Enhancing Student Learning Using Simulation Programs and Scientific Visualization

A new approach in teaching electromagnetics using multi-media simulation programs was implemented to enhance student learning and hence increase student retention. The fundamental nature of Electromagnetics makes its understanding a necessity in order to comprehend all the other Electrical Engineering topics. The basic Electromagnetics theory and its engineering applications material are all based on highly mathematical equations. Students had difficulty understanding and/or visualizing its abstract topics. This course is presently taught using the latest class technologies and its contents are available on the Internet for out of class access

Plasmonic transmission lines: neural networks modeling and applications

In this thesis, a new model based on Artificial Neural Network (ANN) is used to predict the propagation characteristics of plasmonic nanostrip and coupled nanostrips transmission lines. The trained ANNs are capable of providing the required outputs with good accuracy. The nonlinear mapping performed by the trained ANN is written in the form of closed form expressions for the different characteristics of the lines under investigation. These characteristics include the effective refractive index and the characteristic impedance. The plasmonic coupled nanostrips transmission line is used as a new sensor that that senses variation in the refractive index with accuracy of 106μm (The accuracy is defined as the change in the coupling length divided by the change in the cladding material refractive index). In addition, an optimal new design for polarization rotation based on the coupled nanostrips is introduced and characterized

An Iron Rod Impaling the Axilla with Major Vascular Injury: a Case Report

Background and Objective Impalement injury is an uncommon cause of vascular trauma; however such spectacular injuries are associated with a high mortality rate and need to be managed by a multidisciplinary medical team at tertiary trauma center. The reported literature is scarce and no available well-written guidelines so that the management plan should be individualized and tailored to the situation at hand. The objective of this case study is to update our experience and protocols to maximize the clinical outcome and minimize the fatality rate of such challenging life-threatening events. Methods It is a case report of a 31-year construction worker that sustained an impalement injury when he fell down on an iron rod traversing his left axilla; he was transferred to our hospital with a 90- cm rod in situ. The patient was rapidly resuscitated and investigated preparing him for prompt surgical intervention; the metallic rod was extracted at the theater gently under direct vision with gushing out of blood due to the major vascular injury that was immediately controlled, followed by proper washout and thorough debridement of all devitalized tissues. Then, exploration of the neurovascular bundle at the axilla showed an injury of the axillary vein for which primary repair was successfully performed, but fortunately the axillary artery and brachial plexus were intact. Results: The patient had uneventful postoperative course with no complications and his limb was saved; he is being followed for 14 months up till now. Conclusion Major vascular injuries caused by impalement accidents are rare events; however they are challenging and may be fatal. Our current conclusions and recommendations are deficient and we need more updated research work to improve the outcome and decrease the number of deaths. We can acknowledge the end points which include careful and rapid transportation of the patient to a tertiary trauma centre with the impaled objects in situ that should be extracted only at the theater, proper diagnosis and prompt surgical intervention by a multidisciplinary team

The development of a fiber optics communication network for controlling a Multidegree-Of-Freedom Serpentine Truss

The problem addressed by this report is the large size and heavy weight of the cable bundle, used for controlling a Multidegree-Of-Freedom Serpentine Truss Manipulator arm, which imposes limitations on the manipulator arm maneuverability. This report covers a design of an optical fiber network to replace the existing copper wire network of the Serpentine Truss Manipulator. This report proposes a fiber network design which significantly reduces the bundle size into two phases. The first phase does not require any modifications for the manipulator architecture, while the other requires major modifications. Design philosophy, hardware details and schematic diagrams are presented

Study of atmospheric parameters measurements using MM-wave radar in synergy with LITE-2

The Lidar In-Space Technology Experiment, (LITE), has been developed, designed, and built by NASA Langley Research Center, to be flown on the space shuttle 'Discovery' on September 9, 1994. Lidar, which stands for light detecting and ranging, is a radar system that uses short pulses of laser light instead of radio waves in the case of the common radar. This space-based lidar offers atmospheric measurements of stratospheric and tropospheric aerosols, the planetary boundary layer, cloud top heights, and atmospheric temperature and density in the 10-40 km altitude range. A study is being done on the use, advantages, and limitations of a millimeterwave radar to be utilized in synergy with the Lidar system, for the LITE-2 experiment to be flown on a future space shuttle mission. The lower atmospheric attenuation, compared to infrared and optical frequencies, permits the millimeter-wave signals to penetrate through the clouds and measure multi-layered clouds, cloud thickness, and cloud-base height. These measurements would provide a useful input to radiation computations used in the operational numerical weather prediction models, and for forecasting. High power levels, optimum modulation, data processing, and high antenna gain are used to increase the operating range, while space environment, radar tradeoffs, and power availability are considered. Preliminary, numerical calculations are made, using the specifications of an experimental system constructed at Georgia Tech. The noncoherent 94 GHz millimeter-wave radar system has a pulsed output with peak value of 1 kW. The backscatter cross section of the particles to be measured, that are present in the volume covered by the beam footprint, is also studied

Digital modulation schemes for high speed transmission through low bandwidth lowpass analog links

Existing NTSC (National Television System Committee) standard will be phased out and replaced with HDTV (High Definition Television) standard within the next 10 years. Accordingly, the existing video network system operated by NASA will become obsolete and requires either replacement or modification to accommodate digital transmission. Network replacement is extremely expensive, hence, several digital modulation schemes are investigated in this report to accomplish digital transmission over existing analog links saving NASA from the cost of network replacement. There are two competing transmission systems available for HDTV transmission over limited bandwidth channels. The cost and performance of the two competing schemes are remarkably similar. However, the input data rate in such a case is limited to 40 Mbit/s. Transmission of higher data rates is possible using simple signal processing techniques. On the other hand, a third transmission system, multilevel pulse amplitude modulation (M-PAM) is proposed. M-PAM is the first stage of the well known M-VSB. This M-PAM scheme is much simpler and uses the channel more efficiently. The three schemes are compared and preliminary conclusions were made. Despite of several similarities, each modulation scheme has it unique merits. To determine the suitability of each scheme, more investigations and laboratory tests for all schemes are needed

Androgen Receptor-Target Genes in African American Prostate Cancer Disparities

The incidence and mortality rates of prostate cancer (PCa) are higher in African American (AA) compared to Caucasian American (CA) men. To elucidate the molecular mechanisms underlying PCa disparities, we employed an integrative approach combining gene expression profiling and pathway and promoter analyses to investigate differential transcriptomes and deregulated signaling pathways in AA versus CA cancers. A comparison of AA and CA PCa specimens identified 1,188 differentially expressed genes. Interestingly, these transcriptional differences were overrepresented in signaling pathways that converged on the androgen receptor (AR), suggesting that the AR may be a unifying oncogenic theme in AA PCa. Gene promoter analysis revealed that 382 out of 1,188 genes contained cis-acting AR-binding sequences. Chromatin immunoprecipitation confirmed STAT1, RHOA, ITGB5, MAPKAPK2, CSNK2A,1 and PIK3CB genes as novel AR targets in PCa disparities. Moreover, functional screens revealed that androgen-stimulated AR binding and upregulation of RHOA, ITGB5, and PIK3CB genes were associated with increased invasive activity of AA PCa cells, as siRNA-mediated knockdown of each gene caused a loss of androgen-stimulated invasion. In summation, our findings demonstrate that transcriptional changes have preferentially occurred in multiple signaling pathways converging (“transcriptional convergence”) on AR signaling, thereby contributing to AR-target gene activation and PCa aggressiveness in AAs