Integrated Circuit and System Design for Cognitive Radio and Ultra-Low Power Applications

The ubiquitous presence of wireless and battery-powered devices is an inseparable and invincible feature of our modern life. Meanwhile, the spectrum aggregation, and limited battery capacity of handheld devices challenge the exploding demand and growth of such radio systems. In this work, we try to present two separate solutions for each case; an ultra-wideband (UWB) receiver for Cognitive Radio (CR) applications to deal with spectrum aggregation, and an ultra-low power (ULP) receiver to enhance battery life of handheld wireless devices. Limited linearity and LO harmonics mixing are two major issues that ultra-wideband receivers, and CR in particular, are dealing with. Direct conversion schemes, based on current-driven passive mixers, have shown to improve the linearity, but unable to resolve LO harmonic mixing problem. They are usually limited to 3rd, and 5th harmonics rejection or require very complex and power hungry circuitry for higher number of harmonics. This work presents a heterodyne up-down conversion scheme in 180 nm CMOS technology for CR applications (54-862 MHz band) that mitigates the harmonic mixing issue for all the harmonics, while by employing an active feedback loop, a comparable to the state-of-the art IIP3 of better than +10 dBm is achieved. Measurements show an average NF of 7.5 dB when the active feedback loop is off (i.e. in the absence of destructive interference), and 15.5 dB when the feedback loop is active and a 0 dBm interferer is applied, respectively. Also, the second part of this work presents an ultra-low power super-regenerative receiver (SRR) suitable for OOK modulation and provides analytical insight into its design procedure. The receiver is fabricated in 40 nm CMOS technology and operates in the ISM band of 902-928 MHz. Binary search algorithm through Successive Approximation Register (SAR) architecture is being exploited to calibrate the internally generated quench signal and the working frequency of the receiver. Employing an on-chip inductor and a single-ended to differential architecture for the input amplifier has made the receiver fully integrable, eliminating the need for external components. A power consumption of 320 µW from a 0.65 V supply results in an excellent energy efficiency of 80 pJ/b at 4 Mb/s data rate. The receiver also employs an ADC that enables soft-decisioning and a convenient sensitivity-data rate trade-off, achieving sensitivity of -86.5, and -101.5 dBm at 1000 and 31.25 kbps data rate, respectivel

Robust Distributed Stabilization of Interconnected Multiagent Systems

Many large-scale systems can be modeled as groups of individual dynamics, e.g., multi-vehicle systems, as well as interconnected multiagent systems, power systems and biological networks as a few examples. Due to the high-dimension and complexity in configuration of these infrastructures, only a few internal variables of each agent might be measurable and the exact knowledge of the model might be unavailable for the control design purpose. The collective objectives may range from consensus to decoupling, stabilization, reference tracking, and global performance guarantees. Depending on the objectives, the designer may choose agent-level low-dimension or multiagent system-level high-dimension approaches to develop distributed algorithms. With an inappropriately designed algorithm, the effect of modeling uncertainty may propagate over the communication and coupling topologies and degrade the overall performance of the system. We address this problem by proposing single- and multi-layer structures. The former is used for both individual and interconnected multiagent systems. The latter, inspired by cyber-physical systems, is devoted to the interconnected multiagent systems. We focus on developing a single control-theoretic tool to be used for the relative information-based distributed control design purpose for any combinations of the aforementioned configuration, objective, and approach. This systematic framework guarantees robust stability and performance of the closed-loop multiagent systems. We validate these theoretical results through various simulation studies

New fixed point results in b-rectangular metric spaces

In this work, the class of b-rectangular metric spaces is introduced, some fixed point results dealing with rational type contractions and almost generalized weakly contractive mappings are obtained. Certain examples are given to support the results

Assessment of Dysregulation of HERC6 and Essential Biological Processes in Response to Laser Therapy of Human Arm Skin

Introduction: The widespread application of lasers in medicine, especially in the treatment of diseases implies more investigations to understand the precious molecular mechanism of the laser effect on the human body. In the present study, the prominent role of HERC6 in response to CO2 Laser therapy of human skin is investigated.Methods: The numbers of 16 gene expression profiles before and after the treatment with the CO2 laser are downloaded from Gene Expression Omnibus (GEO), and differentially-expressed genes (DEGs) are analyzed to find the significant DEGs. Gene ontology analysis revealed that HERC6 and a set of its neighbors played a significant role in response to laser application.Results: The expression changes of 52 significant DEGs were compared via heat map analysis and 27 significant DEGs were introduced as the critical genes which are involved in response to laser irradiation. “Thymidylate kinase activity” among 9 clusters of biological terms was highlighted as an important biological process related to the identified DEGs. HERC2 was proposed as a critical DEG which was related to several essential cellular processes in response to laser application.Conclusion: The findings from the present study indicate that HERC6 and the numbers of its first neighbors are involved in the essential cellular response to laser therapy of human skin

Analysis of Laser Therapy Effects on Squamous Cell Carcinoma Patients: A System Biology Study

Introduction: Mechanism of Laser therapy and also its safety are two important features of application of different types of laser in medicine. Aim of this study is investigating the critical affected genes after treatment of squamous cell carcinoma patients.Methods: Gene expression profiles of 4 squamous cell carcinoma patients that are treated via chemoradiotherapy plus laser relative to the 3 similar patients without laser exposure from Gene Expression Omnibus (GEO) are downloaded and are screen to find critical genes via network analysis. STRING database, Cytoscape software, and Clue GO plug in of Cytoscape software are used.  Results: The genes; HSX70 and NCC27 as neighbors and HSPA1B, CLIC1, RAB13, PPIF, and LCE3D were determined as hub genes. Over-expression of LCE3D was interpreted as side effect of laser therapy. Apoptosis and cell cycle were the dominant biological processes that regulated by the HSP molecules in laser treated patients.Conclusion: Laser was effected the main biological processes and simultaneously issued side effects.

