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BackgroundIn multiple sclerosis (MS), even in the presence of clinical brainstem symptoms, the brainstem does not always show gross lesions on magnetic resonance imaging (MRI). However, MS may impair vestibular-evoked myogenic potential (VEMP) responses.Material and methodsThis study included 70 participants, 40 who were MS patients and 30 healthy adult volunteers as controls. All participants were subjected to history taking, otological examination, basic audiological evaluation, bedside examination of the dizzy patient, cervical VEMP (cVEMP), and ocular VEMP (oVEMP).ResultsOf the 40 MS patients, 37.5% had abnormal cVEMP and 67.5% had abnormal oVEMP. Some 23% of the 21 MS patients without brainstemlesions on MRI had abnormal cVEMP and oVEMP, including 69% of those who had vertigo. MS patients with brainstem lesions on MRI had significantly greater oVEMP latency than patients without similar MRI findings.ConclusionsMS patients showed dysfunction in the vestibulo-ocular and vestibulo-spinal reflexes. This dysfunction is reflected in impaired oVEMP and cVEMP respectively despite the absence of structural brainstem abnormalities. Thus, VEMP, especially oVEMP, can be used as an early indicator of brainstem involvement in MS before radiological signs appear on MRI.

BackgroundIn migraine, there is no anatomical correlate of vertigo and no structural abnormality is evident in conventional imaging. Cervical vestibular-evoked myogenic potential (cVEMP) is an uncrossed inhibitory vestibulo-spinal reflex (VSR), while ocular VEMP (oVEMP) represents a crossed excitatory vestibulo-ocular reflex (VOR).ObjectiveThis study aims at functional evaluation of the findings of cVEMP and oVEMP in migraine patients.Material and methodsThis was a cross-sectional case-control study that included 20 migraine patients as the case group and 30 healthy adult subjects as a control group. All participants were subjected to history taking, otological examination, basic audiological evaluation, bedside examination of the dizzy patient, cVEMP, oVEMP, and posturography tests.Results35% of migraine patients showed delayed cVEMP latency and 40% showed abnormal oVEMP in the form of statistically significant delayed right oVEMP P1 (p = 0.050) and left oVEMP N1 latency (p = 0.038) compared with controls. cVEMP parameters were not correlated to posturography results. The majority of migraine patients (70%) had normal equilibrium pattern and normal sensory analyses ratios (65%). Only 30% had vestibular dysfunction.ConclusionsVSR and VOR are affected in migraine patients. We recommend the use of cVEMP and oVEMP in migraine patients for functional assessment of brainstem pathways.

Background: Fibromyalgia (FM) is a non-inflammatory musculoskeletal chronic syndrome, whose etiology is unknown, characterized by diffuse pain, many patients with FM were reported to have dizziness which is attributed to hypotension and the autonomic nervous system (ANS) dysfunction. Aim: To improve management of patients with fibromyalgia having dizziness. Objective: to assess peripheral vestibular functions in patients with fibromyalgia. Subjects and Methods: After obtaining approval from the Ethics Committee of the Suez Canal University Hospital (registration number:3646) and written informed patient consent, a Cross-sectional study was conducted at Suez Canal University hospital from June 2018 to December 2019 in the Audio-Vestibular Clinic of the E.N.T department, including 30 female subjects whose age ranged from 22 to 50 years and were divided into Study group that comprised patients diagnosed with fibromyalgia and Control group rather healthy individuals. The vestibular assessment was done using pure tone audiometry, Bedside tests, and video-nystagmography (VNG). Results: There was no statistically significant difference between both groups regarding results of bedside examinations and VNG results as a caloric test (p-value = 0.6) however, there was a trend towards positive results and an increase in vestibular weakness in the fibromyalgia group compared to the control group. Conclusion: Fibromyalgia is unlikely to be a cause of peripheral vestibular dysfunction, so vestibular testing is not routinely recommended for such patients.

