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The purpose of this paper is to propose a new design strategy to enhance the bandwidth and efficiency of the power amplifier.

To realize the introduced design strategy, a power amplifier was designed using TSMC CMOS 0.18um technology for operating in the Ka-band, i.e. the frequency range of 26.5-40 GHz. To design the power amplifier, first, a power divider (PD) with a very wide bandwidth, i.e. 1-40 GHz, was designed to cover the whole Ka-band. The designed Doherty power amplifier consisted of two different amplification paths called main and auxiliary. To amplify the signal in each of the two pathways, a cascade distributed power amplifier was used. The main reason for combining the distributed structure and cascade structure was to increase the gain and linearity of the power amplifier.

Measurements results for designed power dividers are in good agreement with simulations results. The simulation results for the introduced structure of the power amplifier indicated that the gain of the proposed power amplifier at the frequency of 26-35 GHz was more than 30 dB. The diagram of return loss at the input and output of the power amplifier in the whole Ka-band was less than −8dB. The maximum power-added efficiency (PAE) of the designed power amplifier was 80%. The output P1dB of the introduced structure was 36 dB and the output power of the power amplifier was 36 dBm. Finally, the IP3 value of the power amplifier was about 17 dB.

The strategy presented in this paper is based on the usage of Doherty and distributed structures and a new wideband power divider to benefit from their advantages simultaneously.

Movies critics believe that the diversity of Iranian cinematic genres has decreased over time. The paper aims to answer the following questions: What is the impact of the continuous cooperation between the key nodes on the audience's taste, uniformity of the cinematic genres and the box office? Is there any relationship between the importance of actors in the actors' network and their popularity?

In the artistic world, artists' relationships lead to a network that affects individuals' commercial or artistic success and defines the artwork's value. To study the issue that the diversity of Iranian cinematic genres has decreased over time, the authors utilized social network analysis (SNA), in which every actor is considered a node, and its collaboration with others in the same movies is depicted via edges. After preparing the desired dataset, networks were generated, and metrics were calculated. First, the authors compared the structure of the network with the box office. The results illustrated that the network density growth negatively affects box office. Second, network key nodes were identified, their relationships with other actors were inspected using the Apriori algorithm to examine the density cause and the cinematic genre of key nodes, and their followers were investigated. Finally, the relationship between the actors' Instagram follower count and their importance in the network structure was analyzed to answer whether the generated network is acceptable in society.

The social problem genre has stabilized due to continuous cooperation between the core nodes because network density negatively impacts the box office. As well as, the generated network in the cinema is acceptable by the audience because there is a positive correlation between the importance of actors in the network and their popularity.

The novelty of this paper is investigating the issue raised in the cinema industry and trying to inspect its aspects by utilizing the SNA to deepen the cinematic research and fill the gaps. This study demonstrates a positive correlation between the actors' Instagram follower count and their importance in the network structure, indicating that people follow those central in the actors' network. As well as investigating the network key nodes with a heuristic algorithm using coreness centrality and analyzing their relationships with others through the Apriori algorithm. The authors situated the analysis using a novel and original dataset from the Iranian actors who participated in the Fajr Film Festival from 1998 to 2020.

This study aims to report the development and experimental evaluation of three innovative corrosion-resistant modified epoxy coatings, namely, nanocomposite/toughened, self-healing and hybrid epoxy coatings, for application on steel substrates.

The corrosion resistance of these coatings was evaluated in a highly corrosive environment of salt fog spray for 2,500 h of exposure. Electrochemical impedance spectroscopy (EIS) measurements in sustained exposure to NaCl in a saturated Ca(OH)2 solution, rust creepage measurements at the location of scribe formed in the coatings and adhesion strength test were used to assess the performance of the innovative coatings. Commercially available marine-grade protective epoxy coatings were used as the reference coatings.

The test results showed that the modified epoxy coatings exhibited excellent corrosion resistance when exposed to an aggressive environment for extended periods. The EIS measurements, rust creepage measurements, pull-off strength and visual appearance of the aged modified–epoxy–coated specimens confirmed the enhanced corrosion resistance of the modified epoxy coatings.

Among the three types of modified coatings, the hybrid epoxy coating stands out to be the best performer.

This paper focuses on the way users navigate bibliographic families not only when a user has no specific document in mind but also when he/she has a specific predefined need in mind.

To this end, the Epic of Kings was selected as a test-bed for the study and both situations were studied based on International Federation of Library Associations and Institutions-Library Reference Model (IFLA-LRM), but the potential users (participants of this study) were not directly exposed to the entities of the model. Card sorting, interview and distributing questionnaire constituted the data-gathering process.

Almost all of the participants in this study, when they had no specific resource in mind, generated a top-down view of the family, and in this view, all of them disregarded the item entity and lots of them disregarded the manifestations also. Yet on the other side, when they were asked to assume themselves in certain situations (in need of a specific work with a predefined expression and format), they viewed the bibliographic family from a bottom-up approach.

Most of the studies in this area regard the navigation process of users as a top-down approach and the Functional Requirements for Bibliographic Records (FRBR) family as a model suitable for hierarchical top-down visualization of bibliographic families. Yet this study poses the bottom-up approach of users regarding the family.