简易烈度计记录的噪声水平评价:以泸定M_(S)6.8级地震为例

在我国地震预警和烈度速报系统中,烈度计被广泛使用。烈度计的频谱特征主要是通过检定实验室进行标定,但在破坏性地震中,烈度计响应特点缺少必要的研究分析。该文以2022年四川泸定M_(S)6.8级地震为例,对比分析了烈度计记录和强震仪记录在噪声水平、信噪比(signal-to-noise ratio,SNR)、高通滤波截止频率(f_(HP))取值以及有效周期范围(T_(max))方面的特点,综合评价了烈度计记录的频谱特征,分析了噪声影响。得到以下结论:在整个频域范围内,烈度计记录的SNR要比强震仪记录平均意义上低一个数量级,可以估计烈度计动态范围较强震仪大致低20 dB;烈度计记录的最佳f_(HP)取值相较于强震仪记录存在更大的不确定性,尤其是在竖直方向上;烈度计记录的最佳f_(HP)取值更大,反应谱T_(max)较传统强震仪记录在水平方向小1~2 s,在竖直方向小3 s左右。该研究结果有助于合理应用烈度计记录,服务地震学和地震工程学相关研究。

基于潮汐附加构造应力的2013年灯塔M_(S)5.1地震射出长波辐射变化分析

针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月15日)的ATSCTF变化。地震发生时,ATSCTF垂直方向分量处于高相位点附近,显示引潮力对本次正断层走滑型地震具有诱发作用。以ATSCTF变化周期的各低相位点时间(2012年12月19日、2013年1月4日、2013年1月18日、2013年2月2日)数据分别为背景,各周期期后数据分别与背景逐日相减,计算研究区(36°N~46°N,118°E~128°E)范围内,National Oceanic and Atmospheric Administration(NOAA)卫星射出长波辐射数据(Outgoing Long Wave Radiation,OLR)在各ATSCTF周期时段分布及其变化。结果显示,无震的ATSCTF变化的A、B、D周期,震中附近OLR无变化;发震的ATSCTF变化的C周期,在空间上,该地区震前OLR仅震中及其南侧区域发生了显著连续升高变化过程,在时间上经历了初始微异常→异常加强→高峰→衰减→发震→平静的演化过程,与岩石应力加载—破裂经历:初始微动破裂→扩张破裂→应力闭锁→地震爆发→平静的力学演化过程中各阶段红外辐射特征一致;显示引潮力对处于临界状态的活动断层具有诱发作用,而OLR是地震构造应力应变过程辐射表征。

Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview

The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first order with respect to time.The derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to zero.Derivatives are used to derive the wave equation.The differential wave equation is second order in time.Therefore,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave formation.This is important for calculating the generation of sound waves and water hammer waves.Therefore,the Euler continuity equation with finite time increments is of interest.The finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate tensor.This is a new branch in hydrodynamics.Quadratic and cubic invariants will be used in differential wave equations of the second and third order in time.

基于NaIO_(3)转化NaIO_(4)回用合成S-甘油醛缩丙酮及其寡聚研究

S-甘油醛缩丙酮是合成手性药物的重要中间体。以L-抗坏血酸为原料,经缩酮化,硼氢化钠还原,高碘酸钠氧化制得S-甘油醛缩丙酮,收率为46.8%;探讨了含碘酸钠母液转化成高碘酸钠以循环套用,回收率为83.90%;初步考察了S-甘油醛缩丙酮的聚合度与时间的关系,并推测其寡聚化合物的结构和反应机理;用^(1)H NMR、IR和LC-MS等对化合物结构进行表征。

1例藏族完全型Shone综合征患者的围术期护理

文章总结了1例藏族完全型Shone综合征患者的围术期护理经验。护理要点包括术前密切监测患者四肢血压,做好安全护理,预防晕厥、猝死等意外事件发生,术后加强肺康复护理,做好阶段性运动干预、疼痛护理、个体化饮食护理,同时全程做好多方位跨文化护理。经过精心治疗和护理,患者术后恢复良好,痊愈出院。

President's Expectations (Foreword to the periodical)

The rapid growth of IT industry in the information age has brought broad prospects to China and the world UESTC,an important research and innovation center of China,is now engaged in the implementation of the great strategic plans of"Strengthening the military power with Science

Progress of CACNA1S Gene and Hypokalemic Periodic Paralysis

CACNA1 S gene is the gene encoding L-type calcium channel αa-subunit. CACNA1 S gene mutations can cause hypokalemic periodic pa- ralysis （HOKPP）. The related research speculated that CACNA1 S gene was the candidate genes which affect meat quality traits. In the present ar- ticle, the biological characteristics of CACNA1 S gene, structure, genetic diseases and the research development were respectively reviewed so as to provide a reference for further research.