Background: Sudden sensorineural hearing loss is considered a labyrinthine crisis, where the vestibular system is exposed to damage as well as the cochlea. Many trials have been made to prove the existence of such damage, in this study; we have utilized the VEMP and vHIT to characterize this vestibular insult and classify it into distinguishable patterns. Aim: To characterize the vestibular insult associated with sudden sensorineural hearing loss (SSNHL) using vestibular evoked myogenic potential (VEMP) and video head impulse test (vHIT). Patients and Methods: This cross-sectional descriptive study was carried out on 31 patients with SSNHL presenting to Audiovestibular Medicine outpatient clinic in SCU hospital from April 2017 to Sep. 2018. Subjects with unilateral sudden diminution of hearing >30 dB in three or more consecutive frequencies were included. A full audiological evaluation was done in addition to the VEMP both (cervical & ocular) and vHIT. Results were analyzed and combined into four main different patterns by authors. Results: Among 31 subjects with SSNHL, 7 patients (22%) had Type 1 (cochlear insult but no vestibular pattern), 14 patients, (45%) had Type II (otolithic involvement: saccule and/or utricle), 6 patients (19%) had type III (otolithic and semicircular canals involvement) and 4 patients (12%) had type IV (complete vestibular loss). Conclusion: Vestibular insult in SSNHL was categorized into four types. Seventy eighty percent of patients had otolithic organ affection (Type I, II, and III) while SCC insult was present in only 32% of patients (Type II and III) with SSNHL.

Hypertriglyceridemia is a common problem in adults in the developed world. It is associated with increased levels of triglycerides within the blood, which subsequently promote the development of other diseases such as cardiovascular disease and pancreatitis. Triglycerides are mostly consumed through the diet and act as a source of energy in between meals. However, the levels of triglycerides increase proportionally with the number of calories consumed. This only leads to a problem if the total daily energy expenditure is exceeded.

Objective:To explore the role of the nine-step inflation/deflation tympanometric test and resting middle-ear pressure range as predictors of barotrauma in aircrew members.Methods:A prospective, non-randomised study was conducted on 100 aircrew members. Resting middle-ear pressure was measured and the nine-step inflation/deflation test performed on all subjects before flights. Subjects were allocated to two groups according to resting middle-ear pressure range (group A, within the range of +26 to +100 and −26 to −100 mmH2O; group B, −25 to +25 mmH2O). All aircrew members were assessed after flights regarding the presence and the grade of barotrauma.Results:In both groups, the sensitivity and specificity values of the entire post-inflation/deflation test were close to those of the post-deflation part of the test. The post-deflation test had a higher negative predictive value than the post-inflation test. Ears with resting middle-ear pressure lower than −55 mmH2O experienced barotrauma, regardless of good or poor post-inflation or post-deflation test results.Conclusion:In an aircrew member, a resting middle-ear pressure within the range of −55 and +50 mmH2O, together with good post-deflation test results, are considered reliable predictors for fitness to fly.

BackgroundNoise has been a major problem to mankind and induces many auditory and extra-auditory hazards.Aim of the workThis study was carried out to determine the injurious effects of noise on the hippocampus and to show whether Ginkgo biloba has any modulatory effect on hippocampal injury.Material

The Amplitude Versus Azimuthal AVAZ analysis has proved to be an important tool for characterizing fracture distributions and orientations of hydrocarbon reservoirs. This paper is aiming at the application of this tool for characterizing the fractures in Bahrain field reservoirs. Better understanding of faults and fractures distribution is essential to optimize EOR strategy and reservoir management. Regional analysis is possible by looking at faults distribution characterized by structural attributes analysis validated by regional stress and geological information. The investigation at local scale is more cumbersome but an Amplitude Variation with Azimuth (AVAz) method based on azimuthal Fourier Coefficients (FCs) proves to be a simple and powerful tool to characterize fractures distribution validated by FMI data. The anisotropy information was then used to update and improve the reservoir model long production history matching.

Many research works had been carried out to study the aerodynamic behavior of different ground vehicles in order to enhance their stability and determine the aerodynamic forces acting on them. The present work focused on studying the aerodynamics of a bus model that resembles actual working buses. The study considered the pressure distribution around the bus model and determination of lift and drag forces acting. Two cases were considered; straight orientation of the bus model (i.e. parallel to the air stream) and when the bus model was yawed by an angle of 10˚ to the direction of air stream.

