a r X i v :p h y s i c s /0602002v 1 [p h y s i c s .a c c -p h ] 1 F e
b 2006RADIATION OF RELATIVISTIC PARTICLES FOR QUASIPERIODIC MOTION IN A
TRANSPARENT MEDIUM
S.Bellucci 1and V.A.Maisheev 21INFN -Laboratori Nazionali di Frascati,P.O.Box 13,00044Frascati,Italy
2Institute for High Energy Physics,142281,Protvino,Russia
The radiation of relativistic charged particles for the quasiperiodic motion in a transparent medium is considered.For motion of the general kind the di?erential probability of the process is obtained.For planar motion the spectral intensity of radiation is found.The di?erent cases of radiation in the medium-?lled undulators are studied.In particular,the in?uence of Cherenkov radiation on the undulator one is discussed.PACS number(s):41.60.-m I.INTRODUCTION At the present time such power sources of x-rays as undulators [1]are widely used in various ?elds of science.In a number of papers [2,3,4,5,6,7,8,9],with the aim of increasing of the energy of emitted photons,the crystal undulator was considered.The recent paper[10]contains a rather complete list of references related to various problem of crystal undulators [11].One of the proposed constructions [13,14]was created and tested in a positron beam.Preliminary results of the experiment [15]give an indication on the observation of undulator radiation.Calculations of the expected intensity for this experiment were based on the theory [16]of radiation for quasiperiodic motion in vacuum.This theory allows one to perform the calculation of radiation spectra for motion of the general type and di?erent parameters of the undulator.In calculations with our experimental conditions we use the theory [16]in the frame of the classical electrodynamics.However,in the recent papers [17,18]the possibility of an appreciable in?uence of the medium polarization on the spectral intensity in crystal undulators was shown.In Ref.[17]the process was considered only in the dipole approximation.In Ref.[18]this process was studied for a speci?c construction of the undulator and hence for speci?c trajectories of particles.In both cases the radiation of the ?rst harmonic was considered.In this paper we want to extend the theory [16]to the case of a transparent medium.We will study the pointed process in the general case of dielectric function ε(ω)(where ωis the frequency or energy of the emitted photon),which may be larger or smaller than 1.The arising phenomena in di?erent cases will be shortly discussed.In this paper we employ units such that ˉh =c =1.Note that a large number of problems of radiation for charged particles moving in various media were considered in Ref.[19].Here the investigations of the radiation in medium-?lled undulators are also presented.However,these results concern mainly the total radiation intensity.We also point out the paper [20]where the radiation for quasiperiodic motion was studied in a wide range of undulator parameters.II.RADIATION ENERGY LOSSES OF PARTICLE The well-known formula [21,22]for the radiation energy losses of a moving particle takes into account the dielectric function of the medium.The analogous formula in [16]di?ers from the above pointed one and was obtained for the vacuum.With the aim of extending of the theory [16](in the frame of the classical electrodynamics)to the case of a transparent medium we should ?nd its corresponding representation.
The Fourier transform of the vector potential for the electromagnetic ?eld of a charged particle moving in the isotropic transparent medium has the following form [22]:
A (ω,r )=e exp [ikr ]
εωn ,ε(ω)is the dielectric function (εis a real positive value),n is the unit vector in the direction of
the photon motion,v ,r 0are the particle velocity and its radius-vector,r is the distance from the point,where the particle (with the charge e)is located in the moment of time t .This relation is valid for large r .
Using this equation we ?nd (analogously to [16])the magnetic and electric (E )?elds.The radiated energy d E (n ,ω)in an elementary solid angle d ?and a frequency range ω,ω+dωfor the whole time of the process is [23]d E (n ,ω)=
√
Finally,we obtain
d E(n,ω)=e2
√
(2π)2
dt1dt2.(3)
This equation describes the di?erential radiation energy losses of the relativistic particle moving in a transparent medium.At
√
ε(v2?1/ε)T mδ(ω?√2π,(4)
where T m is the time of a particle motion andθis the polar angle,which determined by the pair of vectors:v and n. From here,we get the intensity of radiation per unit time
d E(ω)
εωnr0(t),?0=ωT(1?
√
v2
⊥
γ2)/(2γ2),v ≈1?(1+v2⊥γ2)/(2γ2),(8) where
ε
ω2dωd?
ε=1+(
√
εnr0ω=?χωt+√
2
+
t
?0/T=ω(?χ+
√v2⊥γ2)εθ2
εω2dωd?
ω0γ2
∞
n=?∞δ(?0?2πn)[{(ε?1)4γ2?1}|I0|2+γ2(|I⊥|2?ReI?0I )],(12)
I0= 2π0e if(ψ)dψ,I⊥= 2π0v⊥(ψ)e if(ψ)dψ,(13)
I = 2π0v⊥2(ψ)e if(ψ)dψ,ψ=ω0t,(14)
f(ψ)=nψ+ω
√εnx
⊥
(ψ),(15)
where
?(t)=ω0 t0(v2⊥(t′)?
√ε),(17)
θ2=1
√√
v2⊥.Obviously,these relations are not independent and we write them for convenience of the further
discussion.
