WEAKLY ALGEBRAIC REFLEXIVITY AND STRONGLY ALGEBRAIC REFLEXIVITY

Algebraic reflexivity introduced by Hadwin is related to linear interpolation.In this paper,the concepts of weakly algebraic reflexivity and strongly algebraic reflexivity which are also related to linear interpolation are introduced.Some properties of them are obtained and some relations between them revealed

血清suPAR、BDNF、sTWEAK水平与类风湿关节炎患者疾病活动度及骨密度的相关性

目的研究血清可溶性尿激酶型纤溶酶原激活剂受体(suPAR)、脑源性神经营养因子(BDNF)、可溶性肿瘤坏死因子样细胞凋亡弱诱导因子(sTWEAK)水平与类风湿关节炎患者疾病活动度及骨密度的相关性。方法选取2021年1月至2023年7月解放军联勤保障部队第九四○医院内分泌科收治的类风湿关节炎患者140例为类风湿关节炎组,以及2021年1月至2023年7月至本院体检中心体检健康者70例为对照组。评估患者组疾病活动度,测定骨密度。检测对照组和类风湿关节炎组的血清suPAR、BDNF、sTWEAK水平。根据疾病活动度水平将类风湿关节炎组患者再分为低度亚组(2.6~3.2)、中度亚组(3.2~5.1)、高度亚组(>5.1)。比较类风湿关节炎组与对照组、3个亚组的suPAR、BDNF、sTWEAK、骨密度;分析suPAR、BDNF、sTWEAK与疾病活动度、骨密度的相关性;分析suPAR、BDNF、sTWEAK联合检测在预测疾病加重风险中的价值。结果类风湿关节炎组血清suPAR、BDNF、sTWEAK高于对照组(P<0.05)。高度亚组血清suPAR、BDNF、sTWEAK明显大于中度亚组和低度亚组(P<0.05),中度亚组血清suPAR、BDNF、sTWEAK明显大于低度亚组(P<0.05)。类风湿关节炎组前臂远端、腰椎L1-4、股骨颈、髋关节的骨密度小于对照组(P<0.05)。高度组前臂远端、腰椎L1-4、股骨颈、髋关节骨密度明显小于中度亚组和低度亚组,中度亚组前臂远端、腰椎L1-4、股骨颈、髋关节骨密度明显小于低度亚组(P<0.05)。血清suPAR、BDNF、sTWEAK与疾病活动度呈正相关,与前臂远端、腰椎L1-4、股骨颈、髋关节的骨密度呈负相关(P<0.05)。联合suPAR、BDNF、sTWEAK三项指标预测疾病活动度升高风险的AUC大于单独预测的AUC(P=0.000)。结论类风湿关节炎患者suPAR、BDNF、sTWEAK与疾病活动度呈正相关,与骨密度呈负相关,联合检测suPAR、BDNF、sTWEAK可为预测患者疾病未来变化趋势提供有效指导。

Modification of rock mass rating system:Interbedding of strong and weak rock layers

Rock mass classification systems are the very important part for underground projects and rock mass rating(RMR) is one of the most commonly applied classification systems in numerous civil and mining projects. The type of rock mass consisting of an interbedding of strong and weak layers poses difficulties and uncertainties for determining the RMR. For this, the present paper uses the concept of rock bolt supporting factor(RSF) for modification of RMR system to be used in such rock mass types. The proposed method also demonstrates the importance of rock bolting practice in such rock masses. The geological parameters of the Shemshak Formation of the Alborz Tunnel in Iran are used as case examples for development of the theoretical approach.

ON NUMBER OF LIMIT CYCLES FOR THE QUADRATIC SYSTEMS WITH A WEAK FOCUS AND A STRONG FOCUS

It is proved that the quadratic system with a weak focus and a strong focus has at most one limit cycle around the strong focus, and as the weak focus is a 2nd order(or 3rd order) weak focus the quadratic system has at most two(one) limit cycles which have (1,1) distribution ((0,1) distribution).

P-kernel Normal Systems in Weakly P-inversive Semigroups

In this paper, we first give the concept of weakly P-inversive semigroup S（P）. Then we describe the strong P-congruences on S（P） in terms of their P-kernel normal systems. It is proved that there is a bijection between the strong P-congruences and the P-kernel normal systems. Finally, it is also prove that the lattice of strong P-congruences and the lattice of P-kernel normal systems on S（P） are isomorphic.

