为抑制两高一资中国出口焦炭出口关税上调至40%
v6系列轻量级平台公式函数使用说明
LFW公式函数使用说明张晓燕本文档主要是对NC6系列中公式的基本使用进行简要说明，给出公式可以支持的参数类型以及对应的返回值类型结果等信息，并对公式函数中的一些特殊情况加以说明。
在类型返回值表中没有提及的情况均视为非法参数条件，会抛出异常。
本文档中由于书写匆忙，若有错误之处，欢迎批评指正。
公式的设置位置系统管理 > 客户化配置 > 模板管理 > 表单模板节点下，选择模板，点击设计。
打开如下界面：选中某个字段，可以设置字段的公式。
包括三种类型的公式：校验公式：点击保存逻辑时调用的公式。
编辑公式：设置编辑公式的字段值改变后调用的公式。
加载公式：加载页面数据时调用的公式。
LFW公式函数使用说明 (1)张晓燕 (1)1. 常用编辑公式 (7)● 1.1 iif(condition, result1, result2) (7)● 1.2 getColValue(tablename,fieldname,pkfield,pkvalue) (8)● 1.3getColValue2(tablename,fieldname,pkfield1,pkvalue1,pkfield2,pkvalue2) (8)● 1.4 isEmpty(str) (9)● 1.5 add(num1,num2) (9)● 1.6 zeroifnull(var) (10)● 1.7 compareDate(date1, date2, field) (10)● 1.8 date() (11)● 1.9 dateAdd(date1, num, fieldchar) (11)2. 常用校验公式 (12)● 2.1 错误提示 (12)● 2.2 消息提示 (12)● 2.3 确认提示 (12)3. 轻量级平台特有公式 (12)● 3.1.计算合计行 (12)● 3.2.禁用某个控件 (12)● 3.3.启用某个控件 (13)● 3.4.显示某个控件 (13)● 3.5.隐藏某个控件 (13)4字符串函数 (14)● 4.1 charat(string,index) (14)● 4.2 endswith(string, end) (14)● 4.3 equalsIgnoreCase(string1, string2) (15)● 4.4indexOf(st1, st2) (15)● 4.5 isEmpty(str) (16)● 4.6 lastIndexOf(st1, st2) (16)● 4.7 left(st, index) (16)● 4.8 leftStr(st,len,defaultStr) (17)● 4.9 length(st) (17)● 4.10 mid(String st, int start, int end) (18)● 4.11 right(String st, int index) (18)● 4.12 rightStr(st,len,defaultStr) (19)● 4.13 startsWith(String st, String start) (19)● 4.14 toLowerCase(String st) (20)● 4.15 toString(obj) (20)● 4.16 toUpperCase(String st) (20)● 4.17 trimZero(value, [decimal]) (21)5.数学函数 (22)● 5.1 abs(num) (22)● 5.2 acos(x) (22)● 5.3 add(num1,num2) (23)● 5.4 asin(x) (23)● 5.5 atan(x) (23)● 5.6 cos(x) (24)● 5.7 div(num1,num2) (24)● 5.8 exp(x) (25)● 5.9 int(x) (25)● 5.10 ln(x) (26)● 5.11 log(x) (26)● 5.12 max(x, y) (26)● 5.13 min(x, y) (27)● 5.14 mul(num1,num2) (27)● 5.15 round(double num, int index) (28)● 5.16 sgn(num) (28)● 5.17 sin(x) (29)● 5.18 sqrt(x) (29)● 5.19 sub(num1,num2) (29)● 5.20 tan(x) (30)● 5.21 toNumber(String st) (30)● 5.22 zeroifnull(var) (31)● 5.23 acosh(param) (31)● 5.24 angle(x,y) (32)● 5.25 asinh(param) (32)● 5.26 atanh(param) (32)● 5.27 cosh(param) (33)● 5.28 mod(x, y) (33)● 5.29 rand() (33)● 5.30 sinh(param) (34)● 5.31 sum(x,y) (34)● 5.32 tanh(param) (34)6. 数据库函数 (35)● 6.1 ass(freevalueID,checktype) (35)● 6.2 cvn(tablename,fieldname,pkfield,pkvalue) (35)● 6.3 cvs(tablename,fieldname,pkfield,pkvalue) (36)● 6.4 getColNmv(tablename,fieldname,pkfield,pkvalue) (36)● 6.5 getColNmv2(tablename,fieldname,pkfield1,pkvalue1, pkfield2,pkvalue2) (36)● 6.6 GetColsValue("tablename","fieldname1","fieldname2 ","pkfield",pkvalue) (37)● 6.7 getColValue(tablename,fieldname,pkfield,pkvalue) (37)● 6.8getColValue2(tablename,fieldname,pkfield1,pkvalue1,pkfield2,pkvalue2) (38)● 6.9getColValueMore(tablename,selectfield,field1,value1,field2,value2....) (38)● 6.10getColValueMoreWithCond(tablename,selectfield,field1,value1,field2,value2...,whereCondition) (39)● 6.11getMLCValue(tablename,fieldname,pkfield,pkvalue) (39)7. 财务函数 (39)●7.1 getChineseCurrency(Object) (39)●7.2 getEnglishCurrency(mark,number) (40)●7.3 setThMark(num) (40)●7.4 toChinese(Object number,int flag1,int flag2) (41)8. 日期类型 (41)●8.1 compareDate(date1, date2, field) (41)●8.2 date() (42)●8.3 dateAdd(date1, num, fieldchar) (42)●8.4 dateFormat(date, pattern) (43)●8.5 datetime() (43)●8.6 day () (44)●8.7 dayOf(date) (44)●8.8 month () (45)●8.9 monthOf(date) (45)●8.10 time() (45)●8.11 toDate(str) (46)●8.12 toDateTime(str) (46)●8.13 toTime(str) (46)●8.14 year () (47)●8.15 yearOf(date) (47)●8.16 dayWeek() (48)●8.15 dayWeek Of(date) (48)9. 基本类型 (48)●9.1 iif(condition, result1, result2) (48)●9.2 比较操作（<,>,<=,>=,!=,=） (49)●9.3 逻辑操作（&&,||,!） (50)●9.4 +操作 (50)●9.5 -操作 (51)●9.6 *操作 (52)●9.7 /操作 (52)●9.8 ^操作 (53)●9.9 %操作 (54)10. 关于公式解析的返回值 (54)1. 常用编辑公式1.1 iif(condition, result1, result2)公式含义简单的if语句，当condition为true时返回result1；当condition为false时返回result2 对应类：nc.vo.pub.formulaset.function.If类型返回值表例子如下：编辑公式举例：defitem9->iif(defitem2!=null&&defitem1!=null,comparedate(defitem2,defitem1,"D"),defitem9); 详解：（1）comparedate(defitem2,defitem1,"D"), defitem2与defitem1都是日期型字段，返回defitem2与defitem1之间天数的差值。