Eqs.(12)-(15)describe the spectral-angular distribution of the relativistic particle radiation for the quasiperiodic motion in the transparent and isotropic medium.The trajectory of the particle are represented in these equations in a general form.Eqs.(12)-(15)allow us to calculate the spectral(integrated over angular variables)intensity,with the help of numerical methods,for any particle motion.However,for some general enough cases the integrals in Eqs.(13)-(15)may be taken over angular variables so as,for example,in the important case of the planar motion.For the planar motion
nx⊥=θcos(?) t0v⊥(t′)dt′,(19) where?is the azimuthal angle.After integration overθwe get
dI p=e2ωdωd?
ε
γ2+
1
dω=?
e2ω
ε t1t2dψg(ψ) ε?ξ(1+ρ/2?2χγ2/√
ε
γ2+
1
εξρ/2)(t1?t2)+√
dω
=e2ω
∞
n=?∞,=0?(θ2)|x n|2{n2?2[ε?(ε?1)γ2][ξ(n/√ε))]},(22)
where x n=(1/(2π) π?πx(ψ)exp(?inψ)dψis the Fourier component of the value x(t)=1/γ t0g(ψ)dψ(x(t)/ω0is the transversal coordinate).This equation was obtained for the two conditions:εω2θ2ρ/γ2?1andρ√
ε>1+ρ/2(23) the following term(n=0)should be added in Eq.(22):
dI n=0
ε+
1
γ2
)?(
(ε?1)γ2
4γ2?1)[2εξ2(2χγ2
√X2},(24)
where
ε<1+ρ/2only positive numbers n are possible.
IV.EXAMPLES OF CALCULATIONS
In this section we point out the basic peculiarities of the radiation for quasiperiodic particle motion in the medium. For the detail description of this process the knowledge of explicit form of the dielectric function is important.The aim of our consideration is the application of the equations obtained in the previous section to the calculations of radiation processes in a transparent medium.Note that many peculiarities of similar processes were discussed in earlier papers[17,18,19,20,25,26,31,32,33]
In the general case the relations obtained here for radiation in a medium are valid,at the condition of a small in?uence of this media on the quasiperiodic particle motion.The di?erent processes(multiple scattering,ionization energy losses and others)can modify the motion of particles and they should be investigated separately.Various examples of consideration of this problem can be found in the literature[16,22,24].One can assert that,in the case of small enough values of|ε?1|,the in?uence of the medium on the motion will be insigni?cant,but in every speci?c case such a possibility should be studied.Thus,we think that in most,if not all,of the practically important cases one has|ε?1|?1.
It is a well-known fact that the transparent medium is an idealized substance.We assume that a good model of the transparent media is the media in whichε”?|ε?1|,whereε”is the imaginary part of the dielectric function. In the general case the numbers of harmonic n,which may be radiated,lie in the range(?∞,∞).In the vacuum n≥1,always.However,at the condition2χγ2/
√
ε=1+ρ/2is practically equal to the threshold of the Cherenkov radiation.From Eq.(33)it follows that,at the decreasing of the amplitude of the transversal motion(ρ→0),this equation describes the intensity of the Cherenkov radiation.Besides,dI(n=0)/dω=0at2χγ2/
√
v2⊥and hence we can?nd the threshold value of the Lorentz factor for Cherenkov radiation
in the general case
γ2th=1
ε?
v2
⊥
<2χ/
√
γ2(
2χγ2
ε?1?ρ/2).(26)
This result shows that the angle of Cherenkov radiation also depends on theρ-value.From Eq.(17)we see that no limitations on the energy of the emitted photons(for n=0).
Now we consider the case of the usual amorphous media.At high enough frequencies of photons the dielectric function has the following simple form:
ε=1?
?2p
1+ρ/2and the resolved photons energies lie in the intervalω?≤ω≤ω+,where
ω±=
γ2nω0± 1+ρ/2.(29) The threshold value of the Lorentz factor for the harmonic number n is equal to
γth=
?p
n2ω20?ω0
2n. These results are in agreement with those in[17,18](for the1st harmonic)and[32].
It is well known that in usual media the dielectric function is smaller than1at high enough photon energies.Thus, the Cherenkov undulator radiation is possible mainly at the photon energies<～10eV.Besides,there exists the possibility to observe this radiation on the photoe?ect absorption edges[25,26].In this case the energy of emitted photons has a value<～1KeV.
In accordance with quantum electrodynamics[27]the electromagnetic vacuum represents the medium in which the dielectric function may be larger than1.However,for electric?elds which may be obtained in laboratories(<106 gauss)the valueε?1is very small and the particles with Lorentz factors larger than1010can feel this value.In paper [28]the Cherenkov radiation was predicted in silicon single crystals(i.e.the analogue of the quantum undulator)for particles withγ>108.However,our considerations allow us to predict the speci?c radiation of negative harmonics in single crystals.A similar e?ect is also applied to the propagation of high energy charged particles in power laser waves[29,30].
Below we present some examples of calculations of the radiation of relativistic particles for quasiperiodic motion in the medium.These calculations were done with the use of Eq.(21)assuming that the particle motion in the transversal plane is harmonic:v⊥=aω0cosω0t.
Figs.1and2illustrate the in?uence of media on the radiation in the crystal undulator[13,14,15].In the silicon single crystal at photon energies larger than10KeV the dielectric function is smaller than1.The disappearance of the?rst harmonic in such media is shown in Fig.1.Fig.2illustrates the medium in?uence in the case when the?rst harmonic is partially radiated.Notice that these?gures were made only for aim of illustration and do not take into account many peculiarities of the real process(such as the in?uence of the channeling motion,etc.).
