Implementation and application of PyNE sub-voxel R2S for shutdown dose rate analysis

PyNE R2S is a mesh-based R2S implementation with the capability of performing shutdown dose rate(SDR)analysis directly on CAD geometry with Cartesian or tetrahedral meshes.It supports advanced variance reduction for fusion energy systems.However,the assumption of homogenized materials of PyNE R2S with a Cartesian mesh throughout a mesh voxel introduces an approximation in the case where a voxel covers multiple non-void cells.This work implements a sub-voxel method to add fldelity to PyNE R2S with a Cartesian mesh during the process of activation and photon source sampling by performing independent inventory calculations for each cell within a mesh voxel and using the results of those independent calculations to sample the photon source more precisely.PyNE sub-voxel R2S has been verifled with the Frascati Neutron Generator(FNG)-ITER and ITER computational shutdown dose rate benchmark problems.The results for sub-voxel R2S show satisfactory agreement with the experimental values or reference results.PyNE sub-voxel R2S has been applied to the shutdown dose rate calculation of the Chinese Fusion Engineering Testing Reactor(CFETR).In conclusion,sub-voxel R2S is a reliable tool for SDR calculation and obtains more accurate results with the same voxel size than voxel R2S.

Frequency of Monthly Ejaculation at Sexual Intercourse, DNA Fragmentation Index and Fertilization Rate among Sperm Donors and Fertility-Challenged Men in Sub-Saharan Africa: Paper 2

Introduction: Heterogenous sexual intercourse often produces a powerful orgasm that stimulates the pituitary function. Studies have suggested ejaculation frequency based on age. Materials and Methods: Semi-structured questionnaires were used to collect information from subjects. Semen samples were collected from sperm donors and sub-fertile men who presented for infertility challenges. Processing and analysis of semen samples were done according to World Health Organization (WHO) guidelines. Sperm deoxyribonucleic acid (DNA) fragmentation was evaluated using the Halosperm kit. Results: Among sperm donors, those aged χ2 = 0.09, P-value = 0.81, OR = 3.2, 95% CI: 0.23, 45.19) while among sub-fertile men those aged ≥40 years were approximately 2.3 times more likely to have very low frequency of MESI compared to aged χ2 = 2.11, P-value = 0.51, OR = 2.27, 95% CI: 0.74, 9.92). The frequency of all categories of MESI was highest among sub-fertile men aged χ2 = 0.03, P-value = 0.57, OR = 2.42, 95% CI: 0.41, 14.46). Sub-fertile men aged ≥40 with diastolic hypertension (≥90 mmHg) were approximately 6 times more likely to have a low (6 - 10) frequency of MESI compared to those aged χ2 = 1.97, P-value = 0.16, OR = 6.22, 95% CI: 0.69, 55.77). Overall mean fertilization rate was significantly higher (t-test = 2.44, P-value = 0.01) among sub-fertile men aged Conclusion: Cigarette smoking, more than alcohol consumption, appears to be a major factor that significantly affects the frequency of MESI among sub-fertile men in all age groups. Frequency of MESI negatively but insignificantly correlated with systolic blood pressure.

Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas Woodlands

Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response curves at ambient and elevated levels of CO2 and temperature were measured for D. texana. The Anet (photosynthetic rate) increased significantly as both light level and CO2 levels increased but not temperature. The Amax (maximum photosynthetic rate) of D. texana in full sun at elevated levels of CO2 was increased for all treatments. Stomatal conductance increased with levels of CO2 but only if the interaction was removed from the model. Intercellular levels of CO2 increased with both temperature and CO2 treatments as did water use efficiency (WUE). Furthermore, light saturation (Lsat) increased with CO2 treatments and light compensation (Lcp) increased with temperature. The dark respiration (Rd) increased with both temperature and CO2 treatments. Markov population models suggested D. texana populations would remain ecologically similar in the future. However, sub-canopy light levels and herbivory should be considered when examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herbivory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to be a problem for D. texana juveniles which would allow them to reach the canopy without need of a high light gap and are not prevented by herbivory. Thus, Juniperus/Quercus woodlands will change in the future to woodlands with D. texana a more common species.

