A Task Allocation Algorithm with Weighted Average Velocity Based on Online Active Period

In some complex scientific calculation, the resources of the calculation are very large. To a certain extent, the improvement of the computer level has met the needs of many computing, but a lot of more complex calculation cannot still be effectively resolved. Volunteer computing is a computational method that divides the complexity of computing tasks into simple subtasks, and collects the results of volunteer computing resources to solve the subtasks. In this calculation process, the task assignment module is an extremely important part of the whole computing platform. Many of the existing task allocation algorithms (TAA) are used to group by the similar conditions of the volunteer computer. TAA used in this work grouped by the computers with similar online active period, and the computation efficiency is improved by using the weighted average velocity as a parameter. The experimental results showed that TAA with the weighted average velocity based on online active period can effectively improve the performance of the volunteer computing platform. Keywords: Volunteer computing; Task allocation algorithm; Weighted average velocity; Online active perio

Prevalence and risk factors of suicide in a rural area of Shandong province in mainland China: a case control study

Objective: Suicide is a major public health problem in China, particularly in rural areas. This study aimed to examine the rate  and the risk factors for suicide in a rural area of China. Methods: The mortality data of two counties in Shandong Province from January 1st, 2004 to December 31st 2005 were used. Death information was collected via face-to-face interview with informant(s). Psychological autopsy was conducted on 137 completed suicides and 137 matched controls died from other illnesses. Chi-square/Fisher exact and multiple logistic regression were used for bivariate analyses and predictor analyses, respectively. Results: The suicide rate was 20.90 per 100,000 persons per year with almost equal rates of males and females. Among those with the age over 40 years old, the suicide rate in males was significantly higher than that in females. The peak of suicide fell in the age group of 70-79 years for males and the age group of ≥ 80 years for females. The most commonly used method for suicide was pesticide ingestion (76.7%). Poor interpersonal relationship (OR=12.79), childhood adversities (OR=7.26), a history of mental illness (OR=5.95), adverse life event(s) within 1 year prior to death (OR=3.19), and unstable extravert personality traits (OR=6.12) were independent risk factors for suicide. Male gender positively interacted with majority of these risk factors, especially with a history of mental illness (OR=17.89). Advanced age positively interacted with all independent risk factors, with a history of mental illness having the largest OR of 1.51 as every 10 year of age advancement. In bivariate analyses, a history of previous suicide attempt (OR=13.06), a family history of suicide (OR=7.08), and unstable introvert personality trait (OR=1.83) were also associated with increased risk for suicide; and stable extravert personality trait (OR=0.21) was associated with decreased risk for suicide. Conclusions: In this rural population of mainland China, the risk for suicide was almost equal in both males and females with the elderly having the highest risk. The positive interactions of advanced age and male gender with independent risk factors suggest that suicide prevention strategies targeting specific groups with different risk factors are essential.Objective: Suicide is a major public health problem in China, particularly in rural areas. This study aimed to examine the rate  and the risk factors for suicide in a rural area of China. Methods: The mortality data of two counties in Shandong Province from January 1st, 2004 to December 31st 2005 were used. Death information was collected via face-to-face interview with informant(s). Psychological autopsy was conducted on 137 completed suicides and 137 matched controls died from other illnesses. Chi-square/Fisher exact and multiple logistic regression were used for bivariate analyses and predictor analyses, respectively. Results: The suicide rate was 20.90 per 100,000 persons per year with almost equal rates of males and females. Among those with the age over 40 years old, the suicide rate in males was significantly higher than that in females. The peak of suicide fell in the age group of 70-79 years for males and the age group of ≥ 80 years for females. The most commonly used method for suicide was pesticide ingestion (76.7%). Poor interpersonal relationship (OR=12.79), childhood adversities (OR=7.26), a history of mental illness (OR=5.95), adverse life event(s) within 1 year prior to death (OR=3.19), and unstable extravert personality traits (OR=6.12) were independent risk factors for suicide. Male gender positively interacted with majority of these risk factors, especially with a history of mental illness (OR=17.89). Advanced age positively interacted with all independent risk factors, with a history of mental illness having the largest OR of 1.51 as every 10 year of age advancement. In bivariate analyses, a history of previous suicide attempt (OR=13.06), a family history of suicide (OR=7.08), and unstable introvert personality trait (OR=1.83) were also associated with increased risk for suicide; and stable extravert personality trait (OR=0.21) was associated with decreased risk for suicide. Conclusions: In this rural population of mainland China, the risk for suicide was almost equal in both males and females with the elderly having the highest risk. The positive interactions of advanced age and male gender with independent risk factors suggest that suicide prevention strategies targeting specific groups with different risk factors are essential