Let us consider the particle radiation in the undulator with the dielectric function larger than1.In practice it may be a gas-?lled undulator.Let the energy of particles moving in the undulator satisfy the condition for Cherenkov radiation(see Eq.(26)).Then the connection between the angle of radiation of the n-th harmonic and the angle of the Cherenkov radiation follows from Eq.(18)
θ2(n)=θ2Ch+2nω0
εω
.(31)
From here,we get that the condition of radiation of the n-th harmonic is
n>?θ2Ch
√
2ω0
.(32)
Obviously all the positive n satisfy this condition and negative n satisfy Eq.(26)starting from some number n min.
Let us imagine a medium with constant dielectric function(ε>1)for all photon energies.From our consideration (see Eqs.(25),(26),(31),(32)and the condition for the Cherenkov radiation to take place)it follows that in this medium the positive harmonic is radiated at all photon energies.There is a threshold for negative harmonics in this medium. In this case the radiation of these harmonics takes place at all above-threshold energies,and with the increasing of photon energy the number of radiated harmonics also grows.In particular,the frequencyω0determines only the threshold energy of radiated harmonics.This consideration shows that the character of radiation(at the pointed conditions)is appreciably di?erent than in the usual undulator.
For illustration of this case we carry out the calculation of the propagation of the beam with the Lorentz factor equal to400in the gas-?lled undulator with a period equal to10cm.We also assume the valueχ=10?4at photon energies lower than1eV,andχ=0at energies higher than1eV.This value is several times smaller than in many gases at the atmospheric pressure.The energy range of photons corresponds approximately to visible light.Fig.3 illustrates the spectral intensity of the radiation atρ=0.39.In this case harmonics with the numbers-1,0,1are predominantly radiated.We see that at small energies the radiation of the zeroth harmonic dominates(in accordance with Eq.(24)).The total intensity grows proportionally to the photon energy and hence is equal to the intensity of Cherenkov radiation in any medium,which is characterized by the correspondingε-value.
Fig.4illustrates the behavior of the intensity of radiation,depending on theρ-parameter.One can see that atρ≈62 the intensities of all the negative and zeroth harmonics disappear.The structure in curves at large enoughρre?ects the disappearance of the negative harmonics.The peak atρ≈38corresponds to the harmonic with n=?3.At the
√
?xed Lorentz factor one has a threshold valueρth=4χγ2/
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[11]We,following the authors of Ref.[3,12]of one the?rst publication in this?eld)cannot agree with some statements of the
article[10]which touch upon some historical aspects and assessments of the contribution of di?erent authors to this issue.
[12]V.G.Baryshevsky,(Private communication).
[13]S.Bellucci,S.Bini,V.M.Biryukov,Yu.A.Chesnokov,S.Dabagov,G.Giannini,V.Guidi,Yu.M.Ivanov,V.I.Kotov,V.A.
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276.
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Biryukov,S.Bellucci,Nucl.Instrum.Meth.B230,619(2005).
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Chepegin and Yu.A.Chesnokov,JETP Letters,82,562(2005);A.G.Afonin,V.T.Baranov,S.Bellucci,V.M.Biryukov,
G.I.Britvich,V.N.Chepegin,Yu.A.Chesnokov,C.Balasubramanian,G.Giannini,V.Guidi,Yu.M.Ivanov,V.I.Kotov,
A.Kushnirenko,V.A.Maisheev,C.Malagu,G.Martinelli,A.A.Petrunin,V.A.Pikalov,A.Raco,V.V.Skorobogatov,
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Afonin,V.T.Baranov,S.Baricordi,S.Bellucci,G.I.Britvich,V.N.Chepegin,Yu.A.Chesnokov,C.Balasubramanian,G.
Giannini,V.Guidi,Yu.M.Ivanov,V.I.Kotov,A.Kushnirenko,V.A.Maisheev,C.Malagu,G.Martinelli,https://www.doczj.com/doc/a97012002.html,an,A.A.
Petrunin,V.A.Pikalov,V.V.Skorobogatov,M.Stefancich,V.I.Terekhov,F.Tombolini,U.I.Uggerhoj,”Accelerator Tests of Crystal Undulators”,physics/0412159;S.Bellucci.Mod.Phys.Lett.B19(2005)85.
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VII.FIGURE CAPTIONS
Fig.1Intensity of radiation in a silicon crystal undulator with the period and amplitude equal to0.05cm and100 angstrom,respectively.The energy of the positron beam is10GeV.Thin and thick curves correspond to radiation in vacuum and media,respectively.The parameterρhas the valueρ=6.4.
Fig.2.The same as in Fig.1,but with the amplitude a=55angstrom andρ=1.83.
Fig.3Intensity of radiation in gas-?lled undulator as a function of the photon energy.Curves-1,0,1correspond to radiated harmonics with n=-1,0,1.The thick curve is the total intensity.The dotted curve is the intensity in vacuum enlarged500times(with the values of the other parameters remaining unchanged).
Fig.4Intensity of radiation in gas-?lled undulator as a fuction ofρ-parameter.Curve0corresponds to the zeroth harmonic,curve1(-1)corresponds to the sum of intensity of all the positive(negative)harmonics.The thick curve is the total intensity.The energy of radiated photons is equal to1eV.
Fig.5Radiation of the harmonics in the gas-?lled undulator.The angleθis along the abscissa axis and the intensity of radiation of the n-th harmonic is along the ordinate axis.The numbers above intercepts,showing the intensity,are the numbers of the harmonics.The intensity of the6th and7th harmonics are invisible(due to their small values). The energy of radiated photons is equal to1eV.The angleθfor the0-th harmonic is independent of the photon energy and for other harmonics these angles are changed in accordance with Eq.(31).The parameterρtakes the value ρ=3.8.