Background. Obstructive sleep apnoea (OSA) is common in children yet often overlooked, as symptom-based screening is unreliable. Polysomnography is regarded as the gold standard for the diagnosis of OSA, but is not widely available in South Africa (SA). Overnight oximetry is a validated screening tool for OSA. Objectives. To describe the impact and utility of overnight oximetry at a tertiary children’s hospital in SA. Methods. A retrospective descriptive study was conducted of patients screened for OSA by overnight oximetry at a paediatric referral hospital from December 2012 to December 2014. Clinical data were retrieved from the oximetry database and medical records. Recordings of ≥6 hours were considered adequate and included in the study. OSA severity was determined using the McGill score. Details on management and outcome were documented. Results. Oximetry studies in 137 of 153 patients were suitable for analysis (88 males (64.2%), median age 31.4 months (interquartile range (IQR) 15.8 - 65.8). Adenotonsillar hypertrophy was common ( n =97, 70.8%), and 65 children (47.4%) had two or more underlying OSA risk factors. McGill’s score classified patients as follows: no/mild OSA n =55 (40.1%), moderate OSA n =23 (16.8%), severe OSA n =23 (16.8%) and very severe OSA n =36 (26.3%). Male gender, adenotonsillar hypertrophy and a lower weight-for-age z -score (–1.3 v. –0.7; p =0.038) were associated with severe to very severe OSA. Seventy-eight children (56.9%) were referred for surgery, 33 (24.1%) receiving urgent surgery within a median of 6 days (IQR 4 - 12). In contrast, 59 children (43.1%) with suspected OSA did not require surgical intervention. Conclusions. Overnight oximetry is a simple low-cost tool to assess severity of OSA and prioritise appropriate OSA management in resource-constrained settings such as SA.

Objective:To study the possible damage to the vestibular system in patients with post-mumps sensorineural hearing loss.Methods:Nineteen patients with recent mumps infection participated in the study. All patients had unilateral profound sensorineural hearing loss or total hearing loss. Patients were subjected to video-nystagmography and vestibular-evoked myogenic potential testing.Results:Eight patients (42.1 per cent) had normal video-nystagmography results and intact vestibular-evoked myogenic potentials on both sides, whereas the other 11 patients (57.9 per cent) had vestibular lesions in the form of marked canal weakness and absent vestibular-evoked myogenic potential responses on the same side as hearing loss. The overall findings indicated a peripheral site for the lesions.Conclusion:The majority of patients with post-mumps sensorineural hearing loss had peripheral vestibular pathology in the same ear as hearing loss. Further research should be directed to saving the inner ear following mumps infection.

Mobile Ad Hoc networks (MANETs) are gaining increased interest due to their wide range of potential applications in civilian and military sectors. The self-control, self-organization, topology dynamism, and bandwidth limitation of the wireless communication channel make implementation of MANETs a challenging task. The Connected Dominating Set (CDS) has been proposed to facilitate MANETs realization. Minimizing the CDS size has several advantages; however, this minimization is NP complete problem; therefore, approximation algorithms are used to tackle this problem. The fastest CDS creation algorithm is Wu and Li algorithm; however, it generates a relatively high signaling overhead. Utilizing the location information of network members reduces the signaling overhead of Wu and Li algorithm. In this paper, we compare the performance of Wu and Li algorithm with its Location-Information-Based version under two types of Medium Access Control protocols, and several network sizes. The MAC protocols used are: a virtual ideal MAC protocol, and the IEEE 802.11 MAC protocol. The use of a virtual ideal MAC enables us to investigate how the real-world performance of these algorithms deviates from their ideal-conditions counterpart. The simulator used in this research is the ns-2 network simulator.

Luneberg lens is a new generation of antennas that is developed in the last few years and inserts itself strongly in Microwaves, Communications and Telescopes area. The idea of this research is to improve the radiation pattern by decreasing the side lobes and increasing the main lobe. The new design is proposed to work in the X-band. The simulated result and analysis are presented.

