A New Result on Regular Designs under Baseline Parameterization

The study on designs for the baseline parameterization has aroused attention in recent years. This paper focuses on two-level regular designs for the baseline parameterization. A general result on the relationship between K-aberration and word length pattern is developed.

基于Baseline模型的刮板输送机健康评估

对刮板输送机进行可靠健康评估是保证工作面高效开采的关键。针对某煤矿综采工作面刮板输送机提出一种基于Baseline模型的健康评估方法。该方法采用长短时记忆(LSTM)深度神经网络建立运行参数的Baseline模型,预测正常的数值和故障发生上、下限阈值。在此基础上建立了真实值与预测值的6种偏差计算方法和设备健康评估机制。最后融合机头电机、机尾电机、机头减速器和机尾减速器的评估结果,完成刮板输送机运行健康综合评估。

Effect of non-uniform swelling on coal multiphysics during gas injection: The triangle approach

In current dual porosity/permeability models,there exists a fundamental assumption that the adsorption-induced swelling is distributed uniformly within the representative elementary volume (REV),irrespective of its internal structures and transient processes.However,both internal structures and transient processes can lead to the non-uniform swelling.In this study,we hypothesize that the non-uniform swelling is responsible for why coal permeability in experimental measurements is not only controlled by the effective stress but also is affected by the adsorption-induced swelling.We propose a concept of the swelling triangle composed of swelling paths to characterize the evolution of the non-uniform swelling and serve as a core link in coupled multiphysics.A swelling path is determined by a dimensionless volumetric ratio and a dimensionless swelling ratio.Different swelling paths have the same start and end point,and each swelling path represents a unique swelling case.The swelling path as the diagonal of the triangle represents the case of the uniform swelling while that as the two perpendicular boundaries represents the case of the localized swelling.The paths of all intermediate cases populate inside the triangle.The corresponding relations between the swelling path and the response of coal multiphysics are established by a non-uniform swelling coefficient.We define this method as the triangle approach and corresponding models as swelling path-based ones.The proposed concept and models are verified against a long-term experimental measurement of permeability and strains under constant effective stress.Our results demonstrate that during gas injection,coal multiphysics responses have a close dependence on the swelling path,and that in both future experiments and field predictions,this dependence must be considered.

Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conductivity.The novelty of this paper is the analysis of pressure performances caused by the fracture dynamics and polymer rheology,as well as an analysis method that derives formation and fracture parameters based on the pressure and its derivative curves.

An improved non-uniform fast Fourier transform method for radio imaging of coronal mass ejections

Radioheliographs can obtain solar images at high temporal and spatial resolution,with a high dynamic range.These are among the most important instruments for studying solar radio bursts,understanding solar eruption events,and conducting space weather forecasting.This study aims to explore the effective use of radioheliographs for solar observations,specifically for imaging coronal mass ejections(CME),to track their evolution and provide space weather warnings.We have developed an imaging simulation program based on the principle of aperture synthesis imaging,covering the entire data processing flow from antenna configuration to dirty map generation.For grid processing,we propose an improved non-uniform fast Fourier transform(NUFFT)method to provide superior image quality.Using simulated imaging of radio coronal mass ejections,we provide practical recommendations for the performance of radioheliographs.This study provides important support for the validation and calibration of radioheliograph data processing,and is expected to profoundly enhance our understanding of solar activities.