FIG.1:
FIG.2:
FIG.3:
FIG.4:
FIG.5:
词汇学的基本知识 词汇学是研究词语的学问，它是传统语言学（语法、语音、词汇）的一个分支。词汇学的 主要研究的内容是：词的性质、词的构成、词义的本质及发展、词的各种关系（同音、同 义、反义等）。 一、什么是词 词是有意义的能够独立运用的造句的最小单位，它具有固定的语音形式。汉语词的划分有一 定的困难，因为在书写时词和词之间是不分开的。就“独立运用”而言，许多虚词和量词是 不能独立运用的。于是增加了一条补充，一句话中把能独立运用的词划分出去，剩写的也是词。如：“我把这本书包了个书皮。”这个句子中的“本”“个”和“把”也是词。汉语中词 和短语的界限也不很清楚。一般可以用扩展插入法来区分。能插入的是短语，不能插入的是 词（意义不能变）。比如：钢笔——钢的笔、白菜——白的菜、白布——白的布、吃饭——吃 了饭、鸡蛋——鸡的蛋、睡觉——睡不睡觉。“钢笔”不能插入词，“白菜”插入后意思变了，它们肯定是词。“白布”可以插入且意思不变，可以做为短语。“吃饭”可以插入，“鸡蛋”可 以插入，但“鸡蛋”的频度很高，可以把它做为词。睡觉可以插入，但两个语素的组合是固 定的，把这类词做为离合词（理发、洗澡、打仗等）。 一个语素（有意义的汉字）能独立运用就是词。（米、吃、红、个、从） 两个语素组合后，意义不是它们的简单相加，就是词。（钢笔、金鱼、） 两个语素组合后，不能扩展插入词，就是词。（钢笔，白菜） 两个语素组合后，虽能扩展插入词，但它们是不能用别的语素替换的，则是一种特殊的词 ——离合词。 两个语素组合后，虽能扩展插入词，但它们的使用频度很高，且大家约定俗成认为它是词。（“鸡蛋”是词、“鹰蛋”就有人认为是短语）。 综上所述，汉语的词与短语之间的界限是有模糊地带的。 人们对客观世界的认识形成了概念，词是反映概念的，但它们之间的关系不是一一对应的。 比如，“月亮”、“月球”对应的是一个概念，“人民”这个词可以对应不同的概念。 二、现代汉语词汇的构成 词汇由词和固定的短语——熟语、谚语等构成。 词可以从不同的角度分类： 1.语法分类——实词、虚词（词类） 2.结构分类——单纯词、合成词 3.音节分类——单音节词、多音节词 4.常用——常用词汇（基本词汇）、一般词汇 5.口语词汇——书面词汇 6.普通话词汇——方言词汇 7.汉语词汇——外来语词汇 8.古词语——新词语 熟语可以包括成语、谚语、歇后语等。成语表意凝炼、形象，在书面语中广泛运用。它来源 于古代的典故，有的选取原句中最能概括原句意思的成分（乘风破浪——愿乘长风，破万里浪），有的用四个字概括寓言、故事等（刻舟求剑、狐假虎威），有的增加个别字（短兵相接——车错毂兮短兵接）。成语的意思有的是语素义的简单相加（汗流浃背、无稽之谈、自圆其说）；多数成语的意思不是语素义的相加，有的意思是约定俗成的（高山流水——表示知己知音），有的是取字面的比喻义（水落石出——比喻真相毕露了）。
软件公司市场部的工作职责 进入IT行业，更准确的说是进入ERP行业，很真切的感受到行业的不同对市场部岗位设置要求的不同。 传统营销理论谈的是：4P，price价格、product产品、place渠道、promotion促销，市场部的主要工作职责可能也是围绕这些方面。但ERP软件公司很不同，比如：product：一套软件产品的生命周期通常在3-5年，软件的开发、需求确定等往往由技术部门主导，虽然有的大公司设有产品经理（理论上说也属于市场范畴），但大部分中小软件企业的市场部不包括产品开发该职能。Price：目前随着ERP市场竞争的激烈，随着客户成熟度的提高，目前一套ERP产品的售价往往取决与客户的议价能力、预算范围及竞争压力。在此方面，市场部起到的作用也不是非常大。Place：如果软件厂商没有设置代理商，市场部也没有用武之地了。Promotion：ERP产品面对的客户都是企业组织，属于组织购买行为，不是普通的广告、促销就能打动的了的。 那么软件公司是不是就没有必要设置市场部了？ 当然不是，而是在ERP行业，市场部的职责不同于其他行业。 对ERP等软件公司而言，最重要的是品牌建设及销售促进。软件公司的市场部，更应该以4C理论为指导：customer needs，cost，communication，convience。 细化一下，软件公司市场部的主要工作职责可以分为一下几类： 1、市场调研：关注行业动态，了解目标市场发展趋势及技术趋势等。 2、竞争者分析：对竞争对手历史、技术实力、成功失败案例、商务政策等要有一个基本的认识和了解。分为几个层次：知道竞争对手是谁；知道竞争对手做了什么；知道竞争对手未来会做什么；影响竞争对手策略。 3、品牌建设与推广。包括媒体宣传、网络营销、参加行业展会论坛等。 4、市场活动的策划与组织。 5、公关关系的维护，包括政府、协会、媒体等。 6、合作伙伴关系维护。 7、客户关系维护。软件公司更多的是关系影响，塑造标杆客户等非常重要。
现代汉语词汇学学习心得 本篇文章分为二个部分，第一部分主要来谈谈学习现代汉语词汇学课程的感想和收获，第二部分阐述我在学习了这门课程后对于如何进行对外汉语词汇教学的一些思考。 一．学习现代汉语词汇学课程的感想和收获 对于现代汉语词汇我们不是第一次接触了，早在大一的现代汉语课上就已经有所涉及。但那都是很笼统的讲到，并没有做具体的分析研究,到了大三下学期才单独开设了现代汉语词汇学这门课程。在上这门课程前，就听学姐学长讲过词汇学很难，在学了这门课之后深有体会。记得在一开始的练习中就碰到了困难，如分析哪些是词自己就有点糊涂了，原因是自己还没有弄清楚词的具体该概念，即确定词的的一般方法，尤其是在扩展法上会出现问题。但后来经过讨论，老师讲解，自己终于有所领悟。虽然在学习的当中会碰到很多难题，但通过一学期的学习，自己也有很多收获。 首先来谈谈教材，我们词汇学选符准青的《现代汉语词汇》增订本就是一本很好的教材。它的编订很合理，内容很详细，每章后都附有练习，有助于我们巩固我们所学的知识。除了解决词汇学中的一般问题，另外还提出了很多疑难问题让我们注意，这是其他教材很难做到的。例如第一章节疑难问题就提出具有争议的问题，如何确定述补结构（吃饱打倒）等是不是词的问题，这些疑难问题对于我们真正把握词的概念，拓展我们的思维有很大帮助。 其次，我也非常庆幸遇到一位优秀的老师来教授我们这么课程。老师
有着扎实的专业基础知识和丰富的对外汉语教学经验，所以知道怎样使我们很好的接受那些词汇学知识，更重要的是我们能够将学到的知识理论应用于实际。在学习的过程，老师并没有像填鸭子似地把知识抛给我们，而是时不时的给我们提一个问题，让我们去思考，虽然最后我们的答案并不尽人意，但至少给了我们一个锻炼思考能力及分析问题的机会。在学习过程中老师一直强调我们不要读死书，要学会思考，这本书固然有它的优点，也存在一定的缺点，我们要取其精华，剔其糟粕。例如在学习第七章词汇划分问题上，老师就告诉我们书上的词汇划分不科学，对于基本词汇和一般词汇的定义模糊，但在基本词汇的特点上有可取之处，基本词汇具有普遍性，稳固性和构成新词的基础，这一点很可取。 再者，学习这门课程后我认识到词汇学的重要性，词汇学最为一门单独的专业课程开设是很有必要的。现代汉语词汇是不断丰富发展变化着的。社会生活的发展，包括新事物的出现，旧事物消灭，阶级斗争的发展；人的思想意识的发展；语言内部各个因素的相互作用等等。现代汉语词汇是历代积累传承下来的大量词语和和不断产生的大量词语组合起来的整体。学习现代汉语词汇有着十分重要的意义，它让我们意识到词汇的重要性，提高我们的表达能力、语言能力，而且有助于语文教学，词汇教学在语文教学中占有重要位置。要引导学习者掌握丰富的词语，正确理解词语的意义，正确运用词语，就要利用现代汉语词汇学所学的各种知识。因此，一定要通过自身的努力学好掌握好这门学问。 最后，通过这门课程的学习，我对怎样才能学好现代汉语词汇学有了一些体会。虽然这门课程即将结束，但学问是无穷无尽的，这门课程只是为我们打开了学习词汇学的一个窗口，在平时我们还应当坚持课后自主学习，因此掌握一些学习词汇学的方法尤为重要。
