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There is little empirical data in the published literature on occupant thermal comfort in buildings from the Modern Movement in architecture. We present a field survey of occupant thermal comfort and indoor environmental conditions in Mies van der Rohe’s modern S. R. Crown Hall (1956) on the campus of Illinois Institute of Technology in Chicago, IL. Surveys were deployed to 557 student participants on four separate days, including two days in the cooling season and two days in the heating season, to assess their perceptions of thermal comfort throughout the space. Indoor air temperature, relative humidity and mean radiant temperature were measured concurrently in several locations throughout the space. Occupants reported high levels of dissatisfaction with comfort in the space (percent dissatisfied ranging 37%–54%), with somewhat counterintuitive results for this building type. Overcooling was apparent during warm weather and a combination of both over- and under-heating occurred during cold weather, contrary to what was expected in this building with a high thermal transmittance enclosure. There was also high spatial variability in comfort responses and measured indoor environmental conditions. Findings highlight the need to develop contextual approaches to meeting occupant comfort needs in this building while preserving architectural aesthetics/intent.

In the present work, the analysis and design of a line fed two-layers coupled rectangular patch antenna is presented. The return loss, the input impedance, and the radiation pattern of the proposed structure are determined using the finite difference time-domain (FDTD) method. The effect of changing the air gap layer thickness between the two layers of that antenna is studied. The results obtained by the FDTD method are found to be in good agreement with the published data. Also it is found that as the air gap layer thickness is increased the 10-dB return loss bandwidth is decreased while the 3-dB beamwidth of that antenna is increased.

A new technique for designing wideband microstrip antenna on the basis of the recently proposed substrate integrated waveguide technology is proposed. In this technique, log-periodic slot array antenna on substrate integrated waveguide with different substrate thicknesses and different terminations is presented. The proposed antenna was designed using Ansoft HFSS simulation software package. The antenna is able to achieve an impedance bandwidth of 41 % for a return loss of less than -10 dB.

In this paper, a bi-directional UWB MIMO antenna is presented and investigated for superior UWB MIMO performance. The MIMO antenna elements are proved to have a typical impedance matching and direc...

Background: Fetuin-A is a liver-derived plasma protein, mediates the formation and stabilization of calciprotein particles formation, ensures mineral solubilization, thus preventing pathological calcification, also it promotes insulin resistance. Objective: To study the role of fetuin A as a marker for early diabetic nephropathy in type 2 diabetes mellitus. Subjects and Methods: Cross sectional study including 30 diabetic patients without microalbuminuria (group I), 30 diabetic patients with microalbuminuria (Group II) and age and sex matched 30 healthy subjects served as a control group. All patients and control subjects were thoroughly examined clinically. Fasting and post prandial blood sugar, HbA1c, renal function tests, lipid profile, creatinine clearance, albumin/creatinine ratio and serum fetuin A by ELISA were investigated. Results: Serum Fetuin A increased in diabetic nephropathy patients without microabuminuria compared to those with microabuminuria. Significant negative correlation was found between serum Fetuin A and albumin/creatinine ratio in diabetic patients with and without microalbuminuria. Cut off value of serum fetuin A was >294.2 ug/dl with sensitivity of 93.3% ,specificity 93% , positive predictive value 92.7%, negative predictive value 93.8% and diagnostic accuracy 91.6%. Conclusion: Serum fetuin A can be used as an early marker for diabetic nephropathy before development of microalbuminuria in patients with type 2 diabetes mellitus.

A rectangular microstrip patch (RMSP) antenna is designed to be used in a two-element Multi-Input Multi-Output (MIMO) antennas at which they operate at 5.8 GHz. The two antennas are positioned opposite to each other with a separation of 10 mm (0.2 λ0) from their radiating edges. A novel uni-conductor electromagnetic bandgap (UC-EBG) periodic cells are introduced in this paper as effective barriers for surface waves compared to the conventional UC-EBG. Each unit cell has a compact size area 7.3 × 5.8 mm2 where it is 20% more compact than the conventional cell. Two of the proposed modified EBG periodic cells are placed in-between the two antennas causing an excellent reduction in the coupled power of 46 dB. This strong isolation definitely enhances the performance of antennas in MIMO communication systems, where 0.0001 and 0.03 values for correlation coefficient have obtained from S-parameters and far-field information, respectively, due to this strong isolation.

