Greater Power Research Articles

China Ties with Iran and Saudi Arabia: A Critical Analysis of Changing Dynamics in Persian Gulf

The complex ties between China and two important Middle Eastern nations Iran and Saudi Arabia are examined in this article. It looks at what China does similar to and differently from each partner, focusing on the supposed guiding principles of non-interference and economic cooperation. The research highlights Saudi Arabia and Iran's crucial roles in China's Belt and Road Initiative (BRI) by outlining the diplomatic maneuver’s, economic agreements, and energy collaborations that Beijing forges with the two nations. Analysis of China's Strategies in Comparison: Maintaining Neutrality in Diverse Interests while Balancing Saudi Arabian and Iranian Geopolitics Aside from the country's political and security issues, the world's rising superpower offers a chances for strategic partnerships, economic growth, and investment. The article examines China's long-term strategic objectives in the area with an emphasis on increased influence and cooperation. The article explores the wider geopolitical ramifications for Middle Eastern stability and international relations of China's strengthening relations with Saudi Arabia and Iran. It emphasizes China's function as a regional stabilizing force and draws attention to the possibility of changes in regional power dynamics and international strategic alignments. China's aspirations to become a global power are becoming more apparent through its interactions with Saudi Arabia and Iran, which will have a big impact on international relations and world stability.

Understanding the Decline of the US Dollar: Key Factors and Implications

This paper mainly focuses on the declining dominance of US dollar especially in the recent century and the role of different factors in this phenomenon. Recently decline is seen in the power of US dollar. The global dollar reserves faced so much pressure in recent times. Within two decades a sharp decline is seen in US dollar share of global currency reserves. This paper starts with the review on the factors that are causing the decline of US dollar. Many internal and external factors are causing this decline in dollar’s hegemony. These factors include external factors like de-dollarization, rise of other currencies like renminbi, euro, rise of China as a global power, rise of digital currencies, geopolitical risks, US sanctions on the Russia etc. and many internal factors like monetary policy given by US central bank, rising prices or inflation, demand for currency, economic growth, export prices, increasing federal debt etc. Countries mainly BRICS countries are moving towards de dollarization by proceeding their trade in their local currencies or currencies other than dollar, similarly rise of China as a big economic power also fastening this process as China increasing the scope of its renminbi, digital currencies also replacing paper currency effecting dollar’s hegemony, US sanctions on countries like Russia, Iran etc. also forcing states to move towards other banking systems. Likewise, US internal factors like inflation is on 40 years peak and federal debt rise up to 110% of GDP, economic growth is declining. These internal and external factors speeding up this process. As major world trade is still happening in dollar so decline in its dominance has a major impact on the global financial system. So, to study about its declining phenomenon is very important and this research mainly analyze on this declining trend of US dollar. The paper also looked at the short history of dollar that how it became the paper currency and how it emerged as main currency of the world. At the last of paper, I also talked about whether the decline of dollar is imminent? which is an important question asked by different economists and political analysts. These observations hint how the dollar’s hegemony is under threat.

A 46% PAE, 2.4-GHz Two-Stage Class E Power Amplifier Utilizing CMOS 0.13-µm Technology

A wireless device with a long battery life and great sensitivity becomes difficult to develop since there is a huge demand for low-power, low-cost wireless gadgets. The power amplifier (PA) is the most crucial part of radio frequency (RF) transceivers because of its massive power consumption. Consequently, in order to minimize power loss, a very effective and low-power consumption PA is needed. In this paper, high efficiency two-stage CMOS PA designed in 0.13-μm process for 2.4 GHz IoT transmitter applications is presented. The driver stage and power stage are the two stages that make up the two-stage topology of the proposed CMOS PA. To attain high efficiency and great power gain, a class E PA is used at the power stage. The LC matching network at the output is used for harmonic rejection filter at 2.4 GHz with an additional parallel capacitor helps for better harmonic rejection. In addition, a layout has been successfully designed and optimized. All the components in the proposed PA are designed on-chip. The pre-layout and post-layout simulations have been conducted to verify the proposed PA's performance. The pre-layout simulation of the proposed PA can deliver 19.19 dBm output power and 45.2% PAE at 2.0 V power supply into a 50-Ω load. On the other hand, the proposed PA produced an output power of 17.33 dBm and 46% PAE, according to the results of the post-layout simulation with a similar power supply of 2.0 V. The chip area for the proposed layout design is 1.05 mm2.

