Capital Structure, Profitability and Firm’s Value: Evidence from Jordan

The purpose of this study is to empirically examine the effect of capital structure and profitability on firm’s value. The study sample included (41) manufacturing companies Out of a total of (63) companies listed on Amman Stock Exchange (ASE) over the five years period (2014-2018). To test the study hypotheses and to achieve its objectives, data was obtained from (ASE) database and annual reports issued by Jordanian manufacturing public shareholding companies. Thus, capital structure (which have been measured by leverage and debt to equity ratio) and profitability (which have been measured by ROA and ROE) are presented as independent variables, while the firm’s value is articulated as the dependent variable using market value and Tobin’s Q as firm’s value measure. Multiple regression analysis is undertaken to analyse the potential effect of capital structure and profitability on firm’s value.The study reveals different results by using different firm’s value measures. When using the first model (market value) the results found that DER has significant effect on market value and the direction of the relationship is positive, while ROA has significant effect on market value and the direction of the relationship is negative. However, when the second model (Tobin’s Q) used the results found that there is no significant effect between all of the independent variables (capital structure and profitability variables) and Tobin’s Q. Keywords: capital structure, profitability, firm’s value, manufacturing companies, Jordan DOI: 10.7176/RJFA/10-20-07 Publication date:October 31st 201

On the consistency of distributed proofs with hidden subtrees

Previous work has shown that distributed authorization systems that fail to sample a consistent snapshot of the underlying system during policy evaluation are vulnerable to a number of attacks. Unfortuantely, the consistency enforcement solutions presented in previous work were designed for systems in which only CA-certified evidence is used during the decision-making process, all of which is available to the decision-making node at runtime. In this article, we generalize previous results and present light-weight mechanisms through which consistency constraints can be enforced in proof systems in which the full details of a proof may be unavailable to the querier due to information release policies, and the existence of certificate authorities for certifying evidence is unlikely; these types of distributed proof systems are likely candidates for use in pervasive computing and sensor network environments. We present modifications to one such distributed proof system that enable three types of consistency constraints to be enforced while still respecting the same confidentiality and integrity policies as the original proof system. We then discuss how these techniques can be adapted and applied to other, less restrictive, distributed proof systems. Further, we detail a performance analysis that illustrates the modest overheads of our consistency enforcement schemes. © 2010 ACM

Routing Protocols for Low Power and Lossy Networks in Internet of Things Applications

The emergence of the Internet of Things (IoT) and its applications has taken the attention of several researchers. In an effort to provide interoperability and IPv6 support for the IoT devices, the Internet Engineering Task Force (IETF) proposed the 6LoWPAN stack. However, the particularities and hardware limitations of networks associated with IoT devices lead to several challenges, mainly for routing protocols. On its stack proposal, IETF standardizes the RPL (IPv6 Routing Protocol for Low-Power and Lossy Networks) as the routing protocol for Low-power and Lossy Networks (LLNs). RPL is a tree-based proactive routing protocol that creates acyclic graphs among the nodes to allow data exchange. Although widely considered and used by current applications, different recent studies have shown its limitations and drawbacks. Among these, it is possible to highlight the weak support of mobility and P2P traffic, restrictions for multicast transmissions, and lousy adaption for dynamic throughput. Motivated by the presented issues, several new solutions have emerged during recent years. The approaches range from the consideration of different routing metrics to an entirely new solution inspired by other routing protocols. In this context, this work aims to present an extensive survey study about routing solutions for IoT/LLN, not limited to RPL enhancements. In the course of the paper, the routing requirements of LLNs, the initial protocols, and the most recent approaches are presented. The IoT routing enhancements are divided according to its main objectives and then studied individually to point out its most important strengths and weaknesses. Furthermore, as the main contribution, this study presents a comprehensive discussion about the considered approaches, identifying the still remaining open issues and suggesting future directions to be recognized by new proposals

Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks

The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs) composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP) involves an artificial immune system (AIS) that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP) that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2) and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks

A comprehensive survey on network anomaly detection

Nowadays, there is a huge and growing concern about security in information and communication technology among the scientific community because any attack or anomaly in the network can greatly affect many domains such as national security, private data storage, social welfare, economic issues, and so on. Therefore, the anomaly detection domain is a broad research area, and many different techniques and approaches for this purpose have emerged through the years. In this study, the main objective is to review the most important aspects pertaining to anomaly detection, covering an overview of a background analysis as well as a core study on the most relevant techniques, methods, and systems within the area. Therefore, in order to ease the understanding of this survey’s structure, the anomaly detection domain was reviewed under five dimensions: (1) network traffic anomalies, (2) network data types, (3) intrusion detection systems categories, (4) detection methods and systems, and (5) open issues. The paper concludes with an open issues summary discussing presently unsolved problems, and final remarks703447489CNPQ - Conselho Nacional de Desenvolvimento Científico e TecnológicoFINEP - Financiadora de Estudos E Projetos249794/2013-6; 309335/2017-5; 308348/2016-801.14.0231.00500008/2013FCT - Fundação para a Ciência e a Tecnologi