Wide dynamic range tranimpedance amplifier using peaking capacitance technique for high speed optical wireless communication system

In the high speed optical communication, the requirement of designing the new optical transceivers is quite challenging due to the bandwidth, noise and environmental conditions for designing the optical transceivers. The optical transceivers design is also challenging because of weak optical signal at the frond-end amplifier. In this paper, the optical transceivers via an optical preamplifier for optical wireless communication is designed. The designed system offers the improved performance in terms of bandwidth and gain compared to existing optical transceivers. It is defined that using the designed system, a high bandwidth of 2.114GHz at 29.72dB gain is achieved. The designed optical transceiver provides the bandwidth enhancement utilizing the peaking inductor and capacitor

Integrated Open Loop Resonator Filter Designed with Notch Patch Antenna for Microwave Applications

This paper presented the design of integrated open loop resonator bandpass filter with notch type antenna for the use in microwave applications. Chebyshev type filter is selected as the filter characteristics and cascaded design with the antenna to produce a single module, Integrated Filter Antenna (IFA). Special feature of the antenna is the implementation of notch on the patch antenna to improve the efficiency. IFA is then simulated in electromagnetic simulation tool, Agilent Advance Design System (ADS) version 2016 and measured using R&S Vector Network Analyzer. It shows that the proposed IFA produced good measured return loss >-30dB with both vertical and horizontal gain of 9.11dBi and 8.01dBi respectively

Integrated Open Loop Resonator Filter Designed with Notch Patch Antenna for Microwave Applications

This paper presented the design of integrated open loop resonator bandpass filter with notch type antenna for the use in microwave applications. Chebyshev type filter is selected as the filter characteristics and cascaded design with the antenna to produce a single module, Integrated Filter Antenna (IFA). Special feature of the antenna is the implementation of notch on the patch antenna to improve the efficiency. IFA is then simulated in electromagnetic simulation tool, Agilent Advance Design System (ADS) version 2016 and measured using R&S Vector Network Analyzer. It shows that the proposed IFA produced good measured return loss >-30dB with both vertical and horizontal gain of 9.11dBi and 8.01dBi respectivel

Detour spectrum and detour energy of conjugate graph complement of dihedral group

Study of graph from a group has become an interesting topic until now. One of the topics is spectra of a graph from finite group. Spectrum of a finite graph is defined as collection of all distinct eigenvalues and their algebraic multiplicity of its matrix. The most related topic in the study of spectrum of finite graph is energy. Energy of a finite graph is defined as sum of absolute value of all its eigenvalues. In this paper, we study the spectrum and energy of detour matrix of conjugate graph complement of dihedral group. The main result is presented as theorems with complete proof

Mapping human genetic diversity in Asia

Asia harbors substantial cultural and linguistic diversity, but the geographic structure of genetic variation across the continent remains enigmatic. Here we report a large-scale survey of autosomal variation from a broad geographic sample of Asian human populations. Our results show that genetic ancestry is strongly correlated with linguistic affiliations as well as geography. Most populations show relatedness within ethnic/linguistic groups, despite prevalent gene flow among populations. More than 90% of East Asian (EA) haplotypes could be found in either Southeast Asian (SEA) or Central-South Asian (CSA) populations and show clinal structure with haplotype diversity decreasing from south to north. Furthermore, 50% of EA haplotypes were found in SEA only and 5% were found in CSA only, indicating that SEA was a major geographic source of EA populations

Coercive Pressures and Anti-corruption Reporting: The Case of ASEAN Countries

This paper aims to investigate the extent of anti-corruption reporting by ASEAN companies and examine whether coercive factors influence the level of disclosure. The authors adopt indicators from the Global Reporting Initiative version 4.0 to measure the extent of anti-corruption disclosures in 117 companies’ reports. Informed by a coercive isomorphism tenet drawn from the institutional theory, the authors propose that several institutional factors influence the extent of their voluntary disclosures. The findings reveal that a large degree of variability difference between the average levels of anti-corruption disclosure in Thailand (434 words) and the Philippines (149 words). The dependence on government tenders and foreign ownership are associated with the level of disclosure. Surprisingly, the United Nation Global Compact membership is not a significant determinant of anti-corruption reporting. This signifies that the membership in the international initiative does not correspond to individual company’s commitment to disclose anti-corruption information. In spite of significant efforts undertaken by global organizations to combat corruption, the level of anti-corruption disclosure is significantly different among the four countries under study. The disclosure of sensitive information such as the confirmed incidences of corruption cases requires careful consideration by the top management as it is subjected to legal implications and reputational risks. Thus, impression management can complement the coercive pressure in explaining the level of anti-corruption reporting. This study is among the first studies which explores the association between coercive factors and the level of anti-corruption disclosure in ASEAN region

Mitochondrial DNA recombination-no need to panic

Recombination has recently been invoked as an explanation for the large amount of homoplasy observed in a collection of complete or nearly complete human mitochondrial sequences. Here we show that some of the data on which this conclusion was based are likely to be unreliable and that if these data are excluded, the results are no longer significant

Optimization of electronics component placement design on PCB using Self Organizing Genetic Algorithm (SOGA)

The optimal placement of electronic components on a printed circuit board (PCB) requires satisfying multiple conflicting design objectives as most of the components have different power dissipation, operating temperature, types of material and dimension. In addition, most electronic companies are currently emphasizing on designing a smaller package electronic system in order to increase the system performance. This paper presents a new self organizing genetic algorithm (SOGA) method for solving this multi-objective optimization problem. The SOGA can be viewed as a cascade of two GAs which consists of two steps fitness evaluation process to ensure that the fitness of selected chromosomes for each iteration process is optimally selected. The algorithm is developed based on weighted sum approach genetic algorithm (WSGA) where an inner loop GA is used to optimize the selection of weights of the WSGA. Experiments are conducted to evaluate the performance of SOGA. Four objective functions are formulated in the experiments which are temperature of components, area of PCB, high power component placement and high potential critical components distance. Comparisons of the performance of SOGA are made with two well known methods namely fixed weight GA (FWGA) and random weighted GA (RWGA). The results show that the SOGA gives a better optimal solution as compared to the other methods