岗位：项目经理 主要职责： 1、计划： a)项目范围、项目质量、项目时间、项目成本的确认。 b)项目过程/活动的标准化、规范化。 c)根据项目范围、质量、时间与成本的综合因素的考虑，进行项目的总体规划与阶段计划。 d)各项计划得到上级领导、客户方及项目组成员认可。 2、组织： a)组织项目所需的各项资源。 b)设置项目组中的各种角色，并分配好各角色的责任与权限。 c)定制项目组内外的沟通计划。（必要时可按配置管理要求写项目策划目录中的《项目沟通计划》） d)安排组内需求分析师、客户联系人等角色与客户的沟通与交流。 e)处理项目组与其它项目干系人之间的关系。 f)处理项目组内各角色之间的关系、处理项目组内各成员之间的关系。 g)安排客户培训工作。 3、领导： a)保证项目组目标明确且理解一致。 b)创建项目组的开发环境及氛围，在项目范围内保证项目组成员不受项目其它方面的影响。 c)提升项目组士气，加强项目组凝聚力。 d)合理安排项目组各成员的工作，使各成员工作都能达到一定的饱满度。 e)制定项目组需要的招聘或培训人员的计划。 f)定期组织项目组成员进行相关技术培训以及与项目相关的行业培训等。 g)及时发现项目组中出现的问题。 h)及时处理项目组中出现的问题。 4、控制 a)保证项目在预算成本范围内按规定的质量和进度达到项目目标。 b)在项目生命周期的各个阶段，跟踪、检查项目组成员的工作质量； c)定期向领导汇报项目工作进度以及项目开发过程中的难题。 d)对项目进行配置管理与规划。 e)控制项目组各成员的工作进度，即时了解项目组成员的工作情况，并能快速的解决项目组成员所碰到的难题。 f)不定期组织项目组成员进行项目以外的短期活动，以培养团队精神。 结语： 项目经理是在整个项目开发过程中项目组内对所有非技术性重要事情做出最终决定的人。 岗位：系统架构师（技术总监） 主要功能及职责：
总，再加上个例子就可以拿满分了。区分两个词的区别，主要还是指明其各自的定义。 第一章 1. Word —— A word is a minimal free form of a language that has a given sound and meaning and syntactic function. 2. There is no logical relationship between sound and meaning as the symbolic connection between them is arbitrary and conventional. E.g. ―woman‖ means ’Frau’ in German，’Femme’ in French and ’Funv ’in Chinese. On the other hand，the same sound /rait/ can mean right，rite and write，though denoting different things，yet have the same sound. 3. The difference between sound and form result from 4 major factors. （At least 80%of the English words fit consistent spelling patterns） a）. the internal reason is English alphabet does not have a separate letter to represent each sound in the language. b）. Pronunciation has changed more rapidly than spelling c）. Influence of the work of scribes/printing freezes the spelling of words in 1500 d）. Borrowing of foreign language 4. Vocabulary —— Vocabulary is most commonly used to refer to the sum total of all the words of a language. It can also refer to all the words of a given dialect，a given book，a given subject and all the words possessed by an individual person as well as all the words current in a particular period of time in history. The general estimate of the present day English vocabulary is over 1 million words. 5.Classification of Words—by use frequency，by notion，by origin 1）. Basic word stock – the foundation of the vocabulary. 1. all national character （most important）– natural phenomena most common things and phenomena of the human body and relations world around us names of plants and animals action，size，domain，state numerals，pronouns，prep. ，conj. 2. stability – they donate the commonest thing necessary to life，they are like to remain unchanged. Only relative，some are undergoing some changes. But the change is slow. e.g. arrow，bow，chariot，knight – past electricity，machine，car，plane —— now 3. productivity – they are mostly root words or monosyllabic words，they can form new words with other roots and affixes. e.g. foot – football，footage，footpath，footer 4. polysemy – often possess more than one meaning. Become polysemous. e.g. take