Assessment of Laser Effects on Skin Rejuvenation

Laser skin resurfacing has changed the approach of facial skin rejuvenation over the past decade. This article evaluates the laser effects on skin rejuvenation by the assessment of laser characteristics and histological and molecular changes, accompanied by the expression of proteins during and after laser-assisted rejuvenation of skin. It is important to note that different layers of skin with different cells are normally exposed to the sun’s UV radiation which is the most likely factor in aging and damaging healthy skin. To identify the expression of proteins, using validated databases and reviewing existing data could reveal altered proteins which could be analyzed and mapped to investigate their expression and their different effects on cell biological responses. In this regard, proteomics data can be used for better investigation of the changes in the proteomic profile of the treated skin. Different assessments have revealed the survival and activation of fibroblasts and new keratinocytes with an increase of collagen and elastin fibers in the dermis and the reduction of matrix metalloproteinases (MMPs) and heat shock proteins (HSPs) as a result of different low-power laser therapies of skin. There are a wide range of biological effects associated with laser application in skin rejuvenation; therefore, more safety considerations should be regarded in the application of lasers in skin rejuvenation

Evaluation of Efficacy of Low-Level Laser Therapy

Introduction: Given the inconsistencies in the literature regarding laser performance in non-surgical treatments, this study investigated the available literature to determine the advantages and disadvantages of low-power lasers in treating non-surgical complications and diseases.Methods: Authentic information from articles was extracted and evaluated to assess low-power laser performance for non-surgical treatments. A systematic search of studies on low-level laser therapy (LLLT) for non-surgical treatments was conducted mainly in PubMed and google scholar articles.Results: Four categories of diseases, including brain-related diseases, skin-related diseases, cancers, and bone-related disorders, which were treated by LLLT were identified and introduced. The various types of LLLT regarding the studied diseases were discussed.Conclusion: Positive aspects of LLLT versus a few disadvantages of its application imply more investigation to find better and efficient new methods

Dynamic Multi-Level Generation and Transmission Expansion Planning Model of Multi-Carrier Energy System to Improve Resilience of Power System

Since the presence of an energy hub (EH) leads to change the expansion planning problem of electrical power system. Therefore, in this study, the nature of optimal generation and transmission expansion planning in the presence of EH is studied. Also, the effect of applying the proposed hub with and without considering energy storages (ESs) as well as the short and long-term corrective actions to reduce the losses and costs are investigated. In addition, demand response and line transmission switching are considered as effective approaches to improve resilience in the proposed dynamic multi-level model. This nonlinear problem is solved sequentially considering the random approach and using differential evolution algorithm (DEA) and the symphony orchestra search algorithm (SOSA). In this paper, the proposed objective functions are studied in five-level and the results show the efficiency of this model in solving the planning problem. The findings show that the proposed planning model decreased capital costs of transmission switches as much as 26%, the capital cost of the transmission as much as 2.29%, the congestion cost as much as 1.8%, The capital cost of generation units as much as 3.75%, the payment capacity paid to generation units as much as 1.8%. Also, the expected profit of the generation units has increased as much as 3.75%. To show the competence of the proposed algorithms, the 400-kV test system with 52 buses in Iran is simulated in MATLAB environment

Investigation of Crucial Affected Proteins in Rat Liver in the Presence of Scrophularia

Background and objectives: Radix Scropholaria is dried root Scrophularia ningpoensis Hemsl. which is used uses as a drug against several diseases. In the present study, the crucial affected proteins of rat liver in the presence of radix Scrophularia have been investigated. Methods: The differentially expressed proteins (DEPs) were downloaded from literature. The significant DEPs plus 100 added first neighbors were determined and included in “protein query” of STRING database via Cytoscape software. The network was analyzed and the central nodes among the queried DEPs were identified. The 10 first neighbors of the central DEPs were determined. Results: RT1-CE12, Gfer, Serpina3c, Rab13, Rbm14, Ighg Psmb8, COX2, Olr796, Mga, Ugt1a6, Ugt2b, Ebpl, Ugt2b, Igf2r, and Amacr as significant DEPs were analyzed via protein-protein interaction (PPI) network analysis, Ugt1a1 and Ugt2b the two up-regulated proteins were highlighted as the crucial proteins in response to the radix Scrophularia. Conclusion: Two members of UDP glucuronosyltransferase family; Ugt1a1 and Ugt2b, were pointed as the critical liver enzyme which are dysregulated under effect of radix Scrophulariae. Due to crucial role of Ugt1a1 in the liver function, it is suggested that consumption of Scrophularia ningpoensis Hemsl. as a traditional medicine required more investigation