In this paper, an efficient technique proposed for surface wave filtering in radar array antennas. The filtering reduced the correlation between high directive TX/RX array antennas. The filtering has been done using a small defected ground filter that achieves more than 20 dB isolation between the two antennas with a very close separation between the two antennas (less than 0.06 λ0). The presented results confirm the advantage of the applied technique in reducing the correlation coefficient between the two antennas to less than 0.005. The results demonstrate that 99.68% of coupled power can be reduced. The integrated isolated radar array antennas have been studied theoretically, simulated using electromagnetic simulation, and measured experimentally.

This paper presents a new overlapped coilgun configuration to launch medium weight projectiles. The proposed configuration consists of a two-stage coilgun with overlapped coil covers with spacing between them. The theoretical operation of a multi-stage coilgun is introduced, and a transient simulation was conducted for projectile motion through the launcher by using a commercial transient finite element software, ANSOFT MAXWELL. The excitation circuit design for each coilgun is reported, and the results indicate that the overlapped configuration increased the exit velocity relative to a non-overlapped configuration. Different configurations in terms of the optimum length and switching time were attempted for the proposed structure, and all of these cases exhibited an increase in the exit velocity. The exit velocity tends to increase by 27.2% relative to that of a non-overlapped coilgun of the same length.

A modified uni-planar compact electromagnetic bandgap structure (UC-EBG) is proposed to suppress the surface waves excited in between two rectangular microstrip patch antennas (RMSP). The antennas are functioning at WLAN applications at 5.8 GHz. The unit cell dimensions of the proposed modified UC-EBG are 7.3 mm×5.8 mm (20 % miniaturization of conventional U C- EBG). The patches are placed apart by 10 mm (0.2 λ0) edge to edge. Thanks to the modified U C- EBG cell, the mutual coupling between the two patches is improved by 45 dB and 2.5 dB compared to cases without using EBG and using conventional UC-EBG, respectively.

A big problem that encounters businesses, especially telecommunications business is ‘customer churn’ this occurs when a customer decides to leave a company's landline business for another cable competitor. Therefore, our aim beyond this study to build a model that will predict churn customer through defining the customer's precise behaviors and attributes. We will use data mining techniques such as clustering, classification and association rule. The accuracy and preciseness of the technique used is so essential to the success of any retention attempting. After all, if the company is not aware of a customer who is about to leave their business; no proper action can be taken by that company towards that customer.

This paper presents the investigation on electromagnetic launch for single stage coilgun. The proposed coilgun and its excitation circuit were designed for launching small objects few meters. A transient simulation for the projectile motion through the launcher was done using transient finite element commercial software ANSYS MAXWELL. Also a comparative comparison between different parameters is introduced including the effect of number of turns, voltage, induced current and length of coil on the exit velocity of projectile while leaving the barrel. Detailed studied cases have been investigated. The results confirm a direct proportional relation between the velocity of projectile and number of turns, voltage and induced current in coil while confirming an inverse proportional relation with the length of coil.

In this paper, a defected ground structure is employed in a transceiver array antenna to reduce coupling between the two antennas. The two arrays for transmitting antenna and receiving antennas are implemented on the same substrate with close separation. The coupling reduction principles for each transceiver MIMO antenna are explained. The MIMO antenna performance was examined using electromagnetic full wave. Results confirm that both coupling reduction reached better than15 dB with very close spacing; 2 mm spacing which is less than 0.05 λ0.

This paper presents the application of an antenna beamforimging using a modified and new blind adaptive algorithm for nulling of interference wideband signals. An adaptive linear array antenna is employed. The theoretical design principle of the proposed algorithm is presented. The results confirm that the proposed algorithm achieves better antenna array beamformation nulling compared to conventional algorithms. The proposed array has 6 dB interference signals nulling better compared to conventional least mean square algorithm and does not need a reference signal.

