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With the increasing heat dissipation of electronic devices, the cooling demand of electronic products is increasing gradually. A water-cooled microchannel heat exchanger is an effective cooling technology for electronic equipment. The structure of a microchannel has great impact on the heat transfer performance of a microchannel heat exchanger. The purpose of this paper is to analyze and compare the fluid flow and heat transfer characteristic of a microchannel heat exchanger with different reentrant cavities.

The three-dimensional steady, laminar developing flow and conjugate heat transfer governing equations of a plate microchannel heat exchanger are solved using the finite volume method.

At the flow rate range studied in this paper, the microchannel heat exchangers with reentrant cavities present better heat transfer performance and smaller pressure drop. A microchannel heat exchanger with trapezoidal-shaped cavities has best heat transfer performance, and a microchannel heat exchanger with fan-shaped cavities has the smallest pressure drop.

The fluid is incompressible and the inlet temperature is constant.

It is an effective way to enhance heat transfer and reduce pressure drop by adding cavities in microchannels and the data will be helpful as guidelines in the selection of reentrant cavities.

This paper provides the pressure drop and heat transfer performance analysis of microchannel heat exchangers with various reentrant cavities, which can provide reference for heat transfer augmentation of an existing microchannel heat exchanger in a thermal design.

RF transceiver module is considered a vital part of any wireless communication system. This module consists of two important parts the RF transceiver and analog-to-digital converter (ADC). Usually, both these parts – RF transceiver and ADC – are used to enhance the perspective of size and power. The data processing in 4G communication makes hurdles and need research attention to make it faster and smaller in size. Accuracy and fast processing are the critical challenges in the modern communication system.

After theoretical and practical investigations, this research work proposes key new techniques for the RF transceiver module. These techniques will make RF transceiver small, power-efficient and on the other hand, make dual SAR-ADC more effective as well. The proposed design has no intermediate frequency where the RF transceiver is reduced its major blocks from five to four, which includes crystal oscillator, phase lock loop, power amplifier and low noise amplifier. Moreover, the shared circuitry is introduced in the architecture of the SAR-ADC for the production of dual outputs, specifically in bootstrapped switch and comparator.

The miniaturized RF transceiver and SAR-ADC are well tested separately before the plantation on the printed circuit board (PCB). The operating voltage and frequency of the RF transceiver module are 1.2 V and 5.8 GHz, where the sampling rate, bandwidth and output power are 25 MHz, 200 MHz and 5 dBm, respectively. The core area of the PCB is 58.13 mm². The bandwidth efficiency is 93% using surface acoustic wave less transmitter. The circuit is based on the library of 90 nm CMOS technology.

The entire circuit is highly synchronized with the input and reference clocks to avoid self-interference.

This study uses the Vector Error Correction Model (VECM) to forecast ex post changes in earning and stock prices of six major DOW companies as well as of the S&P 500 market index. Compared to ARIMA and GARCH models, results from four decades of data are supportive of the forecasting ability of the VECM process.

Cooperation in agriculture and agricultural products trade is a new driving force for Sino-Russian cooperation in economy and trade in recent years. Driven by the interests and needs of both countries, a Free Trade Zone (FTZ) on the Chinese territory facing Russia, the Heilongjiang FTZ, has been established, and agricultural cooperation has attracted much attention within the FTZ framework. This chapter aims to analyze and explain the prospects of Sino-Russian agricultural cooperation under the framework of the Heilongjiang FTZ based on the current situations of cooperation. The author concludes that the Heihe and Suifenhe Areas in Heilongjiang FTZ are developed with a focus on Sino-Russian agricultural cooperation. This chapter is innovative because it combined the traditional research perspective on Sino-Russian agricultural cooperation with that under the FTZ framework. The author thinks that to facilitate the cooperation between the two countries in agriculture under the FTZ, the two governments must cooperate more extensively. Besides, they need to discuss the establishment of infrastructures like a joint agricultural product R&D centre and a digital development centre for agriculture. Meanwhile, the schemes of dispute settlement and risk-sharing should be addressed as well.

This study empirically explores the intraday price discovery mechanism and volatility transmission effect between the dual-listed Indian Nifty index futures traded simultaneously on the onshore Indian exchange, National Stock Exchange (NSE) and offshore Singapore Exchange (SGX) and its spot market by using high-frequency data.

This study applies the vector error correction model to analyze the lead-lag relationship in price discovery among three markets. The contributions of individual markets in assimilating new information into prices are measured using various measures, Hasbrouck's (1995) information share, Lien and Shrestha's (2009) modified information share and Gonzalo and Granger's (1995) component share. Additionally, the Granger causality test is conducted to determine the causal relationship. Lastly, the BEKK-GARCH specification is employed to analyze the volatility transmission.

