A GIS Database for Sustainable Management of Shallow Water Resources in the Tulul al Ashaqif Region, NE Jordan

The Tulul al Ashaqif region is an arid area in northeastern Jordan that contains renewable shallow perched aquifer water. The study of these aquifers has led to better understanding of the recharge process as well as other hydrological issues related to management of water resources in similar areas. The use of geographic information system (GIS)-based predictive mapping to locate areas of high potential for shallow perched aquifer sites is explored in this paper. Knowledge of the hydrologic, geologic and geomorphic variables influencing the development of shallow aquifer formation is used to produce GIS layers representing the spatial distribution of those variables. The GIS layers are then analyzed to identify locations where combinations of environmental variables match patterns observed at known sites. In addition, information can be deduced on the volume of water that is available and the best locations to site recharge facilities. Moreover, future development of these resources requires consideration of possible adverse affects of usage on these resources. The database developed can be used for this purpose as well.     

Structure–Function Relationship of Retinal Ganglion Cells in Multiple Sclerosis

The retinal ganglion cells (RGC) may be considered an easily accessible pathophysiological site of degenerative processes in neurological diseases, such as the RGC damage detectable in multiple sclerosis (MS) patients with (HON) and without a history of optic neuritis (NON). We aimed to assess and interrelate RGC functional and structural damage in different retinal layers and retinal sites. We included 12 NON patients, 11 HON patients and 14 healthy controls for cross-sectional multifocal pattern electroretinography (mfPERG) and optical coherence tomography (OCT) measurements. Amplitude and peak times of the mfPERG were assessed. Macula and disc OCT scans were acquired to determine macular retinal layer and peripapillary retinal nerve fiber layer (pRNFL) thickness. In both HON and NON patients the foveal N2 amplitude of the mfPERG was reduced compared to controls. The parafoveal P1 peak time was significantly reduced in HON only. For OCT, parafoveal (pfGCL) and perifoveal (pGCL) ganglion cell layer thicknesses were decreased in HON vs. controls, while pRNFL in the papillomacular bundle sector (PMB) showed reductions in both NON and HON. As the mfPERG derived N2 originates from RGC axons, these findings suggest foveal axonal dysfunction not only in HON, but also in NON patients.     

Adsorption desalination of chloride ions on composite natural–synthetic materials: An approach for the reduction of chlorine corrosion in electrodeionization units

The release of chlorine in the electrodeionization (EDI) unit causes corrosion in the EDI unit, damaging ion exchange membranes and creating a safety risk for the workers. In this work, adsorption desalination of Cl^? ions on low-cost composite synthetic–natural Jordanian materials were investigated as an approach to prevent the release of corrosive chlorine gas at the positive electrode. The percentage removal reaches 25% at 25 min shaking time to 55% at 120 min, in a single batch experiment. The values of ΔH⁰, ΔS⁰, and ΔG⁰ indicate the favorability of physisorption. Zeolite and Pozzolana represent potential adsorbents of chloride.     

Extended Rama Distribution: Properties and Applications

In this paper, the Rama distribution (RD) is considered, and a new model called extended Rama distribution (ERD) is suggested. The new model involves the sum of two independent Rama distributed random variables. The probability density function (pdf) and cumulative distribution function (cdf) are obtained and analyzed. It is found that the new model is skewed to the right. Several mathematical and statistical properties are derived and proved. The properties studied include moments, coefficient of variation, coefficient of skewness, coefficient of kurtosis and moment generating function. Some simulations are undertaken to illustrate the behavior of these properties. In addition, the reliability analysis of the distribution is investigated through the hazard rate function, reversed hazard rate function and odds function. The parameter of the distribution is estimated based on the maximum likelihood method. The distributions of order statistics for ERD are also presented. The performance of the suggested model is compared with several other lifetime distributions based on some goodness of fit tests on a real dataset. It turns out that the suggested model is more flexible than its competitors considered in this study, for modeling real lifetime data.     

Compact low-power time-based conversion with noise immunity similar to digital conversion

An analog signal representation based on the inter-pulse-interval (IPI) time is presented. Voltage-to-IPI and IPI-to-voltage conversion circuits based on the representation are described. The circuits have been fabricated using a 0.35 μm mixed-signal CMOS process. Simulation and test results agree with the theory. Voltage-to-IPI conversion needs significantly less area and power than ADC and is significantly more immune to noise and other problems than using analog voltage/current signals.     