This paper predicts the effect of the user-s hand-hold position on the Total Isotropic Sensitivity (TIS) of GSM900/1800 mobile phone antennas of realistic in-use conditions, where different semi-realistic mobile phone models, i.e., candy bar and clamshell, as well as different antenna types, i.e., external and internal, are simulated using a FDTD-based platform. A semi-realistic hand model consisting of three tissues and the SAM head are used in simulations. The results show a considerable impact on TIS of the adopted mobile phone models owing to the user-s hand presence at different positions, where a maximum level of TIS is obtained while grasping the upper part of the mobile phone against head. Maximum TIS levels are recorded in talk position for mobile phones with external antenna and maximum differences in TIS levels due to the hand-hold alteration are recorded for clamshell-type phones., {"references":["Z. N. Chen, Antennas for Portable Devices, John Wiely & Sons, 2007.","Allgon, \"Feasibility Study of UE Antenna Efficiency Test Methods,\"\nTSG-RAN Working Group 4 (Radio) Meeting, Gothenburg, Sweden\n(TSG R4-(01)0630):1-8, May 2001.","Methods of Measurements for Radiated RF Power and Receiver\nPerformance, (Draft Revision 0.6-A), Cellular Telecommunications\nIndustry Association (CTIA), January 2001.","M. B. Knudsen, \"Antenna Systems For Handsets,\" ATV-Industrial\nPh.D. Project EF-755, Siemens Mobile Phones A/S, September 2001.","Bo G. H. Olsson and Stig-Aake A. Larsson, \"Description of Antenna\nTest Method Performed in Scattered Field for GSM MS,\"\nCOST259WG2.2, 1998.","S. Prasad, P. Ramachandran, A. A. Glazunov and C. Beckman,\n\"Evaluation of the Telia scattered field measurement methoth for\nestimation of in-network performance of mobile terminal antennas,\" in\nProc. 29th Annual Symposium of the Antenna Measurement Techniques\nAssociation (AMTA)-2007, St.Louis, MO, USA.","C. Orlenius, P.-S. Kildal and G. Poilasne, \"Measurements of total\nisotropic sensitivity and average fading sensitivity of CDMA phones in\nreverberation Chamber,\" in Proc. IEEE AP-S International Symposium,\nWashington, DC, vol. 1A, pp. 409-412, July 2005.","C. Orlenius, N. Serafimov, P.-S. Kildal, \"Procedure for measuring\nradiation efficiency in downlink band for active mobile phones in a\nreverberation chamber,\" in Proc. IEEE AP-S International Symposium,\nvol. 4, pp. 731-734, June 2003.","SEMCAD X Reference Manual, SEMCAD Simulation Platform for\nElectromagnetic Compatibility, Antenna Design and Dosimetry,\"\nSPEAG - Schmid & Partner Engineering AG (see\nhttp://www.semcad.com).\n[10] S. I. Al-Mously and M. M. Abousetta, \"A novel cellular handset design\nfor an enhanced antenna performance and a reduced SAR in the human\nhead,\" International Journal of Antennas and Propagation (IJAP), vol.\n2008, Article ID 642572, 10 pages, 2008. doi:10.1155/2008/642572.\n[11] S. I. Al-Mously and M. M. Abousetta, \"Anticipated Impact of Hand-\nHold Position on the EM Interaction of Different Antenna\nTypes/Positions and a Human in Cellular Communications,\"\nInternational Journal of Antennas and Propagation (IJAP), submitted\nfor publication\n[12] K. S. Yee, \"Numerical solution of initial boundary value problems\ninvolving Maxwell-s equations in isotropic media,\" IEEE Transaction\non Antennas and Propagation, vol. 14, no. 3, pp. 302-307, 1966.\n[13] N. Chavannes, R. Tay, N. Nikoloski, and N. Kuster, \"Suitability of\nFDTD-based TCAD tools for RF design of mobile phones,\" IEEE\nAntennas and Propagation Magazine, vol. 45, no. 6, pp. 52-66, 2003.\n[14] S. I. Al-Mously and M. M. Abousetta, \"A study of the hand-hold impact\non the EM interaction of a cellular handset and a human head,\"\nInternational Journal of Electronics, Circuits, and Systems (IJECS), vol.\n2, no. 2, pp. 91-95, Spring 2008.\n[15] Recommended Practice for Determining the Peak Spatial-Average\nSpecific Absorption Rate (SAR) in the Human Head from Wireless\nCommunications Devices - Measurement Techniques, IEEE Standard-\n1528, December 2003.\n[16] Basic Standard for the Measurement of Specific Absorption Rate Related\nto Exposure to Electromagnetic Fields from Mobile Phones (300 MHz-\n3GHz), European Committee for Electrical Standardization\n(CENELEC), EN-50361, 2001.\n[17] Procedure to measure the Specific Absorption Rate (SAR) in the\nfrequency range of 300 MHz to 3 GHz - Part 1: hand-held mobile\nwireless communication devices, International Electrotechnical\nCommission, committee draft for vote, IEC 62209.\n[18] Specific Absorption Rate (SAR) Estimation for Cellular Phone,\nAssociation of Radio Industries and businesses, ARIB STD-T56, 2002.\n[19] Evaluating Compliance with FCC Guidelines for Human Exposure to\nRadio Frequency Electromagnetic Field, Supplement C to OET Bulletin\n65 (Edition 9701), Federal Communications Commission (FCC),\nWashington, DC 1997.\n[20] B. B. Beard, W. Kainz, T. Onishi, T. Iyama, S. Watanabe, O. Fujiwara,\nJ. Wang, G. Bit-Babik, A. Faraone, J. Wiart, A. Christ, N. Kuster, A.\nLee, H Kroeze, M. Siegbahn, J. Keshvari, H. Abrishamkar, W. Simon,\nD. Manteuffel, and N. Nikoloski, \"Comparisons of computed mobile\nphone induced SAR in the SAM phantom to that in anatomically correct\nmodels of the human head,\" IEEE Transaction on Electromagnetic\nCompatibility, vol. 48, no. 2, pp. 397-407, 2006.\n[21] IEEE Standard for Safety Levels with respect to human exposure to\nradio frequency electromagnetic fields, 3 kHz to 300 GHz, Amendment\n2: Specific Absorption Rate (SAR) Limits for the Pinna, IEEE Standard\nC95.1b-2004, Dec. 2004.\n[22] P. Lindberg, \"Wideband active and passive antenna solutions for\nhandheld terminals,\" Digital comprehensive summaries of Uppsala\nDissertations from the faculty of science and technology 266, Uppsala\nUniversity, 2007."]}