Great Power Politics and United States’ Withdrawal from Afghanistan

On October 7, 2002, the United States (US) started their military operation in Afghanistan to seek Osama bin Laden, the leader of Al Qaeda (AQ) who was responsible for the September 11, 2001, terror attacks commonly referred to as the 9/11 attacks. US military operations in Afghanistan, however, remained active after Osama bin Laden was killed. In February 2020, the US signed an agreement with the Taliban, who provided sanctuary for Osama bin Laden and AQ, which practically ended their military operation in Afghanistan. This article seeks to explain why the US decided to sign an agreement with the Taliban even though both AQ and the Taliban are still in operation. This article argues that the US decision to sign the agreement and withdraw from Afghanistan is due to the need to reallocate resources as part of their retrenchment policy. Keywords: Great Power Politics, Retrenchment, Withdrawal, the United States, Afghanistan, Al Qaeda, Taliban Pada tanggal 7 Oktober 2001, Amerika Serikat (AS) memulai operasi militer di Afghanistan untuk mencari Osama bin Laden, pemimpin Al Qaeda (AQ) yang menjadi otak (mastermind) serangan teror 11 September 2001 atau dikenal sebagai serangan 9/11. Meski demikian, operasi militer AS di Afghanistan tidak berhenti setelah Osama bin Laden terbunuh. Operasi militer AS di Afghanistan terus dipertahankan hingga mereka memutuskan mundur dari negara tersebut setelah penandatanganan kesepakatan damai dengan Taliban di Doha pada bulan Februari 2020. Tulisan ini mempertanyakan mengapa AS mundur dari Afghanistan meski tujuan yang ingin mereka sasar di negara tersebut belum tercapai. AQ maupun Taliban, kelompok yang memberikan perlindungan bagi AQ, masih tetap ada dan beroperasi. Tulisan ini berargumen bahwa keputusan AS tersebut terkait dengan adanya kebutuhan untuk mengalihkan alokasi sumber daya sebagai bagian dari kebijakan retrenchment. Kata-kata Kunci: Pertarungan Negara Besar, Retrenchment, Penarikan Mundur, Amerika Serikat, Afghanistan, Al Qaeda, Taliban

Theorizing Interreligious Relations

Abstract This article is an attempt to think through how interreligious relations might be theorized. It will show how conventional assumptions about interreligious relations can be traced to colonial understandings of the category religion, which determine what we classify as interreligious. I argue that interreligious relations, as we understand it today, developed through the rise of secular nationalism, when religion and politics were purportedly separated as a means of reordering European power structures aligned with Christianity during the formation of the modern nation-state. This rearrangement of power gave rise to Christian ecumenism, which helped pave the way for an evolving secular governance that eventually developed into multicultural pluralist societies in a postcolonial world. This article shall demonstrate how the assumptions that underlie contemporary interreligious relations have little to do with the relationships of people with different religious identities, as one might expect, but instead serve to promote national narratives of pluralism that uphold the liberal ideologies authorizing Western multicultural societies today.

Instrumentation for TMS‐EEG Experiment: ArTGen and a Custom EEG Interface

ABSTRACTIn transcranial magnetic stimulation (TMS) and electroencephalography (EEG) experiments, two researchers typically collaborate in the lab. This study addresses the challenge a single researcher faces in managing the TMS experiment's timing while operating the TMS coil. It introduces the Arduino Trigger Generator (ArTGen) to remotely control the timing of TMS experiments using a footswitch pedal. Moreover, a bespoke printed circuit board (PCB) is designed to interface the eegoMylab amplifier with off‐the‐shelf EEG caps. The ArTGen facilitates accurate timing of the TMS stimulator's inter‐pulse intervals (IPIs) through a footswitch pedal, enhancing researchers' control over TMS‐EEG experiments. The PCB interface provides a cost‐effective tool to extend the functionality of the eegoMylab amplifier. The integration of our PCB interface has been validated in a custom TMS‐EEG setup by analyzing TMS‐evoked potentials (TEPs), global mean field power (GMFP), butterfly plots, and event‐related spectral potentials (ERSPs). The PCB reliably preserved EEG signal integrity, ensuring accurate data acquisition. Thorough channel‐wise consistency checks across components confirmed data accuracy. ArTGen's portability and footswitch feature streamline experimental control, aiding TMS‐EEG research and clinical applications. Moreover, our PCB resolves compatibility between the eegoMylab amplifier and the Waveguard EEG cap by extending the amplifier to connect to off‐the‐shelf EEG caps. The ArTGen serves as a robust remote control tool for TMS stimulators, while our PCB interface presents a solution for integrating a customized TMS‐EEG setup. This study addresses the gap in existing TMS‐EEG research by introducing innovative technological enhancements that not only augment experimental flexibility but also streamline procedural workflows.