Er:YAG激光联合Ionosit-Baseliner复合体垫底材料在磨牙深龋中微渗漏的研究

目的:评估Er:YAG激光处理联合Ionosit-Baseliner光固化复合体垫底材料在深龋治疗中的微渗漏情况。方法:本实验将40颗离体磨牙随机分为四组,A组高速涡轮手机备洞后光固化氢氧化钙垫底,B组高速涡轮手机备洞联合Ionosit-Baseliner光固化复合体垫底材料,C组Er:YAG激光处理窝洞后光固化氢氧化钙垫底,D组Er:YAG激光处理窝洞后联合Ionosit-Baseliner光固化复合体垫底材料。A组为对照组,B、C、D组为实验组,通过对比高速涡轮手机备洞和Er:YAG激光备洞后是否联合使用Ionosit-Baseliner光固化复合体垫底材料的离体牙深龋模型的构建,观察树脂充填后微渗漏的情况,从而分析Er:YAG激光联合Ionosit-Baseliner光固化复合体垫底材料是否能提高窝洞充填的临床修复效果。结果:Er:YAG激光联合Ionosit-Baseliner光固化复合体垫底材料处理的离体牙的微渗漏程度与高速涡轮手机备洞后光固化氢氧化钙垫底的离体牙相比,微渗漏的深度明显不同,差异具有统计学意义(P<0.05);高速涡轮手机和Er:YAG激光处理离体牙后分别结合不同的垫底材料充填,其微渗漏的深度差异均无统计学意义(P>0.05);高速涡轮手机和Er:YAG激光处理离体牙后结合同一种垫底材料充填其微渗漏的深度亦均无统计学差异(P>0.05)。结论:Er:YAG激光处理牙体组织后联合Ionosit-Baseliner光固化复合体垫底材料充填能够有效减少深龋窝洞充填术后微渗漏的发生。

Ionosit-Baseliner在深龋盖髓中的应用

目的观察Ionosit-Baseliner(爱诺赛光固化复合体)用于深龋患牙盖髓术的临床疗效。方法将18～72岁152例患者的175颗深龋患牙,分为两组,治疗组以Ionosit-Baseliner间接盖髓,对照组以氢氧化钙间接盖髓。6个月、1年后分别复查并进行临床评价,观察两组盖髓术后的临床症状、牙髓活力、X线摄片情况。结果 6个月及1年后复查,两组盖髓作用的差别均无统计学意义(P>0.05)。结论 Ionosit-Baseliner可作为间接盖髓剂应用于临床深龋治疗,并且疗效很好,值得推广。

基于MAX+plusII 10.0 Baseline的数字电路设计

讨论 MAX+plus II10 .0 Baseline的功能和特点 ,提出以 VHDL 设计语言为手段、以 MAX+plus II10 .0Baseline为平台的数字电路的设计方法。

Baseline——一种容忍与检测DoS/DDoS攻击的被动方法(英文)

提出一种检测DoS/DDoS攻击(拒绝服务攻击/分布式拒绝服务攻击)的“Baseline”服务体系结构,并实现了其中关键的“Shepherd”检测算法。该体系结构通过把服务及其质量是否受到影响的判断指标交由具体的通信进程来定义而具有较强的适应性,可以与各种现有入侵检测系统很好地结合且不给宿主系统增加过多的开销。同时相比其他DoS/DDoS检测方式,Baseline服务无须对Internet路由基础设施作出更改来提供支持,是一种十分可行的DoS/DDoS检测方案。在理想情况下,Baseline服务可以做到对DoSDDoS入侵零误报。

基于Baseline SVD主动学习算法的推荐系统

推荐系统是一种解决信息过载的新型技术,为了解决推荐系统中新用户带来的冷启动问题,提出一种基于主动学习的推荐系统。主动学习方法能有效减少需要标记的样本数量,快速建立模型,在此选择将主动学习方法和Baseline SVD推荐算法结合起来,通过记录模型训练得到的预估评价的改变程度,认为改变最大的样例即是最具有信息量的样例,供新用户标记,并重新训练模型。通过与其他选择策略进行实验比较,证实了该方法确实有效解决了新用户带来的冷启动问题。

Baseline JPEG压缩器在Xilinx FPGA上的设计与实现

由于近年来胶囊内窥镜需求的发展,以及FPGA在小型化和低功耗的技术进步,在内窥镜系统中应用FPGA为核心的解决方案已经成为可能。在目前的FPGA数字胶囊系统,以及未来用于胶囊窥镜的专用集成电路中,图像数据压缩都是重要组成部分。本文使用Verilog对普遍应用的Baseline JPEG压缩核进行封装并在FPGA进行实现和验证,并给出了电路设计和测试结果。在Xilinx Spartan LX9 FPGA上,所实现的Baseline JPEG压缩器达到最高166 MHz的时钟频率。

GPS dynamic cycle slip detection and correction with baseline constraint

When the cycle slips take place in the attitude determination of a moving platform, the precision of the attitude will be impaired badly. A method of cycle slip detection and correction is proposed, which is suitable to the dynamic measurement using GPS carrier phase： the cycle slips detection is first achieved by triple difference observables, then the cycle slips correction is performed with baseline length constraint. The simulation results show that the proposed method is effective to the dynamic cycle slips problem.

