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Automatic modulation recognition (AMR) is a challenging problem in intelligent communication systems and has wide application prospects. At present, although many AMR methods based on deep learning have been proposed, the methods proposed by these works cannot be directly applied to the actual wireless communication scenario, because there are usually two kinds of dilemmas when recognizing the real modulated signal, namely, long sequence and noise. This paper aims to effectively process in-phase quadrature (IQ) sequences of very long signals interfered by noise.

This paper proposes a general model for a modulation classifier based on a two-layer nested structure of long short-term memory (LSTM) networks, called a two-layer nested structure (TLN)-LSTM, which exploits the time sensitivity of LSTM and the ability of the nested network structure to extract more features, and can achieve effective processing of ultra-long signal IQ sequences collected from real wireless communication scenarios that are interfered by noise.

Experimental results show that our proposed model has higher recognition accuracy for five types of modulation signals, including amplitude modulation, frequency modulation, gaussian minimum shift keying, quadrature phase shift keying and differential quadrature phase shift keying, collected from real wireless communication scenarios. The overall classification accuracy of the proposed model for these signals can reach 73.11%, compared with 40.84% for the baseline model. Moreover, this model can also achieve high classification performance for analog signals with the same modulation method in the public data set HKDD_AMC36.

At present, although many AMR methods based on deep learning have been proposed, these works are based on the model’s classification results of various modulated signals in the AMR public data set to evaluate the signal recognition performance of the proposed method rather than collecting real modulated signals for identification in actual wireless communication scenarios. The methods proposed in these works cannot be directly applied to actual wireless communication scenarios. Therefore, this paper proposes a new AMR method, dedicated to the effective processing of the collected ultra-long signal IQ sequences that are interfered by noise.

Currently, massive multiple-input multiple-output (m-MIMO) antennas are typically designed using complex trial-and-error methods. The purpose of this study is to determine an effective optimization method to achieve more efficient antenna design processes.

This paper presents the design stages of a m-MIMO antenna array compatible with 5G smartphones operating in long term evolution (LTE) bands 42, 43 and 46, based on a specific algorithm. Each antenna element in the designed 10-port m-MIMO antenna array is intended to perfectly cover the three specified LTE bands. The optimization methods used for this purpose include the Nelder–Mead simplex algorithm, covariance matrix adaptation evolution strategy, particle swarm optimization and trust region framework (TRF).

Among the primary optimization algorithms, the TRF algorithm met the defined objectives most effectively. The achieved antenna efficiency values exceeded 60.81% in the low band and 68.39% in the high band, along with perfect coverage of the desired bands, demonstrating the success of the design with the TRF algorithm. In addition, the potential electromagnetic field exposure caused by the designed m-MIMO antenna array is elaborated upon in detail using computational human models through specific absorption rate analysis.

The comparison of four different algorithms (two local and two global) for use in the design of a 10-element m-MIMO antenna array with a complex structural configuration and the success of the design implemented with the selected algorithm distinguish this study from others.

The purpose of this paper is to explore the feasibility of mud brick houses as an alternative to the more widely adopted emergency shelters used in war-torn Syria. It focuses on the mud houses’ sustainability, cost effectiveness, cultural preference, income generation and security.

This study uses a qualitative research approach to a single case study. Interviews were conducted with field experts from the Qatar Red Crescent Society and members of the internally displaced persons (IDPs) community living in mud brick houses.

The findings reveal that the utilisation of mud houses is a good alternative in relief efforts. The houses are sustainable and cost-effective, take into consideration cultural dynamics and provide economic empowerment to IDPs. However, the maintenance of mud brick houses turns out to be the largest flaw, and this problem requires further research.

The paper highlights the inefficiency of current emergency sheltering practices in Syria and reveals that tents are not a preferred mode of shelter. It further sheds light on a unique case study in which mud houses were used by an aid and development organisation, highlighting its strengths and weaknesses. This paper contributes to practical discussion and ideation on more appropriate housing for IDPs.

This paper explores the role of accounting and accountability techniques in contributing to Australia’s border industrial complex.