2019年6月A级真题及答案解析
art I I..J i st eni11g C．01n p r c l1e11s10[20 minut e s] Directions: This part is to test your lis砌ing ability. It consfats of 4 sections.Section 1-\Directions: T h is section is to test you1书ability to understand s加rt dialogues. The re are 5 recorded dialogues in it. After each di啦gue,t加re is a recorded question. Both the dialogues·andquestions wil l be spok勿i only once. When you hear a question, you s加uld decide on thecon·ect answ研介01n t加4clwices marked AJ, BJ, CJ and DJ given in your test p a per.Then you s加uld mark the corresponding letter on the Answer Sheet with a single linethrough the center.Example: You will he吓You而U read: A) New York City. CJ An air trip.BJ An evening party. DJ The man's job.肝om t加dialogue we learn that the man is to take a flight to New York. Therefore, C) An air trip is the co灯ect answer. You sho讥d mark CJ on the Answer Sheet with a single line through the cen阮．Now the test will begin.1.A) Prepare the docurnen区B)Book a room for the meeting.2.A) He is going to a party.B)He is making a plan.3.A) The job is interesting.B)The enviromnent is friendly.4.A) The labour cost has risen.B)The income tax has gone up.5.A) Lowering the product price.B)Conducting a market sUIVey.Section B[A][B]伺[D]C)沁k all the managers to attend the meeting.D)Make several copies of the meeting agendaC)He likes to go to the cinema.D)He can't attend the lecture.C)The salary is attractive.D)The colleagues are nice.C)The management cost is on the rise.D)The raw material is in short SUJ:>ply.C)Making a promotion plan.D)Improving the product design.Directions: This section is to test your ability to understand short conversations. There are 2 recorded conversations in it. After each conversation, there are some recorded questions. Both theconversations and questions will be spoken two times: When you hear a question, youshould decide on加correct answer from the 4 choices marked AJ, BJ, CJ and DJ given inyour比st paper. Then you should mark the corresponding letter on the Answer Sheet witha single line through the center. Now listen to the conversations.C o n ver s ation 16.A) He is away on business.B)He is having a meeting.7.A) His flight has been cancelled.B)He has to meet his lawyer.C)He is visiting a client.D)He is on sick leave.C)He was iltjtrred in an accident.D)He is suffering from a fever.8.A) HoldiJ.1g a telephone meetiI1g instead.B)Having it at the s扣ne time next Monday.C m we r sa t io n 29.A) Book a taxi.B)Reser v e a room.10.A) I廿s p邸spmt number.B)His friend's ad由ess.S e ctio C)AE,ldng their assistants to attend it.D)Putting it off until next month.C)Order breal<fast for him.D)Keep things for his friend.C)His room number and email address.D)His friend's name and phone number.Directions: In this section you will hear a recorded short passage. The passage is printed in the比st paper, but with some words or phrases missing. The passage will be re呱two times. Youare requi1攻ed to put the missing words or phrases on the Answer Sheet in order of thenumbered blanks according to what you hear. Now the passage will