Effects of elevated CO_2 on net photosynthetic rate of trees in Changbai Mountain

Net photosynthetic rates (NPRs) of four species seedlings, Pinus koraiensis, Ptrius Syvestriformis,Fraxinus mandshuthe and Phellodendron amurense, were measured at different CO2 concentrations and time respectively in Changbai Mountain during the growing season in 1999. The seedlings were cultivated in open-top chambers (OTCs), located outdoors and exposed to natural sunlight. The experimental objects were divided into four groups by tree species. CO2 concentrations in chambers were kept at 500 μL-L-1 and 700 μL-L-1 and contrast chamber and contrast field were set. The results showed that the effects of elevated CO2 on NPR of the trees strongly depended on tree species and time. NPRs of Pin us koreaipsis and Pinus syvestriformis seedfings increased with the rising of CO2 concentration, while that of Phellodron amurense and haus mandshurica increased at some time and decreased at another time.

Physiological Performances of Temperate Vegetables with Response to Chronic and Acute Heat Stress

In face of climate change catastrophes, understanding the thermal limits and optimal physiological thermal window food crop is of particular urgency. This research aims to evaluate: 1) how physiological performances of plant will change with increasing chronic and acute heat stress;2) if the examined parameters form a hierarchy in terms of thermal tolerance;and 3) the optimal thermal window and critical temperatures of the examined plants with response to chronic and acute heat stress. Six temperate vegetables were subjected to chronic and acute heat stress and a suite of physiological parameters were evaluated. Dose responses were observed in shoot fresh weight, photosynthetic gas exchange, photosynthetic oxygen evolution, electron transfer rate, photo- and non-photochemical quenching with significant drop in performance as early as 28°C for selected species. Conversely, ratio of variable to maximum fluorescence (Fv/Fm) was not affected by heat stress until 46°C in chronic heat stress. Examining the temperature at which a measured parameter’s performance dropped by 50% compared to control (LT50), a distinct hierarchy of the indices was observed for Canasta, recombinant inbred line 141, Lactuca serriola and Lactuca sativa (L. “Salinas”): shoot fresh weight, representing the highest integrated level of photosynthesis was the most sensitive to thermal stress (28°C - 30°C), followed by oxygen evolution (35°C - 45°C) while non-photochemical and photochemical quenching which is subcellular function of stress alleviation had a much higher capacity failure temperature (47°C - 60°C). It is expected that Fv/Fm ratio, a measurement of sub-cellular structural integrity, will approach that of non-photochemical and photochemical quenching, if not exceeding it. By examining the photosynthetic parameters via their hierarchy of biological organization, it can be inferred that plants like Arugula and recombinant inbred line 192 are already operating near their thermal limit and have less energetic investment into heat stress mediation whereas L. serriola prioritizes thermal tolerance at the expense of photosynthesis efficiency.

Performance Analysis of Sub-Rating for Handoff Calls in HCN

Hierarchical Cellular Networks (HCN) offer more efficient channel utilization and better quality of service (QoS) under the high tele-traffic condition compared to the single-tier system. One of the important measures of QoS in HCN as in any single-tier system is the handoff dropping rate. Although the existing approaches such as guard channel and queuing can reduce forced termination probability, they also result in higher new call blocking probability. The channel sub-rating strategy has found to be an effective technique to reduce the handoff force termination probability while preserving the new call blocking probability in a single-tier system. In this paper, we propose a new call admission control scheme for HCN based on the channel sub-rating. Analytic models based on 1-D Markov process in microcell and 2-D Markov process in macrocell are developed. Experimental results show that our scheme achieves lower blocking and forced termination probabilities compared to the traditional guard channel scheme. The effect of channel sub-rating on the voice quality degradation is also studied. Results demonstrate that we can establish a good balance between the forced termination probability and the voice quality degradation by varying the number of sub-ratable full-rate channels.

