User System Research Articles

Postmenopausal hormone therapy and mortality before and after the Women’s Health Initiative study

Weighing risks and benefits of postmenopausal hormone therapy (HT) has proven a balancing act. We aimed to investigate the association between HT and mortality before and after the 2002 publication from the Women’s Health Initiative (WHI) study. This publication found that the risk of using HT outweighted the benefits, and thus it caused a marked reduction in systemic HT user prevalence. The 2002 WHI publication may also have caused a change in the subsequent HT user profile, as HT is no longer recommended in the prevention of chronic diseases. This cohort study included two populations followed from 1995: A 5% random sample of female singletons from the Danish general population (n = 52,388) and a sample of Danish female twins (n = 15,261). HT use was evaluated in 1995, 2000, 2005, and 2010. The association between HT, education, and mortality was investigated and controlled for potential unobserved familial confounding in a within-pair analysis. Singletons aged 56–75 using systemic HT in 2000 had a lower mortality compared to non-users (hazard ratio (HR) 0.83, 95% confidence interval (CI) 0.78–0.89). In 2005, the mortality was like that of the background population for this age group (HR 1.02, 95% CI 0.94–1.11). Recently postmenopausal twins showed a similar tendency. Systemic HT users, who had switched to local HT by 2005, had a substantially lower mortality than non-users (HR ranging from 0.42 to 0.67 depending on age group). In conclusion, we found that the prevalence of systemic HT use declined after 2002, and systemic HT users’ mortality changed from lower before 2002 to similar to that of the background population after 2002. This indicates that the healthiest users decided to either drop systemic HT or switcted to local HT, as recommendations changed following the WHI publication.

An optimal detection of android malware using dynamic attention-based LSTM classifier

In today’s world, Android has become the most significant and standard operating system for smartphones. The acceptance of the rapidly growing android system has outcome in a significant enhancement in the number of malware on comparing earlier days. There were several antimalware programs that are designed efficiently for protecting the sensitive data of the user in a mobile system from the occurrence of such attacks. Detection of malware system based on deep learning model along with the use of optimization technique is presented in this work. Initially, android malware dataset input is acquired and the normalization process is done. The feature selection is carried along with the optimization technique Recurrent Tuna Swarm Optimization. By this, an optimal selection of features can be attained.

User Selection Methods for Overcoming Growing Number of Served Users in Massive MIMO Systems

Massive MIMO is dominant in the current wireless communication systems. Massive MIMO system uses a massive number of antennas to serve multi-users simultaneously. The growth of served users in the system will increase the interference between them and affect the system’s performance. To maintain the qualified service for the growing number of users, user selection techniques can be used to separate users into groups to be served well. This paper proposes three user selection methods named Mean Step User Selection (MSUS), Second Null User Selection (SNUS), and Interference Threshold User Selection (ITUS) methods. These three user selection methods aim to serve users with the best possible performance. The performance of these proposed user selection methods will be evaluated and compared with the performance of the system without selection and with the system using other user selection methods such as Random User Selection (RUS), Semi-orthogonal User Selection (SUS), and Inter-Channel Interference Based Selection (ICIBS) methods. The simulation shows that the proposed MSUS, SNUS, and ITUS methods provide an improvement in the spectral efficiency of 75.39%, 92.13%, and 153.71% when compared with the system without the selection method. The proposed user selection methods also improve performance compared to other user selection methods.

A Spectrum Occupancy Model for Primary Users in Cognitive Radio Systems

A Spectrum Occupancy Model for Primary Users in Cognitive Radio Systems

Constructions of asymptotically optimal codebooks with respect to Welch bound and Levenshtein bound

<p style='text-indent:20px;'>Codebooks with small maximum cross-correlation amplitudes are used to distinguish the signals from different users in code division multiple access communication systems. In this paper, several classes of codebooks are introduced, whose maximum cross-correlation amplitudes asymptotically achieve the corresponding Welch bound and Levenshtein bound. Specially, a class of optimal codebooks with respect to the Levenshtein bound is obtained. These classes of codebooks are constructed by selecting certain rows deterministically from circulant matrices, Fourier matrices and Hadamard matrices, respectively. The construction methods and parameters of some codebooks provided in this paper are new.</p>