Noether's theorem for non-conservative Hamilton system based on El-Nabulsi dynamical model extended by periodic laws

This paper focuses on the Noether symmetries and the conserved quantities for both holonomic and nonholonomic systems based on a new non-conservative dynamical model introduced by E1-Nabulsi. First, the E1-Nabulsi dynamical model which is based on a fractional integral extended by periodic laws is introduced, and E1-Nabulsi-Hamilton＇s canoni- cal equations for non-conservative Hamilton system with holonomic or nonholonomic constraints are established. Second, the definitions and criteria of E1-Nabulsi-Noether symmetrical transformations and quasi-symmetrical transformations are presented in terms of the invariance of E1-Nabulsi-Hamilton action under the infinitesimal transformations of the group. Fi- nally, Noether＇s theorems for the non-conservative Hamilton system under the E1-Nabulsi dynamical system are established, which reveal the relationship between the Noether symmetry and the conserved quantity of the system.

What can the changes in shield resistance tell us during the period of shearer's cutting and neighboring shields' advance?

In order to determine the influence of shearer's cutting and neighboring shields' advance on the support resistance variation, leg pressure data of all 235 shields in the panel LW61 of Cumberland coal mine were analyzed. The results show that the relationship between the leg pressure increment and the distance from shield to front drum of shearer is a quadratic function and that the higher leg pressure increment before shield advance tends to be related to adverse roof conditions. In addition, the three proposed leg pressure increment-related parameters and the three traditional parameters(time-weighted average pressure, setting pressure, and final pressure) of approximately 32000 shield supporting cycles were calculated by a self-developed software package to analyze the correlation between them. The results show that there is a powerful connection between them, and that the three proposed leg pressure increment-related parameters could be used as the indexes to evaluate the interaction between shields and the roof, and to identify the periodic weighting.

Periodic Solutions for a Class of Neutral Functional Differential Equations with Distributed and Discrete Delays

Based on Krasnoselskii's fixed point theorem,matrix measure and functional analysis methods,some new sufficient conditions for the existence of periodic solutions of neutral functional differential equations with distributed and discrete delays are obtained. Moreover,we construct an example to illustrate the feasibility of our results.

Periodic Solution of n-Species Gilpin-Ayala Competition System with Impulsive Perturbations

The principle aim of this paper is to explore the existence of periodic solution of n-Species Gilpin-Ayala competition system with impulsive perturbations. Sufficient and realistic conditions are obtained by using Mawhin's continuation theorem of the coincidence degree. Further, some numerical simulations show that our model can occur in many forms of complexities including periodic oscillation and chaotic strange attractor.

Risk assessment of water security in Haihe River Basin during drought periods based on D-S evidence theory

The weights of the drought risk index （DRI）, which linearly combines the reliability, resiliency, and vulnerability, are difficult to obtain due to complexities in water security during drought periods. Therefore, drought entropy was used to determine the weights of the three critical indices. Conventional simulation results regarding the risk load of water security during drought periods were often regarded as precise. However, neither the simulation process nor the DRI gives any consideration to uncertainties in drought events. Therefore, the Dempster-Shafer （D-S） evidence theory and the evidential reasoning algorithm were introduced, and the DRI values were calculated with consideration of uncertainties of the three indices. The drought entropy and evidential reasoning algorithm were used in a case study of the Haihe River Basin to assess water security risks during drought periods. The results of the new DRI values in two scenarios were compared and analyzed. It is shown that the values of the DRI in the D-S evidence algorithm increase slightly from the original results of Zhang et al. （2005）, and the results of risk assessment of water security during drought periods are reasonable according to the situation in the study area. This study can serve as a reference for further practical application and planning in the Haihe River Basin, and other relevant or similar studies.

离散时间迭代的LCC-S型无线电能传输系统建模及稳定性分析

为了建立LCC-S型无线电能传输(WPT)系统的模型并分析其稳定性,采用离散时间迭代的思想,建立了开环控制模式下LCC-S型WPT系统的模型,该模型可以描述系统的连续动态特性。在此基础上,进一步推导了电压型比例积分控制LCC-S型WPT系统的离散时间迭代模型,同时利用Pade近似将延时时间纳入数字控制系统。基于雅可比矩阵特征根的稳定性分析评估了控制器参数、延时时间和主电路参数对系统稳定性的影响,准确预测了系统的稳定范围。同时利用特征根预测了系统不稳定时的振荡周期。然后,对稳定边界受控制器参数和主电路参数变化的影响进行了研究。此外,将LCC-S型WPT系统的EDF模型、GSSA模型和离散时间迭代模型进行临界稳定预测值的对比。最后,仿真和实验验证所建立模型和稳定性分析的正确性。

