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<p class="Abstract">In this study, a compact quarter-mode substrate integrated waveguide (QMSIW) based dual-band antenna is proposed for wireless body area network applications. A QMSIW resonator is realised by splitting the full-mode substrate integrated waveguide cavity along the perfect magnetic conductor walls. The proposed antenna preserves the fundamental mode TE110 and the third order mode TE220 of the square SIW cavity. The proposed antenna is linearly polarised in the lower band at 2.45 GHz and circularly polarised in the higher frequency band at 5.8 GHz. The on-body performance of the antenna is validated on a piece of pork muscle tissue and it has been found to be stable with respect to surroundings. The proposed antenna covers the ISM bands 44 MHz (2.445 GHz - 2.489 GHz) and 225 MHz (5.730 GHz - 5.955 GHz) at 2.45 GHz and 5.8 GHz, respectively. The measured gain of the antenna on pork tissue is 1.87 dBi and 5.5 dBi at two bands. In addition, the specific absorption rate is obtained of 0.65 mW/g and 1.51 mW/g at two bands (wext = 2 mm), averaged over 1 g of muscle with 100mW input power. Moreover, the simulated and experimental results demonstrate a good agreement.</p>

In this study, a planar cavity-backed bow-tie-complementary-ring-slot antenna is proposed, and a new approach for bandwidth enhancement using a shorted-via is introduced. A shorted-via concept overcomes the narrow impedance bandwidth of a conventional substrate integrated waveguide cavity-backed antenna. By adjusting the location of the shorted-via (placed just above the centroid of the radiating slot), the individual bandwidth of the lower and higher order resonances has been tuned below -10 dB criterion, which results in the broadening of the bandwidth. Finally, the antenna is proficient to operate for an impedance bandwidth of 15.71 per cent, ranging from 12.02~14.07 GHz. The proposed antenna shows a gain of better than 4 dBi within the operating band with less than 0.5 dBi variation. Moreover, the antenna preserves good radiation characteristics, which is similar to that of the conventional metallic counterpart. To validate the simulated results, an antenna is fabricated and tested. The simulated results in terms of the reflection coefficient, gain, and radiation patterns are in good agreement with the measured results.

ABSTRACTAccounting for social network effects in marketing strategies has become an important issue. Taking a step back, we seek to incorporate and analyze social network effects on new product development and then propose a model to engineer product diffusion over a social network. We build upon the share‐of‐choice (SOC) problem, which is a strategic combinatorial optimization problem used commonly as one of the methods to analyze conjoint analysis data by marketers in order to identify a product with largest market share, and show how to incorporate social network effects in the SOC problem. We construct a genetic algorithm to solve this computationally challenging (NP‐Hard) problem and show that ignoring social network effects in the design phase results in a significantly lower market share for a product. In this setting, we introduce the secondary operational problem of determining the least expensive way of influencing individuals and strengthening product diffusion over a social network. This secondary problem is of independent interest, as it addresses contagion models and the issue of intervening in diffusion over a social network, which are of significant interest in marketing and epidemiological settings.

AbstractEnvironmental and biological monitoring was carried out in the winter season of 2004 for 30 gasoline station workers (study subjects) and 30 office workers (controls) of Bangalore city, India. Personal air sampling was carried out in the breathing zone of workers using an Anasorb CSC sorbent tube (SKC 226-01) fitted to the low-flow personal samplers (PCXR4 and pocket pump Model No. 210-1002) at a flow rate of 200 ml min−1 during the shift work of 8 h. The benzene content adsorbed in the sorbent tube (SKC 226-01) was desorbed with 1 ml of benzene-free carbon disulfide on a developing vibrator and later analysed by Trace GC fitted with MXT-624 column and flame ionization detector. The mean time weighted average benzene concentration found among study and controls was 1.10±1.08 and 0.070±0.035 mg m−3, respectively. Biological monitoring for benzene exposure was performed by measuring trans,trans muconic acid (t,t-MA) in the end shift urine samples using HPLC-UV technique. End-shift urine samples (1 ml) were adjusted to pH 7–9 with phosphate buffer pH 7.4 passed through the preconditioned Q-SAX anion-exchange cartridge and the (t,t-MA) is extracted with 10% acetic acid and later analysed by HPLC-UV detection The mean t,t-MA found among study and controls were 563.16±281.81 and 266.88±110.65 µg g−1 creatinine. About 50% of the study subjects (15) have higher t,t-MA values than the biological exposure index of the American Conference of Government Industrial Hygienist (ACGIH). Correlation is significant at 5% level (p<0.05) between personal air benzene concentration and urinary t,t-MA in the study group. Based on these findings, the t,t-MA can be used as a biomarker for benzene exposure.

DoS attacks are now so pervasive that virtually any computer connected to a network is vulnerable. This book offers insights into the complexity of the problem as well as the breadth of the research being conducted into the various aspects of the issue.

Historically, women have been victims to a much greater degree than perpetrators of violence. However, the 1970s witnessed the emergence of women as important protagonists in the conflicts across the world. Recent years have witnessed suicide attacks perpetrated by women suicide bombers. This growing trend of women bombers has the general public and counterterrorism specialists concerned because of its implication that women will be key players in future terrorist attacks. Women's role in terrorist organisations have also transformed since 1970s.Women across the ideological spectrum played different roles at different times. The use of women for "soft tasks" like logistics and recruitment gradually started to change in the mid-1980s when they started playing a much more visible frontline role. A woman taking up a suicide bombing role diverges significantly and is far more dangerous than their traditional activity of playing logisticians, recruiters or even a frontline role. This paper scrutinizes this change. There are multi causal issues which drive women to join terrorism and more so as suicide bombers. Psychological, economic, political, religious and sociological factors can act as contributors to understanding the causes that drive women towards terrorism. This paper attempts to highlight the role played by women in various terrorist organisations around the world. It also tries to bring out the factors which influence women to participate in terrorist acts. It aims to bring out the above facts by analysing various groups which have women cadre. Previous studies in the same realm have focused on a particular group or a conflict whereas this paper attempts to examine female participation across multiple conflicts in different groups driven by different ideology, which provides a clear insight into the multi causal factors which are responsible for this trend. The methodology followed is a descriptive one wherein the analysis is conducted on information derived from published secondary data.

AbstractCompetitive imperatives are causing manufacturing firms to consider multiple criteria when designing products. However, current methods to deal with multiple criteria in product design are ad hoc in nature. In this paper we present a systematic procedure to efficiently solve bicriteria product design optimization problems. We first present a modeling framework, the AND/OR tree, which permits a simplified representation of product design optimization problems. We then show how product design optimization problems on AND/OR trees can be framed as network design problems on a special graph—a directed series‐parallel graph. We develop an enumerative solution algorithm for the bicriteria problem that requires as a subroutine the solution of the parametric shortest path problem. Although this parametric problem is hard on general graphs, we show that it is polynomially solvable on the series‐parallel graph. As a result we develop an efficient solution algorithm for the product design optimization problem that does not require the use of complex and expensive linear/integer programming solvers. As a byproduct of the solution algorithm, sensitivity analysis for product design optimization is also efficiently performed under this framework. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 574–592, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10031

Reviews the current status of radioisotope applications in Defence- R&D Establishments, Defence Inspectorates, Ordnance Factories, Public Sector Undertakings under the Defence Ministry, Army, Navy and Air Force Establishments and Military Hospitals. It also lists the users of film badge service in Defence. Training programmes in radioisotope applications in Defence conducted by DRDO organisations have also been highlighted.