to move or carry from one place to another to remove 5. collocability – quite a number of set expressions，idiomatic usages，proverbial saying and others e.g. heart – a change of heart， a heart of gold Non-basic vocabulary —— 1. terminology – technical terms photoscanning，hepatitis，indigestion，penicillin，algebra，trigonometry，calculus 2. jargon – specialized vocabulary in certain professions. Bottom line，ballpark figures，bargaining chips，hold him back，hold him in，paranoid 3. slang —— substandard words often used in informal occasions dough and bread，grass and pot，beaver，smoky，bear，catch，holler，Roger，X-rays， Certain words are labeled slang because of their usage. 4. argot – words used by sub-cultured groups can-opener，dip，persuader cant，jargon ，argot are associated with，or most available to，specific groups of the population. 5. dialectal words – only by speakers of the dialect beauty，chook，cocky，station，auld，build，coo，hame，lough，bog 6. archaisms – words no longer in common use or restricted in use. In older poems，legal document and religious writing or speech. 7. neologism – newly created words with new meaning e.g. microelectronics，futurology，AIDS，internet，E-mail old meaning acquired new meaning e.g. mouse，monitor 2）. Content word （notional word）– denote clear notions. Functional word （empty word，form word）– do not have notions of their own，express the relation between notions，words and sentences. a. Content words constitute the main body of the English vocabulary are numerous. Functional words are in a small number.
Types of meaning Types of lexical changes 1.Elevation:词义升格 Definition: words rise from humble beginnings to positions of importance Some words early in their history signify something quite low or humble, but change as time goes by to designate something agreeable or pleasant. For example: nice: ignorant---foolish---delightful, pleasant Marshal: a keeper of horses---a high ranking army officer So elevation refers that the meaning of word changes from the neutral/negative to positive. 2.Old English:It refers to the English starting from 450 to 1100 AD. The old English is made up of different sources of languages spoken then –that of Anglo-Saxons, that of Celts, and that of Jutes, with a lot of Latin elements used for common peopl e’s life. 3.Bound morpheme: It is the smallest unit of grammar, a unit which cannot occur as separate words. They have no independent semantic meaning; instead, they have: Attached meaning E.g. un-kind, hope-ful Grammatical meaning E.g. cat-s, slow-ly, walk-ing, call-ed For an exact example, in the word “careful”, care is free morpheme, “-ful” is a bound morpheme. 4.Hyponymy: Hyponymy deals with the relationship of semantic inclusion, or to say, the relationship between general lexical items and specific lexical items. That is to say, when X is a kind of Y, the lower term X is the“hyponym”, and the upper term Y is the “superordinate”. For example, “fiction”is the superordinate of “novel”, “novelette”and “short story”, which are the hyponyms of “fiction”. Knowing the semantic features of the hyponyms and their superordinates can help us achieve vividness, exactness, and concreteness in expression.