begin.We are now about to close th�marketing conference. We owe thanks to every member of staff who made the conference a 11 . We would like to thank all of the speakers who have made 12 and impressive speeches. Our thanks also go to every one of you for your contriputions and your appreciation. The energy and the enthusiasm surrounding this conference have been 13 . And now we'll go back··t o our business and put'those 14 into action. It's time to get back to start working on the ne}..1: phase. All customers are out there waiting for us to 15 .Section DD irections: This section is to test your ability to comprehend short passages. You will hear a recordedpassage. After that you will加ar five questions. Both the passage and the questions will beread two _times. When you胧ar a question, you should complete t加answer to it with aword or a short phrase (in no more than 3 words). The questions and incomplete answersare printed in your test paper. You should write your answers on the Answer Sheet correspondingly. Now listen to t如passage.16.,¥hat should you think carefully about before renting a car?The you need.17.How can you get a best deal and save money when renting a car?B y offered by different cru·rental companies.18.V.'hy are you advised to have the car rental company's phone number?In case you need to19.W血should you remember to do if you are returning the car to an airpo兀？Remember to to check in to yo田flight.20.Why should you fill the gas ta nk before rett1rning the car?To save you extra fuel andPart II S tructure 日0minut e s] Direct ions: Tliis part is to test your ability to constr uct gramm atic咄y correc t senten ces. It con s is ts of2 sectio ns.Sect i o11 ADirecti ons: In this section, tliere are 10 incom plete senten ces. You are requir ed to comple te e a c h_ 9ne by decidin g on the nwst approp忧ate word or words frorrl the 4 choices marked A), BJ, CJ andDJ. T I砌you should 1narlc the correspo nding letter on the Answer Sheet with a single linethrou gh the cente r.21.we are able to under乱tand your career object ives, the more likely we are able to help youachieve them.A)More B)The best C)The better D) Much22.You will not be able to improve your work you are aware of your shortcomings.A)if.. B)unless C) when _ D)since23.The training course to introduce you to the security check at the Airport.A)designs B)be designed C)designed·D)is designed24.other words, if employees feel part of the community, they will care more about it s devel-opment.A)In B)For C)On D)With25.We will provide you识th a training program proposal best !fleets your needs.A)who,,. B)what .C)that D)when26.Nearly every career book advises j ob-seekers to send thank-you letters afterA)interviewed B)being interviewed C)be·interviewed D)to be interviewed27.Before each meeting we will decide on the issue and you will be invited to express寸ewsand suggestions via the website.A)discussed B)to be discussed C)to discuss D)discussing28.The person resume best fits the needs of the employer w诅get a call for an interview.A)whose B)which C)that D)who29.we are living in the big data era, we are able to·collect and analyze as much patient in-formation as possible.A)Even though B)As if C)In that D)Now that30.It has been quite some time since we you at your office in Beijing.A)visit B)visited·C) have visited D)had visited Section BDirections: There are 5 incomplele stat叩ents here. You should fill in each blank with the prop窃扣rm 。
如何确定自己真正的出生时辰
如何确定自己真正的出生时辰命理为什么要用真太阳时，其实很容易想明白。
我是这么想的，古时候大家看太阳定时间，不用北京时间的，而命理本来是古时传下来的东西。
所以我们就要调整回本地时间。
