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The selection of an optimized gas adsorption model is a quantitatively challenging task when characterizing shale gas reservoirs because every model has its own assumptions and mechanisms. In addition, excess when converting different models to absolute gas adsorption is reported in the literature, which differs due to variations in adsorbed phase density or volume. The roles of controlling factors change under various conditions and consequences, and it is hard to comprehend shale storage and production sources. Quantifying the contribution of adsorbed and absorbed gases to total gas storage is also challenging despite existing advanced techniques. This paper reviews gas adsorption in the light of applications, comparisons and challenges along with shale controlling factors, and it provides a better opportunity to comprehend shale storage and platforms to investigate further mechanisms of shale gas storage. It is revealed in this review that several crucial factors are found in shale that control and affect the gas adsorption capacity. Kerogen swelling and pore shrinkage, kerogen maturity, gas type and moisture content greatly influence gas adsorption capacity. The measurement of true adsorbed and bulk amount, selection of an optimized gas adsorption model, proper investigation of shale controlling factors, and accurate measurement of adsorbed and absorbed gases may enhance the accuracy of resource assessment and production performance predictions.

The current work is an attempt to know that in which fraction(s) the relaxant constituents of Rosa moschata concentrate. Crude methanolic extract of Rosa moschata was prepared as per our reported procedure. Sub fractions of methanol extract were extracted with different solvents in increasing order of polarity i.e. n-hexanechloroformethyl acetaten-butanolresidual aqueous fractions. Different concentrations (0.01, 0.03, 0.1, 0.3, 1, 3, 5 and 10 mg/ml) of the fractions were tested on spontaneous contractions and KCl induced contractions on rabbits' jejunal preparations. Calcium Concentration Response Curves (CCRCs) in the presence and absence of the test fractions using verapamil were constructed to understand its mechanisms. EtOA fraction was more relaxant with EC

OBJECTIVE: To evaluate the saponins rich fraction of Dioscorea deltoidea (D. deltoidea) for possible antinociceptive activity. METHODS: Saponins were extracted from the crude methanolic extract of D. deltoidea (Wall). Presence of saponins was confirmed through phytochemical screenings. Acute toxicity test was performed to determine safe dose range of the saponins rich fraction (n-butanol fraction) using balb C Mice. The saponins rich fraction was assessed for possible antinociceptive activity using acetic acid induced writhing method and hot plate method. Data was analyzed using Graph Pad Prism 6. ANOVA was used to determine the significance of test samples versus positive control at 95% CI with p

Gas condensate reservoirs usually exhibit complex flow behaviors because of propagation response of pressure drop from the wellbore into the reservoir. When reservoir pressure drops below the dew point in two phase flow of gas and condensate, the accumulation of large condensate amount occurs in the gas condensate reservoirs. Usually, the saturation of condensate accumulation in volumetric gas condensate reservoirs is lower than the critical condensate saturation that causes trapping of large amount of condensate in reservoir pores. Trapped condensate often is lost due to condensate accumulation-condensate blockage courtesy of high molecular weight, heavy condensate residue. Recovering lost condensate most economically and optimally has always been a challenging goal. Thus, gas cycling is applied to alleviate such a drastic loss in resources. In gas injection, the flooding pattern, injection timing and injection duration are key parameters to study an efficient EOR scenario in order to recover lost condensate. This work contains sensitivity analysis on different parameters to generate an accurate investigation about the effects on performance of different injection scenarios in homogeneous gas condensate system. In this paper, starting time of gas cycling and injection period are the parameters used to influence condensate recovery of a five-spot well pattern which has an injection pressure constraint of 3000 psi and production wells are constraint at 500 psi min. BHP. Starting injection times of 1 month, 4 months and 9 months after natural depletion areapplied in the first study. The second study is conducted by varying injection duration. Three durations are selected: 100 days, 400 days and 900 days. In miscible gas injection, miscibility and vaporization of condensate by injected gas is more efficient mechanism for condensate recovery. From this study, it is proven that the application of gas cycling on five-spot well pattern greatly enhances condensate recovery preventing financial, economic and resource loss that previously occurred.