Influence of N2 flow rate on structure and properties of TiBCN films prepared by multi-cathodic arc ion plating and studied with ion beam scattering spectroscopy

TiBCN films were deposited on Si(100) and cemented carbide substrates by using multi-cathodic arc ion plating in C_2H_2 and N_2atmosp^here. Their structure and mechanical properties were studied systematically under different N_2 flow rates. The results showed that the Ti BCN films were adhered well to the substrates. Rutherford backscattering sp^ectroscopy was employed to determine the relative concentration of Ti, B, C and N in the films.The chemical bonding states of the films were explored by X-ray photoelectron sp^ectroscopy, revealing the presence of bonds of Ti N, Ti(C,N), BN, pure B, sp^2C–C and sp^3C–C, which changed with the N_2 flow rate. Ti BCN films contain nanocrystals of Ti N/Ti CN and Ti B_2/Ti(B,C)embedded in an amorphous matrix consisting of amorphous BN and carbon at N_2 flow rate of up to 250 sccm.

Spatial Distribution of CO2 Concentration over South America during ENSO Episodes by Using GOSAT Data

Carbon dioxide (CO2) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is the Earth’s strongest climate fluctuation on inter-annual time scales and has global impacts. However, to date, there is no research on how ENSO affects the spatial distribution of CO2 concentration. In this study, we used spatial CO2 data from the ENVIronmentSATellite (ENVISAT) and the Greenhouse Gases Observing Satellite (GOSAT), the long duration monthly mean atmospheric CO2 from Mauna Loa Observatory, Multivariate ENSO Index (MEI) from Earth System Research Laboratory to analyze the way that ENSO affects spatial distribution of CO2 concentration in South America, which is affected by ENSO seriously. Our research revealed that monthly CO2 growth rate has a moderate, positive correlation relationship with MEI. We used geostatistics to predict and simulate the spatial distribution of CO2 and found that in south of 12°S, CO2 concentration of ENSO warm episode is lower than the one of ENSO cold and neutral episodes. ENSO impacts CO2 spatial distribution mainly in November, December, January and February;moderate-high concentration zone of ENSO warm episode more concentrates in the northern part of South America.

Digestive Rate of Dongtian F_1 Red Dear in Weaning Period and Growth Period

in this paper, 4N-HCLAIA method was adopted to conduct digestive tests in young female and male Dongtian F1 red deer (Cervus elaphus) of rearing seperatefy in growth period and mixed raising in weaning period in Harbin Specialty Research Institute. Results indicated that digestive rate of crude protein and crude fiber were 95.35% and 73.68% respectively when rational protein content was 26.8% in growth period. Digestive rate was not significantly different between female and male(P>0.05)i During weaning period, When rational crude protein content is 22.06%, digestive rate of crude protein and crude fiber were 93.05% and 63.96%, respectively. The tests suggest that higher rational protein can be effective in accelerating groWth of young Dongtian F1 red deer during growth period and weaning period(before 10 months old).

Ni3Al-Ni3V合金的室温摩擦磨损性能

为研究Ni3Al-Ni3V合金的室温磨损机理,采用固溶时效和渗碳工艺制备了不同微观组织的Ni3Al-Ni3V合金,通过往复式磨损实验机测试了其室温磨损性能。实验结果发现,固溶Ni3Al-Ni3V合金由软的Ni3Al相和硬的Ni3Al + Ni3V复合相组成;渗碳Ni3Al-Ni3V合金表面生成了厚度约4 μm的碳化物层和约6 μm的富Ni相过渡层,组织致密,与基体合金结合良好,具有较高硬度和弹性模量的碳化物层提高了合金的摩擦磨损性能。Ni3Al相对环境中水汽敏感,磨损过程中易与水汽反应产生环境脆性,导致Ni3Al-Ni3V合金发生了磨损环境脆性,Al的临界含量为5.53 at.%。随着载荷和滑动速度的增加,固溶Ni3Al-Ni3V合金的磨损机制由磨粒磨损和环境脆性转变为粘着磨损,渗碳Ni3Al-Ni3V合金的碳化物层和富Ni相过渡层逐渐被磨掉后,也发生了环境脆性。