确定真太阳时的资料时辰究竟应该按照什么标准确定呢? 唯一的标准就是太阳相对于地球的视角，即天文学上所谓的真太阳时。
凡定生时，必须按照其出生地点，推算出当地的平太阳时，再根据平太阳时推算出真太阳时为准，不能直接采用北京标准时间。
为方便计，下面列出中国各主要城市之平太阳时与北京时间对照表，供参考。
台北 121度31分 +6分04秒呼和浩特 111度38分 -33分28秒包头 110度00分 -40分00秒海拉尔 119度43分 -1分08秒太原 112度33分 -29分48秒临汾 111度31分 -33分56秒大同 113度13分 -27分08秒长治 113度13分 -27分08秒石家庄 114度26分 -22分16秒唐山 118度09分 -7分24秒秦皇岛 119度37分 -1分32秒承德 117度52分 -8分32秒保定 115度28分 -18分08秒张家口 114度55分 -20分20秒北京 116度28分 -14分08秒沈阳 123度23分 +13分32秒鞍山 123度00分 +12分00秒锦州 123度09分 +12分36秒大连 121度38分 +6分32秒长春 125度18分 +21分12秒吉林 126度36分 +26分24秒哈尔滨 126度38分 +26分32秒牡丹江 129度36分 +38分24秒齐齐哈尔 123度55分 +15分40秒上海 121度26分 +5分44秒南京 118度46分 -4分56秒无锡 120度18分 +1分12秒苏州 120度39分 +2分36秒徐州 117度12分 -11分12秒合肥 117度16分 -10分56秒芜湖 118度20分 -6分40秒安庆 117度02分 -11分52秒济南 117度02分 -11分52秒烟台 121度22分 +5分28秒青岛 120度19分 +1分16秒天津 117度10分 -11分20秒杭州 120度10分 +0分40秒绍兴 120度40分 +2分40秒宁波 121度34分 +6分16秒金华 119度49分 +0分44秒温州 120度38分 +2分32秒南昌 115度53分 -16分28秒九江 115度59分 -16分04秒赣州 114度56分 -20分16秒福州 119度19分 -2分44秒厦门 118度04分 -7分44秒泉州 118度37分 -5分32秒长沙 112度55分 -28分20秒湘潭 112度51分 -28分36秒常德 111度39分 -33分24秒衡阳 112度34分 -29分44秒武汉 114度20分 -22分40秒监利 112度53分 -28分28秒沙市 112度17分 -30分52秒宜昌 111度15分 -35分00秒郑州 113度42分 -25分12秒新乡 113度54分 -24分24秒许昌 113度48分 -24分48秒洛阳 112度26分 -30分16秒开封 114度23分 -22分28秒广州 113度18分 -26分48秒珠海 113度18分 -26分48秒澳门 113度18分 -26分48秒韶关 113度33分 -25分48秒汕头 116度40分 -13分20秒深圳 113度33分 -25分48秒香港 114度10分 -23分20秒海口 110度19分 -38分44秒南宁 108度21分 -46分36秒桂林 110度10分 -39分20秒梧州 111度18分 -34分48秒柳州 109度19分 -42分44秒贵阳 106度43分 -53分08秒遵义 106度53分 -52分28秒成都 101度04分 -75分44秒重庆 106度33分 -53分48秒万县 108度22分 -46分32秒内江 105度03分 -59分48秒泸州 105度27分 -58分12秒昆明 102度42分 -69分12秒西安 108度55分 -44分20秒延安 109度26分 -42分16秒宝鸡 107度09分 -51分24秒兰州 103度50分 -64分40秒酒泉 98度30分 -86分00秒天水 105度33分 -57分48秒银川 106度13分 -55分08秒西宁 101度49分 -72分44秒乌鲁木齐 87度36分 -129分36秒克拉玛依 84度51分 -140分36秒哈密 93度29分 -106分04秒和田 79度55分 -160分20秒拉萨 91度02分 -115分52秒达孜 91度23分 -114分28秒林芝 94度28分 -102分08秒曲水 90度44分 -117分04秒贡嘎 90度58分 -116分08秒林周 91度17分 -114分52秒那曲 92度03分 -111分48秒注：1.各地的平太阳时以北京时间相加减,如北京时间12:00时, 武汉地区的平太阳时为12:=12:00-2242=11:3718，即为11时37分18秒。
non-orthogonalmultipleaccess（noma）for
Non-Orthogonal Multiple Access (NOMA) for Indoor Visible Light CommunicationsRefik Caglar Kizilirmak Corbett Ray Rowell Dept. of Electrical and Electronics EngineeringNazarbayev UniversityAstana, Kazakhstanrefik.kizilirrn a********.kz,*********************.kz Abstract-Providing multiple access support to visible light communication (VLC) systems requires new networking architectures. Non-orthogonal multiple access (NOMA) is a proposed multiple access technique for future cellular systems. In this work, based on a realistic indoor channel conditions, we apply NOMA to indoor VLC channels and demonstrate its superior performance over orthogonal frequency division multiple access (OFDMA).Index Terms-visible light communication, OFDMA, NOMA, successive interference cancellationI. INTRODUCTIONVisible light communications (VLC) has recently received considerable attention as an alternative to wireless access technologies operating in radio frequency bands. VLC uses unlicensed spectrum, avoids the health concerns associated with electromagnetic radiation in the microwave bands, and achieves high data rates [1]. Although most of the recent advances in the field consider point-to-point transmission, networking with multiple access (MA) support for VLC is essential to provide multi-user wireless services such as Internet access in an office environment.Most of the MA techniques in radio and optical engineering can be applied to indoor VLC channels. For instance, well known cellular MA techniques such as time division multiple access (TDMA), frequency division multiple access (FDMA), or code division multiple access (CDMA) together with some optical MA techniques such as wavelength division multiple access (WDMA) and space division multiple access (SDMA) have already been proposed for visible light communications [2].NOMA is fundamentally different than other multiple access schemes which provide orthogonal access to the users eitherin time, frequency, code, or space. In NOMA, each user operates in the same band and at the same time where they are distinguished by their power levels. NOMA uses superposition coding [3][4] at the transmitter such that the successive interference cancellation (SIC) receiver can separate the users bothin the uplink and downlink channels. NOMA was originally proposed as a candidate radio access technology for 5G cellular systems [4]. Although the practical implementation of NOMA in 5G cellular networks is still under discussion, it can be readily employed by VLC systems. First, the SIC receiver978-1-4673-7726-3/15/$31.00 ©20151EEE 98Murat UysalDept. of Electrical and Electronics EngineeringOzyegin UniversityIstanbul, Turkey***********************.trperforms better with fewer users; this is usually the case for VLC, but not for cellular networks. Secondly, superposition coding requires the channel knowledge for each user in order to adjust the power split between them; in VLC, unlike cellular networks, user terminals are usually stable and the channel is deterministic. VLC network characteristics perfectly match with the requirements for a successful NOMA implementation. In this work, we propose the use of NOMA in a VLC downlink channel with a two-user scenario and compare its performance with OFDMA based VLC networks. DC biased optical OFDM (DCO-OFDM) [5] is used for both NOMA and OFDMA as it is most commonly used bipolar-to-unipolar conversion technique in optical OFDM systems. A concurrent study in [6] also discusses application of NOMA to VLC systems. Our work is different from [6] in two major aspects: First, we consider optical OFDM transmission and compare the achievable capacities of NOMA and OFDMA and second, we include the impact of cancellation error in SIC receiver and analyzed for VLC systems with further comparison of NOMA and OFDMA systems.The paper is organized as follows: Section 2 introduces the channel models for two user scenario. Section 3 presents DCO-OFDM based NOMA and OFDMA. Section 4 presents the results of the numerical studies, and finally, Section 5 concludes the paper.II. INDOOR CHANNEL MODELThe room is modeled as an indoor office space with dimensions 5x5x3meters (Fig. 1) where two user equipments (VEs) are sharing the common downlink channel.In order to obtain the channel impulse responses, the methodology described in [7] is followed based on ray tracing simulations using Zemax@ [8]. The reflection coefficients of the walls, ceiling, floor and desk surface are taken as 0.8, 0.8, 0.3 and 0.8, respectively. When the location of the center of the ground is set at (0,0,0), the locations of the light source, VEl and VE2 are respectively chosen as (0,0,3), (0, 0, 0.7) and (1.7, 1.9, 0.7). Fig. 2 presents the obtained channel impulse responses hI (t) and h2(t) for UEI and UE2, respectively. The electrical channel DC gains are then calculated as GI I hI(t)dt -52 dB and GI I hI(t)dt -58 dB respectively for VEl and VE2.h y2.5 m i, .' ............ _-t ........__ , ". G : : •••• 2 :G : •..• : ' : ..... . , . Sm , OFDMA 1 1 UEI UE2 conjugate I ( NOMA1 . 1 conjugate I .... symmetric ----. 