Double-Sampling Single-Loop EA Modulator Topologies for Broad-band Applications

This paper presents novel double sampling high-order single loop sigma-delta modulator structures for wide-band applications. To alleviate the quantization noise folding into the inband frequency region, two previously reported techniques are used. The digital-to-analog converter's sampling paths are implemented with the single-capacitor approach and an additional zero is placed at the half of the sampling frequency of the modulator's noise transfer function (NTF). The detrimental effect of this additional zero on both the NTF and signal transfer function is also resolved through the proposed modulator architectures with a low additional circuit requirement

Double-sampled cascaded sigma-delta modulator topologies for low oversampling ratios

This paper presents novel double-sampling cascaded sigma-delta modulator topologies for wideband applications. The proposed modulator structures employ finite impulse response (FIR) noise transfer function (NTF) to achieve the aggressive noise shaping with an additional zero at the half of the sampling frequency to alleviate the quantization noise folding. Cascading of the proposed modulator structures is very simple without any additional circuit requirements.Comisión Interministerial de Ciencia y Tecnología TIC2003-0235

A Review of Shahriar's Persian Divan Words

The main objective of this study is to review the vocabulary reservoir of Shahriar's Divan linguistically. He has spent a lot of time on creating literary style. His works still maintain its artistic effects. His literary speech still interests every reader to be curious about the history of the evolution of literary form of Persian language. As this is the first study that has been done in the field of the vocabulary reservoir of Shahriar's Persian Divan, Persian Philology categories have been fully presented, the verbal and semantic characteristics of Persian vocabulary reservoir are reflected. Throughout the divan, synonyms have a distinctive feature. Other categories of words such as antonyms, kinds of figures of speech, allusions, simile, metaphor, bilingualism are of important subjects. Selection of the appropriate rhymes is evident in Divan. Shahriar's Divan has also been reviewed linguistically by studying its meaningful examples of poetry. In this study, the volumes published in 2006 have been used. Selecting proper rhymes is evident in Divan. Using antonyms creates various positions and occasions in stylistics

Development of graphical user interface tools for optimal fluid management in shale oil and gas operations

Includes bibliographical references.2015 Fall.Oil and gas extraction is increasing in many parts of the country due to the use of hydraulic fracturing. Hydraulic fracturing is a technique to extract oil and gas from shale rock formations that is characterized by the input of large quantities of pressurized water into horizontal wells. The high pressure fluid generates cracks in the shale formation that release the gas, oil, and other constituents into the fluid. The fluid that returns to the surface is characterized as flowback or produced water. Flowback is defined as the water that returns to the surface prior to the initiation of oil or gas production and produced water refers to the post-production return water. There is widespread public and government agency interest in assessing the quantity and quality of water used in hydraulic fracturing to ensure environmental protection and public health. Optimal water management in hydraulic fracturing has the potential to (1) reduce freshwater use, (2) increase produced water recycle, (3) reduce energy expenditures from water transport, and (4) enhance safety and environmental protection in the development of natural gas and other petroleum resources. Improved management of water can enhance safety and environmental protection by minimizing impacts such as road damage, truck traffic, noise, air pollution, water pollution and landscape disturbance. Interactive management tools allow operators to increase water reuse and minimize the environmental risks of hydraulic fracturing. This research entails developing graphical user tools to optimize water management in shale oil and gas operations. The tools that were developed include (1) a Water Production Modeling Tool, (2) a Water Use Calculator, and (3) a Water Quality Tool. The tools are MATLAB executable files that can run without a MATLAB license. The output of these tools will provide information for users to predict wastewater production, water demand needed for treatment, and analyze water quality components such as contaminant concentrations