Generic Construction of Black-Box Traceable Attribute-Based Encryption

Attribute-based encryption (ABE) has been widely used to provide fine-grained access control to encrypted data in cloud computing. However, in practice, since the attributes are shared by multiple users in the ABE system, it is difficult to identify malicious users which intentionally but implicitly reveal their own ABE secret keys for some purpose. In recent years, a substantial amount of work focused on designing efficient tracing mechanisms to identify such misbehaving users on ABE. In this paper, we propose an efficient generic construction of black-box traceable ABE to identify the traitors. Our construction supports (public) adaptive black-box traceability and has short keys and short ciphertexts that are independent of the number of users. Technically, our construction relies on a generic transformation from any attribute-based inner-product functional encryption (ABIPFE) scheme to black-box traceable ABE system. Furthermore, to instantiate our generic construction from standard lattices, we propose the first lattice-based ABIPFE scheme, which is proven weakly selective secure in the standard model.

Analytic Distribution Design for Irregular Repetition Slotted ALOHA With Multi-Packet Reception

Associated with multi-packet reception at the access point, irregular repetition slotted ALOHA (IRSA) holds a great potential in improving the access capacity of massive machine type communication systems. This work investigates the packet repetition of the users in an IRSA-based random access system where the access point can simultaneously retrieve multiple packets in a slot. Specifically, we propose an analytical transmission probability distribution for IRSA with <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dual-packet reception capability</i> . In addition, the energy efficiency optimization in terms of the maximum number of replica is also presented. Numerical results show that using the proposed transmission distribution for the replica can achieve a significant higher throughput than the existing benchmark distributions. With optimized repetition rate, the energy efficiency of users can be also improved remarkably.

Cross-Chain Virtual Payment Channels

With the emergence of countless independent blockchain systems in recent years, cross-chain transactions have attracted considerable attention, and lots of solutions have been put forth by both industry and academia. However, most of the existing solutions suffer from either centralization or scalability issues. To mitigate these issues, in this paper, we propose the concept of cross-chain virtual payment channels, which allows two users in different blockchain systems to conduct limitless off-chain transactions with the help of an intermediate node, hence solving the centralization and scalability issues. Furthermore, as the intermediate node is only involved in the channel open and close operations, it further improves the efficiency of cross-chain transactions, and to a certain extent, it even enhances the privacy of the cross-chain transaction. Meanwhile, we also present the first concrete cross-chain virtual payment channel scheme, which only requires one of the blockchain systems supporting the Turing-complete scripting language. The corresponding detailed security analysis in the Universal Composability framework demonstrates that our proposal holds the Consensus on Open, Update, and Close. Finally, we implement and deploy our cross-chain virtual payment channel scheme on the Ethereum and Bitcoin test networks. The extensive experimental results show that our proposal dramatically improves the efficiency of cross-chain transactions, and the advantage becomes more pronounced as the number of transactions increases.

Capacity Region Bounds for Optical WDM Channels Based on First-Order Regular Perturbation

It is known that fiber nonlinearities induce crosstalk in a wavelength division multiplexed (WDM) system, which limits the capacity of such systems as the transmitted signal power is increased. A network user in a WDM system is an entity that operates around a given optical wavelength. Traditionally, the channel capacity of a WDM system has been analyzed under different assumptions for the transmitted signals of the other users, while treating the interference arising from these users as noise. In this paper, we instead take a multi-user information theoretic view and treat the optical WDM system impaired by cross-phase modulation and dispersion as an interference channel. We characterize an outer bound on the capacity region of simultaneously achievable rate pairs, assuming a simplified <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$K$</tex-math></inline-formula> -user perturbative channel model using genie-aided techniques. Furthermore, an achievable rate region is obtained by time-sharing between certain single-user strategies. It is shown that such time-sharing can achieve better rate tuples compared to treating nonlinear interference as noise. The achievable rates using the latter strategy are known to exhibit a maximum for an optimum launch power, beyond which a further increase of power leads to a reduction in achievable rates. For the single-polarization single-span system under consideration and a power 3.5 dB above the optimum launch power, treating nonlinear interference as noise results in a rate of 4.25 b/sym, while time-sharing gives a rate of 7.99 b/sym.