This study provides robust evidence that Nifty futures lead the spot in price discovery. The offshore SGX Nifty futures consistently ranked first in contributing to price discovery, followed by onshore NSE Nifty futures and finally by the spot. Empirical results also show unidirectional causality and volatility transmission from Nifty futures to spot, as well as bidirectional causal relationship and volatility spillovers between NSE and SGX Nifty futures. These novel findings provide fresh insights into the informational efficiency of the dual-listed Indian Nifty futures, which is distinct from previous literature.

These findings can potentially help market participants, policymakers, stock exchanges and regulators.

Unlike previous studies in this area, this is the first study that empirically examines the intraday price discovery mechanism and volatility spillover between the dual-listed futures markets and its spot market using 5-min overlapping price data and trivariate econometric models.

The purpose of this study is to address the extended travel time caused by dwelling time at stations for passengers on traditional rail transit lines. To mitigate this issue, the authors propose the “Non-stop” design, which involves trains comprised of modular vehicles that can couple and uncouple from each other during operation, thereby eliminating dwelling time at stations..

The main contributions of this paper are threefold: first, to introduce the concept of non-stop rail transit lines, which, to the best of the authors’ knowledge, has not been researched in the literature; second, to develop a framework for the operation schedule of such a line; and third, the author evaluate the potential of its implementation in terms of total passenger travel time.

The total travel time was reduced by 6% to 32.91%. The results show that the savings were more significant for long commutes and low train occupancy rates.

The non-stop system can improve existing lines without the need for the construction of additional facilities, but it requires technological advances for rolling stock.

To eliminate dwelling time at stations, the authors present the “Non-stop” design, which is based on trains composed of locomotives that couple and uncouple from each other during operation, which to the best of the authors’ knowledge has not been researched in the literature.

The purpose of this paper is to analyze the conformity of the impact of corporate finance decisions on market value with the basic theoretical approaches in the two emerging economies, which show great similarities in terms of the economic structures, and to examine the results obtained by determining how these decisions affect market value comparatively.

In this study, the effect of corporate finance decisions on market value is tested empirically with panel data analysis method by using data of 274 real sector firms traded in BIST and 249 firms in BOVESPA industry index, between 2010 and 2014.

The analysis results show that the increase in the borrowing level of firms operating in both countries reduces the market value; the increase in the level of profitability in the firms has a positive effect on the market value. In addition, it is possible to say that the effect is different in terms of investment decisions for Turkish and Brazilian firms.

The limitations of the study are that the non-financial sectors between 2010 and 2014 in Turkey and Brazil including the company data, and the companies with missing years are removed from the data set. The findings show that more effective and balanced management of the variables by the financial manager affects these rates and have an impact on increasing the market value.

In this study, a fundamental subject in finance is addressed by analytical methodology and comparative tests for countries are conducted.

This study aimed to address a gap in subcontractor management by focusing on previously unexplored complexities surrounding subcontractor management in developing countries. While past studies concentrated on selection and relationships, this study delved into how effective subcontractor management impacts project success.

This study used the Bayesian Network analysis approach, through a meticulously developed questionnaire survey refined through a piloting stage involving experienced industry professionals. The survey was ultimately distributed among participants based in Accra, Ghana, resulting in a response rate of approximately 63%.

The research identified diverse components contributing to subcontractor disruptions, highlighted the necessity of a clear regulatory framework, emphasized the impact of financial and leadership assessments on performance, and underscored the crucial role of main contractors in Integrated Project and Labour Cost Management with Subcontractor Oversight and Coordination.

Previous studies have not considered the challenges subcontractors face in projects. This investigation bridges this gap from multiple perspectives, using Bayesian network analysis to enhance subcontractor management, thereby contributing to the successful completion of construction projects.

This paper aims to evaluate the separation and purification characteristics of flavonoids from polygonum cuspidatum (PC) extracts by using macroporous adsorption resins (MAR) mixed bed to improve the utilization rate of flavonoids.

Taking the separation performance of flavonoids as an evaluation index, the best MAR were screened from 31 sorts of MAR and combined the best MAR to form a MAR mixed bed for adsorption and separation of flavonoids.

By studying the separation conditions that affect flavonoids, the results showed that resin LZ-72 has best separation and purification effect on flavonoids under the optimal adsorption and desorption conditions, the purity of the obtained flavonoid compound reaches 82.50%, 2.66 times of the initial extract, and the recovery rate reaches 89.70%. Theoretical research results have shown that the adsorption of flavonoids by MAR conforms to the pseudo-second-order kinetics and Freundlich models.

Because the flavonoids in PC have great medicinal value, the purpose of this work is to develop a method of separating and purifying flavonoids from PC, which will provide a certain foundation for the development of medicine.

This contribution provided a novel way to separate flavonoids from PC. Under the optimal conditions, the content of flavonoids in the product was increased 2.66-fold from 31.01% to 82.50%, and the recovery yield was 89.70%.