低信噪比下无线声传感网络采样率偏移估计方法

现有的采样率偏移(Sampling Rate Offset,SRO)估计算法在低信噪比条件下性能严重下降.为了解决这个问题,本文提出一种基于子带二次互相关函数的频率滑动窗二次互相关(Frequency Sliding Double-Cross Correlation Processing,FS-DXCP)算法.该方法使用频域滑动窗口构建无线节点观测信号间的子带二次互相关函数矩阵,进而利用奇异值分解来自适应地消除低信噪比频段对二次互相关函数估计的影响,最后搜寻二次互相关函数的极大值点获得SRO的估计.计算机仿真实验表明:在信噪比为-5 dB时,所提方法的采样率频偏平均估计误差为4.21百万分率(part per million,ppm),这比现有的DXCP-PHAT算法的估计误差降低了约8.17 ppm.所提算法有效提升了低信噪比条件下采样率频偏的估计精度.

危险化学品企业设备评估分级系统的构建

随着化工技术的发展进步,各大危险化学品企业趋于集约化,在日常监管和检查中发现,一些危险化学品企业存在管理不系统、不全面,无法依据企业现状划分企业等级,不利于危险化学品企业的监督管理,这些都成为制约企业安全发展的重要因素。通过对危险化学品企业现有设备的完整性评估,建立以设备完整性为基础的分级系统迫在眉睫。该系统的建立依托相应领域专家经验和层次分析的方法,客观公正地给出危险化学品企业设备管理得分后,辅助企业分析出相对薄弱环节,通过分值拟合以及斜率变化,将危险化学品企业划分成4个类别,针对不同类别提出有针对性的监控调整措施及建议,为企业的安全生产提供了技术支持。

基于码率-准确率优化的图像特征压缩

在智慧城市、智慧巡检、智慧交通等场景中,摄像头等终端设备会产生大量的图像视频数据,并在云端由智能处理算法进行图形分析。然而传统的源端图像视频压缩传输,后端特征提取与分析识别的处理框架易造成视觉特征受损,影响分析识别精度。因此,源端提取图像特征,压缩后传输到后端的处理框架成为新的热点。文中提出了一种基于码率-准确率优化的图像特征压缩方法。首先,提取图像特征,分析划分特征图重要性的标准,将特征图分为重要性和非重要性特征两部分,并分别进行量化。在此基础上,建立码率-准确率的模型,在给定码率条件下,求解最优的准确率,确定相应的量化参数。以图像分类作为智能分析任务开展了实验。实验结果表明,所提出方法可以优化选择不同区域的量化参数,获得更好的编码性能。在低码率的条件下,相较JPEG算法准确率提高9.73%。

心率变异性生物反馈训练对基层指挥员亚健康的影响

目的探讨心率变异性生物反馈(heart ratevariability biofeedback,HRVB)训练对基层指挥员亚健康及心率变异性(heartratevariability,HRV)的影响,为提高基层指挥员心理健康水平及心理生理能力提供依据。方法采用两因素混合实验设计(组别×训练次数),选取47名陆军基层指挥员,完全随机分为对照组22名(不接受HRVB训练)和实验组25名(接受HRVB训练)。采用亚健康评定量表和HRV评估实验前后指挥员亚健康心理和生理状况。结果HRVB训练后实验组亚健康状况较训练前明显改善(P<0.05);对照组HRV正常窦性心搏间期的标准差(standard deviation of all normal to normal intervals,SDNN)、极低频(verylow frequency,VLF)、总功率谱密度(total power,TP)呈下降趋势,且差异均有统计学意义(P均<0.05),而实验组保持相对稳定的状态,差异无统计学意义(P>0.05);实验组在训练3周后,HRV SDNN、全程相邻间期之差的均方根(root mean square of the successive normal to normal inter-valsdifference,rMSSD)、VLF、TP显著高于对照组(P均<0.05)。结论HRVB训练能有效改善基层指挥员亚健康水平及心理生理能力。