THE FIRST BOUNDARY VALUE PROBLEM FOR STRONGLY DEGENERATE QUASILINEAR PARABOLIC EQUATIONS IN ANISOTROPIC SOBOLEV SPACES

This article concerns the existence of weak solutions of the first boundary value problem for a kind of strongly degenerate quasilinear parabolic equation in the anisotropic Sobolev Space. With the theory of anisotropic Sobolev spaces an existence result is proved.

Global existence of weak solutions to a prey-predator model with strong cross-diffusion

Using finite differences and entropy inequalities, the global existence of weak solutions to a multidimensional parabolic strongly coupled prey-predator model is obtained. The nonnegativity of the solutions is also shown.

Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. I: Deduction and geometric illustration

Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differentials of unitary indeterminate forms. The fruit of this work is going to be reported in three parts. The first part presents the standard analysis on this subject which supplements, systematizes and advances L. Hospital抯 principles on differential calculus by applying special ,general, and limit guaranteeing theories together with K(t) and XhK0 theories. The combination of theoretical analysis and geometric signification makes the derivation intuitional, visual and easy to perceive.

Checking weak and strong optimality of the solution to interval convex quadratic program

In this paper,we investigate three canonical forms of interval convex quadratic pro-gramming problems.Necessary and suficient conditions for checking weak and strong optimality of given vector corresponding to various forms of feasible region,are established respectively.By using the concept of feasible direction,these conditions are formulated in the form of linear systems with both equations and inequalities.In addition,we provide two specific examples to illustrate the efficiency of the conditions.

New iterative schemes for strongly relatively nonexpansive mappings and maximal monotone operators

In this paper, some new iterative schemes for approximating the common element of the set of fixed points of strongly relatively nonexpansive mappings and the set of zero points of maximal monotone operators in a real uniformly smooth and uniformly convex Banach space are proposed. Some weak convergence theorems are obtained, which extend and complement some previous work.

A Strong Stability Preserving Analysis for Explicit Multistage Two-Derivative Time-Stepping Schemes Based on Taylor Series Conditions

High-order strong stability preserving(SSP)time discretizations are often needed to ensure the nonlinear(and sometimes non-inner-product)strong stability properties of spatial discretizations specially designed for the solution of hyperbolic PDEs.Multi-derivative time-stepping methods have recently been increasingly used for evolving hyperbolic PDEs,and the strong stability properties of these methods are of interest.In our prior work we explored time discretizations that preserve the strong stability properties of spatial discretizations coupled with forward Euler and a second-derivative formulation.However,many spatial discretizations do not satisfy strong stability properties when coupled with this second-derivative formulation,but rather with a more natural Taylor series formulation.In this work we demonstrate sufficient conditions for an explicit two-derivative multistage method to preserve the strong stability properties of spatial discretizations in a forward Euler and Taylor series formulation.We call these strong stability preserving Taylor series(SSP-TS)methods.We also prove that the maximal order of SSP-TS methods is p=6,and define an optimization procedure that allows us to find such SSP methods.Several types of these methods are presented and their efficiency compared.Finally,these methods are tested on several PDEs to demonstrate the benefit of SSP-TS methods,the need for the SSP property,and the sharpness of the SSP time-step in many cases.

Strong and Weak Property of Travelling Wave Front Solutions for a Class of Degenerate Parabolic Equations

In this paper we study the strong and weak property of travelling wave front solutions for a class of degenerate parabolic equations. How the strong and weak property changes under the effects of wave speed and reaction diffusion terms are showed.

Key Technical Points of Wheat Moisture-resistant Strain Sowing and Management of Promoting Seedlings from Weak to Strong in Daiyue District

According to the meteorological conditions of sowing period and the characteristics of seedling in each key growth period,the measures of rushing drainage,rushing harvest stubble,rushing sow,implementing late sowing,strengthening field management before winter and in spring are taken in Daiyue District during the autumn planting period of wheat,which reduce the influence of natural disasters and increase the yield of wheat.