1 I � Bandwidth ---- 1 1 Fig. 1. Room with two users sharing the common downlink channel. 4.5 .5 � 2.5 1.5 0.5-6 xlOtime (nsec)(a) � 0.8� 0.60.402 -6 xlOtime (nsec) (b)Fig. 2. Channel impulse responses with respect to 1 watt transmitted optical power for (a) VEl (b) VE2. III. SYSTEM MODELNOMA and conventional OFDMA are illustrated conceptually in Fig. I where in OFDMA, the two users share thedifferent parts of the bandwidth whereas NOMA utilizes allthe band for each user. In this section, we first present NOMA,then discuss OFDMA as a benchmark.A. NOMA with DCO-OFDM Fig. 3 shows the block diagram of DCO-OFDM basedNOMA system in downlink. The NOMA transmitter processesthe information of both users in parallel and obtains OFDMsignals Xl(t) and X 2(t) for VEl and VE2. In DCO-OFDM,the complex symbols s (PSK, QAM etc.) are first assignedto a subcarrier vector. The OFDM time domain signal isthen obtained by IFFT operation. One important constraintin IMIDD optical communication is that the waveform whichmodulates the LEDs should be real-valued and non-negative.It is known that when the complex subcarrier vector X satisfiesthe Hermitian symmetry property, the time signal at the output IFFT becomes real [9]. Hermitian symmetry can be imposedby constructing X as 99where N is the number of subcarriers. As seen in (1), obtaining a real-valued Xl(t) and X 2(t)sacrifices approximately half of the spectral efficiency for each user. The transmitter then applies superposition coding and forms the transmitted waveform as [3][4] where P is the total available power for the transmitted signal and Kn is the power splitting factor which defines the power levels to be allocated to each information signal. In (2), lE[lxl(t)12] and IE[lXl(t)l 2] are normalized to one. It is also possible to apply superposition coding first and then apply IFFT Finally, the DC biased signal x N (t) modulates the luminary which consists of L number of LED chips. The electrical signal at the receiver of VE k , k E 1, 2, can then be written as LI'JPL hk(t)Q9x(t) + nk(t) (3) i=l L I'L hk(t) (t) + Kn )X 2(t)] i=l2015 4th International Workshop on Optical Wireless Communications (I W OW)2010o 10 15 20Rate of user 2 (Mbps)25 30 35Fig. 5. Boundary of rate pairs (Mbps) for NOMA and OFDMA. Perfect interference cancellation is assumed for NOMA.2010o 10 15 20Rate of user 2 (Mbps)25 30 35Fig. 6. Boundary of rate pairs (Mbps) for NOMA and OFDMA. Imperfect interference cancellation is assumed for NOMA.V. CONCLUSIONIn this work, NOMA has been proposed and analyzed for indoor VLC downlink channels. For a realistic indoor channel model with illumination design constraints, the superior performance of NOMA over conventional OFDMA scheme has been demonstrated. Although, the receiver complexity can be seen as a drawback for NOMA, the return is considerable. Future work includes developing power allocation mechanism for higher number of users and building a prototype.ACKNOWLEDGEMENTWe would like to thank Mr. Farshad Miramirkhani for his kind assistance in preparation of Fig. 2 in Section 2.REFERENCES[1] T. Komine, M. Nakagawa,"Fundamental analysis for visible-light communication system using LED lightings", IEEE Trans. on Comsun.Electron.,vol. 50, pp. 100-107, 2004.[2] H. Elgala, R. Mesleh, H. Haas, "Indoor optical wireless communication:potential and state-of-the-art",IEEE Communications Magazine, vol. 49, no: 9, pp. 56-62, 2011.[3] Y. Saito,et. ai, "System level performance evaluation of downlinknonorthogonal multiple access (NOMA)," in Proc. IEEE Symposium on Personal, Indoor and Mobile Radio Communications (PlMRC), Sept.2013.