Efficient system for CPU metric visualization

There are multiple metrics associated with the smooth and efficient working of a computer system. Some of the crucial parts are like the CPU, memory usage and GPUs. For different Operating Systems, they have their own System Software for managing and analysing their sessions. Like Task Manager in Windows, Nmon in Linux and Activity Monitor in Mac. In addition to it, there are few applications software’s which perform similar tasks with slight modifications. In this paper, a web application is proposed that will fetch these performance metrics from the user's system and display them using dynamic charts. The proposed application is a system independent tool and can be useful for all operating system. The application also can be used to determine whether or not a game is compatible with the user's system based on the system requirements.

Prevalence, risk and severity of SARS-CoV-2 infections in psoriasis patients receiving conventional systemic, biologic or topical treatment during the COVID-19 pandemic: a cross-sectional cohort study (PsoCOVID)

BackgroundThe risk of SARS-CoV-2 infection does not appear to be increased for psoriasis patients using biologics compared to those on other treatments, but evidence is still limited.Objectives(1) to estimate the prevalence of SARS-CoV-2 infection in patients with psoriasis, (2) to compare SARS-CoV-2 infection rates for different psoriasis treatments groups (biologic vs. systemic conventional vs. topical therapy) corrected for confounders and (3) to describe patients with severe COVID-19 for all treatment groups.MethodsIn this cross-sectional cohort study all patients received a questionnaire to gather data on psoriasis treatment, SARS-CoV-2 infections and related risk factors. Simultaneously, they underwent a blood test to screen for antibodies to SARS-CoV-2 N-antigen. Prevalence of SARS-CoV-2 infections was calculated and logistic regression and Cox proportional-hazards models were performed to determine the association between treatment group and SARS-CoV-2 infection risk, corrected for confounders. Patients with severe COVID-19 disease were described and the mortality rate per treatment group was calculated for the target population.ResultsPatients were included between April 12 2021 and October 31 2021. Of 551 patients, 59 (10.7% (CI95% 8.3–13.6)) had experienced a SARS-CoV-2 infection, based on questionnaire data combined with serological data. In our study cohort, corrected for confounders, biologic or non-biologic systemic therapy users did not appear to have increased SARS-CoV-2 infection risk compared to patients using other treatment. Only 4 hospitalizations (0.7% (CI95% 0.2–1.0) were reported in our study population and no ICU admissions were reported. The rough mortality rate in the target cohort was 0.32% (CI95% 0.13–0.66) in all treatment groups.ConclusionsCorrected for risk-mitigating behavior and vaccination status, a higher SARS-CoV-2 incidence for biologics or non-biologics systemics compared to other treatments could not be proven. Severe cases were infrequent in all treatment groups. This finding further strengthens treatment recommendations that systemic therapies for patients with psoriasis do not require preventive cessation for reduction of SARS-CoV-2 infection risk.

Serum, saliva, and gingival tissue human β-defensin levels in relation to retinoic acid use.

Retinoic acid is an active derivative of vitamin A and regulates the differentiation, proliferation, and antimicrobial peptide expression profiles of human cells. The aim of the present study was to analyze the effect of systemic retinoic acid use on serum, saliva, and gingival tissue levels of human β-defensin (hBD)-1, hBD-2, and hBD-3. A total of 69 participants (34 systemic retinoic acid users and 35 healthy controls) were enrolled in this study. Plaque index, probing pocket depth, bleeding on probing (BOP), and clinical attachment loss were measured. Saliva and serum hBD-1, hBD-2, and hBD-3 levels were quantified by enzyme-linked immunosorbent assay. Gingival tissue hBD-1, hBD-2, and hBD-3 levels were determined by immunohistochemistry. A univariate general linear model was used in adjusted comparisons of hBD1, hBD-2, and hBD-3. P values of < 0.05 were considered statistically significant. Reduced salivary levels of hBD-2 (P = 0.042), but not hBD-1 or hBD-3, were detected in systemic retinoic acid users compared to non-user controls. There was a significant difference in the adjusted (for BOP%) salivary hBD-2 concentrations between retinoic acid and control groups (P = 0.031). No difference was observed in serum or tissue levels of hBD-1, hBD-2, or hBD-3 between the two study groups. Systemic retinoic acid use was associated with suppressed salivary hBD-2 level, which was independent of gingival inflammation.

