The segmentation of liver using computed tomography (CT) data has gained a lot of importance in the medical image processing field. In this paper, we present a survey on liver segmentation methods and techniques using CT images, recent methods presented in the literature to obtain liver segmentation are viewed. Generally, liver segmentation methods are divided into two main classes, semi-automatic and fully automatic methods, under each of these two categories, several methods, approaches, related issues and problems will be defined and explained. The evaluation measurements and scoring for the liver segmentation are shown, followed by the comparative study for liver segmentation methods, pros and cons of methods will be accentuated carefully. In this paper, we concluded that automatic liver segmentation using CT images is still an open problem since various weaknesses and drawbacks of the proposed methods can still be addressed.

This paper presents an initial investigation for breast cancer detection using a special mode of bistatic radar system known as Forward Scattering Radar (FSR). The proposed method analyzes the Doppler frequency in the received signal scattered from the tumor for cancer detection and localization. Three systems of architectures were analyzed which determined by the mechanical movement of transmitter or receiver or both. This paper also discusses an initial simulated result by using CST Microwave Studio as a feasibility study of utilizing FSR for breast cancer detection. It is shown that by investigating the unique character of Radar Cross Section (RCS) for breast tissue and tumor of FSR a cancer can be predicted. Electromagnetic model including fatty tissue and a tumor were simulated to obtain RCS parameter and analyzed as well as compared with whose fatty tissue without cancerous lesion to pinpoint the presence of tumor from its FSR signature. The result shows a significant different between these two models in FS RCS.

This paper presents a Dual-sideband Optical Carrier Suppression (DSB-OCS) technique which is used to generate an optical millimeter-wave (mm-wave) signal in radio over fiber (RoF) systems. The proposed system employs a Dual-Electrode Mach-Zehnder Modulator (DE-MZM) and a carrier of 40 GHz mm-wave for data transmission through the RoF systems. Characteristics determining the performance of the system, among which are the modulation index, phase imbalance and dispersion parameters, are included. The performance evaluations of the system show that the mm-wave signal output power follows MZM’s transfer function when the modulation index is raised. Moreover, the generated optical mm-wave signal power is affected by phase imbalance and optical splitting ratio. It is observed that the optical fiber dispersion influences the DSB-OCS system by decreasing the amplitude of the mm-wave and the signal-to-noise ratio (SNR).

In this study, we examined the effect of phase noise on the optical millimeter-wave (mm-wave) signal in a dense wavelength division multiplexing radio-over-fiber (DWDM-RoF) system. A single modulator was used to generate the optical mm-wave signal in the DWDM-RoF system. This paper addresses the impact of phase noise, which results from phase imbalance, on the optical mm-wave signal. To lower the effect of phase noise on the optical mm-wave signal, the phase imbalance should be controlled. The phase imbalance can be controlled and decreased by adjusting the phase at the phase shift (PS). The system performance was analyzed using various parameters such as bit error rate (BER), signal-to-noise ratio (SNR), optical signal to noise ratio (OSNR), and error vector magnitude (EVM). From the results, we found the phase imbalance affected the optical mm-wave signal due to the imbalanced splitting of the signal intensity at the MZM. The phase imbalance impacts the phase noise, which impacts the optical mm-wave signal. The phase noise could be decreased by controlling the phase imbalance at the phase of 5π/12. The best results at the phase of 5π/12 were collected for phase noise at 0.02 degrees.

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Long Term Evolution (LTE) is an emerging 4G wireless access technology. It is showing a lot of promise in field trials and gaining acceptance among the major wireless vendors. The Long Term Evolution (LTE) standard for mobile broadband employs this MIMO technique in its transmission modes which were defined in release 8. The advantage of using MIMO is the improved performance in terms of coverage, spectral efficiency, reduced power consumption and peak throughput in LTE downlink, PDSCH channel can use several MIMO techniques which includes transmit diversity, spatial multiplexing and beamforming. The antenna configuration in transmitting and receiving side may be 212, 214 or 414. However the performance of transmission modes varies with the variation of multipath channel, UE speed and UE location within a cell. So, it is necessary to analyze their performance by considering the above facts. In this paper, the throughput conditions are investigated by changing the UE speed and also changing multipath channel in order to find out which transmission mode is best for which condition.

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The high prevalence of the Internet services in Iraq have led to the emergence of tight and crowded towers Wi-Fi (Wireless Fidelity) services in residential neighborhoods because of the limited extent of coverage of this system. This led to increased cost of subscriber's services due to the multiplicity of mediators, as this system is limited only to cover the fixed places.In this research, we are compare the effectiveness in terms of coverage area (fixed and mobile ), speed downloading data and other matters. This system is WiMAX: (Worldwide Interoperability for Microwave Access).The WiMAX technology is well suited for cities characterized by the construction of a horizontal and a lack of natural heights or artificial (very high vertical buildings). This fully applies to the Iraqi topographical, which will lead to lower the overall costs due to the reduction of the towers and equipment to a very small percentage. For example, Baghdad city will need no more than three towers for full coverage , in other hand technical specifications, lower cost to subscribers due to shorter preparation of mediators , reduced substations located in abundance in residential areas. Research will explain by direct comparison between the two systems including the strengths and weaknesses of both, and their behavior according to the topography of Iraqi cities.