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Despite the recent progress on Ecological Vulnerability studies by developing index models, similar studies on the coastal areas are still rare. Pingtan’s main island of Fujian Province in China an...

This investigation aims to establish a system to test the identification of shoreline changes along the coast of Hurghada. Besides, the Digital Shoreline Analysis System (DSAS) studies the shorelin...

The impacts of climate change on the Nile River and Grand Ethiopian Renaissance Dam (GERD) along with the increased water demand downstream suggest an urgent need for more efficient management of the reservoir system that is well-informed by accurate modeling and optimization of the reservoir operation. This study provides an updated water balance model for Aswan High Dam Reservoir, which was validated using combined heterogeneous sources of information, including in situ gauge data, bias-corrected reanalyzed data, and remote sensing information. To investigate the future challenges, the spatial distribution of the annual/seasonal Aswan High Dam Reservoir surface air temperature trends over the period from 1979 to 2018 was studied. An increase of around 0.48 °C per decade in average annual temperature was detected, a trend that is expected to continue until 2100. Moreover, a set of machine learning models were developed and utilized to bias-correct the reanalyzed inflow and outflow data available for Aswan High Dam Reservoir. Finally, a policy tree optimization model was developed to inform the decision-making process and operation of the reservoir system. Results from the historical test simulations show that including reliable inflow data, accurate estimation of evaporation losses, and including new regulations and added projects, such as the Toshka Project, greatly affect the simulation results and guide managers through how the reservoir system should be operated in the future.

Aim: The aim of this study was to assess the effect of using collagen sponge combined with injectable platelet rich fibrin in post extraction socket. Subjects and Methods: 26 patients selected. All patients had a treatment plan for extraction of non-restorable single rooted maxillary tooth. Group A (control): Extraction socket was left for normal healing (blood clot), just patient presses on the gauze for promoting hemostasis. Group B (study): Extraction socket was filled with combination of collagen sponge and injectable platelet rich fibrin. In the present study, the following measurements were recorded: Width of alveolar ridge. Vertical measurements. Bone density. Bone volume. Results: Post-operative Study group showed a higher average width (5.28) of alveolar ridge than control group (3.41). Post-operative; study group showed a high volume (100.7) than control group (48.21). Post-operative; Study group showed a higher bone density (443.0) than control group (192.2). Post-operative; Study group showed a higher bone density GV (633.0) than control group (275.2).Conclusion: The use of collagen sponge with autologous I-PRF in the present study, significantly minimized ridge resorption in all dimensions.

This paper introduces a low-power wireless RF receiver for the wireless sensor network. The receiver has improved linearity with incorporated current-mode circuits and high-selectivity filtering. The receiver operates at the 900-MHz industrial, scientific, and medical band and is implemented in 130-nm CMOS technology. The receiver has a frequency multiplication mixer, which uses a 300-MHz clock from a local oscillator (LO). The LO is implemented using vertical delay cells to reduce power consumption. The receiver conversion gain is 40 dB and the receiver noise figure is 14 dB. The receiver’s input third-order intercept point (IIP3) is −6 dBm and the total power consumption is 1.16 mW.

The Nile River Basin (NRB) is a typical example of a transboundary river basin that provides crucial resource for the economy and politics of eleven countries in northeastern Africa. Understanding the reservoir operation in the NRB is crucial to cope with challenges imposed by intense population growth, recurring drought, climate change and increasing competition for water. Data availability to monitor reservoir operation is predominantly an issue, particularly in transboundary basins crossing developing nations, as in the NRB. Such data challenge has been relatively overcome by remote sensing observations that are made available at high spatial and temporal resolutions. Our study implemented a Multi-Sensor Satellite (MSS) approach to understand the reservoir operation in the NRB with the focus on the joint operation of High Aswan Dam (HAD) and Toshka Lakes, located in the south western part of HAD. The MSS approach integrates a suite of satellite observations including Landsat, Sentinel-2, MODIS, satellite altimetry data, and GRACE. The MSS data, along with hydrological model outputs, are used in a water balance model to derive the operation of HAD reservoir and Toshka Lakes. Our study showed that MSS approach has a reasonable skill when modeling the Toshka inflow (i.e., HAD spillway outflow) with an average relative bias -28.5% (averaged for the period 1998-2002) and -6.9% (averaged for the two years 2001-2002). Overall, the MSS approach can potentially assist water managers and dam operators to make more informed decisions in the NRB, especially with the construction of new dams in the upstream countries (e.g., Grand Ethiopian Renaissance Dam; GERD).

