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1.
宋秀艳 《海外英语》2012,(8):262-265
Since Brown and Gilman pioneered the concepts of power and solidarity in 1960 and because of people’s continued research in them,the two terms have been fundamental to sociolinguistic theory.What are the pragmatic functions of them? In order to answer the question,an analysis of power and solidarity is conducted in view of deictic terms,address terms,verb patterns,code-switching and style variation and it tries to probe into the pragmatic functions of power and solidarity on the basis of Jakobson’s theory of language functions.  相似文献   

2.
This paper presents the research on the atmospheric corrosion rates of carbon steel, zinc and copper in Chongqing, which was a corrosion subprogram of an international project, Regional Air Pollution in Developing Countries. We performed field exposure tests of carbon steel, zinc and copper at an urban site Guanyinqiao and a rural site Tieshanping inChongqing, then used grey relational analysis, based on the database of the whole corrosion project, to determine the order of the effect of environmental factors on corrosion rates of tested metals, and established dose-response functions for these three metals. The results showed that the two crucial agents of acidic environment, SO2 and H , were common factors that contributed most to the corrosion of the tested metals. The established dose-response functions for outdoor carbon steel and zinc are proved applicable to use in Chongqing, but the function for copper needs further modifying. We employed these dose- response functions and general environmental data to elaborate the maps of corrosion rate respectively of carbon steel and zinc by geological information system (GIS) technique which help to identify areas of high corrosion damage risk. An acceptable annual average SO2 level of 21 μg/m3 for carbon steel and that of 61 μg/m3 for zinc are also put forward to control the air pollution impact on atmospheric corrosion in Chongqing urban areas.  相似文献   

3.
The asymptotic theory for nonlinear transformations of fractionally integrated time series is developed.By the use of fractional Occupation Times Formula,various nonlinear functions of fractionally integrated series such as ARFIMA time series are studied,and the asymptotic distributions of the sample moments of such functions are obtained and analyzed.The transformations considered in this paper includes a variety of functions such as regular functions,integrable functions and asymptotically homogeneous functions that are often used in practical nonlinear econometric analysis.It is shown that the asymptotic theory of nonlinear transformations of original and normalized fractionally integrated processes is different from that of fractionally integrated processes,but is similar to the asymptotic theory of nonlinear transformations of integrated processes.  相似文献   

4.
Introduction Let f and g be two meromorphic functions defined in the open complex plane C, and k be a nonnegative integer or infinity. For {}aC违U, denote by (;)kEaf the set of all a-points of f where an a-point of multiplicity m is counted m times if mk and otherwise k+1 times. If (;)(;)kkEafEag=, then, f and g are considered to share the value a with weight k, which is expressed by f and g share (a ,k). Clearly if f and g share (a ,k), then they share (a ,p) for all integer p in 0pk#. It…  相似文献   

5.
We construct the membership functions of the fuzzy objective values of a controllable queueing model, in which cost elements, arrival rate and service rate are all fuzzy numbers. Based on Zadeh's extension principle, a set of parametric nonlinear programs is developed to find the upper and lower bounds of the minimal average total cost per unit time at the possibility level. The membership functions of the minimal average total cost are further constructed using different values of the possibility level. A numerical example is solved successfully to illustrate the validity of the proposed approach. Because the object value is expressed and governed by the membership functions, the optimization problem in a fuzzy environment for the controllable queueing models is represented more accurately and analytical results are more useful for system designers and practitioners.  相似文献   

6.
This paper deals with the combination of point phonon and phason forces applied in the interior of infinite planes and half-planes of 1D quasicrystal bi-materials. Based on the general solution of quasicrystals, a series of displacement functions are adopted to obtain Green's functions for infinite planes and bi-material planes composed of two half-planes in the closed form, when the two half-planes are supposed to be ideally bonded or to be in smooth contact. Since the physical quantities can be readily calculated without the need of performing any transform operations, Green's functions are very convenient to be used in the study of point defects and inhomogeneities in the quasicrystal materials.  相似文献   

7.
The maximally holomorphic functions of a bounded linear operator is introduced and applied to representthe spectrum and characterize the single--valued extension property. The well known results of quasi--nilpo-tent equivalent operators follow easily from the relation of their maximally holomorphie functions.  相似文献   