Decoupling analysis of China's mining industrial development and water usage: Based on production-based and consumption-based perspectives

Mining is one of the most significant water users in the socioeconomic system. To safeguard water resources while ensuring mining safety and maintaining economic growth, it is vital to decouple water usage from mining industry expansion. Previous studies have mainly focused on direct water withdrawal in the power sector, whereas water usage, especially the embodied water footprint (WF) in the mining sector, has received less attention. This study employed the Tapio decoupling index and input‒output analysis to explore the relationship between the mining industrial development of four major mining sectors and their Production-based Water Usage (PWU) and Consumption-based Water Usage (CWU) in China from 2002 to 2015. We found that (1) During the study period, the total PWU, which presents an inverted U-shaped tendency increasing by 31.74%, was much larger than the CWU, decreasing by 18.6%, and their gap gradually widened. The “Mining and Washing of Coal” (MWC) and the “Mining and Processing of Metal Ores” (MPMO) were the largest consumers in the PWU and CWU, respectively. (2) The PWU of the whole mining sector presented a strong negative decoupling from 2002 to 2015. The “Mining and Processing of Nonmetal Ores” (MPNO) achieved strong decoupling, while MPMO and MWC presented strong negative decoupling and the “Extraction of petroleum and natural gas” (EPNG) displayed weak negative decoupling. (3) In terms of the CWU, except for EPNG, the other three sectors displayed recession decoupling, resulting in the whole mining sector presenting a recession decoupling state. Overall, our results could provide a scientific basis for the rational use of water resources in the mining sector.

Teorije in modeli v vedenjskih informacijskovarnostnih raziskavah

Behavioral information security is concerned with explaining the role of users in the information security system, drawing on various psychological, organizational, and criminological theories to explain and predict user behavior. Despite numerous systematic literature reviews on the field of information security, there is no comprehensive systematic review of the theories used in behavioral information security research. The purpose of this paper is to investigate which theories are most widely used in research, in which subject areas they are most used, which factors are most frequently included in research according to each set of theories, and which are most frequently statistically significant. Accordingly, we made two studies involving a systematic review of the literature over the past ten years. The findings suggest that the most used theories include the protection motivation theory and the theory of planned behavior. In these two theories, self-efficacy and perceived usefulness of the technology are factors, which are most often statistically significant in predicting self-protective behavior.

Compensation of Distributed Generations Outage Using Controlled Switched Capacitors

Researchers recently came up with innovative ways to generate enough electricity to meet the rising demand through establishing an electricity distribution system and enhancing power quality on the customer side. One of these innovative ways is the installation of distributed generation (DG). DG is widely used in modern networks due to its great benefits of improving the voltage profile and the system’s power quality. Additionally, DGs are ideally placed near the end user in distribution systems to improve the system’s performance while minimizing power losses and enhancing voltage profile in the grid. DG recently grew in importance, and its penetration increased in most distribution systems. Due to the spreading of DG in the power system, the dynamic performance of the system is affected. This paper studies the system’s performance and behavior under condition of DG outage from the system. The model of DGs in this study assumes two cases of the power provided to the network; the first case considered DG units injecting active power only to the grid (unity power factor). In the second case, DG injects both active and reactive power to the system. After that, outage of DG units is fixed by injecting a reactive power source using a capacitor with a controlled switch to compensate the outage of DGs from the distribution system and to reduce the outage’s negative effect on the network. The sizing of capacitors is optimized using a harmony search algorithm (HSA) in the same location of the DG units.

Enabling unmanned aerial vehicle to serve ground users in downlink NOMA system

The emergence of internet-of-things (IoT) devices in homes and industry, has resulted in the current and future generation of wireless communications facing unique challenges in spectral efficiency, energy efficiency, and massive connectivity issues. Non-orthogonal multiple access (NOMA) has been proposed as a viable solution to address these challenges as it offers low-latency, spectral efficiency, and massive connectivity capabilities, which are key requirements in upcoming next-generation networks. In addition, another technology that has emerged as a solution to spectral efficiency and coverage is an unmanned aerial vehicle (UAV). Therefore, the combination of UAVs with NOMA has great potential to minimize the challenges and maximize the benefits. Specifically, we investigate the outage performance of the NOMA-UAV network over Nakagami-m channel fading. To this end, we derive a closed-form outage performance metric. The formulated framework is validated using simulations to verify the effectiveness of the proposed solution.