[4] Y. Saito, et, ai, "Non-orthogonal multiple access (NOMA) for future radioaccess," in Proc. IEEE Vehiccular Technology Conference (VTC Spring), pp. 1-5, Sept. 2013.[5] J. Armstrong, "OFDM for optical communications", Journal of LightwaveTech., vo1.27, no.3, pp. 189-204, Feb., 2009.[6] H. Marshoud, V. M. Kapinas, G. K. Karaganniadis, S. Muhadiat,"Non-orthogonal multiple access for visible light communications,"lpdf/1504.oo934.pdf.[7] E. Sarbazi, M. Uysal, M. Abdallah and K.Qaraqe, "Indoor channelmodeling and characterization for visible light communications", 16th International Conference on Transparent Optical Networks (ICTON), July 2014.[8] [9] R. Mesleh, H. Elgala, and H. Haas, "On the performance of differentOFDM based optical wireless communication systems", J. Opt. Commun.Netw., vol. 3, no. 8, pp. 620-628, 2011.[10] J. Grubor, S. Randel, K-D. Langer, and J. W. Walewski, "Broadbandinformation broadcasting using LED-based interior lighting", J. of Lightwave Tech., vol. 26, no. 24, pp. 3883-3892, 2008.[11] J. G. Andrews, and T. H. Meng, "Optimum Power Control for SuccessiveInterference Cancellation With Imperfect Channel Estimation", IEEE Trans. on Wireless Comm., vol. 2, no. 2, pp. 375-383, 2003.[12] D. Tse and P. Vishwanathan, "Multiuser capacity and opportunisticcommunication," Fundamentals of Wireless Communication, 2005. [13] S. A. Colak, R.C. Kizilirmak, M. Uysal, "On the Performance ofDCO-OFDM Visible Light Communication Systems under illumination Constraints", in Proc. Int'1. Con! on Transparent Optical Networks (ICTON), pp.I-4, 2015.[14] Cree XLamp XP-E2 LEDs, datasheet.[15] M Rahaim, A Miravakili, T Borogovac, IDC Little, V Joyner, "Demonstration of a software Defined Visible Light Communication System," in Proc. the 17th Annual International Conference on Mobile Computing and Networking, Mobicom20 11.[16] I. Stefan, H. Burchardt, and H. Haas, "Area spectral efficiency performance comparison between VLC and RF femtocell networks," in Proc.IEEE Inti Con! on Commun. (ICC) , pp. 3825-3829, 2013.101。
今天学校举行了运动会开幕式作文精选6篇
篇1：今天学校举行了运动会开幕式作文今天学校举行了运动会开幕式，哎呀，那场面可真是不一般啊！一大早就看到那操场上一片热闹非凡，彩旗飘飘，锣鼓喧天。
一溜排开的看台上坐满了老师和学生，一个个兴高采烈，脸上洋溢着快乐的笑容。
我还看到有几个老师拿着相机，一个劲儿地按快门，生怕错过了哪个精彩的瞬间。
我带着好奇心走到操场中央，只见校长站在主席台上，胸前挂着红领巾，神采奕奕。
他手持麦克风，大声宣布：“今天，我校运动会开幕式正式开始！”这声音洪亮，整个操场都能听到，让人精神一振。
接下来是入场式，各个班级排着整齐的队伍，精神抖擞地走向操场。
同学们身穿校服，有的戴着鲜艳的领巾，有的手持鲜花，有的挥舞着小旗。
我注意到，有些班级还别出心裁地制作了花环，让人眼前一亮。
最让我印象深刻的是，有几个班级的队形非常有创意，他们排成了一朵朵花，一匹匹马的形状，还有的排成了“迎奥运”的字样。
这些创意让我不禁为他们的聪明才智点赞。
入场式结束后，校长发表了热情洋溢的讲话，他强调了运动的重要性，鼓励同学们积极参加体育锻炼，展现我校学生的精神风貌。
讲话完毕，他还宣布了本次运动会的比赛项目。
接下来是运动员代表和裁判员代表宣誓，他们的声音铿锵有力，让人感受到了他们的决心和担当。
宣誓结束后，主持人宣布运动会正式开始。
这时，我看到有几个同学兴奋地跳了起来，还有的挥舞着双手，大声喊道：“加油，加油！”整个操场都沸腾了。
运动会开幕式虽然结束了，但那热闹的气氛却一直弥漫在空气中。
我觉得这次运动会一定会举办得非常成功，同学们都会在比赛中展现出最好的自己。
毕竟，这是我们展示青春风采的舞台，是我们挥洒汗水、追逐梦想的地方。
篇2：今天学校举行了运动会开幕式作文今天学校举行了运动会开幕式，那场面，哎呀，真是热闹非凡，让我这个平时不爱运动的人也忍不住跃跃欲试。
话说那天早晨，阳光明媚，清风拂面，一看就是好天气。
我走进学校，嘿，全校师生都聚在学校广场上，一个个精神抖擞，满脸期待。
数字的读法
美元的符号$是怎么来的大家都知道，$ 表示美元。
那么它是怎样来的呢？一种说法是，它是P S 叠合写法的演变。
PS是18至19世纪期间美国的一种圆形硬币比索（Pesos）的缩写，这种硬币在1974年美国正式建立造币厂以前一直在全国通用。
后来美国政府认可了$这个符号作为新货币的一个单位，即一美元。
在书写时，$要摆在数字前面。
如1美元应写成$1，50美元写成$50。
而这种写法的背后还有一个小故事。