8.
In this study,we examined the protective effects of Danshen both on endothelial progenitor cells(EPCs) in patients with hypercholesterolemia and on in-vitro EPCs of healthy volunteers.In the clinical study,we randomly divided 24 subjects with hypercholesterolemia into two groups(the control group and the Danshen-treated group).At the end of two weeks of treatment,the EPC cellular functions of both groups were tested.The results indicated that,compared to the control group,EPCs in the Danshen-treated group showed significantly better cellular functions,which was manifested in the cloning number,the proliferation capacity,the number of EPC adhesions,and cell migration.In the subsequent in-vitro experiments,EPCs were treated with vehicle,oxidized low-density lipoprotein(Ox-LDL,100 μg/ml),or Ox-LDL(100 μg/ml) plus different concentrations of Danshen(Danshensu 2,10,or 50 μg/ml,respectively) for 24 h.The results showed that Danshen treatments can prevent the detrimental effects of Ox-LDL on EPC cellular functions measured by proliferation capacity(0.24±0.08,0.37±0.11,0.30±0.04 vs.0.13±0.02,P0.05,P0.01,and P0.01,respectively),and adhesion ability(63.00±11.60,70.00±10.80,85.50±11.41 vs.40.50±6.85,all P0.01).Compared to the group treated with Ox-LDL alone,Danshen treatment significantly decreased the lipid peroxidation end product malondialdehyde(MDA) [(4.34±0.54),(3.98±0.47),(3.46±0.31) vs.(5.57±0.64) nmol/ml,all P0.01],increased the production of superoxide dismutase(SOD) [(29.74±0.71),(31.09±0.83),(30.41±0.65) vs.(14.76±3.99) U/ml,all P0.01],and lowered the expression of interleukin-6(IL-6) [(24.62±7.69),(27.04±3.14),(33.38±18.86) vs.(230.67±33.53) pg/ml,all P0.01] and tumor necrosis factor-α(TNF-α) [(41.72±6.10),(17.02±6.82),(3.73±2.26) vs.(228.71±41.53) pg/ml,all P0.01] in Ox-LDL treated EPCs.These results suggest that Danshen may exert a protective effect through its antioxidant and anti-inflammatory features.  相似文献   

9.
The uniqueness of meromorphic fuctions sharing one value was studied. Using the concept of weighted sharing, we proved the following theorem. For two meromorphic functions f and g which are not polynominals of degree less than a positive integer k, if f nf (k) and g ng (k) share (1,2), where n is another positive integer not less than k 10, then f nf (k) identically equals g ng (k) or f nf (k)g ng (k) identically equals 1. Particularly for k =1, we improved the results of Yang [Yang CC, Hua XH, Uniqueness and value-sharing of meromorphic functions, Annales Academi? Scientiarum Fennic? Mathematica, 1997, 22: 395-406], and Fang [Fang ML, Hua XH, Entire function that share one value, Journal of Nanjing University, 1996, 13(1): 44-48. (In Chinese)].  相似文献   

10.
We solve the problem of petroleum products distribution through oil pipelines networks. This problem is modelled and solved using two techniques: A heuristic method like a multiobjective evolutionary algorithm and Mathematical Programming. In the multiobjective evolutionary algorithm, several objective functions are defined to express the goals of the solutions as well as the preferences among them. Some constraints are included as hard objective functions and some are evaluated through a …  相似文献   

11.
研究了非线性三阶两点边值问题u(t)+λ[h(t)f(t,u(t))+g(t,u(t))]=0,00,此问题存在一个正解.  相似文献   

12.
通过构造辅助函数和利用最大值原理,得到了非线性抛物方程(g(u))t=▽.(a(u)b(x)c(t)▽u)+h(t)f(u)的解的爆破和整体存在的充分条件,给出了爆破时间的上界和爆破速率的上估计以及整体存在解的上估计.  相似文献   

13.
主要研究了函数图象的盒维数。通过定义函数图象,并给出函数图象的盒维数,从而在dim BΓ(f,I),dim BΓ(g,I),dim BΓ(f±g,I)之间建立结合关系。  相似文献   

14.
This study examines the nature and process of ninth grade students conceptual change regarding their mental model of dissolution and diffusion as a result of instructions using the Dual Situated Learning Model (DSLM). The dual situated learning events of this model are designed according to the students ontological viewpoint of the science concepts as well as the nature of these concepts. Moreover, these events serve two functions by creating dissonance with the pre-existing knowledge and providing new schema for constructing a more scientific view of the concept. The concepts of dissolution and diffusion were chosen to examine students conceptual change process because they involve the understanding of both invisible and process attributes. Results indicate that about 76%–90% of the students successfully underwent a change in their understanding of the concepts of dissolution and diffusion after instruction using dual situated learning events. Moreover, about 75% of the students successfully applied their previous mental sets into the challenging situated learning event. This current study demonstrates that DSLM indeed facilitates the processes of conceptual change and knowledge acquisition involving concepts of dissolution and diffusion, clarifying the nature of conceptual change involving science concepts of both an invisible and a process nature.  相似文献   

15.
刘克笑 《安康学院学报》2010,22(5):94-96,99
研究全纯函数与其微分多项式分担函数,得到了如下的正规定则:设F是区域D内的全纯函数族,k是一正整数,h1(z),h2(z)在区域D内的解析,满足|h1(z)|2+|h2(z)|2≠0。若f∈F,f的零点重级至少为k,且f(z)=0|f(k)(z)|≤M(常数M〉0),(z)=αi(z)L(Z)=αi(z),i=1,2,其中L(z)=f∞(z)+α1(z)f(k-1)(z)+…+αk(z)f(z)为f的微分多项式,αi(z)(i=1,2,…,k,k≥1)在D内解析,那么F在D内正规。  相似文献   

16.