A Supervisory Control Algorithm Based on Property-Directed Reachability

We present an algorithm for synthesising a controller (supervisor) for a discrete event system (DES) based on the property-directed reachability (PDR) model checking algorithm. The discrete event systems framework is useful in both software, automation and manufacturing, as problems from those domains can be modelled as discrete supervisory control problems. As a formal framework, DES is also similar to domains for which the field of formal methods for computer science has developed techniques and tools. In this paper, we attempt to marry the two by adapting PDR to the problem of controller synthesis. The resulting algorithm takes as input a transition system with forbidden states and uncontrollable transitions, and synthesises a safe and minimally-restrictive controller, correct-by-design. We also present an implementation along with experimental results, showing that the algorithm has potential as a part of the solution to the greater effort of formal supervisory controller synthesis and verification.Comment: 16 pages; presented at Haifa Verification Conference 2017, the final publication is available at Springer via https://doi.org/10.1007/978-3-319-70389-3_

A new structure for capacitor-mismatch-insensitive multiply-by-two amplification

A new approach to achieve a switched-capacitor multiply-by-two gain-stage with reduced sensitivity to capacitors' mismatches is presented in this paper. It is based on sampling fully differential input signals onto both plates of the input capacitors rather than sampling onto one plate of the capacitors with the other tied to a reference. It uses one operational amplifier (op-amp) in two phases to produce the gain of two (/spl times/2). Comparing to the conventional multiply-by-two gain-stage, the mismatches between the capacitors has a much smaller influence on the accuracy of the gain of two (/spl times/2). Analytical and circuit-level analysis of the architecture and the conventional structure are presented using a generic 0.35/spl mu/m CMOS technology

Symbolic Interpretation and Execution of Extended Finite Automata

We introduce a symbolic interpretation and execution technique for Extended Finite Automata (EFAs) and provide an interpreter that symbolically interprets and executes EFAs w.r.t. their (internal) variables. More specifically, the interpreter iterates over the EFA transitions, and by passing each transition, it symbolically interprets and evaluates the condition on the transition w.r.t. the known values of variables, and leaves other variables intact, and when it terminates, it returns the residual model. It is shown that the behavior of the residual system with respect to the original system is left unchanged. Finally, we demonstrate the effectiveness and necessity of the symbolic interpretation and execution combined with abstractions for the nonblocking supervisory control of two manufacturing systems

Investigation the Antioxidant and the Antimicrobial Effects of Aqueous and Ethanolic Extract of Astragals. on In-vitro Indicator Microorganisms

Abstract: Extraction was performed by using maceration method for dried flower sample. Then, the antimicrobial effect of aqueous and ethanolic extracts on eight bacterial sp. and two fungi were tested using disc diffusion method. The antioxidant effect was also determined through ferric reducing potency and phosphor molybdenum followed by total phenol determination.  Introduction: The Astragals. is high in certain antioxidants. The fruit is noted for its high level of vitamin C, and is used to make syrup, tea, and marmalade. It has been grown or encouraged in the wild for the production of vitamin C from its fruit (often as rose-hip syrup), especially during conditions of scarcity or during wartime. The species has also been introduced to other temperate latitudes. During World War II in the United States, Rosa canina was planted in victory gardens, and can still be found growing throughout the country, including roadsides and in wet, sandy areas along the coastlines. Methods and Results: Extraction was performed by using maceration method for dried flower sample. Then, the antimicrobial effect of aqueous and ethanolic extracts on eight bacterial sp. and two fungi were tested using disc diffusion method. The antioxidant effect was also determined through ferric reducing potency and phosphomolybdenum followed by total phenol determination. Finally, partial detection of bioactive compounds was conducted using chemical and calorimetric methods. The results showed that ethanolic extract had the most antimicrobial effect; while aqueous extract weakly affected bacterial and fungal strains. Antioxidant experiments also revealed that ethanol extract had more antioxidant effects than aqueous extract. The most content of total phenolic compounds was found in ethanol extract. The results of the plant chemical determination showed the presence of flavonoids, alkaloids, anthraquinones, tannins, glycosides, and reducing sugars. Conclusions: Considering that few reports about the therapeutic effect of Astragals. has been published, this study could be considered as a valuable report about the important role of this plant on preventing infections and neutralizing oxidant agents