Economic Value of Tree Fruit Production in Jordan Valley from a Virtual Water Perspective

The continuous high demand of water resources for agricultural uses in Jordan is leading to a water crisis. A possible partial solution may be to import food which requires large amounts of water to grow instead of cultivating high water consuming crops. Crops such as banana and citrus cause a huge virtual water loss, which can be reduced by cultivating other less water-demanding crops. This paper focuses on analyzing the economic value of cultivating tree fruit from a virtual water perspective. The virtual water calculations in this study depend on the average rainfall, water quota, and the crops’ water requirements (CWR). The gross profit to the water use ratio showed that banana has the lowest value 0.085 JD/m³, while lemon has the highest value 1.65 JD/m³. The calculations show that the average embedded water in fruits varies from about 470 m³/ton for grapes to about 2,500 m³/ton for dates. Banana and citrus plantations consume about 21 and 71 million cubic meters (MCM) annually, respectively, which represent about 85% of the total water consumption in fruit tree plantation. The virtual water flow estimation embedded in fruits shows that Jordan imports about 77 MCM per year. However it exports about 29 MCM per year. The results were analyzed from an integrated water resources management (IWRM) perspective. The analysis shows that a way to recover some of the water costs involved in, e.g., banana production would be to increase the fertilizer cost by about 10%. This would double the water cost and increase the banana production cost by about 6.8%. Using this alternative could be a way to better manage the huge losses in virtual water involved in banana production in the Jordan Valley.     

A 33 mW 12.5 Gbps BiCMOS transmitter for high speed backplane applications

This paper describes a 12.5 Gbps voltage mode transmitter with a high speed signal conditioning capability. Using a linear equalizer that is followed by a power efficient output stage, the transmitter achieves pre-emphasis at very low power consumption. In measurements, the transmitter can reliably transmit a 12.5 Gbps PRBS7 signal through a lossy 14 in. FR4 stripline commonly used in backplanes. It achieves a peak to peak jitter of 24 ps, a differential eye opening amplitude of 120 mV, and a maximum common mode ripple of 40 mV. The proposed topology consumes 33 mW at-speed power which includes both the output stage and the linear equalizer. It also passes 8KV HBM ESD testing without compromising the high speed capability. The transmitter is fabricated in a 130 nm BiCMOS technology with 100 GHz maximum f_t and packaged in a commercial leadless leadframe package.     

RISE: A general simulation interoperability middleware container

In recent years, new services on the Internet have enabled global cooperation; in particular, the Web has enabled new distributed simulation technology. Much research has been devoted to develop middleware interoperability methods on the Web. However, most existing methods have constraints in the structural rules that are placed on the design of middleware interoperability methods. For example, such constraints make it difficult to enhance interoperability via decoupling systems implementations and design, which is essential in open computing networks, as in the case of the Web. In order to achieve such objectives we present the RISE (RESTful Interoperability Simulation Environment) middleware. This all-purpose WS-based distributed simulation middleware decouples design and implementation while allowing composition scalability and dynamicity. Furthermore, it supports experiment-oriented frameworks and has the ability to put Web 2.0 services in the simulation loop. RISE is the first existing middleware to achieve such objectives, and the first to employ RESTful Web-services. We present the foundations for meeting the above objectives, and the distinct characteristics of RISE from existing Web-based approaches.     

A 2.488–11.2 Gb/s SerDes in 40 nm low-leakage CMOS with multi-protocol compatibility for FPGA applications

This paper presents the design and Silicon verification of a 2.488–11.2 Gbps multi-standard SerDes transceiver in a 40 nm low-leakage CMOS process. The paper explores the architectural and circuit techniques used to meet the stringent requirements of the high-speed SerDes and to mitigate the performance impact of the low-leakage process. A system modeling approach is described, which is used for optimizing the architectural trade-offs. The transceiver makes use of a low-jitter LC phase locked loop to enable high-reliability system design. The design has 420 fs RJ_rms and consumes 30.1 mW/Gbps at 11.2 Gbps.     

Representation,methods, and circuits for time‐based conversion and computation

In this paper, we present an efficient representation of the analog signal using the inter‐pulse interval (IPI) time. Based on this representation, methods and circuits for conversion and computation have been developed. To validate these methods and circuits, a test chip has been fabricated using a 0.35µm mixed‐signal CMOS process. Together, the circuits occupy 59.52 × 10^?3mm² of chip area and consume 8.8 mW of power from a 3.2 V supply. Test results at 10 MHz and simulations results at 100 MHz show good accuracy over ±600mV range. Copyright © 2010 John Wiley & Sons, Ltd.