ABSTRACT. The Competitive Influence Maximization (CIM) problem has been extensively studied in recent years due to its importance in Viral Marketing. Basically, CIM problem requires finding out a set of seed users to diffuse information such that the number of affected nodes could be maximized in a competitive context where other competitors are also performing information broadcasting activities. Recent works focus on uncertainty models (probabilistic models) to address this problem at the cost of difficulty which is \#P-hard in estimating objective functions, thus those algorithms are time consuming even in the case of small or medium size networks. In reality, with the support of data mining techniques, we are able to build deterministic information spreading models. In this work, we propose a new approach to the CIM problem based on such a deterministic information spreading model. Our approach shows that the complexity in estimating objective functions is $O(n^2)$ and it also proposes 2 effective algorithms to address CIM problem. Experiment results on 4 benchmark datasets Email-EU, Gnutella-1, Gnutella-2, and Epinion show that our algorithms outperform other algorithms, especially in term of running time on medium size networks.

ABSTRACT. As Web traffics is increasing on the Internet, caching solutions for Web systems are becoming more important since they can greatly expand system scalability.At the core of the cache server operation is the replacement algorithm, which is responsible for selecting, according to a cache replacement policy, the cached pages that should be removed in order to make space for new pages. Traditional replacement policies used in practice take advantage of temporal reference locality by removing the least recently/frequently requested pages from the cache. Lately, due to the properties of semantic content in of web pages, there are some new attempts to implement cache replacement based on multiple parameters including semantic content. This paper presents a semantic-aware caching policy enhanced with the use of function-based cache values. Our simulations show that out enhancements outperform traditional methods in terms of hit rate, which can be useful for website with many small and equal-size web objects.

ABSTRACT. We have been investigating methods for establishing an effective, immediate defense mechanism against the DDoS attacks on Web applications via hacker botnets, in which this defense mechanism can be immediately active without preparation time, e.g. for training data, usually asked for in existing proposals. In this study, we propose a new mechanism, including new data structures and algorithms, that allow the detection and filtering of large amounts of attack packets (Web request) based on monitoring and capturing the suspect groups of source IPs that can be sending packets at similar patterns, i.e. with very high and similar frequencies. The proposed algorithm places great emphasis on reducing storage space and processing time so it is promising to be effective in real-time attack response.

ABSTRACT. In IoT-based system, over-the-air (OTA) programming or IoTs reconfiguration plays a vital role, especially in large-scale deployments. OTA programming allows IoTs devices to be replaced and upgraded the running applications or image by the newer versions without effort on manually install one by one device. However, the development of OTA programming also meets many challenges due to the limitations of memory resources, battery energy as well as communication support of small and constraint devices. Therefore, designing OTA programming solutions supported by a strong security mechanism has been still an open issue. In this paper, an integration of AES cryptography into a well-known network programming protocol (Deluge on TinyOS 2.x) is presented. The paper not only explains Deluge protocol’s operation, messages format but also provides numerical results when running this enhancement with real IoTs devices (Telosb mote on TinyOS 2.x). The developed solution can be deployed in the real IoT-based systems for securely re-configuring IoT devices and the presented empirical results can be used as a dataset for research community to compare in other environments

ABSTRACT. Scheduling is an operation that has a significant impact on the data forwarding performance of OBS nodes. In the case of service differentiation, the scheduling operation is also subject to additional controls from service differentiation supporting mechanisms in which an arriving burst can be admitted to be scheduled depending on its priority level and the availability of wavelengths. There are several proposed scheduling admission control models, but it is hypothesized that the traffic of arriving bursts is stable; the admission control is then performed, basing on the amount of allocated wavelengths and the idle state of these wavelengths. However, arriving burst traffics in OBS networks usually fluctuate and accurate traffic forecasting will help allocate wavelengths more efficiently, increasing the scheduling efficiency in term of increasing bandwidth utilization and reducing burst loss. This paper proposes a model of traffic prediction based admission control, which includes a statistical method of forecasting the arriving rate of bursts for flexible wavelength allocation and a mechanism of prioritizing more resources for high-priority bursts. A Markov chain based analysis model is also constructed to validate the proposed model and compare to simulation results.

ABSTRACT. The Advanced Encryption Standard (AES) algorithm is the best choice for security services in many applications. This paper presents an AES hardware using composite-field by decomposing the complex GF(28) to the lower order field. Conventional designs are based on the Lookup table Sbox (LUTSbox)[1] to implement the S-box and InvS-box that cost much memory and area. Our proposed design using combinational logic is based on composite-field in finite fields GF(28). The area cost is reduced because most of the functionalities are shared for both S-box and InvS-box, they are implemented on the same hardware. The proposed implementation occupies 4.1 kGEs and the maximum frequency is 180 MHz. Our implementation uses Verilog HDL on Virtex7 FPGA board.

