the development cost at the same time.

: A dynamic model of the Polaris Sportsman 500 All-Terrain Vehicle (ATV) was built using Dynamic Analysis and Design System (DADS) version 8.5. Aspects of the model included the front MacPherson struts and rear independent suspension. The model also allowed control over the path and speed of the vehicle using the DADS control elements. The modeling methods discussed here are general in nature and may be applied to other DADS vehicle models of similar systems. This report also provides a usefull reference source to those using this model.

This paper provides a comprehensive analysis of the impact of wind farm integration on the stability of an electrical power system, with a particular focus on the dynamic effects induced by wind power during severe system disturbances. The primary objective is to evaluate how wind power integration influences system behavior, particularly under fault conditions. The research utilized the IEEE 9-bus test system, which consists of three generators and nine buses, as a reference benchmark for the stability analysis. Simulations and modeling were performed using PSAT (Power System Analysis Toolbox), a robust tool for static, dynamic, and control analysis of power systems, integrated with Matlab. The study specifically investigated the effects of a three-phase short circuit, representing a significant system disturbance. The dynamic analysis was structured into three phases: pre-fault, fault, and post-fault, to capture the complete impact on system behavior. The results provided valuable insights into critical electrical and electromechanical variables, shedding light on the role of wind farms in maintaining the stability of the power grid, with particular emphasis on the transmission network's resilience and response to disturbances. This work offers a deeper understanding of the integration of renewable energy sources in enhancing grid stability during extreme events.

Program comprehension is an important activity in software maintenance, as software must be sufficiently understood before it can be properly modified. The study of a program's execution, known as dynamic analysis, has become a common technique in this respect and has received substantial attention from the research community, particularly over the last decade. These efforts have resulted in a large research body of which currently there exists no comprehensive overview. This paper reports on a systematic literature survey aimed at the identification and structuring of research on program comprehension through dynamic analysis. From a research body consisting of 4,795 articles published in 14 relevant venues between July 1999 and June 2008 and the references therein, we have systematically selected 176 articles and characterized them in terms of four main facets: activity, target, method, and evaluation. The resulting overview offers insight in what constitutes the main contributions of the field, supports the task of identifying gaps and opportunities, and has motivated our discussion of several important research directions that merit additional consideration in the near future.

In order to design the perception system of the lower limb wearable rehabilitation robot, this study established the kinematics theoretical model of human lower limb and conducted the kinematics analysis of human body. By using the dynamic attitude analysis system, combined with the human body mark points, the position data of human body mark points in the process of standing up, sitting up, walking, stepping up, and squatting were collected. Combined with the movement mechanism of human lower limbs, the characteristics of human motion state transition are analyzed, and the perceptual algorithm for judging human motion intention is studied, so as to determine the wearer's current posture, standing intention while sitting, walking intention while standing, moving intention, and stopping intention during walking. The results show that the angle of the hip joint changes regularly between 0° and 37° and the angle of the knee joint changes regularly between 0° and 70°during the standing process, which is consistent with the angle change trajectory collected by the dynamic attitude analysis system. The angle trajectories of the hip and knee joints measured by the absolute angle sensor are the same as those obtained by the dynamic attitude analysis system. 1.5 rad and 0.3 rad were selected as reasonable and effective thresholds for determining sitting and standing states.

Malware is one of the biggest security threats on the Internet today and deploying effective defensive solutions requires the rapid analysis of a continuously increasing number of malware samples. With the proliferation of metamorphic malware the analysis is further complicated as the efficacy of signature-based static analysis systems is greatly reduced. While dynamic malware analysis is an effective alternative, the approach faces significant challenges as the ever increasing number of samples requiring analysis places a burden on hardware resources. At the same time modern malware can both detect the monitoring environment and hide in unmonitored corners of the system.In this paper we present DRAKVUF, a novel dynamic malware analysis system designed to address these challenges by building on the latest hardware virtualization extensions and the Xen hypervisor. We present a technique for improving stealth by initiating the execution of malware samples without leaving any trace in the analysis machine. We also present novel techniques to eliminate blind-spots created by kernel-mode rootkits by extending the scope of monitoring to include kernel internal functions, and to monitor file-system accesses through the kernel's heap allocations. With extensive tests performed on recent malware samples we show that DRAKVUF achieves significant improvements in conserving hardware resources while providing a stealthy, in-depth view into the behavior of modern malware.

Dynamic analysis and optimization of flare network system for topside process of offshore plant

Free vibration of the complex cable system − An exact method using symbolic computation

This paper presents application guidelines for a new generic plant controller model that can be used for renewable plant dynamic system analysis that may include the control of static compensators (STATCOMs), static var compensators (SVCs), and/or energy storage devices. The authors originally presented the need for such a model to the Western Electricity Coordinating Council (WECC) and contributed to various stages of the new model development led by WECC. As Independent System Operators (ISOs)/Regional Reliability Organizations (RTOs)/Transmission Service Providers (TSPs) are moving toward acceptance and use of generic models only the authors have for the first time applied this new model for an operating renewable plant. The new model was configured, parameterized, and tuned to control two STATCOMs and multiple switched capacitors/reactors to represent a master/auxiliary control strategy as implemented in the plant. Dynamic simulations show that the configured and parameterized model is performing properly as expected. This tuned model was submitted to the system operator for compliance with the interconnection requirements of the plant. This is the first submission of the new generic model for this type of control for a renewable project. The submitted model is appropriate for dynamic simulations, which are routinely performed by ISOs/RTOs/TSPs in system impact studies or transmission planning studies. This paper provides useful guidelines in applying this new model for similar projects.