Language Language is a system of symbol based on physiology, psychology, and physics. It’s a special social action and a carrier of information used for human communication in a society. The relationship between Language, Society, and Thought: 1. any language reflects the culture of the society in a particular period. Therefore language is the mirror reflecting the culture of a society. 2. Language is a product of society. Language is inseparable from human society. 3. Language is used as a means of communication in a society. Outside society there is no language. 4. Society depends upon language for its existence. For example, there are many words connected with carriage. Buggy, a light one-horse carriage with two wheels. Coach, a large closed four-wheel horse-drawn carriage. 5. moreover, man’s thought is indispensable to language just as language is indispensable from society. We know that language is used to express man’s thought. The process of thinking is closely connected with language. That is to say, without thinking, there would be no human language. 6. language serves society as a means of intercourse between people. Linguistics is the scientific study of language. The scope of linguistics include phonology, syntax, semantics, phonetics, philology, lexicology, stylistics, general linguistics, descriptive linguistics…… Lexicology is a branch of linguistics concerned with the study of the vocabulary of a given language. It deals with words, their origin, development, history, structure, meaning, and application. Aim of English Lexicology is to give a systematic description of the English vocabulary. It offers students an insight into the origin and development of the English vocabulary. The significance of English Lexicology: help the learners to enlarge their vocabulary and improve their ability to analyze and use the words. Two approaches to the study of English Lexicology: synchronic and diachronic. Synchronic means describing a language as it exists at one period of time. Diachronic means concerned with the historical development of a language. For example: January, February, march, synchronically, they are the words of the months of one year. Diachronically, they are all borrowed words. Synchronically, we consider words like eventful, talkative as derivatives. Diachronically, they are hybrids, that is, words that are made of two parts, each from a different language. Etymology is the study of the origin and history of words and their meanings. Significance: 1.to provides background information and knowledge about the history, origin and development of the English language. 2. To increase the learner’s enjoyment and real understanding of English words from their changes of forms including their spelling and pronunciation to that of meanings. English is classified as a Teutonic language, that is, a Germanic language. English belongs to the Low West Germanic branch of the Indo-European family. Division of the history of the English language: 1. the period from 450 to 1150 is known as the Old English or Anglo-Saxon period. It’s described as the period of full inflection. 2. The period from 1150 to 1500 is known as the Middle English period, also as the period of leveled inflections. 3. The period from 1500 to the present day is called the Modern English period, also as the period of lost inflection. There are two classes of language in the world: synthetic and analytic. A synthetic language is one which shows the relation of word in a sentence largely by means of inflection. An analytic language is one which indicates the relation of words in a sentence by means of word order, preposition or auxiliary verbs, rather than by inflection. Old English the a synthetic language, while Modern English is an analytic language. Modern English can be divided into two parts: the early Modern English period and the Late Modern English period. Dean Swift was a conservative and he opposed the tendency to shorten words, such as ad
更多资料请访问.(.....) 软件部经理岗位职责 职位名称：软件部经理 所属部门：软件部 直属上级：技术总监 职位概要：负责软件工程项目的具体实施、自有产品及基础技术的开发。 工作内容：管理、组建公司开发团队，参与公司相关政策的制定；拟定和执行本部门年度、月度目标、工作计划及总结；设计、开发、维护、管理软件产品。 一、直接职责 1、拟定本部门年度、月度目标、工作计划及总结； 2、负责本部门的成本控制工作以及本部门员工的绩效考评及监督、管理工作； 3、参与技术业务制定流程及与其他部门的协调工作； 4、领导技术团队并组织实施年度工作计划，完成年度任务目标； 5、负责管理公司的整体核心技术，组织制定和实施重大技术决策和技术方案； 6、负责协调项目开发或实施的各个环节，把握项目的整体进度； 7、指导、审核项目总体技术方案，对各项目结果进行最终质量评估； 8、会同项目经理共同审核项目组内部测试计划，并组织项目组负责软件项目的后期维护工作； 9、针对部门的发展计划，向公司提供部门员工的培训要求，抓好部门员工的专业培训工作； 10、本部门的发展规划，组织审定部门各项技术标准，编制、完善软件开发流程； 11、负责与其他部门之间的沟通与协作，满足和协调公司各相关部门提出的系统更新、新产品等技术需求； 12、关注国内外软件市场的发展动向、最新技术及信息，组织内部技术交流。一三、配合市场部门开展工作，向市场部门提供必要的技术支持。