Joint Power-Control and Antenna Selection in User-Centric Cell-Free Systems With Mixed Resolution ADC

In this paper, we propose a scheme for the joint optimization of the user transmit power and the antenna selection at the access points (AP)s of a user-centric cell-free massive multiple-input-multiple-output (UC CF-mMIMO) system. We derive an approximate expression for the achievable uplink rate of the users in a UC CF-mMIMO system in the presence of a mixed analog-to-digital converter (ADC) resolution profile at the APs. Using the derived approximation, we propose to maximize the uplink sum-rate of UC CF-mMIMO systems subject to energy constraints at the APs. An alternating-optimization solution is proposed using binary particle swarm optimization (BPSO) and successive convex approximation (SCA). We also propose a complete meta-heuristic-based solution that can be used as an alternative solution for applications where latency is the critical metric. Along with this, we used a genetic algorithm (GA)-based approach to compare the performance of the proposed algorithm. We study the impact of various system parameters on the performance of the system.

Collaboration in the Sky: A Distributed Framework for Task Offloading and Resource Allocation in Multi-Access Edge Computing

Recently, unmanned aerial vehicles (UAVs)-assisted multi-access edge computing (MEC) systems emerged as a promising solution for providing computation services to mobile users outside of terrestrial infrastructure coverage. As each UAV operates independently, however, it is challenging to meet the computation demands of the mobile users due to the limited computing capacity at the UAV’s MEC server as well as the UAV’s energy constraint. Therefore, collaboration among UAVs is needed. In this article, a collaborative multi-UAV-assisted MEC system integrated with an MEC-enabled terrestrial base station (BS) is proposed. Then, the problem of minimizing the total latency experienced by the mobile users in the proposed system is studied by optimizing the offloading decision as well as the allocation of communication and computing resources while satisfying the energy constraints of both mobile users and UAVs. The proposed problem is shown to be a nonconvex, mixed-integer nonlinear programming (MINLP) problem that is intractable. Therefore, the formulated problem is decomposed into three subproblems: 1) users tasks offloading decision problem; 2) communication resource allocation problem; and 3) UAV-assisted MEC decision problem. Then, the Lagrangian relaxation and alternating direction method of multipliers (ADMMs) methods are applied to solve the decomposed problems, alternatively. Simulation results show that the proposed approach reduces the average latency by up to 40.7% and 4.3% compared to the greedy and exhaustive search methods.

Analisis Teknik Entity-Relationship Diagram dalam Perancangan Database Sebuah Literature Review

There are many techniques used in database design. One of them is entity relationship diagram technique. ERD is one of the main diagrammatic representations of the conceptual data model that reflects the data requirements of users in a database system. ERD is also the first stage in database design. There are several things that must be considered in making an ERD for database design including, each database must have entities that are interconnected by relationships and each entity must have attributes consisting of a primary key as a characteristic of the entity and descriptive attributes. Many users have failed to create a database due to errors in the ERD creation. These errors can be conceptual errors, procedural errors, or technical errors. Therefore, this paper was made using the SLR method, namely by reviewing various kinds of references that discuss database design and then drawing conclusions, to make it easier for users to overcome problems that occur when making ERD and when implementing it.

More than health care

The Norwegian community health centres are one of the main providers of maternal and child health care services. They are often the primary, as well as a regular point of contact, for women during pregnancy and after childbirth. As such, they are a place where encounters between primary health care providers like public health nurses, midwives and immigrant women, are frequent. Midwives and public health nurses play an important role as state employees in the distribution of universal health provisions at the local level. This is especially important in meeting the diverse needs of service users in a universal health care system. This study investigates the implications of cultural diversity for health care practice in a universal system. It employs a qualitative approach, using data from nine semi-structured interviews with midwives and public health nurses across three Norwegian municipalities. It analyses their experiences in working with immigrant women during pregnancy, and after childbirth, through thematic analysis. The findings illustrate the practitioners’ different approaches to meeting with culturally diverse patients, the challenges they face in their work, and how they overcome them. The discussions address the practice of cross-cultural health care in the absence of national guidelines or formal training using street-level bureaucracy as an analytical concept. This article contributes to knowledge on the practice of cross-cultural health care at Norwegian community health centres in the absence of a culturally cognizant health policy. On a broader scale, this study illustrates the implications of diversity for policy and practice in a universal welfare state.