Lower Bounds of Concurrence for Tripartite Quantum Systems

We derive an analytical lower bound for the concurrence of tripartite quantum mixed states. A functional relation is established relating concurrence and the generalized partial transpositions.Comment: 10 page

A Low-Profile Frequency Reconfigurable Grid-Slotted Patch Antenna

This paper presents a novel low-profile high gain frequency reconfigurable patch antenna with unidirectional radiation pattern by using a grid-slotted patch with tunable varactors loading. The antenna consists of two stacked substrates and three metal layers. A grid-slotted patch with two tunable varactors is placed on the top layer, a microstrip line is placed in the middle of two substrates, and the ground plane is on the bottom layer. A single dc voltage applied on two varactors is used to control the working frequencies of the proposed antenna. By altering the bias voltage, the working frequency of the proposed antenna can be continuously changed within a wide range from 2.45 to 3.55 GHz. The antenna maintains broadside radiation and stable radiation pattern in all the operating modes. The measured antenna gain of the proposed antenna rises from 4.25 to 8.49 dBi with the working frequency increases from 2.45 to 3.55 GHz. Compared to other frequency-reconfigurable antennas available in the literature, the proposed antenna has advantages of a wide frequency tuning range over a bandwidth of 1.45:1, high frequency selectivity, low profile (0.016 free-space wavelength at 2.45 GHz), high gain, stable unidirectional pattern, simple structure, and low cost. These advantages make it a promising candidate for cognitive radio and future wireless communication system

Separability of rank two quantum states on multiple quantum spaces

Explicit sufficient and necessary conditions for separability of $N$-dimensional rank two multiparty quantum mixed states are presented. A nonseparability inequality is also given, for the case where one of the eigenvectors corresponding to nonzero eigenvalues of the density matrix is maximally entangled.Comment: 10 pages, Late

Optimal scheduling of integrated energy systems with exergy and demand responsiveness

To fairly use demand response to regulate customer load , support the economic and environmental protection, and assess the quantity and quality of the synergistic growth of the integrated energy system, a multi-objective optimum scheduling model and a solution method considering exergy efficiency and demand response are presented. To begin with, a mathematical model of each energy gadget is created. The electricity–gas load demand response model is then built using the price elasticity matrix, while the cooling load demand response model is built taking into account the user’s comfort temperature. On this basis, a multi-objective optimal dispatching model is developed with the optimization goals of minimizing system operation costs, reducing carbon emissions, and increasing exergy efficiency. Finally, the model is solved using NSGA-II to produce the Pareto optimal frontier solution set in various situations, and the VIKOR decision procedure is utilized to identify the complete best dispatching solution. The simulation results suggest that the proposed model can match the system’s scheduling needs in terms of numerous objectives such as economy, environmental protection, and exergy efficiency while also assuring user’s comfort

A Novel Ultrawideband Transmitarray Design Using Tightly Coupled Dipole Elements

One of the key challenges in transmitarray (TA) designs is its narrow bandwidth. To overcome this limitation, this paper proposes a novel design of ultrawideband TA antenna based on tightly coupled dipole arrays (TCDAs). The array consists of 20 × 10 unit cells, and each unit cell is composed of a pair of short dipoles connected with a section of meandered transmission line. The size of each unit cell is 20 mm × 10 mm, which is about 0.2λ × 0.1λ, where λ is the wavelength in free space at the lowest working frequency of the TA. By utilizing the strong coupling between adjacent units of the TA, the bandwidth of the TA is improved significantly. To verify the design concept, one prototype of the proposed TA is fabricated and measured. The prototype demonstrates good performance over a bandwidth of 104%, i.e., from 3.0 to 9.5 GHz, which is significantly wider than that of other TAs reported in the literature. Within the working band of the TA antenna, the radiation pattern is stable and no distortion or splitting of the main beam of the antenna is observed. This is the first time that the TA based on TCDA is reported