14、需求调研中，配合项目经理进行需求调研工作，并对生成的需求调研报告进行审核评定。 一五、明确文档编写种类及格式，对项目组需要生成的文档进行质量、数量和时间控制，并组织召开评审会； 16、制度本部门人员短期和长期需求计划，并配合行政部的人员招聘工作； 二、管理职责 1、抓好本部门项目组总结分析报告工作，定期进行项目分析、总结经验、找出存在的问题，提出改进工作的意见和建议，并组织本部门员工学习，为公司领导决策提供专题分析报告或综合分析资料； 2、开展公司的市场经营和客户服务工作，组织开展市场调查、经营分析，掌握竞争对手动态，及时组织竞争方案的制定和实施，确保公司在市场竞争中的主动； 3、组织实施公司机构和人员的调整设置、绩效考核及二级薪酬分配，提出员工的招聘和使用计划，保证公司内部考核、薪酬分配制度的合理完善及人力资源的有效配置，推进公司目标的实现。提供项目的设计方案，协助公司顺利接下项目； 4、参与工程项目的洽谈、制定和审核工作，对公司所签合同有关软件技术合同部分中工期、技术方案、软件合同额等方面提供技术支持； 5、推进公司企业文化建设，掌握员工主要思想动态，倡导队伍的创新和团队精神，提升公司核心竞争能力； 6、规范部门内部管理，提高员工整体技术水平，把握技术发展方向，使得技术发展方向与主流技术合拍； 7、定期组织部门人员培训，组建一个高效、有朝气、技术过硬的开发团队； 三、工作权限 1、对本部职责范围内的工作有指导、协调、监督管理的权力； 2、下属人员的工作态度，工作岗位等考核权、指导权、分配权； 3、所属人员的违纪、违规纠正权及事实处理权或处理申报权； 4、对本部门项目资金使用的额度内审核权； 5、对软件部人员及公司其他相关人员的技术培训提出指导建议权； 四、管辖范围 软件部所工作及总经理授权范畴。 五、工作标准（或要求） 1、严格遵守公司的各项管理制度，认真履行工作职责，行使公司给予的管理权力，软件部统一对外出口为软件部经理； 2、有效、合理的部署全部门的工作安排； 3、及时掌握客户的需求，针对项目方案做出分析； 4、对软件的整体设计以及调研进行审核及补救； 5、调动部门员工的工作热情，使部门形成良好风气； 6、处理部门突发事件，组织人员及时处置； 六、入职要求 1、计算机及其相关专业，大本以上学历。 2、4年以上软件开发经验及2年研发团队管理经验，有独立带领技术团队开发软件产品的成功案例； 3、精通各类型数据库，并能熟练编写数据库存储过程，触发器，熟悉、模式的项目开发； 4、有制造业项目经验，如仓库管理、车间管理、等；
lexicology 题型： 1.填空（30*1=30） 2.解释（10*1=10） 3.主观题（2*10=20） 4.分析词汇学现象（10） 5.翻译（15*2=30） 考点： Chapter 2 Language proper 1.Genetic classification p15: English belongs to the Low West Germanic branch of the Indo-European family. 2.Structural classification: synthetic language & analytic language p22 A synthetic language is one which shows the relation of words in a sentence largely by means of inflections(变音，转调). An analytic language is one which indicates the relation of words in a sentence by means of word order, prepositions or auxiliary verbs, rather than by inflections. Old English (OE 450-1100)synthetic language The history of English begins with the conquest and settlement of what is now England by the Angles, Saxons and the Jutes from about 450 AD. Characteristics of Old English: 1)They had complex inflectional systems for nouns, pronouns, articles, verbs, and adverbs. 2)They had great flexibility in sentence word order made possible by the extensive sets of inflections. Middle English (ME 1100-1500) The transitional period from Old English to Modern English is know as Middle English (ME 1100-1500), which is characterized by the strong influence of French following the Norman Conquest in 1066. Middle English developed rapidly toward becoming an analytic language. Modern English analytic language The English language from 1500 to the present is called Modern English. Characteristics of Modern English 1)Great Vowel Shift ※ 2)Inflections continued to disappear, making Modern English an analytic language. 3)The word order of English sentences became more and more firmly fixed.
《词汇学》名词解释总汇 1.Conversion（转换）is a word-formation whereby a word of a certain word-class is shifted into a word of another without the addition of an affix. It is also called zero derivation. 2.Neologisms（新词用法）are newly coined words or words that are given new meaning to fit new situation because of social, economic, political, cultural, scientific and technological changes in human society. 3.Lexicology（词汇学）is a branch of linguistics concerned with the study of the vocabulary of a given language. It deals with words, their origin, development, structure, formation, meaning and usage. 4.the elevation of meaning（词义的升格）refers to the process by which words rise from humble beginnings to positions of importance. 5.Acronyms（首字母拼音词）words formed from the initial letters of words and pronounced as words. They differ from initialisms in that they are pronounced as words rather than as sequences of letters. 6.Hyponymy(上下义关系)deals with the relationship of semantic inclusion. It refers to the relationship which obtains between the genus (general lexical item)and the species(specific lexical items). 7.Analogy（类比）is a process by which words or phrases are created or re-formed according to the existing patterns in the language. 8.Motivation（理据）deals with the connection between name (word-symbol) and its sense (meaning). It is the relationship between the word structure and its meaning. 9.Metaphor（隐喻）is a figure of speech containing an implied comparison. It is a simile without like or as. 10.Antonymy(反义关系)is concerned with semantic opposition. It can be defined as words which are opposite in meaning. 11.Suffix（后缀）: an affix attached to the end of a base (root or stem) 12. synecdoche（提喻）means using a part for a whole, an individual for a class, a material for a thing, or vice versa, the whole for a part. 13. prefix（前缀）: an affix attached to the beginning of a base (root or stem) 14. initialism（首字母连写词）: a type of shortening, using the first letters of words to form a proper name, a technical term, or a phrase; it is pronounced letter by letter. 15.morpheme(词素): the smallest meaningful linguistic unit of language, not dividable or analyzable into smaller forms. 16.the degradation of meaning（词义的降格）: is the opposite of semantic elevation. It is a process whereby words of good origin fall into ill reputation or non-affective words come to be used in derogatory sense. 17.Derivational affixes (派生词缀)Affixes added to other morphemes to create new words. They can be further divided into prefixes and suffixes。 18. back-formation（逆成法）: is a process of word-formation by which a word is created by the deletion of a supposed suffix. It is also known as a reverse derivation. 19. derivation（派生）: the process by which noninfectional affixes are added to roots to form words. 20. compounding（复合）: the process of joining together two linguistic forms which can function independently.