Geopolinomic codes: Territorial and discursive practices of connectivity networks of political economy

AbstractAfter the collapse of the Soviet Union in the 1990s, the global power structure entered a period of geopolitical transition. An evolved vision in the twenty‐first century shows the arrival of the geopolinomic order based on the combination of economic, political and territorial codes. Geopolinomic codes, in synergy with the global political economy, regulate the territorial and infrastructural arrangement of the world order in periods of geopolitical transition between hegemonic and emerging powers. Spatialization of power politics requires going through a set of geopolitical representations and this adds a thin discursive layer to the territorial hegemonic order. I argue that the development of geopolinomic codes allows for a more significant infusion of political economy through the centrality of territorial communication networks. A country with more manoeuvring power in adjusting geopolinomic codes and its triple levels can change the balance of global power structures in its favour.

Effects of different ratios of flexible links and rigid structures in side chains on membrane properties for HT-PEM applications

A series of grafted polybenzimidazoles with ratios of flexible links and rigid structures in side chains based on amino polybenzimidazole (AmPBI) was successfully prepared by simple N-substitution reaction. Due to the adequate number of amino groups on the AmPBI backbone, sufficient N–H sites reduce consumption of imidazole group during grafting reactions, while simultaneously elevating the number of proton transfer site. The grafted polybenzimidazole membranes with ratios of flexible links and rigid structures in side chains have excellent properties especially in the phosphoric acid (PA) uptake, pretty swelling ratio and proton conductivity. Importantly, PA uptake, swelling ratio, mechanical property, proton conductivity and power density can be controlled by changing the ratios of flexible links and rigid structures. The grafted membrane (AmPBI-P3) with the longer flexible link in the side chain shows a low swelling ratio of 128.62%, which is lower than that of other AmPBI-PX and AmPBI. Moreover, AmPBI-P3 shows a high proton conductivity of 126.9 mS cm−1 which is about 1.74 times higher than pure AmPBI (73.1 mS cm−1) and still reaches 91.4 mS cm−1 at 180 °C after the PA retention capacity test under 160 °C/0%RH for 240 h. A great power density of 738.5 mW/cm2 at 180 °C with dry H2–O2 and no backpressure is impressive among many reported membranes.

Chinese Re-Examinations of Russia? The Strategic Partnership in the Wake of Russia’s War Against Ukraine

ABSTRACT This article asks whether Russia’s full-scale invasion of Ukraine has prompted a reevaluation within the Chinese expert community on China’s strategic partnership with Russia. This article examines how Chinese experts and academics assess the impact of the war on the partnership and Russia’s future role for China with regard to: security and military affairs; economy and technology; and global governance and regional interaction. Chinese analysts recognize that the war has put China in a difficult situation. Several voices express caution and calls to avoid becoming too closely associated with Moscow are prevalent, not least as Chinese experts view China and Russia diverging in the future on issues concerning the global order. Moreover, Russia’s development prospects are considered dim, which in turn affects the potential for concrete cooperation with China. Chinese assessments advocate for selective engagement with Russia, largely on Chinese terms as the balance of power continues to shift in China’s favor. Nonetheless, this article finds that the Chinese expert community overall assesses that the basic tenet for maintaining the strategic partnership remains unchanged. Crucially, under current US global dominance, Russia is considered a key partner to jointly counter-balance American global power and regional influence.

The implications of the Indo-Pacific Partnership for Maritime Domain Awareness (IPMDA) in the South China Sea: A Chinese perspective

The emergence of China as a major power and its adjustment of foreign policy have raised concerns in the U.S. The Quad, led by the U.S., aims to counterbalance China’s growing influence in East and Southeast Asia, and the Indo-Pacific Maritime Domain Awareness (IPMDA) acts as an important component of its strategy. However, this article notes that the endeavor faces significant challenges, including legal and geopolitical risks, as well as economic and technical limitations. Intelligence-gathering activities may infringe upon the sovereign rights and jurisdiction of coastal states, especially within disputed maritime areas. Cooperative enforcement under IPMDA can raise legal questions concerning the transfer of maritime jurisdiction under UNCLOS to non-contracting parties. China perceives the IPMDA initiative as a threat posed by the Quad. The Chinese government is concerned that it could spark renewed criticism of its fishing industry and strain diplomatic ties with neighboring countries. China’s response could entail the establishment of alternative mechanisms and increased transparency in maritime activities. Against the backdrop of intensifying competition between the U.S. and China and ongoing disputes in the South China Sea, the IPMDA could exacerbate existing tensions in the SCS area. The exclusivity of the IPMDA mechanism may not serve the best interests of maritime security and prosperity in the Asia-Pacific region. In this context, China is encouraged to play a more constructive role in defusing tensions.