DIRECT TITRATION OF VERY WEAK ACIDS(BASES)IN AQUEOUS SOLUTION WITH STRONG BASES(ACIDS)USING VISUAL END-POINT INDICATION WITHOUT INDICATOR

This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indicator needed as well as good precision.

Rational Identification of Lightning Derivative Disasters by Strong Convective Weather Monitoring Data in Southern China——A Case Study in Guangzhou Development Region

Analytic method and identification direction for rational identification of lightning derivative disasters by strong convective weather monitoring data in southern China were introduced. Taking identification cases of lightning disaster in Guangzhou Development Region as the background,according to the characteristics in the region that large high-precision enterprises were more,lightning derivative disasters occurred frequently in thunderstorm season,and the actual situation that time of the affected enterprise applying for lightning disaster scene identification lagged,combining Technical Specifications of Lightning Disaster Investigation（ QX / T103-2009）,qualitative analysis method of lightning derivative disaster was put forward under the weather condition of strong convection in southern China by using weather monitoring data（ Doppler sounding radar data,lightning positioning monitoring data,atmospheric electric field data,rainfall data,wind direction and force）,and was optimized by technical means（ ＂ metallographic method＂ and ＂ remanence law＂）. The research could put forward efficient and convenient analytical thinking and method for lightning derivative disaster,and further optimize accuracy and credibility of lightning disaster investigation.

INTERACTION OF STRONG AND WEAK SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL SPACE

In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the bicharacteristics bearing weak singularities we proved a theorem on regularity propagation across the shock front.

STRONG DERIVATIVE AND ITS CONSEQUENCES

ＳＴＲＯＮＧＤＥＲＩＶＡＴＩＶＥＡＮＤＩＴＳＣＯＮＳＥＱＵＥＮＣＥＳ￥ＹａｎｇＫｅｒｅｎ；ＬｕＳｈｉｐａｎ（ＪｉｍｅｉＴｅａｃｈｅｒｓＣｏｌｌｅｇｅＸｉａｍｅｎ３６１０２１）Ａｂｓｔｒａｃｔ：Ｗｅｉｎｔｒｏｄｕｃｅｓｔｒｏｎｇｄｅｒｉｖａｔｉｖｅ，ｔ...

部分包覆钢-混凝土组合梁柱节点抗震性能试验研究

为研究不同连接构造的部分包覆钢-混凝土组合梁柱节点(PEC梁柱节点)的抗震性能,对2个PEC梁柱节点试件进行了拟静力加载试验,研究了低周往复荷载作用下PEC梁柱节点试件的破坏现象、滞回曲线、骨架曲线、延性、耗能能力和刚度退化等抗震性能。结果表明:强轴连接PEC梁柱节点的滞回曲线呈梭形和弓形,在达到极限承载力后仍能保持一定的延性和耗能能力;弱轴连接PEC梁柱节点牛腿与梁间的焊缝处发生破坏,未展现出预期的耗能能力,PEC梁仍在弹塑性状态,没有达到极限状态;PEC梁柱节点核心区混凝土替换为加劲肋板后,试件仍具有较好的承载力、延性和耗能能力,刚度退化规律无明显变化,且强轴连接节点与弱轴连接节点刚度变化规律基本一致;PEC柱牛腿设计过短会导致焊缝连接处断裂,试件延性和耗能能力得不到发挥,剩余刚度较大。

鄂尔多斯盆地本溪组碎屑障壁海岸砂体微相南北变化

在延长探区近1500口钻井资料的基础上,进行大量岩心和薄片观察以及砂厚和砂地比统计,探究鄂尔多斯盆地本溪组的砂体微相类型、平面形态和分布的沿岸变化及其控制因素。结果表明,延长气田本溪组总体均为中小潮差环境下的陆源碎屑障壁海岸沉积,但南部的甘泉—富县地区波浪作用较弱,形成了典型的障壁砂坝和障壁后沉积。北部延安—靖边南地区波浪作用较强,形成了改造障壁、浅滩和下切谷充填潮道3种主要微相砂体。障壁砂体呈平行岸线的带状或串珠状排列,近源和近岸分布;浅滩砂体呈多个分散的卵圆形远源远岸分布;潮道带砂体充填则受控于古地貌凹槽。该研究结果对延长气田和类似环境的储层识别和评价具有重要的指导意义。