Developing a space system is a challenge which includes risk that increases with the lack of practical experience especially for a new player in space industry. A concurrent design facility (CDF) with especially tailored work stations can lower the risk of lack of experience through increasing the team interaction as additive experience and decrease over design budgets generated by designers as a result of over protective measures which leads to the infeasibility of the project. It has been demonstrated that CDF approach has proved to minimize cost and time of conceptual design, increasing possibility of studying all possible technical resolutions and exploring different architectures to find the most appropriate architecture for each mission meeting time, cost and risk constrains and also satisfying the customer who already participates during conceptual design phase. Establishing concurrent design facility (CDF) for developing countries newly introduced to space industry has great importance. With the proper organizational assembly and especially tailored workstations developing countries would have the chance to start accomplishing strong steps in designing a feasible space missions. In this paper a survey of existing concurrent design facilities (CDF) and the modifications conducted and recommended to achieve optimum risk and cost to make the facility a valuable asset for emerging countries is presented.

a new type of dielectric resonator reflectarray composed of 529 elements covering an area of 276 x 276 cm 2 is constructed. The unit cell consists of squared DRA supported on a strip with variable slot length, a dielectric layer and a conducting ground plane. The full phase of 360 degree of the array elements can be obtained by superposition two slot-strip sizes. Two types of feeding were analyzed, the first is center fed reflectarray while the second is offset feed to reduce the feeder blockage and as a result the antenna efficiency is improved. The antenna has 10% bandwidth for 1 dB gain variation is obviously wider than that of conventional reflectarray antenna while the offset fed reflectarray provide better far field pattern with back lobes reduction by -5 dB and side lobe by -2 dB. A rectangular X- band pyramidal horn was used in both reflectarrays which have 23 x 23 elements of with cells separation of 12 mm that less than 15 mm (lambda/2) for avoiding grating lobes. CST microwave studio © (finite integral technique) package is applied and compared with microstripes © package (transmission line technique) with good agreements between them. The mutual coupling between the feeding horn and the elements of the reflectarray are considered. At 10 GHz, the antenna provides a 3-dB beamwidth of 6 degree with a gain of 28 dB. The antenna bandwidth within 1dB gain variation is found to be 13% and aperture efficiency of 59%.

A reflectarray antenna consists of elements of rectangular dielectric resonator (DRA) with slot loading of different lengths is proposed for bandwidth enhancement. Two DRA sizes an two slot widths are available to tune the phase of each element in the reflectarray so that a full 360 degrees phase shifts can be achieved by superposition. Two structures are presented in that paper. The first is center fed reflectarray while the second is offset fed for decreasing the feeder blockage. The antenna has 10% bandwidth for 1 dB gain variation is obviously wider than that of conventional reflectarray antenna while the offset fed reflectarray provide better far field pattern with back lobes reduction by -5 dB and side lobe by -2 dB. A pyramidal X-band horn was used in both reflectarrays which have 23 x 23 elements of with cells separation of 12 mm that less than 15 mm (lambda/2) for avoiding grating lobes. The analyses are carried out using the finite integration technique (FIT) and the transmission line method (TLM) with good agreements between them.

Two dielectric resonator antennas are discussed to generate circularly polarized waves in a reflectarray anten- na . In this case, two models are discussed here, one is DRA supported on cross slot, while the second is aperture coupled DRA supported on cross strip line coupled to DRA by cross slot. The verification of reflection coefficient phase of cell is satisfied by CST microwave studio and HFSS package. A complete array of 15 x 15 fed by a circular horn tilted by 45 de- gree was designed and simulated at X-band by full wave package. The simulated results show that the obtained 1.5-dB gain bandwidth and 3-dB axial ratio bandwidth of the reflectarray with aperture coupled DRA can reach as large as 25% and 12.5%.

The design and simplifled analysis of a compact and wide band (16%) negative permittivity complementary split ring resonator metamaterial is introduced. The proposed metamaterial component was applied to reduce the size of the feeding line fllter of microstrip patch antenna for the sake of higher order harmonic suppression. The reduction has been done using only one element of complementary split ring resonator, while maintaining the antenna's performance. Simplifled theoretical study and design of the proposed circuits has been presented. Moreover, experimental results have been done for validation and conformation purpose. Results conflrm that almost 95% of the antenna noise harmonics power has been removed.

A preliminary design and implementation of a Telemetry and Telecommand (T&Tc) subsystem is presented by using Commercial Off The Shelf (COTS) modules. Telemetry data are collected, stored, and then transmitted to the Ground Station (GS). Commands are executed in both autonomous and GS controlling modes. Commands are executed on the On Board Computer (OBC) according to prepared scheduled commands and patch files. Updated patch files can be loaded from the Ground Control Center (GCC) to the OBC.