面向带通信号的随机解调模拟信息转换器设计

模拟信息转换器作为压缩感知理论的实际应用,能够在信号数字化的同时实现压缩采样,显著降低了系统功耗及数据处理负担,但在通信领域,高频带通信号的奈奎斯特率通常极高,这要求模拟信息转换器系统具备极高的采样频率,从而增加了设计复杂度。针对此挑战,提出了一种基于带通Sigma-Delta调制器的随机解调模拟信息转化器架构,以低速伪随机序列对带通信号进行解调处理,有效避免了高速伪随机信号混频模块可能引入的高功耗及电路设计误差等问题。此架构不仅将模拟信息转换器的应用范围从基带信号拓展至带通信号,还成功解决了伪随机信号转换速率受带通信号最高频率研制的技术难题。

亚共振双质体振动筛的研制与应用

针对振动筛故障率高、作业率底的问题,研制了亚共振双质体振动筛,该设备具有亚共振双质体技术、大型化、通用化、低维护量、智能化等性能特点,使用后比原振动筛作业率提高了8.3%,故障率、维护成本、能耗分别降低了5.2%、54.3%、75%,是一种安全可靠、维护方便、高效节能的振动筛分设备。

挖金湾煤业瓦斯治理技术应用研究

针对挖金湾煤业井下通风风量紧张,瓦斯涌出量急剧提升的现象,采用分源动态预测的方法对挖金湾煤业井下瓦斯涌出量进行了预测分析,通过对瓦斯压力、含量以及通风阻力等指标的测定,了解井下瓦斯状况,找出工作面瓦斯主要来源,并对井下瓦斯涌出量进行预测分析。通过制定瓦斯抽放及井下通风技术方案,提升了瓦斯抽采时间与浓度,提高瓦斯抽采率为73%,保证工作面回风流瓦斯浓度在0.4%以下,回采面上隅角与高位孔处浓度保持在4%~12%,符合煤矿井下安全高效生产要求。

一种半速率蜂窝移动通信信道指配策略

本文提出了一种新的蜂窝移动通信系统信道指配策略———基于紧凑模式的半速率信道借用指配策略(SRCPCB) .这种策略将半速率信道的思想引入到新近提出的CPCB策略中 ,以短时间降低部分呼叫的话音质量为代价 ,来降低系统的呼叫阻塞 .通过各种业务模型的仿真 ,获得了系统的初始呼叫阻塞率、强制中断率和话音质量下降率等性能指标 .结果表明 :SRCPCB的系统综合性能优于FCA、DCA、BCO、BDCL、CPDCA和CPCB等策略 .这对于缓解系统频谱资源紧缺、改善系统性能等具有十分重要的意义 .

新型厌氧反应器处理高浓度有机废水小试研究

采用新型厌氧反应器处理模拟高浓度有机废水,在中温条件下进行了为期150 d的试验,研究了新型厌氧反应器的启动过程以及对模拟高浓度有机废水的处理效果。结果表明,进水COD达到6 g.L-1,水力停留时间为11.1 h时,新型厌氧反应器的COD容积负荷达到12.96 kg.m-.3d-1,COD去除率为81%。

医学生自测亚健康状态及其影响因素

目的了解医学生自测亚健康状态及其主要影响因素。方法采取随机分层整群抽样方法,选择878名医学生应用自测健康评定量表(SRHMSV1.0)进行亚健康状态的调查,并对其性别、年级、专业、每天学习总时间、每天上网时间及每月生活费等主要影响因素进行分析。结果医学生总体健康好的比例为21.2%,总体亚健康发生率为54.9%,其中生理亚健康发生率为49.3%,心理亚健康发生率为28.6%,社会亚健康发生率为39.2%。女生生理、心理、社会亚健康发生率显著高于男生。每天上网时间不同等级的医学生总体亚健康发生率存在统计学意义(χ2=15.544,P=0.001)。不同年级、专业及每天上网时间的医学生总体健康状况构成存在统计学意义(P=0.000,P=0.005,P=0.000)。不同年级、专业医学生总体健康差及亚健康的比例存在统计学意义(P=0.000,P=0.005),以大二年级学生和临床医学专业学生所占比例最高。结论亚健康状态在医学生中已经普遍存在,性别、年级、专业及每天上网时间是影响医学生身心健康的主要因素,应有针对性地进行干预。