El-Burullus coastal zone suffers instability due to the construction of protective measures. This study aims to examine changes in land use/land cover and to detect shoreline changes using remote sensing and GIS tools. Firstly, monitoring changes occurs in land use/land cover carried out using Landsat and SPOT images over the years (1984, 2001, 2012 and 2017). The results of the change detection revealed that the lake area has been decreased by 7.23% due to the continuous increase in the urban area around the lake. Fish ponds incredibly increased by a huge percentage of 432.19%. The agricultural area has increased slightly to 7.94%. On the other hand, it is concluded that the maximum rate during the period (2001–2012) is 46.7 m/year due to the construction of hard protection on the west side which resulted in downdrift erosion (eastern side) with a maximum rate of 32 m/year. It is found that the maximum erosion rate was 38.3 m/year on the eastern side between 2012 and 2017, while the maximum erosion rate on the western side was 48.65 m/year.

The Gulf of Suez, Northern Islands protected area, and Hurghada zone are experiencing mega developments in all sectors including tourism, industry, and logistics. The need for moderately accurate near-shore hydrodynamic models is increasing to support the sustainable development of this oceanic area. This can be accomplished by following a nesting approach including the downscaling of global atmospheric and oceanic models into local models using higher resolution datasets. This work aims to present the development of a one-way coupling between atmospheric and hydrodynamic models for the Gulf of Suez (GOS) to understand the local oceanic characteristics and processes. The Regional Climate Model system (RegCM4) is used to simulate moderate resolution atmospheric features and its results are used to force a local dedicated application of Delft3D model. The results indicate that the predicted water level, water temperature, and evaporation accurately follow in situ measurements, remotely sensed data, and re-analysis data. The results suggest that the annual sea surface temperature is averaged at 23 °C, while the annual average of evaporation rates equals 8.02 mm/day. The study suggests that the water level displays a marked seasonal and spatial variation. Moreover, the water balance in the Gulf of Suez was controlled by the difference between inflows and outflows through the Straits of Gubal and by the net precipitation. In addition, the water balance indicated a net loss of approximately 3.9 × 10−3 m of water during 2013. Moreover, the exchange through the Straits of Gubal showed a two-way exchange with a net inflow of 0.0007 Sv, where the outflow dominated in the surface layer along the western coast and the inflow dominated in the lower layers along the middle of the Straits. To conclude, the one-way coupling modeling technique proved to be a reliable tool for studying local features of the GOS region.

Wireless transmitters (Tx) targeting Internet-of-things (IoT) applications impose tough end-to-end efficiency requirements. The frequency synthesis problem is usually solved by incorporating a variant of the phase-locked loop. However, power-hungry dividers and large loop time constants hurt the aggregated Tx power consumption and produce systems with slow start-up and turnaround times, particularly when operating at low output power. This paper demonstrates an agile ultralow power and energy-efficient transmitter architecture for IoT applications to address these concerns. The Tx leverages the characteristics of the wideband frequency-shift keying modulation and uses an openloop ring oscillator based on a vertical delay cell as its local oscillator (LO) generator. When followed by an edge-combiner-type power amplifier, the required LO operating frequency drops to one-third of the RF frequency, which further reduces the Tx power consumption. Moreover, LO frequency correction is achieved through a digitally assisted scheme with specially designed delay cells for fast frequency calibration. The Tx was fabricated in 0.18- $\mu \text {m}$ CMOS technology and occupies an active area of 0.112 mm2. The experimental results show a Tx energy efficiency of 0.2 nJ/b for a 3-Mb/s data rate and a normalized energy efficiency of 3.1 nJ/b $\cdot $ mW when operating at a maximum output power of −10 dBm.