Geochemical baseline determination and contamination of heavy metals in the urban topsoil of Fuxin City,China

Urban topsoil is the most frequent interface between human society and natural environment.The accumulation of heavy metals in the urban topsoil has a direct effect on residents'life and health.The geochemical baseline of heavy metals is an objective description of the general level of heavy metals in the urban topsoil.Meanwhile,the determination of geochemical baseline is necessary for regional environmental management,especially in coal cities prone to heavy metal pollution.Heavy metal pollution has become an environmental problem in Fuxin City,China for a long time.To establish the geochemical baseline of heavy metals in the topsoil of Fuxin City and to evaluate the ecological risk of the topsoil,we collected 75 topsoil samples(0–20 cm)and analyzed the concentrations of Cu,Ni,Zn,Pb,Cr,Cd,Hg and As through X-ray fluorescence spectrometry,atomic absorption spectrometry and inductively coupled plasma optical emission spectrometry.We determined the geochemical baseline of heavy metals in the topsoil of Fuxin City by using iteration removal,box-whisker plot,cumulative frequency curve and reference metal normalization;evaluated the contamination risk and ecological risk of the topsoil by using the baseline factor index,Nemerow index and Hakanson potential ecological risk index;and identified the source category of heavy metals in the topsoil by using a pedigree clustering heatmap.Results showed that the geochemical baseline values were 42.86,89.34,92.23,60.55,145.21,0.09,0.08 and 4.17 mg/kg for Cu,Ni,Zn,Pb,Cr,Cd,Hg and As,respectively.The results of Nemerow index and Hakanson potential ecological risk index indicated that the urban topsoil in the study area was slightly contaminated and suffering low potential ecological risk.The main contaminated areas dominated in the middle part and northeast part of the study area,especially in the western Haizhou Strip Mine.The result of baseline factor index indicated that Hg and Cd were the major pollution elements.Using a pedigree clustering heatmap,we divided the sources of these heavy metals into three types:type I for Ni and Cr,largely represented the enrichment of heavy metals from natural sources;type II for Cu,Pb,Zn,Cd and As,mainly represented the enrichment of heavy metals from anthropogenic sources;and type III for Hg,represented the form of both natural and anthropogenic inputs.

Baseline correction for digital strong-motion records by using the pre-event portion

Baseline offset in digital strong-motion acceleration record and initial velocity can produce unrealistic results for ground velocity and displacement derived from the acceleration by integration. A new method is proposed for the baseline correction and initial velocity calculation. It is based on linear least-squares fitting of the pre-event portion of velocity derived from the uncorrected acceleration data. Compared with the conventional method,which is based on removing the mean values of the pre-event portions of the acceleration and velocity traces,this method has clearer physical meaning and better stability.

P6软件在编制海外钢结构工程Baseline进度计划中的应用

随着近年来国内建筑行业的快速发展以及国际建筑公司的涌入,国内项目管理的国际化程度正在日益上升,国际上被广泛使用的专业项目管理软件P6(Primavera 6)在国内的使用也越来越多。借鉴海外项目运用成熟的国际化管理方法,对提升国内建筑行业管理效率、助推国内建筑企业走向世界舞台具有重要意义。以科威特国民银行项目为实例,介绍了P6软件在项目初期编制钢结构分部baseline进度计划中的应用。

The association between the baseline bone resorption marker CTX and incident dysglycemia after 4 years