Quantifying power regulation characteristics in pump mode of variable‐speed pumped storage unit with DFIM

AbstractPumped storage plants (PSPs) play an important role in renewable energy consumption in power systems. Variable‐speed technology is a new and critical direction for the development of PSPs. In pump mode, variable‐speed pumped storage units (VSPSUs) have wider power regulation ranges and more flexible power responses than fixed‐speed pumped storage units (FSPSUs); however, the corresponding quantification study of VSPSUs is rare. Therefore, this study aims to quantify the static and dynamic power regulation characteristics of VSPSU in pump mode. First, the modeling of the fast speed control strategy of VSPSU in pump mode is improved. Then, the power regulation range of the VSPSU is explored. The factors (i.e., power command, governor, and converter) affecting the power response rapidity are quantified through the engineering case of a variable‐speed PSP adopting the doubly fed induction machine. Accordingly, suggestions on the settings of the parameters are provided. Quantification results show that parameter tuning based on this study effectively solves the problem of low regulation rate caused by great power fluctuations under typical power regulation cases in pump mode. This VSPSU has the fastest regulation rate of 13.75%/s when adjusting 40% power. This study could provide technical support to the practical operation of VSPSU.

On the Dual International Identity of Contemporary China

Since the beginning of the 21st century, one of the central research questions for Chinese IR scholars has been the definition, justification and conceptualization of China’s international identity. This was due both to the discussions in the Chinese academic community about China’s peaceful rise, caused by the rapid growth of China’s material power, and to the “constructivist turn” in the development of IR as a discipline in China. Understanding China’s international identity is important not only for China itself as a way of understanding “itself” and “others”, but also for the world community, since the self-positioning of a state reveals its national interests, aspirations, foreign policy strategy and behavior. From the founding of the People’s Republic of China in 1949 to the end of the 1990s, when analyzing its foreign policy self-positioning, it was always possible to identify a dominant international identity. In the 1950s it was a pronounced international identity of the PRC as a socialist country, in the 1960s–1980s as a third world country, since the 1990s as the largest developing country. However, since the second half of the 1990s, China has started to reveal its identity as a responsible great power while simultaneously maintaining its identity as a developing country. The use of two international identities by China for almost three decades and the intention repeatedly emphasized by the Chinese leadership to maintain self-positioning as a developing country for a long time allow us to conclude that China’s dual international identity is not a reflection of the transition period of China’s development, but represents a complex phenomenon that requires conceptualization. The purpose of this article is to reveal the phenomenon of contemporary China having a dual international identity or, in other words, simultaneously two dominant international identities that determine China’s actions on the global stage. The author intended to reveal, based on an analysis of Chinese academic publications, the Chinese vision of the phenomenon of dual international identity.

Power and place: Uncovering the politics of global medical education.

Politics is characterised by power relations, and the deployment of power is inescapably political. In an increasingly globalised and interconnected modern world, politics is shaping the field of medical education more than ever before. Global frameworks that classify peoples and places are political tools that are fundamentally shaped by hegemonic knowledge systems. Despite this, they continue to form the basis for global thinking and practices, including in medical education. Political analysis can help to expose and challenge such thinking. To better understand impacts of globalisation in medical education, we explore the previously under-examined political dimensions that underpin it, focusing particularly on deconstructing power relations. We situate our analysis of global medical education in political terms, including through examination of ideology, economics, market and the enduring effects of colonialism. We interrogate the construct of the Global South (GS), considering the geopolitical and historical ideas that have enabled it to be widely propagated. We go on to examine the consequences of the GS construct in medical education and consider what this tells us about how power is enacted in the field. In analysing the politics of global medical education, we shed light on how power is exerted and draw attention to forces that permit and enable trends, policies and positions. Notwithstanding the emancipatory rhetoric that has been associated with the GS construct, we highlight its reductive potential and argue that it can lead to an oversimplification of power relations and vested interests. Given the growing recognition that educational approaches do not transfer well across countries and cultures, we encourage the medical education community to consider why ideas from more dominant countries continue to be imitated so routinely. In doing so, we urge them to use political lenses to recognise the influence of multiple complex and interconnected forces of global power that shape all aspects of medical education.