The coastline of the Nile Delta extends between Alexandria and Port Said and spans approximately 240 km. It experienced accelerated erosion since the construction of Aswan High Dam (AHD) where more than 1.2 billion EGP were spent to mitigate the imbalance in sediment transport patterns as AHD blocks most of the sediments reaching the Mediterranean coast. The current study investigates various combinations of interventions to mitigate the complex situation around natural and artificial tidal inlets namely Rosetta promontory and El-Burullus fishing harbor inlet. After various previous interventions in both sites, the problem of structures stability, inlets closure, and erosion in the nearby beaches still exists. The study will utilize already developed, calibrated and field validated morphodynamic models for the two areas of interest. Out of the past and present tested scenarios, the study comes up with the optimum combination of interventions at the two inlets. For Rosetta promontory, the third scenario (one-kilometer jetty in the western direction, a 0.4 kilometer one at the eastern direction, another three groins at the eastern direction, and two groins at the western direction) has the least net sedimentation volume at the inlet (2206.58 m3) and the least change in depth at the critical sections. On the other hand, the simulations indicated that SC3 (extension (90 m) of west jetty + 5 east 200 m groins + 2 west groins (200 m)) produced ideal results in terms of the El-Burullus harbor entrance siltation, the erosion in front of seawall and the accretion at the west of breakwater; However, it caused some slight erosion at the shoreline west of the breakwater. The successful concluded results of this study could be adopted with appropriate modifications for other Deltas worldwide.

Summary Sea surface temperature (SST) and surface wind (SW) are considered the most important components in air–sea interactions. This study examines the relationships between SST, SW and various oceanic variables in the northern Red Sea (NRS) during the period of 2000–2014. The current study is the first attempt to identify the SST fronts and their relationship with the dominant circulation patterns. SST fronts are mapped using the Cayula and Cornillon algorithms. The analysis is performed with available remote sensing and reanalyzed data together with 1/12° HYbrid Coordinate Ocean Model (HYCOM) outputs. Seasonal-trend decomposition procedure based on loess (STL) is applied for trend analysis, and Principal Component Analysis (PCA) is run for the atmospheric parameters. The SST, SW speed and Chlorophyll- a (Chl- a ) changes show insignificant trends during the period of 2000–2014. Meridional SST fronts are more significant during the month of January, and fronts that are perpendicular to the sea's axis occur from February to May. Distinct monthly and spatial variations are present in all the examined parameters, although these variations are less pronounced for the wind direction. The SST is mainly controlled by the air temperature and sea level pressure. Significant correlations exist between the SST and the studied parameters (alongshore wind stress rather than the cross-shore wind stress, surface circulation, MLD, and Chl -a ). Surface winds generally flow southeastward parallel to the Red Sea's axis explaining that alongshore wind stress is highly correlated with the studied parameters.

This brief introduces a successive approximation time-to-digital converter based on a novel algorithm denoted as successive approximation register with continuous disassembly (SAR-CD). The main advantage of the proposed SAR-CD algorithm is that it moves the conditioning between the evaluated bits to the digital domain, after all the bits are evaluated. Simulation results show promising enhancements in power consumption compared with the state-of-the-art designs. A full 10-bit architecture is introduced using 65-nm CMOS technology as a case study with simulation power consumption of 2.8 mW at a sampling rate of 29.4 Msample/s from 1-V power supply with an effective number of bits value of 8.63 bits and a maximum differential nonlinearity of 1 least significant bit.

This paper presents a built-in input matching technique capable of handling a wide variation of multi-array thermoelectric generator (TEG) impedances ranging two decades, from 10 s to 1000 s of ohms. Maximum power point tracking (MPPT) control for a boost converter (BC) is introduced. The analytical expressions derived offer insight on the manner in which MPPT interacts with a BC to achieve best performance. The BC operates in a discontinuous conduction mode under pulse frequency modulation to minimize power consumption and maximize efficiency for light loads. Losses are minimized by implementing a pseudo-zero current switching control via the PMOS switch on/off time, and the output voltage is set using a global clocked comparator. A prototype was fabricated in 0.5 μm CMOS where efficiency measurements showed a maximum value of 61.15% for an RTEG = 33.33 Ω, and quiescent power consumption was 1 μW.