We use the political thought of Behrouz Boochani to explore the role that accounting techniques play at the micro and macro level of his dialectic of alienation and freedom. Firstly, we explore the accounting and accountability techniques detailed in Boochani’s No Friend but the Mountain, which gives an account of his life in Manus Prison, and the accounting techniques he experienced. Secondly, we explore the discourse of alienation created within the annual reporting of the Australian Federal Government regarding the border industrial complex.

We argue that the border industrial complex requires the alienation of asylum seekers from their own humanity for capital accumulation, and that accounting and accountability techniques facilitate this form of alienation. These techniques include inventorying, logging and queuing at the micro level within Manus Prison. This alienates those trapped in the system from one another and themselves. Techniques also include annual reporting at a macro level which alienates those trapped in the system from the (White) “Australian Community”. However, these techniques are resisted at every point by assertions of freedom.

We illustrate the role of accounting in accumulation by alienation, where the unfreedom of incarcerated asylum seekers is a site of profit for vested interests. But also that this alienation is resisted at every point by refusals of alienation as assertions of freedom. Thus, this study contributes to the accounting literature by drawing from theories of alienation, and putting forward the dialectic of alienation and freedom articulated by Boochani and collaborators.

The service environment is becoming increasingly turbulent, leading to calls for a systemic understanding of it as a set of dynamic service ecosystems. This paper advances this understanding by developing a typology of service ecosystem dynamics that explains the varying interplay between change and stability within the service environment through distinct behavioral patterns exhibited by service ecosystems over time.

This study builds upon a systematic literature review of service ecosystems literature and uses system dynamics as a method theory to abductively analyze extant literature and develop a typology of service ecosystem dynamics.

The paper identifies three types of service ecosystem dynamics—behavioral patterns of service ecosystems—and explains how they unfold through self-adjustment processes and changes within different systemic leverage points. The typology of service ecosystem dynamics consists of (1) reproduction (i.e. stable behavioral pattern), (2) reconfiguration (i.e. unstable behavioral pattern) and (3) transition (i.e. disrupting, shifting behavioral pattern).

The typology enables practitioners to gain a deeper understanding of their service environment by discerning the behavioral patterns exhibited by the constituent service ecosystems. This, in turn, supports them in devising more effective strategies for navigating through it.

The paper provides a precise definition of service ecosystem dynamics and shows how the identified three types of dynamics can be used as a lens to empirically examine change and stability in the service environment. It also offers a set of research directions for tackling service research challenges.

This paper explores whether data back the claim that imports of armaments are inherently bad for economic growth. Regardless of one's point of view, the production and trade of weaponry is a significant industry with serious economic implications that warrant investigation. The financial repercussions of military spending have been extensively studied, but the economic effects of arms importation remain unknown.

This study adopts a pooled mean group approach to investigate the nexus between arms imports, military expenditure and per capita GDP for a balanced panel of twenty-five of the top arms importers in the world from 2000 to 2021.

The authors find that arms imports and military spending negatively impact GDP per capita in the short run, but military spending is beneficial over the long run. The authors also used the Dumitrescu Hurlin Granger causality test, which revealed a unidirectional causation between per capita GDP and military expenditure, and a unidirectional causal relationship from military spending to arms imports.

This paper is deficient in a few aspects: first, it looks at only those countries comprising the top 70% of arms imports. Second, it omits many political, technological and legal factors that impact arms imports and military expenditures.

This paper looks into the impact of defense spending and arms imports on economic growth for twenty-five nations with the highest share of arms imports in recent times. It is a significant addition to the literature as it resolves the debate of whether or not the military expenditure is wasteful and whether arms imports significantly harm the nation's economic growth.

The paper aims to measure the nature and extent of international diversification followed by Indian companies over the period 2009–10 to 2017–18. The study also aims to assess the pattern of transition of companies to various strategies of international diversification.

Jacquemin and Berry’s (1979) entropy approach has been applied to measure the extent and assess the nature of international diversification. Further, the study deploys two-dimensional categorical framework advocated by Vachani (1991) and categorizes the firms into four international diversification strategies.