It is only appropriate that an Irish immigrant to the United States be the one credited with originating the dollar sign. Oliver Pollock sailed the high seas at the age of twenty-three, and settled in Carlisle, Pennsylvania. This young entrepreneur rapidly established himself as a wealthy and influential West Indies trader.Pollock moved his operation to Louisiana, where he amassed even more wealth as a trader, and as a plantation owner. His success enabled him to provide supplies to the Patriots’ cause in the Revolutionary War, and to maintain close contact a nd a degree of influence with Congress. Pollock’s success allowed him easily to purchase military supplies to support “the cause,” as the Spanish Empire had an outpost in New Orleans, Louisiana. In his dealings with the Spaniards, Pollock used their currency, the peso.In true Spanish tradition, Pollock used an abbreviation for pesos, yet his penmanship made the abbreviation appear to be the transposition of the letters “p” and “s.”Prior to 1775, the fledgling nations monetary system was in disarray, and needed to be revamped. By 1775, Congress decided to rectify the situation by backing all of its legal tender with the most commonly circulated coins that were, coincidentally, Spanish coins minted in the New World. Americans then began trading with “Spanish milled dollars,” later termed “dollars,” as Americans shed the “pounds” that were the vestiges of British rule.Congressman Robert Morris, to whom Pollock addressed his billing records, perpetuated the use of the dollar sign, and was the first high gov ernment official to give his blessing to the “s” with the two lines through it.The appearance of the dollar sign in print, in a 1797 book by Chauncey Lee, signified the acceptance of the dollar as a purely American symbol.Carlisle: 卡莱尔plantation owner: 种植园主outpost: 前哨peso: 比索penmanship: 书法monetary system: 货币体系revamp: 修补vestige: 残余美元的符号＄是怎么来的DOLLAR 美元美元的符号$的起源与好几种民间传说有关。
牺牲在陕北的中央红军团以上干部
牺牲在陕北的中央红军团以上干部1、吴起镇牺牲的2纵队10大队队长——黄珍黄珍(？——1935)，又名王珍。
湖北阳新人，中国共产党党员。
1930年参加红军。
后任红3军团班长、排长、连长、营长，福建军区闽中独立团团长，红3军团5师13团团长，3军10团团长，红军陕甘支队第2纵队10大队大队长。
参加了中央苏区历次反“围剿”斗争和中央红军长征。
1935年10月21日，在陕北吴起镇“割尾巴”战斗中英勇战斗，壮烈牺牲。
战后，陕甘支队政治部发表“庆祝我们进入陕北苏区的第一个大胜利”的捷报，对黄珍同志带领的10大队予以表扬，对黄珍同志的牺牲表示哀悼，号召全体指战员继承黄珍同志的遗志，为苏维埃事业奋斗到底！捷报中说：“这次战斗中，我们全支队的指战员都表示出无上的英勇气概，为苏维埃的事业而奋斗到底的决心。
特别值得表扬的是我们光荣的10大队。
10大队全体指战员，在这次战斗中，表现了无上的坚决顽强，无论如何要完成上级命令的决心。
他们在最艰难的环境之下，作最残酷的斗争，使我们整个的支队能够顺利击溃敌人。
10大队队长黄珍同志，在这次战斗中光荣地为苏维埃流了最后一滴血，这是最值得我们追悼的。
我们要继续黄珍同志的遗志而奋斗！”2、吴起镇牺牲的3军团秘书长——李鸣铁李鸣铁(1898——1935)，曾用名李民铁、李气象、李源刘。
1898年生，湖南资兴人。
1926年10月，在资兴县立中学积极筹建“学生联合会”，参加各种社会活动。
1927年3月，投身农民运动，为资兴县北乡区农运负责人之一。
“马日事变”后潜入地下，在北乡区、西乡区一带发动了抗租运动。
同年6月，加入中国共产党。
大革命失败后，参加组织农民武装斗争。
1928年1月，参加湘南起义，任苏维埃政府秘书长。
3月中旬，参加何长工率领前来接应湘南起义的工农革命军第2团，任4连文书兼连党支部委员。
4月，随朱德上井冈山，参加了巩固与发展井冈山革命根据地的斗争。
5月，正式成立中国工农红军第4军，任红4军11师32团4连党代表。
PID参数设定方法
PID 参数的设定：是靠经验及工艺的熟悉，参考测量值跟踪与设定值曲线，从而
PID 控制器参数的工程整定,各种调节系统中 P.I.D 参数经验数据以下可参照：
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PID 控制器的参数整定是控制系统设计的核心内容。 它是根据被控过程的特性确 定 PID 控制器的比例系数、 积分时间和微分时间的大小。PID 控制器参数整定的 方法很多，概括起来有两大类：一是理论计算整定法。它主要是依据系统的数学 模型， 经过理论计算确定控制器参数。这种方法所得到的计算数据未必可以直接 用，还必须通过工程实际进行调整和修改。二是工程整定方法，它主要依赖工程 经验，直接在控制系统的试验中进行，且方法简单、易于掌握，在工程实际中被 广泛采用。PID 控制器参数的工程整定方法，主要有临界比例法、反应曲线法和 衰减法。三种方法各有其特点，其共同点都是通过试验，然后按照工程经验公式 对控制器参数进行整定。 但无论采用哪一种方法所得到的控制器参数，都需要在 实际运行中进行最后调整与完善。 现在一般采用的是临界比例法。利用该方法进 行 PID 控制器参数的整定步骤如下：(1)首先预选择一个足够短的采样周期让系
� 使用 Kp 自适应功能有增加系统的快速响应及减少系统振荡
� 微分时间约为积分时间的 1/10----1/5 ，如果系统扰动比较大， 则微分时间应设得小一些
PID 参数是根据控制对象的惯量来确定的。大惯量如：大烘房的温度控制，一般 P 可在 10 以上,I=3-10,D=1 左右。小惯量如：一个小电机带一水泵进行压力闭环控制，一般只用 PI 控 制。P=1-10,I=0.1-1,D=0,这些要在现场调试时进行修正的。 1、让调节器参数积分系数 S0=0，实际微分系数 k=0，控制系统投入闭环运行，由小到大 改变比例系数 S1，让扰动信号作阶跃变化，观察控制过程，直到获得满意的控制过程为止。
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为抑制“两高一资”中国出口焦炭出口关税上调至40%据悉,财政部紧急发布通知,从8月20日开始对部分商品出口关税税率进行调整,涉及铝合金、焦炭、炼焦煤和其它烟煤。
其中,一般贸易项下出口的铝合金将征收出口暂定关税,暂定税率为15%；焦炭的出口暂定税率由25%提高至40%；炼焦煤出口暂定税率由5%提高至10%；其它烟煤等征收出口暂定关税,暂定税率为10%。
这已经是国家今年第二次采取措施抑制煤炭出口,早在年初,焦炭出口税率便已由15%上调至25%,同时还提高了焦炭出口企业的资质门槛。