Marxism and the Subsidy Period in Vietnam （1975-1986）

Marxism was spread into Vietnam by patriotic intellectuals from the 20s of the 20th century and still exists until today. The presence of Marxism in Vietnam through such a long history is enough to prove its importmlce and strong influence in the socio-political life of Vietnam. First of all, Marxism is closely related to the movement of national liberation revolutions in Vietnam from the 20s to the mid 70s of the 20th century： Marxism, with its outright revolutionary nature, had most adequately and effectively met the urgent needs of national liberation revolutions in Vietnam at that time, and at the same time evoked the fierce belief of patriotic revolutionists in a noble ideal--tJle ideal of communist society, and encouraged them to devote themselves to national liberation revolutions. It can be said that Marxism has become the soul of national liberation revolutions in Vietnam; hence, the victory of such revolutions in the mid 70s of the 20th century is also the victory of Marxism in an Eastern country that was very obsolete then. Furthermore, Marxism is also associated with the reforming of old society and building of new society--the socialist society in Vietnam： after winning national independence and unification for the country in the mid-70s of the 20th century, Vietnamese patriotic revolutionists posed the question of＂What new model of society should be built in Vietnam to match the country＇s history context？＂ This question is not only related to the fate of of everyone, but also related to the fate of Vietnamese people as a whole. Marxism had brought to patriotic revolutionists and all Vietnamese people a very clear answer： the socialist society （the first phase of communist society）, where there will no longer be capitalist ownership, no people exploiting people, no rich and poor, from each according to his ability, to each according to his needs, all resources are of common ownership, etc Thus, from 1975 to 1986 （the subsidy period in Vietnam）, the Communist Party of Vietnam had led the people to begin reforming the old society and building new one nationwide with a very happy attitude and a strong belief in the future of socialist society. However, only when embarking on the construction of a new society did our party notice that the realization of an ideal model of society according to Marxism in an obsolete country which had just been out of wax like Vietnam （without any initial material premises, except a political party of the working class and labor population--the Communist Party of Vietnam） is a very difficult job. Therefore, the construction of socialist society in Vietnam in the early stage, from 1975 to 1986, ended in a severe social-economic crisis. Thus, Marxism had capitalized on its strengths in national liberation revolutions in Vietnam, helping Vietnamese people to be free from the domination of colonial counties and empires, but it also had adverse impacts on the reforming of old society and building of new society, which was reflected in the socioeconomic crisis in Vietnam during the 1975-1986 period. Here, the questions to be posed are,＂Has Marxism ended its historic mission for Vietnamese people？＂, or ＂How should Marxism be adjusted to be appropriate to the new historical context of Vietnam？＂ and ＂If such adjustments are needed, what will the prospects of Marxism in Vietnam be like？＂ This article will focus on answering those questions

SOLITARY WAVE AND PERIODIC WAVE SOLUTIONS FOR THE NON-NEWTONIAN FILTRATION EQUATIONS WITH NONLINEAR SOURCES AND A TIME-VARYING DELAY

This paper is concerned with the non-Newtonian filtration equations with non- linear sources and a time-varying delay. By an extension of Mawhin＇s continuation theorem and some analysis methods, several sufficient conditions ensuring the existence of solitary wave and periodic wave solutions are obtained. Some corresponding results in the literature are improved and extended. An example is given to illustrate the effectiveness of our results.

Factors influencing electromagnetic scattering from the dielectric periodic surface

The scattering characteristics of the periodic surface of infinite and finite media are investigated in detail.The Fourier expression of the scattering field of the periodic surface is obtained in terms of Huygens’ s principle and Floquet’s theorem.Using the extended boundary condition method(EBCM) and T-matrix method, the scattering amplitude factor is solved,and the correctness of the algorithm is verified by use of the law of conservation of energy.The scattering cross section of the periodic surface in the infinitely long region is derived by improving the scattering cross section of the finite period surface.Furthermore, the effects of the incident wave parameters and the geometric structure parameters on the scattering of the periodic surface are analyzed and discussed.By reasonable approximation, the scattering calculation methods of infinite and finite long surfaces are unified.Besides, numerical results show that the dielectric constant of the periodic dielectric surface has a significant effect on the scattering rate and transmittance.The period and amplitude of the surface determine the number of scattering intensity peaks, and, together with the incident angle, influence the scattering intensity distribution.

The Construction of a New Translation Ethics from the Perspective of Chinese Philosophy

As a cross-linguistic,cross-cultural,and cross-social activity,translation is affected by cultural moralities.Since the ethical standard of faithfulness has been abandoned by theories of cultural criticism and the power of translators’manipulation has been constantly exaggerated,the study of translation ethics is an effective remedy for a current dilemma in translation studies.It is a common phenomenon for some translators to erase the linguistic and cultural differences of Chinese literature by catering to target readers’reception.Social ethics is the foundation of a nation’s translation ethics,which means that thoughts from the Western world may not be suitable for the current situation in China.Learning from concepts of Chinese philosophy including harmony in diversity,seeking common ground while reserving differences,and honesty to formulate a new translation ethics will surely restrain translators’subjectivity within appropriate limits and develop world culture in more harmonious fashion.

Existence and Multiplicity of Periodic solutions for the Non-autonomous Second-order Hamiltonian Systems

In this paper,we study the existence and multiplicity of periodic solutions of the non-autonomous second-order Hamiltonian systems■where T> 0.Under suitable assumptions on F,some new existence and multiplicity theorems are obtained by using the least action principle and minimax methods in critical point theory.