Research on Photovoltaic Maximum Power Point Tracking Control Based on Improved Tuna Swarm Algorithm and Adaptive Perturbation Observation Method

In situations where photovoltaic (PV) systems are exposed to varying light intensities, the conventional maximum power point tracking (MPPT) control algorithm may become trapped in a local optimal state. In order to address this issue, a two-step MPPT control strategy is suggested utilizing an improved tuna swarm optimization (ITSO) algorithm along with an adaptive perturbation and observation (AP&O) technique. For the sake of enhancing population diversity, the ITSO algorithm is initialized by the SPM chaos mapping population. In addition, it also uses the parameters of the spiral feeding strategy of nonlinear processing and the Levy flight strategy adjustment of the weight coefficient to enhance global search ability. In the two-stage MPPT algorithm, the ITSO is applied first to track the vicinity of the global maximum power point (MPP), and then it switches to the AP&O method. The AP&O method’s exceptional local search capability enables the global MPP to be tracked with remarkable speed and precision. To confirm the effectiveness of the suggested algorithm, it is evaluated against fuzzy logic control (FLC), standard tuna swarm optimization (TSO), grey wolf optimization (GWO), particle swarm optimization (PSO), and AP&O. Finally, the proposed MPPT strategy is verified by the MATLAB R2022b and RT-LAB experimental platform. The findings indicate that the suggested method exhibits improved precision and velocity in tracking, efficiently following the global MPP under different shading conditions.

Foreign Policy of India as the Reflection of Change in its Ruling Elite

The article examines the changes in the formulation, prioritisation and implementation of India’s foreign policy objectives as a result of a significant renewal of its political elite, triggered by the economic reforms that began in the 1990s. It is argued that India’s ruling elite is now largely identical to its political elite, whose mindset, although considerably younger and better educated, is more than ever defined by its self-identification with traditional values, which are religious and, for the vast Hindu majority, caste-based. At the same time, the composition of India’s elite has broadened during the reform years, mainly through the inclusion of middle and even lower castes in the traditional hierarchy. Many of its representatives tend to associate the strengthening of the country with a return to the “correct” cultural and civilisational basis which, in the centuries before foreign conquest, gave India what the y saw as its natural primacy in the world. The main change is the emergence of a sense of self-confidence among the elite, on which the so-called “new nationalism” of the “man of the people”, the current Prime Minister N. Modi, is based. Drawing on his statements, speeches by Foreign Secretary S. Jaishankar, and articles by Indian and Russian scholars, the author shows the innovations introduced by the Prime Minister in promoting India’s core national interests in a changing world. The article examines the creation of India’s own sphere of influence within the framework of the new Indo-Pacific strategy, the combination of cooperation and competition in relations with China, the reasons for the dynamic expansion of interaction with the United States and the “red lines” involved, the motives for developing a particularly privileged strategic partnership with Russia and for using multilateral formats, and the return to India’s agenda of the task of gaining the status of the main voice of the Global South. It is concluded that approaches to the imperative of building a multipolar world order “in which India would be a strong pole”, based on the priority goal of establishing for it the status of a great power and a global actor in world politics, create historic opportunities for increasing Russian-Indian interaction.

Chess Game Rook‐Icon Movement‐Based Photovoltaic Array Reconfiguration for Higher Shade Dispersion and Improved Global Power Peaks Under Partial Shading Conditions: An Experimental Study

Solar photovoltaic (PV) system generates low power because of nonuniform sun irradiation compared to standard test conditions. Partial shading conditions (PSCs) can arise from various factors, with passing clouds, trees, telecommunication towers, bird droppings, and similar elements being among the most prevalent causes. Under the shading scenario, multiple global and local maxima power points exist on the P–V curves. Herein, the chess game rules for the “Rook” icon are followed to attain the optimal placement of integer numbers (1–9) in the 9 × 9 size game puzzle matrix. The integer number‐based game puzzles such as Su‐Do‐Ku, symmetric matrix, and proposed Rook's movement‐game theory (RMGT) to rearrange the PV modules in arrays are investigated and compared with the standard arrangements such as series‐parallel, total‐cross‐tied during PSCs. The suggested RMGT puzzle‐based arrangement is able to achieve higher power at global maximum power point, performance enhancement, fill factor, and low power loss. As a result, the experimental study proves the superiority of RMGT configuration compared to conventional methodologies under the shading scenarios. The proposed RMGT‐based PV array is tested and obtained the performance higher side as, , , , and compared to existing reconfiguration methodologies.