Larger proportion of companies in internationally low diversification (ILD) strategy reveals low extent of international diversification of Indian companies. The pattern of diversification depicts that the trend of moving forward is speeding up sequentially toward higher strategies of growth. Both the extent and pattern depict that the nature of diversification is shifting from relatedness to un-relatedness with transitions from intra-regions to inter-regions. The study confirms the applicability of eclectic theory and psychic distance Uppsala model in determining the preference of international diversification strategies and process of internationalization respectively in Indian firms.

The paper is first of its kind on account of several reasons. First, such a comprehensive evaluation of preferences for international diversification strategies has never been taken up with reference to emerging economies, especially India. Second, the paper is not static and does not limit itself only to the identification of favored strategies of Indian companies but also gauges the transitional behavior of Indian companies across different strategies at different points of time. In fact it is the first study to statistically research the applicability of psychic distance model in firms in emerging economy. Third, the results not only measure the quantum of international diversification but also assess the extent of relatedness and un-relatedness followed by Indian companies.

The purpose of the paper is to showcase the significant achievements of Egypt's scientists in the 20th century across various fields of study such as medicine, physics, chemistry, biology, math, geology, astronomy and engineering. The paper highlights the struggles and successes of these scientists, as well as the cultural, social and political factors that influenced their lives and work. The aim is to inspire young people to pursue careers in science and make their own contributions to society by presenting these scientists as role models for hard work and dedication. Ultimately, the paper seeks to promote the importance of science and its impact on society.

The purpose of this review is to present the scientific biographies of Egypt's most distinguished scientists, primarily in the field of Natural Sciences, in a balanced and comprehensive manner. The work is objective, honest and abstract, avoiding any bias or exaggeration. The author provides a clear and concise methodology, including a brief introduction to the scientist and their field of study, an explanation of their major contributions, the impact of their work on society, any challenges or obstacles faced during their career and their lasting legacy. The aim is to showcase the important achievements of these scientists, their impact on their respective fields and to inspire future generations to pursue scientific careers.

The group of outstanding scientists in 20th century Egypt were shaped by various factors, including familial upbringing, education, society, political and cultural atmosphere and state support for scientific research. These scientists made significant contributions to various academic disciplines, including medicine, physics, chemistry, biology, mathematics and engineering. Their impact on their communities and cultures has received international acclaim, making them role models for future generations of scientists and researchers. The history of these scientists highlights the importance of educational investments and supporting scientific research to foster innovation and social progress. The encyclopedia serves as a useful tool for students, instructors and education professionals, preserving Egypt's scientific heritage and honouring the scientists' outstanding accomplishments.

The encyclopedia preserves Egypt's scientific heritage, which has been overlooked for political or other reasons. It is a useful tool for a variety of readers, including students, instructors and education professionals, and it offers insights into universally relevant scientific success factors as well as scientific research methodologies. The encyclopedia honours the outstanding scientific accomplishments of Egyptian researchers and their contributions to the world's scientific community.

The practical implications of this paper are several. First, it highlights the importance of education, family upbringing and societal support for scientific research in fostering innovation and social progress. Second, it underscores the need for continued funding and support for scientific research to maintain and build upon the accomplishments of past generations of scientists. Third, it encourages young people to pursue scientific careers and make their own contributions to society. Fourth, it preserves the scientific heritage of Egypt and honors the contributions of its outstanding scientists. Finally, it serves as a useful tool for students, instructors and education professionals seeking to understand the factors underlying scientific success and research methodologies.

The social implications of the paper include promoting national pride and cultural identity, raising awareness of the importance of education and scientific research in driving social progress, inspiring future generations of scientists and researchers, reducing socioeconomic disparities and emphasizing the role of society, politics and culture in shaping scientific researchers' personalities and interests.

The paper's originality/value lies in its comprehensive documentation of the scientific biographies of Egypt's most prominent scientists in the 20th century, providing unique insights into the factors that contributed to their development and their impact across various academic disciplines. It preserves Egypt's scientific heritage and inspires future generations of scientists and researchers through the promotion of educational investments and scientific research. The encyclopedia serves as a useful tool for education professionals seeking to understand scientific success factors and research methodologies, emphasizing the importance of supportive and inclusive environments for scientific development.