Study on outage performance gap of two destinations on CR-NOMA network

Non-orthogonal multiple access (NOMA) and cognitive radio (CR) are promising for solving the severe spectral scarcity problem encountered by the next generation of wireless communication systems. This study aims to improve spectral efficiency at two secondary destinations by investigating a CR-NOMA network under situation of the perfect successive interference cancellation (SIC). We also derive the exact outage probability for secondary users. Furthermore, an approximate computation method is applied to indicate more insights. It is confirmed that the performance achieved together with performance gap among two users can be obtained due to different power allocation factors assigned to users

Desarrollo de la presión del sujetador: Sistema de medición con aire y sensor de presión

Introduction: This paper is the result of the research “Development of bra pressure measuring system using air pressure sensor” developed in the Ha Noi University of Science and Technology in 2019.  Proplem: The pressure of the bra on the human body affects the comfort of the wearer and the wearer's health. Therefore, bra pressure is one of the most important parameters taken into account when designing and manufacturing bras. Objective: To determine the pressure value of a bra, it is necessary to use a suitable pressure measuring device. Methodology: The device operates on the principle of resitive gas pressure sensor, with 8 measuring channels. The system is controlled by the computer via programming software in the Visual C language, measuring the pressure of the shirt on the position on the curved surface of the human body. Pressure values ​​and timed charts are displayed on the computer. The measuring device was tested with GE Druck DPI 610 pressure generator.  Results: Test results showed that the device has a sensitivity of 0.01 kPa, measuring range from 0.1to 10 kPa and an accuracy of 0.01 kPa. Conclusion: This measurement system is important for objectively assessing the pressure of the bra on the wearer.  Originality: This paper presents the results of research and design of the PB228 system when measuring the pressure of the bra on the wearer's body in static, dynamic and static-dynamic combined states.  Limitations: The accuracy of the device only applies in standard condition

Group Scheduling for MultiChannel in OBS Networks

Group scheduling is a scheduling operation of optical burst switching networks in which the burst header packets arriving in each timeslot will schedule their following bursts simultaneously. There have been many proposals for group scheduling (such as OBS-GS, MWIS-OS and LGS), but they consider mainly to schedule the arriving bursts which have the same wavelength on an output data channel. Another suggestion is GreedyOPT which considers the group scheduling for multichannel with the support of full wavelength converters, but it is not optimal. This article proposes another approach of group scheduling which is more optimal and has a linear complexity

Mobility Enhancement in Square Quantum Wells: Symmetric Modulation of the Envelop Wave Function

We present a theoretical study of the effects from symmetric modulation of the envelop wave function on quantum transport in square quantum wells (QWs). Within the variational approach we obtain analytic expressions for the carrier distribution and their scattering in symmetric two-side doped square QWs. Roughness-induced scattering are found significantly weaker than those in the asymmetric one-side doped counterpart. Thus, we propose symmetric modulation of the wave function as an efficient method for enhancement of the roughness-limited QW mobility. Our theory is able to well reproduce the recent experimental data about low-temperature transport of electrons and holes in two-side doped square QWs, e.g., the mobility dependence on the channel width, which have not been explained so far

The Channel-width Dependence of the Low-temperature Hole Mobility in Ge-rich Narrow Square Quantum Well Studied by the Band-bending Method

We employ the theory of band-bending effects to explain the channel-width dependence of the mobility of a two-dimentional hole gas (2DHG) in narrow square Si/Si$_{1-x}$Ge$_x$/Si quantum well at high Ge content. The numerical calculation of scattering mechanisms is shown in comparison with the ones from the previous computations. Our method enables a better quantitative description of recently measured data about the dependence of the 8 K mobility of holes in a Si/Si$_{0.2}$Ge$_{0.8}$/Si quantum well on the channel width varying from 25 - 70

Enhancing the capacity of tax authorities and its impact on transfer pricing activities of FDI en-terprises in Ha Noi, Ho Chi Minh, Dong Nai, and Binh Duong province of Vietnam

This study aims at discovering the relationship between the improvement in the capacity of tax authorities and its effect on the transfer pricing activities of foreign direct investment (FDI) enterprises in four provinces/cities of Vietnam: Ha Noi, Ho Chi Minh, Dong Nai, and Binh Duong province. These are the first localities in Vietnam to establish the Division of Transfer Pricing Inspectorate in local Tax Department, under the direction of General Department of Taxation of Vietnam. The paper then proposes a further study on how the tax authorities of Vietnam should improve their capacities to make FDI enterprises more compliant with the transfer pricing regulations in Vietnam. The authors deploy the method of quantitative research through collecting self-administered closed format questionnaires from people in charge of finance/accounting/transfer pricing of FDI enterprises operating in Ha Noi, Ho Chi Minh, Dong Nai, and Binh Duong province of Vietnam. The findings suggest that there was a strong probability that the capacity of tax authorities would impact on the transfer pricing activities of FDI enterprises in Ha Noi, Ho Chi Minh, Dong Nai, and Binh Duong of Vietnam. Vietnamese Government should enhance the capacity of the tax authorities; establish Transfer Pricing Inspectorate Division in all local Tax Departments of Vietnam. The authors believe that the improvement of tax officials’ capacity especially those in charge of transfer pricing auditing will prevent the FDI enterprises from transfer pricing manipulation, hence these enterprises will be more compliant to transfer pricing regulations of Vietnam. The most significant value of the study is to support Vietnamese policymakers, especially those in the field of Finance (Ministry of Finance, General Department of Taxation) to improve their capacity when carrying out transfer pricing audit in FDI enterprises. The more transparent and aggressive the tax officials are, the better these enterprises follow the regulations

Ownership Concentration and Accounting Conservatism: The Moderating Role of Board Independence

The purpose of this study is to examine the moderating effect of board independence on the relationship between ownership concentration and accounting conservatism. Using fixed-effect regressions for a sample of 165 Vietnamese listed companies from 2007 to 2017, the results revealed that the proportion of outstanding shares owned by the largest shareholder is negatively associated with accounting conservatism and board independence plays a moderating role in this relationship. Our results are robust after applying alternative measures of the largest ownership and correcting for potential endogeneity using fixed-effects regression with instrumental variables. Overall, our evidence shows that firms with concentrated ownership should keep a high non-executive ratio to maintain accounting conservatism. In other words, increasing the number of non-executive directors on boards in firms with a substantial proportion of shares held by the largest shareholder is likely to strengthen the information environment, giving financial reporting more credibility.JEL Classification: G30; G32. Doi: 10.28991/ESJ-2023-07-01-07 Full Text: PD