The Combination of Hedging and Rules of Great Power Rivalry——Taking the Example of Vietnam in Sino-US Rivalry

The competition between China and the United States for dominance in global governance is intensifying. In such an international context, strategically significant small states often adopt a hedging strategy to stay neutral amidst the rivalry of major powers. This paper aims to study the phase-specific characteristics and overall trends of hedging, and to detail the phase-specific motivations behind it. Contrary to previous academic views, this paper argues that hedging is not merely a passive balancing act for small states, but an active pursuit of maximizing economic and security interests. This paper concludes that hedging represents a cyclical trend divided into three stages. In addition to the manipulations of small states pursuing their own interests, the competition rules between major powers also influence the trend of hedging. This study is beneficial for 3further understanding the mindset of small states in employing hedging strategies and promotes the internalization of hedging theory in the field of international relations. It also provides insights into China's decision-making in its diplomatic relations with Vietnam.

The European Union’s climate policy towards Ukraine: normative power Europe in action?

The EU’s aspirations for leadership are also evident in regional and global climate policy, especially given the urgency of the problem of rising global temperatures. Since 2014, EU member states have been actively involved in shaping the organisation’s legislative framework on climate policy. This article set out to determine when the EU gained the capability to act as a normative green power and to assess whether the EU acted as an established normative power in forming a climate partnership with Ukraine from the 1990s to the first half of 2024. The research is organized into two chapters. Chapter 1 explores two dimensions of the behavioral logic of different foreign policy actors: norm compliance and norm diffusion. Normative actors of foreign policy, unlike non-normative ones, are guided by the logic of appropriateness in the process of compliance with norms and the logic of argumentation in the process of diffusion of norms. Chapter 2 identifies the periods when the EU complied with climate norms according to the logic of appropriateness and spread climate norms in Ukraine according to the logic of arguing. After analyzing two dimensions of the EU’s behavioral logic in detail, it can be concluded that it was only after 2019 that the EU began to act as an established normative power in building a climate partnership with Ukraine. In other words, from this point onward, the EU both complied with climate norms according to the logic of appropriateness and diffused them in Ukraine according to the logic of arguing. The European Climate Law, enacted in 2021, further demonstrated the EU’s dedication to complying with climate norms based on the logic of appropriateness, establishing legislative obligations to achieve climate neutrality by 2050.

Türkiye’s Military Base in Somalia: A Case Study

At the present stage the Republic of Türkiye is all the more actively claiming the role of a regional leader and at the same time, using the favourable geopolitical position at the junction of two civilizations, seeks to strengthen influence in global politics. The statehood of independent states is impossible without strengthening their own security, and that allows for the development of international military dialogue. Türkiye as a world power is to restore its prosperity from the times of the Ottoman Empire. Best evidence is the creation of Turkish military bases beyond its national borders. Moreover, such actions of the Turkish leadership are considered not only a political ambition but also a pragmatic calculation. First overseas military base of Türkiye in modern times was created in one of the most turbulent countries in the world – Somalia. Currently, Türkiye has a military presence in Somalia. Hence, this study examined the main stages of bilateral relations between Türkiye and Somalia. Relations between the two countries have passed a certain historical path of development and have been characterized by periods of activation revival also stagnation. It was concluded that despite the fact that political, economic and military cooperation between Türkiye and Somalia had huge potential, there were some of constraining factors affecting their further development.

Effects of feedback-free starburst galaxies on the 21-cm signal and reionization history

ABSTRACT Different star formation models at Cosmic Dawn produce detectable signatures in the observables of upcoming 21-cm experiments. In this work, we consider the physical scenario of feedback-free starbursts (FFB), according to which the star formation efficiency (SFE) is enhanced in sufficiently massive haloes at early enough times, thus explaining the indication from the JWST for an excess of bright galaxies at $z \ge 10$. We model the contribution of FFBs to popII SFE and compute the impact these have on the 21-cm global signal and power spectrum. We show that FFBs affect the evolution of the brightness temperature and the 21-cm power spectrum, but they only have a limited effect on the neutral hydrogen fraction. We investigate how the observables are affected by changes in the underlying star formation model and by contribution from popIII stars. Finally, we forecast the capability of next-generation Hydrogen Epoch of Reionization Array (HERA) to detect the existence of FFB galaxies via power spectrum measurements. Our results show the possibility of a significant detection, provided that popII stars are the main drivers of lowering the spin temperature. Efficient popIII star formation will make the detection more challenging.