Background: Diabetes mellitus (DM) is the most prevalent metabolic disease worldwide and is the most potent risk factor for coronary artery disease (CAD). Consequently, finding a clue to diagnose the presence of CAD as early as possible in diabetic patients is very important. Micro albuminuria is a strong and independent indicator of increased cardiovascular risk among individuals with and without diabetes. The aim of this study was to find any correlation between the degree of albuminuria and the severity of CAD in patients with type 2 DM. Methods: This was a cross sectional study that included 86 patients with type 2 DM whom underwent elective coronary angiography for suspected coronary artery disease in Mansoura Specialized Medical Hospital from March 2014 till March 2015. Albumin creatinine ratio was determined for all patients and severity of CAD was assessed using the SYNTAX score. Results: The patients were classified into 3 groups based on levels of urinary albumin creatinine ratio (ACR); group 1 consisted of patients with ACR 300 mg/gm (22 patients). Age ranged between 41 and 70 years with mean age 58.37 ± 7.20 years, sex distribution was 48 males (55.8%) and 38 females (44.2%). The SYNTAX score and ACR were significantly positively correlated (p

Nowadays, brain scientific research progress depends on signal compression at high spatial resolutions, for efficient storage and low-rate transmission through wireless connection to outside world. So that neural data compression at the implant site is necessary in order to conform with the wireless rates restrictions. In this paper, the high spatial correlation is utilized to increase the data compression ratio. Then we investigate and compare three different proposed low-power image compression algorithms based on discrete cosine transform (DCT) and discrete wavelet transform (DWT) to provide the best trade-off between hardware complexity and compression performance. Hence, we conclude that Adaptive 2D-DWT algorithm is a promising solution for low-power implantable devices.

The Nile Delta and its coastal zone are populated regions in Egypt and contain a variety of development activities. Those human activities which provide income and source of life to many also generate constraints to Nile Delta region. This introductory chapter presents a brief biography of the Nile Delta and presents a comprehensive and concise summary of recent research related to challenges in Nile Delta regions. In addition, possible opportunities are included. Five main themes of research, namely, land use challenge, coastal erosion, potential impacts of sea level rise (SLR), water quality deterioration, and seawater intrusion, are reviewed. Also, the chapter summarizes some suggested/proposed and/or implemented adaptation and/or mitigation acts for each challenge. The article concluded that further integrated research based on solid reliable field databases is urgently needed.

This paper introduces a new algorithm and circuit design of Time-to-Digital Converter(TDC) with modified Successive Approximation Register(SAR) algorithm. This design enables continuous pulse disassemble. The input pulse is absolutely compared to pulses of widths proportional to Vfs/2, Vfs/4‥Vfs/N, and each bit is evaluated independent of the previous bit result. Then bits correction is applied after the sample evaluation. A 4bit case study circuit is realized using TSMC CMOS 65nm design technology. The design demonstrated 3.67 Effective Number Of Bits (ENOB) for a sampling frequency of 666 MS\s.

Summary In this paper, a digitally controlled current conveyo(DCCC) is presented. The proposed DCCC is based on rail-to-rail folded cascode implementation with a current division network (CDN). The CDN is used to provide control on the current gain of the DCCC. The CDN uses a novel current division technique based on differential pairs. The proposed DCCC can operate from ±1.5 V supply voltages. Applications of the proposed DCCC such as variable gain amplifiers (VGA) and digitally tunedfilters have been investigated. PSpice simulations based on the AMI 1.2 µm N-well level 3 parameters are in agreement with the presented work.

El-Burullus Lake is affected by increasing and extensive human activities, rapid social-economic development and the construction of fish ponds nearby. This has significantly impacted the health of the lake eco-system. On the foundation of the two-dimensional depth averaged hydrodynamic model, distributions of the salinity, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and Ammonium (NH4) were modeled. The heat flux model was also utilized to enhance the accuracy of the calculations in the water quality modeling stage. The calibration and the verification of this model were based on spatially distributed water quality measurements during the period 2010-2011. The correlation coefficients between measured and simulated salinity was found to be 0.79 in January 2011 and 0.84 in August 2010 with a mean errors of 1.3407 and 2.0727 ppt in August 2010 and January 2011 respectively. The results generally agree with the observations, but this indicates that more measurements are needed to verify the predictability of the simulations. In addition, Delft-3D model has been applied in evaluating the feasibility of adding a new artificial inlet or diversion of some drains. The model proved to be an effective tool for the water dynamics, water quality simulation and evaluating different scenarios of such shallow Lake.

In this paper, a novel fully differential second-generation current conveyor (FDCCII) is presented. The proposed block is useful in mixed-mode applications where fully differential signal processing is required. Furthermore, the FDCCII can be used to realize MOSFET-C filters. The circuit has a bandwidth of about 10 MHz under heavy capacitive loads and can operate from low supply voltages down to /spl plusmn/1.5 V.