ABSTRACT. The Clock Constraint Specification Language (CCSL) offers constructs for expressing chronological and causal relations on events of an embedded system. CCSL simulator, TimeSquare allows one to visualize executions of the specified systems by determining step by step sets of synchronously occurring events.

When several different sets of events are possible at a given step, the simulator uses a global simulation policy to choose one. However, this mechanism does not consider any priority between events.

Inspired by priority in Petri nets, we show how to formally define a priority system supporting possibly synchronous partial orders of events. Both formal definitions and an efficient implementation are presented.

ABSTRACT. There were many online judge systems which were created to automatically judge programming code. Among the development of online judge systems, the open-source online judge systems are also developing gradually, like for example Sharif Online Judge and DOMjudge. This research modified the DOMjudge by creating additional functions and improved the graphic user interface of DOMjudge in the user-friendly way to students and teachers. Besides, the research also developed a plagiarism detection system, which helps teachers to find out who cheated during the contest. This paper showed that proposed preprocessing and using k-Grams, Hashing and Suffix Array to compare two source codes is better than conventional methods.

ABSTRACT. Testing plays a crucial role in software development for ensuring quality. Mutation testing in general and higher order mutation in particular are the good techniques to evaluate the quality of test data, i.e. determining if test data can uncover errors. However, higher order mutation is often very costly because of huge number of generated mutants. In this work, we focus on reducing the cost of higher order mutation testing. We propose different strategies to combine first order mutants to generate less number of higher order mutants for a program under test, but keep the quality of generated mutants. The proposed strategies are experimented on a set of different programs and the results show the effectiveness in terms of number generated mutants and mutation score.

ABSTRACT. In this short note, we are concerned with the fairness condition "A and B hold almost equally often", which is important for specifying and verifying the correctness of non-terminating processes and protocols. We introduce the logic of temporal domination, in which the above condition can be expressed. We present syntax and semantics of our logic and show that it is a proper extension of linear time temporal logic. In order to obtain this result, we rely on the corresponding result for k-counting automata.

ABSTRACT. Dynamic adaptation of software is the change in the structure or behavior of the software at runtime without stopping whole system. In component-based adaptive software, an adaptation process includes actions such as stopping and removing components, adding and starting component, etc. A challenge when realizing the adaptation process is to ensure the system consistency. One of the system consistency aspects, the state of the system must be guaranteed. The maintenance of state is a challenge when reconfiguring the system, specially the inhomogeneity of system versions before and after adaptation. To cope with this challenge, some approaches use state transfer functions which are manually implemented to realize the state transfer. However, they are ad-hoc approaches. They do not offer a general solution to transfer state in the adaptive system which can be applied from design time to runtime in the development process. Therefore, we propose an approach based on a state transfer model that is specified at design time and used at runtime during adaptation process for transferring state.

ABSTRACT. The evidence of effectiveness of Cognitive Behavioral Therapy (CBT) based mental health applications is shown to be equivalent with face-to-face CBT. Although there is a high number of users, the adherence of users to the intervention is low. Meanwhile, user non-adherence could happen on purpose. However, the reasons for this circumstance are not well examined, particularly from a user’s perspective. The question of which features engage them to use as well as to continue using these interventions are not well understood. From the designer’s perspective, to answer this question, it is essential to understand the context of app uses, particularly, three precedent questions: who are intended users, what they use it for, and why they use it need to be examined. This study answers these three questions by analyzing user reviews of several sample mental health applications which the core design is primarily based on a CBT. The qualitative analysis indicates that most of reviews are from people with common MH problems. Some people simply use the app to relax, track their mood, practice mindfulness, self-care, or build healthy habits. The majority of users have used the apps as complementary to the professional-based treatment. Users use the app because it makes them more positive, happy, self-conscious, calm, fun, focused, relaxed, motivated, mindful, self-controlled or better at sleep. Importantly, they highly appreciate the ability to figure out what going on their health, to help them keep on progress of health, to see correlation between causes and effects of their health problems, to conduct self-evaluation and self-reflection, to learn good things, to build good habits, and to provoke, reframe, and organize their thoughts. These findings will help the designers think of appropriate approaches to design the app which helps users better at achieving their targets.