Bone is an endocrine organ involved in modulating glucose homeostasis. The role of the bone formation marker osteocalcin （OCN） in predicting diabetes was reported, but with conflicting results. No study has explored the association between baseline bone resorption activity and incident diabetes or prediabetes during follow-up. Our objective was to examine the relationship between the baseline bone resorption marker crosslinked C-telopeptide of type I collagen （CTX） and glycemic dysregulation after 4 years. This longitudinal study was conducted in a university teaching hospital. A total of 195 normal glucose tolerant （NGT） women at baseline were invited for follow-up. The incidence of diabetes and prediabetes （collectively defined as dysglycemia） was recorded. A total of 128 individuals completed the 4-year study. The overall conversion rate from NGT to dysglycemia was 31.3%. The incidence of dysglycemia was lowest in the middle tertile [16.3% （95% confidence interval （CI）, 6.8%-30.70/0）] compared with the lower [31.0% （95% CI, 17.2%-46.1%）] and upper [46.5% （95% CI, 31.2%-62.6%）] tertiles of CTX, with a significant difference seen between the middle and upper tertiles （P = 0.002 5）. After adjusting for multiple confounding variables, the upper tertile of baseline CTX was associated with an increased risk of incident dysglycemia, with an odds ratio of 7.09 （95% CI, 1.73-28.99） when the middle tertile was the reference. Osteoclasts actively regulate glucose homeostasis in a biphasic model that moderately enhanced bone resorption marker CTX at baseline provides protective effects against the deterioration of glucose metabolism, whereas an overactive osteoclastic function contributes to an increased risk of subsequent dysglycemia.

Inaccuracy of Self-reported Low Sodium Diet among Chinese: Findings from Baseline Survey for Shandong & Ministry of Health Action on Salt and Hypertension(SMASH) Project

This study was aimed to evaluate the agreement between the self-reported sodium intake level and 24-h urine sodium excretion level in Chinese. The 24-h urine collection was conducted among 2112 adults aged 18-69 years randomly selected in Shandong Province, China. The subjects were asked whether their sodium intake was low, moderate, or high. The weighted kappa statistics was calculated to assess the agreement between 24-h urine sodium excretion level and self-reported sodium intake level. One third of the subjects reported low sodium intake level. About 70% of the subjects had mean 24-h sodium excretion 〉9 g/d, but reported low or moderate sodium intake.

Spectral baseline estimation using penalized least squares with weights derived from the Bayesian method

The penalized least squares(PLS)method with appropriate weights has proved to be a successful baseline estimation method for various spectral analyses.It can extract the baseline from the spectrum while retaining the signal peaks in the presence of random noise.The algorithm is implemented by iterating over the weights of the data points.In this study,we propose a new approach for assigning weights based on the Bayesian rule.The proposed method provides a self-consistent weighting formula and performs well,particularly for baselines with different curvature components.This method was applied to analyze Schottky spectra obtained in 86Kr projectile fragmentation measurements in the experimental Cooler Storage Ring(CSRe)at Lanzhou.It provides an accurate and reliable storage lifetime with a smaller error bar than existing PLS methods.It is also a universal baseline-subtraction algorithm that can be used for spectrum-related experiments,such as precision nuclear mass and lifetime measurements in storage rings.

Baseline characterization of patients aged 70 years and above with hepatocellular carcinoma

AIM: To characterize the baseline profiles of patients aged 70 years and above with hepatocellular carcinoma (HCC).METHODS: A series of 127 consecutive patients with HCC were enrolled between 2000 and 2004, and none of them had been diagnosed as having HCC previously. Baseline profiles, including parameters of hepatic function such as serum transaminase and prothrombin time [PT (% activity)] were compared between patients aged ≥70 and ＜70 years.RESULTS: Patients ≥70 years old showed significantly lower levels of aspartate aminotransferase (P = 0.04)and alanine aminotransferase (P = 0.01), and significantly higher PTs (P= 0.04) and platelet counts (P = 0.02).Concomitantly, among ≥70-year-old patients, HCC was more common in non-cirrhotics, whereas among patients ＜70 years old, HCC was more common in cirrhotics. There was no significant difference between the groups in the number or size of tumors.CONCLUSION: Older HCC patients showed less inflammation and better preservation of hepatic function, indicating that not only cirrhotic patients but also noncirrhotic patients should be considered as a high-risk group among the elderly.