In this paper, we introduce detailed analysis of electromagnetic wave propagation along a planar ferrite coplanar waveguide transmission line. The analysis was done using the electromagnetic full wave of CPW transmission lines implemented on ferrite substrate. All the possible excitation directions of the applied DC magnetic bias were studied. The analytical study was verified using full wave simulations of electromagnetic waves propagation along different types of ferrite coplanar waveguide. The simulation results confirmed the propagation characteristics derived in the analytical study.

The total cost of the large arrays can be solved by dividing the array into contiguous subarrays with amplitude and time delay devices at subarray level. This cause appearance of grating lobes when the beam has been steered to small angle away from broadside named grating lobes due to uniform subarrays. These grating lobes caused by the periodicity and the larger spacing between subarrays. If there is a need to steer the main beam at angle that will be small (limited scan), some methods are used to reduce these grating lobes. These methods will be optimized using genetic algorithm implemented using MATLAB. Two approaches used to disrupt the periodicity in the array, so reduction of the grating lobes can be achieved. Three parameters are optimized simultaneously, the amplitude weighting at the subarray ports; the number of elements per subarray and the spacing between elements. The results show that the two approaches reduce the grating lobes upto -9.8 dB for the first approach and -14.6 dB for the second approach, when steered over small-scan angles, up to 15° from broadside, after this range grating lobe will appears again and cannot be reduced.

Split Ring Resonators (SRRs) are widely used to design metamaterial structures. These structures when excited by suitable electromagnetic fields have resonance behavior and show unusual properties near the resonance frequency region. In this paper, Transmission Line Matrix Method (TLM) is used as a new, efficient and accurate time domain methodusing the 3D Symmetrical Condensed Node (SCN) to study, design and simulate SRRs as a metamaterial structure. This approach is done by using a modified written FORTRAN code. Results of TLM verified with those obtained by measured data of the fabricated structure and comparison showed great matching between results.

The development of phased array antennas is challenged by the reduction of scan volume due to the appearance of grating lobes. The grating lobes appear in visible space as the spacing between elements be greater than half wavelength. The need for enlarging the spacing between elements is important either for reduction of mutual coupling or filling specific aperture size with small number of antenna elements. These grating lobes should be reduced or eliminated for enlarging the scan space. Nonuniform spacing between elements is an effective method for reduction of grating lobes as it breaks the periodicity of the array which is the reason of grating lobes. This method will be optimized using genetic algorithmimplemented using MATLAB. The reduction is -9.7 dB for 8-elements and -12.4 dB for 16- elements at 60° scan angle.

The new bread wheat cultivar Sids 13 has been developed by Wheat Research Department, Field Crops Research Institute, Agriculture Research Center, Egypt and selected from one of the advanced lines among ICARDA collections grown in wheat breeding program at Sids Agricultural Research Station. The grain yield of the new cultivar Sids 13 was evaluated through 66 experiments at two different levels of yield trials (11 preliminary and 55 advanced yield trials) in the three successive seasons 2004/2005, 2005/2006 and 2006/2007, respectively. The obtained results proved the superiority of the new cultivar Sids 13 as compared to the local commercial cultivars, Giza 168, Sakha 93 and Gemmiza 9 in the main five regions of Egypt, i.e. North Delta, South Delta, Middle Egypt, Upper Egypt and Out Valley. Moreover, stability parameters for grain yield cleared that the newly bread wheat cultivar Sids 13 has better stability parameters in both South Delta and Upper Egypt regions and could be recommended for planting in those regions. Also, the results of rust diseases reactions proved that Sids 13 has high resistance to all tested pathotypes of the three rust diseases under local conditions.

A rectangular planar array antenna synthesis technique based on Genetic Algorithmoptimization is used to achieve sufficient link margin for low earth orbit (LEO) satellitesantenna, by adjusting the antenna gain.A genetic algorithm (GA) is used to optimize the array excitation. Thinning [1] ofelements is used with different excitation techniques.A phased array antenna with rectangular aperture and cos1.5 􀈙 elements power pattern isassumed.

A rectangular planar array antenna design using thinning technique and GeneticAlgorithm (GA) optimization technique are used to minimize the gain variation for LowEarth Orbit (LEO) satellites antenna. This design controls the feeding amplitude throughthinning without requirements to control the phases which yields to simplify the feedingnetwork.Two antenna elements are proposed, cos1.5 􀈙 radiation pattern element and therectangular patch element.A simple genetic algorithm optimizer is used to get the optimum excited elements onthe array.