To maximize recovery from carbonate reservoirs it is necessary to build models that include as much detail as possible about the variations in reservoir properties. Due to the heterogeneous nature of many carbonate rocks the standard techniques of building a porosity model by using well data alone can produce models that do not accurately represent the true subsurface geology. Seismic data is another source of information that can provide valuable details about the changes in porosity away from well control. An inversion was performed on a seismic volume over an Abu Dhabi field to generate an acoustic impedance model of the reservoir. Using the acoustic impedance, available well data and other seismic attributes a neural net project was performed to produce a porosity volume. The porosity volume was in agreement with porosity log data at the well locations and showed lateral porosity variations that could be used to update the porosity in the reservoir model. A porosity volume was also calculated from the inversion acoustic impedance results using a porosity to acoustic impedance relationship derived from the log data. The inversion porosity model was used as and additional control on the neural net porosity from seismic results and for validation. The porosity from the neural net project was transferred to the reservoir model building software and successfully used to validate and update the porosity in the reservoir model away from well control. The revised porosity model more accurately showed the affects of faults on porosity and porosity changes due to digenesis and facies changes. The added details and more accurate lateral variations in reservoir porosity obtained from seismic information has the potential to produce more accurate and reliable simulation models showing the dynamic behavior of the reservoir.

A program of 2D seismic lines was acquired in a transition zone in Abu Dhabi in early 2007. The objective was to firm up exploration concepts in the cretaceous, including subtle reefal buildups. Three data issues were of concern, namely, matching the different seismic sources and receivers, static corrections, and noise attenuation for improved signal-to-noise ratio. Because transition-zone acquisition entails dealing with a variety of environments, it was necessary to use two types of sources, namely air gun arrays and dynamite, and three types of receivers - marsh geophones, hydrophones, and dual sensor units. Matching of the resulting six source-receiver combinations was a key challenge. The dynamic and complex nature of transition zones, situated between land and marine environments, causes noise levels to be particularly high. Mitigation of seismic noise was the second processing challenge. Finally, the low-relief structures that were the targets in this area placed stringent demands on the static solutions. Coming up with an accurate static solution was the third processing challenge. This project provided a unique case study in transition-zone processing, because the data was sent for processing by three contractors. This was done to verify that optimum processing has been performed on the data to meet the interpretation objectives. This afforded a rare and unique opportunity to compare three state-of the-art approaches to transition-zone seismic processing. This paper presents comparisons of the final migrated images obtained using the three processing approaches. It also refers to further analysis carried out using well-to-seismic ties and acoustic impedance sections produced by post-stack inversion. We will conclude with the key lessons gained from this experience, which we hope will find application to other projects dealing with this particularly challenging problem.