A large amount of residual oil, which exists as isolated oil slugs, remains trapped in reservoirs after water flooding. Numerous numerical studies are performed to investigate the fundamental flow mechanism of oil slugs to improve flooding efficiency. Dynamic contact angle models are usually introduced to simulate an accurate contact angle and meniscus displacement of oil slugs under a high capillary number. Nevertheless, in the oil slug flow simulation process, it is unnecessary to introduce the dynamic contact angle model because of a negligible change in the meniscus displacement after using the dynamic contact angle model when the capillary number is small. Therefore, a critical capillary number should be introduced to judge whether the dynamic contact model should be incorporated into simulations. In this study, a direct numerical simulation method is employed to simulate the oil slug flow in a capillary tube at the pore scale. The position of the interface between water and the oil slug is determined using the phase-field method. The capacity and accuracy of the model are validated using a classical benchmark: a dynamic capillary filling process. Then, different dynamic contact angle models and the factors that affect the dynamic contact angle are analyzed. The meniscus displacements of oil slugs with a dynamic contact angle and a static contact angle (SCA) are obtained during simulations, and the relative error between them is calculated automatically. The relative error limit has been defined to be 5%, beyond which the dynamic contact angle model needs to be incorporated into the simulation to approach the realistic displacement. Thus, the desired critical capillary number can be determined. A three-dimensional universal chart of critical capillary number, which functions as static contact angle and viscosity ratio, is given to provide a guideline for oil slug simulation. Also, a fitting formula is presented for ease of use.

This paper is totally based on iris recognition and biometrics comparison techniques. Author revealed the story of iris recognition and biometrics comparison and provided the step by step detail about iris biometrics recognition and also elaborated the use of iris recognition and mentioned the key role played by it in daily life.

Summary Most sensor networks are deployed at hostile environments to sense and gather specific information. As sensor nodes have battery constraints, therefore, the research community is trying to propose energy-efficient solutions for wireless sensor networks (WSNs) to prolong the lifetime of the network. In this paper, we propose an energy-efficient multi-level and distance-aware clustering (EEMDC) mechanism for WSNs. In this mechanism, the area of the network is divided into three logical layers, which depends upon the hop-count-based distance from the base station. The simulation outcomes show that EEMDC is more energy efficient than other existing conventional approaches. Copyright © 2013 John Wiley & Sons, Ltd.

Increasing use of wireless networks has empowered the facility of ubiquitous health monitoring especially in advanced countries. Various small devices are attached to human body forming personalized wireless body area network (WBAN). These small devices interact with each other using different radios and antennas sc hemes proposed by many researchers around the globe. However, most of these schemes are facing problem of inefficiency due to fading and shadowing effects. We propose a novel multi-radio multi- channel framework for efficient communication among devices in WBAN. The focus of this research is to ensure energy efficient and reliable communication in WBAN.

Today with certainty, the petroleum industry is fostering sanguinely the fields’ development programs for the optimization of reservoir characterization through worth-full appliances of computer analysis techniques. The time element is of prime importance for optimistic petroleum development projects. Therefore, the frontline of “Real-time Analysis” is added into the applications of computer solving techniques for achieving and sketching up the real-time cost effectiveness in analyzing field development programs. It focuses on the phases of real-time well test data acquisition system, real-time secure access to the well test data either on field or in office and real-time data interpretation unit. This interface will yield the productive results for the field of reservoir’s pressure transient analysis and wells’ systems analysis by following the up-to-date preferred, accurate and effective well test analytical principles with modern real-time computer applications and techniques. It also lays emphasis for the comfort and reliability of data in creating best interpersonal working modes within a reputable and esteemed petroleum development organization.