Background

This study was designed to extend our understanding of phonology and reading to include suprasegmental awareness using measures of prosodic awareness, which are complex tasks that tap into the rhythmic aspects of phonology. By requiring participants to access, reflect on and manipulate word stress, the prosodic awareness measures used here necessarily impose demands on the executive system. Prosodic awareness was evaluated as a phonological predictor of reading in older readers while controlling for executive functions (EF) in order to ascertain whether observed predictive relationships could be confidently attributed to suprasegmental awareness.

Methods

103 adults between 18 and 55 years of age completed tasks on prosodic awareness, EF, vocabulary, nonverbal abilities, naming speed and short‐term memory.

Results

Independent contributions of prosodic awareness added to models of word reading, whereas EF processes did not uniquely contribute to adult reading outcomes.

Conclusions

Suprasegmental phonology explains individual differences in word reading among experienced readers. Theoretical implications of findings are discussed.

Implications for Practice

What is already known about this topic
  • Phonological awareness (PA) becomes less predictive of reading in older readers. PA is typically assessed at the level of the segment (e.g., phonemes, syllables and onset‐rimes), with less focus on suprasegmental processes (e.g., rhythm, stress and intonation).
  • Suprasegmental phonological processing includes measures of prosodic ability (e.g., awareness and manipulation of suprasegmental features of oral language). Studies on prosodic awareness and reading have independent contributions beyond segmental PA in early readers. Less work has been investigated among adult readers.
  • Executive functions (EF) including inhibitory control, working memory, switching and updating and monitoring of goal directed behaviour, predict overall academic achievement. Limited studies have controlled for EF demands in phonological tasks.
What this paper adds
  • Tasks of prosodic awareness necessarily impose demands on the executive system when manipulating components of oral language. After controlling for EF and controls, prosodic awareness explained individual differences in adult word reading.
  • Tasks of suprasegmental phonological processes explain the association between phonology and reading in older and more experienced readers. Researchers who explore phonology and reading development should begin to include tasks of prosodic awareness to examine the dual role of segmental and suprasegmental PA as it is implicated across development.
Implications for theory, policy or practice
  • Theoretical models of phonology and reading can be extended to include suprasegmental processes.
  • For educational practitioners involved in reading assessment of older readers, tasks of prosodic awareness are a more age‐appropriate measure of phonology.
  • Tasks of phonology and reading with increasing complexity impose greater demands on the executive system. The relationship between cognitive flexibility and reading needs to be considered in theoretical models of reading.
  相似文献   

17.
通过盐度(32‰、28‰、24‰、20‰、16‰)对三倍体和二倍体太平洋牡蛎Crassostrea gigas呼吸和排泄影响比较的研究表明:在盐度32‰20‰,牡蛎的耗氧率随着盐度降低而降低,在盐度20‰时耗氧率最低,三倍体耗氧率平均为1.345 mg/(g?h),二倍体为1.679 mg/(g?h),之后随盐度降低耗氧率稍有升高。在相同条件下,三倍体和二倍体太平洋牡蛎排氨率出现不同程度升高,在盐度20‰达到最高,三倍体排氨率平均为530.256μg/(g?h),二倍体为360.765μg/(g?h),之后随盐度降低排氨率大幅度降低。以体重为协变量进行协方差分析结果表明:盐度、倍性效应引起耗氧率差异达到显著水平(p<0.01),二倍体太平洋牡蛎耗氧率大于三倍体,盐度引起排氨率差异极显著(p<0.01),倍性效应引起的排氨率差异不显著。  相似文献   

18.
在前期研究的基础上,进行了强聚硒酵母发酵罐扩大培养条件的优化,最终确定发酵罐中最适发酵条件:麦芽汁1%,初始硒浓度为15μg/mL,在其发酵进入到对数生长期后再添加亚硒酸钠使之硒浓度达到25μg/mL,种子培养时间12 h,接种量为10%,培养温度28℃,通气量6 L/h,搅拌速度150 r/min,培养时间29 h。在此最优化条件下,酵母生物量达到8.05 g/L,硒含量达到1 003.19μg/g。  相似文献   

19.
The uniqueness problem of entire functions sharing one small function was studied. By Picard’s Theorem, we proved that for two transcendental entire functions f (z) and g(z), a positive integer n≥9, and a(z) (not identically eaqual to zero) being a common small function related to f (z) and g(z), if f n(z)(f(z)-1)f′(z) and gn(z)(g(z)-1)g′(z) share a(z) CM, where CM is counting multiplicity, then g(z) ≡ f (z). This is an extended version of Fang and Hong’s theorem [ Fang ML, Hong W, A unicity theorem for entire functions concerning differential polynomials, Journal of Indian Pure Applied Mathematics, 2001, 32 (9): 1343-1348].  相似文献   

20.
建立了二维依坐标(h-m)-凸函数的Hermite-Hadamard型不等式,推广了二维依坐标凸函数、二维依坐标s-凸函数(第二种意义下)、二维依坐标m-凸函数与二维依坐标h-凸函数情形下的Hermite.Hadamard型不等式.  相似文献   

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