Layered Steered Space–Time-Spreading-Aided Generalized MC DS-CDMA

Abstract—We present a novel trifunctional multiple-input– multiple-output (MIMO) scheme that intrinsically amalgamates space–time spreading (STS) to achieve a diversity gain and a Vertical Bell Labs layered space–time (V-BLAST) scheme to attain a multiplexing gain in the context of generalized multicarrier direct-sequence code-division multiple access (MC DS-CDMA), as well as beamforming. Furthermore, the proposed system employs both time- and frequency-domain spreading to increase the number of users, which is also combined with a user-grouping technique to reduce the effects of multiuser interference

Security Implications of the Proliferation of Weapons of Mass Destruction in the Middle East

This monograph addresses the important question of the security implications for the nations of the region of the proliferation of weapons of mass destruction in the Middle East. The Strategic Studies Institute is pleased to offer the monograph as a contribution to the national security debate on this important issue. The author offers a unique perspective based on extensive interviews that he conducted in the region, and makes specific policy recommendations for U.S. military and civilian decisionmakers.https://press.armywarcollege.edu/monographs/1851/thumbnail.jp

U.S. Military Presence in the Persian Gulf: Challenges and Prospects

The author considers the critical questions of U.S. military presence in the Gulf, the challenges it faces, and the prospects that lay ahead. He relies, in his presentation and analysis, on a variety of regional sources including newspaper reports and personal interviews conducted in the United States and the Gulf region, as well as government and academic sources. The result is a comprehensive study, including policy recommendations for U.S. military and civilian decisionmakers that makes intelligible the complex subject of U.S.-Gulf relations.https://press.armywarcollege.edu/monographs/1826/thumbnail.jp

Hizballah: Terrorism, National Liberation, or Menace?

The author reviews the history of Hizballah since its inception in 1982, and examines its role in the recent political turmoil of Lebanon and the region. Not only is Hizballah\u27s role central in the dispute over the Sheb\u27a Farms enclave between Lebanon and Israel, it is part of an entangled set of linkages involving Syria, Iran, the United States, the European Union, and the Palestinians. The challenge that Hizballah poses to U.S. policy in the Middle East involves complicated strategic issues, not merely problems of terrorism that could be dealt with by countermeasures.https://press.armywarcollege.edu/monographs/1818/thumbnail.jp

On the performance of key pre-distribution for RPL-based IoT Networks

A core ingredient of the the Internet of Things (IoT) is the use of deeply embedded resource constrained devices, often connected to the Internet over Low Power and Lossy Networks. These constraints compounded by the need for unsupervised operation within an untrusted environment create considerable challenges for the secure operation of these systems. In this paper, we propose a novel method to secure an edge IoT network using the concept of key pre-distribution proposed by Eschenauer and Gligor in the context of distributed sensor networks. First, we investigate the performance of the unmodified algorithm in the Internet of Things setting and then analyse the results with a view to determine its performance and thus its suitability in this context. Specifically, we investigate how ring size influences performance in order to determine the required ring size that guarantees full connectivity of the network. We then proceed to propose a novel RPL objective function and associated metrics that ensure that any node that joins the network can establish secure communication with Internet destinations. , N., , H., , Th., , Th., , A., , P

Secure routing in IoT networks with SISLOF

In this paper, we propose a modification of the RPL routing protocol by introducing the SISLOF Objective Function ensuring that only motes that share a suitable key can join the RPL routing table. This will ensure that all IoT network motes connect in a secure method. SISLOF uses the concept of key pre-distribution proposed by Eschenauer and Gligor in the context of the Internet of Things. First, we discuss related work that provide evidence that the key pre-distribution scheme in the context of the IoT with default RPL metrics fails to achieve the full network connectivity using the same ring size, however full time connectivity can be achieved but with a great cost in term of the large rings sizes. We introduce the SISLOF Objective Function and explain the modification it does to the RPL messages (DIO and DAO). We finally show the performance of the key pre-distribution in the context of the Internet of Things when SISLOF is used as the Objective Function of the RPL routing protocol

Iteratively Decoded Irregular Variable Length Coding and Sphere-Packing Modulation-Aided Differential Space-Time Spreading

In this paper we consider serially concatenated and iteratively decoded Irregular Variable Length Coding (IrVLC) combined with precoded Differential Space-Time Spreading (DSTS) aided multidimensional Sphere Packing (SP) modulation designed for near-capacity joint source and channel coding. The IrVLC scheme comprises a number of component Variable Length Coding (VLC) codebooks having different coding rates for the sake of encoding particular fractions of the input source symbol stream. The relative length of these source-stream fractions can be chosen with the aid of EXtrinsic Information Transfer (EXIT) charts in order to shape the EXIT curve of the IrVLC codec, so that an open EXIT chart tunnel may be created even at low Eb/N0 values that are close to the capacity bound of the channel. These schemes are shown to be capable of operating within 0.9 dB of the DSTS-SP channel’s capacity bound using an average interleaver length of 113, 100 bits and an effective bandwidth efficiency of 1 bit/s/Hz, assuming ideal Nyquist filtering. By contrast, the equivalent-rate regular VLC-based benchmarker scheme was found to be capable of operating at 1.4 dB from the capacity bound, which is about 1.56 times the corresponding discrepancy of the proposed IrVLC-aided scheme

The Change of the Vessel Markings by Ligation of the Branch of the Pulmonary Artery

In relation with the collapse therapy of the lung, I observed the change of vessel markings of the lobe when the secondary atrophy of the lung occurs by ligation of pulmonary artery. Using a cat weighing 2-3 kg, I obtained specimens by infusing dyes in a living cat at various periods after operation. The results were as follows. 1) There were observed no dangerous symptoms by the ligation of the branch of the pulmonary artery. The necrosis of the ligated lobe did not occur. 2) Directly after the ligation there occurs a formation of a collateral pathway by a capillary communication from the vessels of the bronchial wall which extends to the wall of the alveolus, then by the newly built vessels which came outside the lobe through the adhesion with the peripheral area of it. 3) By ligation a thrombus will be formed in the pulmonary artery but a circulating pathway can be noticed inside the thrombus. This is considered to be a circulating pathway retrogradely to the pulmonary artery through the capillary net work of the alveolus wall by the vessels of the bronchial walls and the vessels which invaded from the outside of the lobe through the adhering portion. A week after the ligation the thrombus is nearly absorbed and the recovery of the circulation inside the pulmonary artery can be noticed. 4) The change of the lobe which occurs by the ligation of the branch of the pulmonary artery can be applied clinically