This paper investigates the impact of the hand-hold positions on both antenna performance and the specific absorption rate (SAR) induced in the user-s head. A cellular handset with external antenna operating at GSM-900 frequency is modeled and simulated using a finite difference time-domain (FDTD)-based platform SEMCAD-X. A specific anthropomorphic mannequin (SAM) is adopted to simulate the user-s head, whereas a semirealistic CAD-model of three-tissues is designed to simulate the user-s hand. The results show that in case of the handset in hand close to head at different positions; the antenna total efficiency gets reduced to (14.5% - 5.9%) at cheek-position and to (27.5% to 11.8%) at tilt-position. The peak averaged SAR1g values in head close to handset without hand, are 4.67 W/Kg and 2.66 W/Kg at cheek and tilt-position, respectively. Due to the presence of hand, the SAR1g in head gets reduced to (3.67-3.31 W/Kg) at cheek-position and to (1.84-1.64 W/Kg) at tilt-position, depending on the hand-hold position., {"references":["Recommended Practice for Determining the Peak Spatial-Average\nSpecific Absorption Rate (SAR) in the Human Head from Wireless\nCommunications Devices - Measurement Techniques, IEEE Standard\n1528, 2003.","Product Standard to Demonstrate the Compliance of Mobile Phones\nwith the Basic Restrictions Related to Human Exposure to\nElectromagnetic Fields (300 MHz - 3 GHz), EN 50360, 2001.","Basic Standard for the Measurement of Specific Absorption Rate Related\nto Exposure to Electromagnetic Fields from Mobile Phones (300 MHz -\n3 GHz), EN 50361, 2001.","Procedure to Measure the Specific Absorption Rate (SAR) in the\nFrequency Range of 300 MHz to 3 GHz - Part 1: Hand-held Mobile\nWireless Communication Devices, IEC 62209.","Specific Absorption Rate (SAR) Estimation for Cellular Phone, ARIB\nStandard-T56, 2002.","Evaluating Compliance with FCC Guidelines for Human Exposure to\nRadio Frequency Electromagnetic Fields, supplement C to OET Bulletin\n65 (Edition 9701) FCC, 1997.","Electromagnetic Radiation - Human Exposure, ACA Radio\ncommunications Standard, Schedules 1 and 2, 2003.","S. I. Al-Mously and M. M. Abousetta, \"Study of both antenna and PCB\npositions effect on the coupling between the cellular hand-set and human\nhead at GSM-900 standard,\" iWAT IEEE-2008, International Workshop\non Antenna Technology 2008, Chiba, Japan, March 4-6, 2008, to be\npublished.","J. Graffin, N. Rots and G. F. Pedersen, \"Radiations phantom for\nhandheld phones,\" Vehicular Technology Conference, 2000, IEEE VTSFall\nVTC 2000, 52nd, Volume 2, pp. 853 - 866, 24-28Sept. 2000\n[10] N. Chavannes, P. Futter, R. Tay, K. Pokovic and N. Kuster, \"Reliable\nprediction of MTE performance under real usage conditions using\nFDTD,\" in Proc. of Applied Electromagnetics and Communications\n18th Int. Conf., 2005\n[11] Chin-Ming Su, Chin-Hsien Wu, Kin-Lu wong, Shin-Huang Yeh and\nChia-Lun Tang, \"User-s hand effects on EMC internal GSM/DCS\nmobile phone antenna,\" Antennas and Propagation Society International\nSymposium 2006, IEEE, 9-14 July 2006.\n[12] SEMCAD-X Reference Manual, SEMCAD Simulation Platform for\nElectromagnetic Compatibility, Antenna Design and Dosimetry,\"\nSPEAG - Schmid&Partner Engineering AG. (http://www.semcad.com)\n[13] K. Ogawa and T. Uwano, \"A diversity Antenna for very small 800-MHz\nband portable telephones,\" IEEE Trans. Antenna and Propagation, vol.\n42, No. 9, September 1994.\n[14] B. B. Beard, W. Kainz, T. Onishi, T. Iyama, S. Watanabe, O. Fujiwara,\nJ. Wang, G. Bit-Babik, A. Faraone, J. Wiart, A. Christ, N. Kuster, A.\nLee, H. Kroeze, M. Siegbahn, J. Keshvari, H. Abrishamkar, W. Simon,\nD. Manteuffel, and N. Nikoloski, \"Comparisons of computed mobile\nphone induced SAR in the SAM phantom to that in anatomically correct\nmodels of the human head,\" IEEE Trans. Electromagnetic\nCompatibility, vol. 48, No. 2, MAY 2006.\n[15] Safety Levels with Respect to Human Exposure to Radio Frequency\nElectromagnetic Fields, 3 kHz to 300 GHz, Amendment 2: Specific\nAbsorption Rate (SAR) Limits for the Pinna, IEEE Standard C95.1b-\n2004, Dec. 2004.\n[16] H. Arai, Measurement of Mobile Antenna Systems, Artech House Inc,\n2001.\n[17] Recommended Practice for Determining the Peak Spatial-Average\nSpecific Absorption Rate (SAR) Associated with the Use of Wireless\nHandsets - Computational Techniques, IEEE draft Standard-1529.\n[18] L. Kuo, Y. Kan and H. Chuang, \"Analysis of A 900/1800-MHz dualband\ngap loop antenna on a handset with proximate head and hand\nmodel,\" Journal of Electromagnetics Waves and Applications, vol. 21,\nNo. 1, pp. 107-122, 2007."]}