As now-days drilling depths penetrating deeper for exploiting more reserves, hence the gaseous phase exist especially whose phase envelop lies near to critical point. From available literature, it is evident that near critical fluids are of complex phenomena due to intensive compositional change even with respect to very little change in pressure gradient. Hence for gas condensate reservoirs, especial methods for PVT analysis like Whitson and Torp K-Value method is currently used in industry to evaluate effectively the PVT properties even below the saturation pressure. On the basis of Whitson and Torp method and their available PVT equations, the material balance equation for gas condensate reservoir is required and explained in this paper as the conventional material balance is not applicable on near critical fluid reservoirs because it does not contain standard PVT properties solutions below the saturation pressure. The application of material balance equation for gas condensate reservoirs is highlighted to calculate the initial reserves and gas in-places that valuably assist in designing production development strategy and economic evaluations. Gas in-places are estimated and calculated by using application of Havlenah-Odeh plot methods and compared with conventional analysis of Pressure Decline method. Paper explanations are raised with intentions of good assistance to the petroleum industry in estimating gas condensate reserves to implementing pragmatic future development decisions.

We propose a new decoding procedure for non-binary cluster-LDPC codes based on the observation that different non-binary Tanner graphs for the same binary code may result in different convergence behaviours. We apply this concept locally at the check nodes and use multiple instances of a check node in parallel. Their outputs are joined together to get a single extrinsic message for each edge of the node. Each instance uses the famous Extended-Min-Sum (EMS) algorithm with very low complexity. We are able to obtain better decoding performance in the error-floor region with equal or lower complexity. We obtain the results via Mont-Carlo simulations and we make a comparison of the complexities as well.

The important function of a sensor network is to collect and forward data to destination. It is very important to know about the location of collected data. This kind of information can be obtained using localization technique in wireless sensor networks (WSNs). Localization is a way to determine the location of sensor nodes. Localization of sensor nodes is an interesting research area, and many works have been done so far. It is highly desirable to design low-cost, scalable, and efficient localization mechanisms for WSNs. In this paper, we discuss sensor node architecture and its applications, different localization techniques, and few possible future research directions.

Wireless Sensor Networks (WSNs) consist of sensor nodes deployed in a manner to collect information about surrounding environment. Their distributed nature, multihop data forwarding, and open wireless medium are the factors that make WSNs highly vulnerable to security attacks at various levels. Intrusion Detection Systems (IDSs) can play an important role in detecting and preventing security attacks. This paper presents current Intrusion Detection Systems and some open research problems related to WSN security.

Nowadays the energy demand has become tripled resulting in advancingof the development activities in the petroleum industry to enhance hydrocarbon recoveries. It is reviewed from the literature that the current worldwide facts of research and technical observations have proved that the coal containing methane gas is not much efficient in terms of power, cost and environment friendly energy source. The objective of this research is to determine the technical and economic feasibility of carbon dioxide (CO2) and nitrogen gas (N2). Moreover, sequestration in coal seams and their environmental consequences for coal based methane recovery project. This research study is also covers the effective and efficient methodologyforextraction of methane gas from coal, which is coupled with the injection of CO2 and N2 into the coal seam complex structure. Moreover, this methodology is applied individually and simultaneously, along with the after effects of injection of CO2 and N2 on Coal bed methane (CBM) recovery. The results of this research study suggestsa method for generation of electric power in which CBM gas is used as an input source whilst the combustion gas, CO2 emissions are sequestrated into coal seams for environmental protection, extending the CBM recovery and reducing CO2 availability cost.

In this paper, we propose an improvement of the previously proposed decoder for split LDPC codes defined over finite groups. The output of the check nodes is adjusted such that it bears better resemblance to that of more complex and efficient algorithms. There is a significant improvement in the decoding performance with almost no oeffect on the decoding complexity. The hardware architecture for the proposed decoder is explained in detail and we show with Monte-Carlo simulations that the performance is indeed improved.

In this paper, we propose a practically implementable decoding algorithm for split LDPC codes with parity constraints defined over finite groups. The proposed decoding algorithm generalizes the orders of the variable and check nodes such that it may have messages of different order at the various nodes. This gives us a further degree of freedom in terms of better code construction. Using the binary image of the parity check matrix, we define the function node which maps lower order messages to higher order and vice-versa. In order to have a reduced compexity decoder which is practically implementable, we use the truncated messages concept at the check nodes and evaluate its performance. We show improved performance in the error floor region as compared to other non-split low complexity decoding algorithms.