ABSTRACT. In this article, a CPW-fed flexible antenna which can work at two separate operating frequencies is proposed. The split ring resonator structure is used to replace the conventional monopole patch in order to generate two resonant frequencies. The antenna is aimed to fabricate with a round shape on a flexible material, a paper substrate with ε = 3.55 to make it suitable for wearing on the chest of the patient for monitoring device. The result shows that the antenna radiates at 2.45 and 5.5 GHz that can be connect with WiFi and Wireless Local Area Network (WLAN) network for remote monitoring.

ABSTRACT. In Massive MIMO’s uplink, the signal detection algorithms such as minimum mean square error (MMSE), zero-forcing (ZF) achieve nearly optimal result, but they use inverse matrix in design, the complexity in calculation is very large. In this paper, we propose an efficient algorithm based on the SOR (Successive over Relaxation) algorithm with the better performance than the conventional SOR-based algorithm. The obtained result shows that the performance of the efficient SOR-based algorithm is better than the conventional SOR-based algorithm and close to MMSE algorithm. Besides, we propose the hardware architecture for the proposed SOR-based algorithm.

ABSTRACT. Internet of Things (IoTs) applications normally demand n-tier distributed architecture with numerous diverse components, e.g., sensors attached over IoTs end devices in the front-end, and the web application servers, database servers in the back-end. To deal with the dynamic changes and unpredicted events in the environments, the reconfiguration and re-programming of IoTs applications on IoTs end devices is of vital importance. This issue is also called over-the-air-programming (OTAP) of IoTs applications remotely through wireless IoTs network protocols. In this paper, we propose an IoTs reconfiguration framework, namely RFL-IoT, for the reconfiguration of IoTs applications upon the changes of the context and derived by the fuzzy logic for the smart context management. To validate our proposed framework, experiments have been carried out in the smart Air Conditioner application by updating new firmware to IoTs end devices to change the behaviors of the IoTs application upon the reported temperature. Results show that our proposed framework is suitable for the dynamic reconfiguration of IoTs applications, at a reasonable cost in terms of energy consumption and time for complete reconfiguration process

ABSTRACT. We revisit the well-known research topic of landmark-based compact routing in order to support designing interconnection topologies that can meet new demanding requirements and issues brought up by advances in areas such as massively parallel computing or large-scale data centers. Particularly, it is necessary to reduce the routing table size (RTS) as much as possible while maintaining other performance factors in a good state. Based on a new landmark selection technique, we propose our Geographic Landmark-based Compact Routing scheme which can reduce the RTS from the well-known Thorup and Zwick's scheme by roughly 15% for a network of 1024 nodes and roughly 45% for a network of at least 100K nodes, and which also produces shorter average path length.

ABSTRACT. Mental illnesses are a major cause of disease burden in all countries around the world. Among the available treatments, Cognitive Behavioral Therapy (CBT) based mental health applications (apps) have been introduced as promising in helping people deal with common mental illnesses by themselves. However, the theoretical underpinnings for technological approaches used to design these interventions have not been clarified. Based on the literature and its relevance to CBT, theories of Persuasive Technology could be potentially used as a suitable approach to design. However, an embrace of persuasive technology has not been widely studied, particularly from the user’s perspectives. Therefore, this study has evaluated and explored the user’s perception on the persuasiveness of mental health apps by conducting a qualitative analysis of user reviews. The findings of this study will contribute to the designers in developing highly persuasive mental health apps. The results indicated that where the principles of the persuasive systems design (PSD) model were integrated into the design, users expressed satisfaction with the design.

ABSTRACT. Hemodialysis machines are essential in improving life quality of patients with chronic kidney disease and improving hospital outcome in case of acute kidney injury. Maintaining and regulating patient fluid balance is a crucial problem amongst other control problems. Although, the fluid balance control is solved in these machines, there is no documented evidence of solutions, which targets the fluid balance of the patient directly on systemic level. This paper describes a systemic control method with MIMO ANFIS control, where the main target is to provide strict control of peristaltic pumps while the control algorithm fulfills not only pump related requirement but also satisfies the highest fluid balance related expectations. During the research, the practical applicability was being kept in focus.

ABSTRACT. Knowledge visualization tools contribute to the efficiency of the processes implemented for the transfer of knowledge. They provide users with intelligible content representations and facilitate access to knowledge by providing dynamic interaction modes. In this paper we present the tool MCVGraphViz dedicated to the visualization of graphs of interactions between risk factors in the field of cardiovascular diseases. It offers the user an interface to access progressively and dynamically the contents of the graph. MCVGraphViz allows to collect and memorize the actions performed by the user during his navigation in the graph as traces expressed by a path between a starting node and a destination node.