This paper presents a design of a single coaxial-feed stacked rectangular microstrip patch antenna (MPA) with shorting pins. The proposed MPA design is based on the multilayer structure technique, and the cellular hand-set plastic cover is put as a one layer of the MPA structure layers. A finite- element based solver has been used to achieve the proposed design. This stacked MPA can cover most of the GSM-family standards including E-GSM 900 (880-960 MHz), GSM 1800/DCS (1710-1880 MHz) , GSM 1900/PCS (1850-1975 MHz), UMTS (1885-2200 MHz), the global new 3-G IMT-2000 (2500-2690 MHz), and WLAN+Bluetooth applications (2400 MHz) with return loss L rem ges 10 dB. A good agreement was obtained between the simulated and measured results.

In this paper a design of a novel 3-D multi-branch monopole antenna for cellular hand-set and portable equipments will be presented. The proposed design is covering most GSM family standards including the UMTS, the global new IMT-2000, and WLAN+ Bluetooth. Using the adopted design, multi-frequency operation including four, five and six operating bands can be achieved. Also, with an optimized design, some bands can be merged to obtain multi-wideband antenna that covering most of cellular standards.

In this paper novel different constructions of a monopole antenna including stepped, up-tapered stepped, up-down-tapered stepped and down-up-tapered stepped constructions were suggested. It was shown through this work that the centre frequency of the adopted constructions can be reduced by more than 30% and the bandwidth can be increased to about 150%-200% with a return loss L retn ≥ 10 dB, as compared with the quarter-wave monopole antenna at the same physical length. Optimized models for the suggested antenna constructions were achieved with the assistance of a Finite Element-Based . Solver and designed practically with a centre frequency around 900-MHz to cover the E-GSM-900 (880 MHz - 960 MHz) frequency.

Operating with multi-frequency and simultaneously mitigating the EMW hazard in the handset mobile telephone is the aim of this paper. To achieve this goal three arrays are constructed, each array, which contains three elements, corresponding to a different operating frequency. The operating frequencies chosen were 966.8 MHz, 1861 MHz and 1980 MHz. This choice enables the mobile to be compatible with different worldwide operating systems namely GSM-900, DCS-1800, PCS-1900 and DECT. The dimensions of each array and hence the power radiation pattern shall contribute greatly towards mitigating the hazard caused by the EM field radiated usually from the mobile set antenna.

In the paper an attempt to solve the problem of electromagnetic wave (EMW) hazard caused by the radiation from hand-set mobile antenna as well as the problem of the hand-set mobile operation with differently tuned frequencies was suggested. A quarter-wave triple-two-element array antenna was implemented to fulfill these requirements. This antenna configuration was capable of operating with three different tuned frequencies 817.5 MHz, 1751.5 MHz and 1984 MHz. Moreover the radiation pattern of each tuned frequency has a notch in the direction of the handset user's head. Using such array antenna in the hand-set mobile telephone makes it compatible with the worldwide different operating systems namely GSM-900, PCS-1800, DCS-1900 and DECT and also safer to use than the hand-set mobile with single monopole or helical antenna.