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外文資料翻譯
PLC Studies in China as a Contribution to the Development of International Standards
Abstract
In the field of PLC, the standardization process on international level is progressing very slowly. The EMC Laboratory of the North China Electric Power University has received the task to develop a measurement method for the field radiated by PLC installations and a standard to be used in the future for the regulation of the PLC deployment. After a short introduction of the standardization process at international level, the paper presents measurements performed at the North China Electric Power University of radiated fields due to PLC. Comparisons of the field with various limits are shown. Finally the paper also presents a review of the regulatory situation on international level.
Keywords: PLC, standardization, electromagnetic disturbances.
1. Introduction
In the last 6 to 7 years, feasibility studies have been performed in various countries to check the possibility of using the low voltage distribution network to provide data transmission and eventually also telephonic links to individual customers at frequencies up to 30 MHz. This new technology is called Power Line Communication (PLC). This application is particularly interesting for power utilities which, on one side can enter in this way the telecommunication market and use their network for power network data transmission, on the other side can use this technology to control their own network.
However, this transmission mode in the frequency band extending from 1.6 to 30 MHz presents various and quite complex EMC problems. The main problem isproduction of disturbances in the network and in the environment.
2. Disturbance sources
The sources of disturbance are both radiated and conducted:
- the emission of electromagnetic noise which can interfere with radio communications for safety or military use, or disturb the radio amateurs；
- conducted differential and common mode currents can penetrate in any equipment connected to the network in which PLC is working. The disturbances have two types of origins:
- the signal source asymmetry, due to the coupler asymmetry；
- the unbalance of the Low Voltage Distribution Network (LVDN) and as a result an common mode to differential mode conversion.
The conversion from differential to common mode due to the network
unbalance has been analysed in various paper, as for instance in [1]. Different mitigation solutions have been also been proposed in the literature , but the research work must be further continued.
3. Standardization at international level
Concerning EMC problems, at an international level, two types of standards must be developed:
- a product standard；
- a network standard.
3.1 The product standard
The product standard should be an amendment of the CISPR22 standard and is the task of the Subcommittee CISPR.
A first idea was to extend the concept of Longitudinal Conversion Loss (LCL) specific for symmetric telecommunication pairs of wire to the non symmetric power network.
Measurements performed in various power networks, as those shown in Fig. 1, have given a large spread of LCL values .
It was not possible to arrive to a consensus for the concept based on the LCL value, to be used for the calculation of a voltage limit at the ports of the equipment connected to the network, although that this concept has been well-established for the case of telecommunication lines. After about 4 years of work and a whole series of documents at CD (Committee Draft) stage, the concept did not find the requested qualified majority for approval by the CISPR/I/ although that it found majority approval within the working group. It was decided to re-start the work evaluating a new basis.
A New Work Item Proposal (NWIP) was prepared by the French national Committee and approved in April 2005 [6]. The work will not be focused any more on the LCL value, but will try to:
- describe the typical electricity installations where it is intended to connect PLC equipment；
- identify the potentially disturbed services/equipment for each typical section of electricity installations described above；
- assess the level of protection currently provided by the CISPR22
for each equipment/service；
- set radiated and conducted limits for emissions of each typical section of electricity installation when PLC is operating.
The work started in June 2005 and is currently in progress.
3.2 Network standard
The European Commission has issued in 2001 the Mandate 313 which gives CENELEC and ETSI the task to develop a standard, to define emission limits for all communication networks including PLC.
Different limits have been proposed by various countries (Germany, UK, Norway) and entities (CENELEC, FCC, BBC). The differences between the various proposals were quite large and it was not possible to reach a consensus.
A Joint Working Group ETSI/CENELEC has produced several drafts, which have all failed to be approved by the National Committees.
4. PLC activity at the North China Electric Power University
4.1 Mandate given to the EMC Laboratory
In China, the Telecommunication Center of the China National Power Grid is supervising the PLC deployment over the whole country as a provider of service, but not as a regulatory authority. The Telecommunication Center has given to the EMC Laboratory of the North China Electric Power University the mandate to develop:
- a measurement method for the field；
- a standard which should be used in the future as a basis for the regulation of the PLC deployment.
These studies are a contribution, together with other research activities in Europe like the European Project OPERA, to the development of international standards.
4.2 Experimental measurements
In order to simulate the PLC operation environment, an experimental network was set up. Its structure is presented in Fig. 2.
As seen in Fig.2, the field was measured with a loop antenna which gives the magnetic field value. The conversion to electric field was performed by multiplying the measured values by the vacuum impedance (377 ohms). It is clear that in near fields, the value of the vacuum impedance is higher than 377 ohms and a better approach to convert magnetic to electric fields in such configurations is under study.
As a pair of PLC modems with rate of 200Mbps being used to download data from internet, the radiated field was also measured and shown in Fig.4. The radiation field was above all of the three limits.
The dimensions of the room were 9.45×6.8m. Three power distribution branches have been installed in the test. The first branch supplied three daylight lamps； the second branch a high-powered air conditioning； the third one five household electric appliances, including a refrigerator, a computer, a microwave oven, a washer, and a TV set each of it at distances of 10 meters. PLC signals were coupled at the outlet of the energy meter. A loop antenna was placed 3 meters away from the power line.
A PLC router and PLC modems composed of the LAN at nominal rates of 14Mbps, 45Mbps and 200Mbps to simulate the PLC internet access have been used. An example of the radiated electric field measured in the room is presented in Fig.3.
When using the PLC modems, besides shutting them down and transferring data with the internet at relatively high rate, there is another possible state: standby. In this state, the PLC modem is powered on, but it isn’t used to transfer data by the customer. The radiated field of a pair of PLC modems with a rate of 45Mbps in standby state was also measured and shown in Fig.5. Compared with the background, it appears that the radiation of the PLC network is significant when the PLC modem is in standby especially from 18MHz to 23MHz.
Fig.6 shows the measured radiation fields with different load conditions. The dotted line presents the condition when all household electric appliances were on, and the solid line presents the “off” condition. Fig.6 shows that the radiation fields did not
vary significantly when the household electric appliances were “on” and “off”.
Another interesting item investigated at the North China Electric Power University EMC Laboratory was the relation between the injected current and the radiation field strength. Generally, if this relation is known and it if is stable enough, then we can assess the emission level to some extent by measuring the injected current. Therefore, the injected current was measured in parallel with the field. Fig.7 shows the relation between the injected current and the radiation field in the frequency domain for the 45Mbps network. A rather good correlation was found except for frequencies in the range of about 16 to 24 MHz. The quantitative transfer relation for a typical network structure is still under investigation.
5. Regulatory approaches for access networks in Europe and USA
5.1 European Union regulation
The Communication Committee (COCOM) of the European Commission (EC) has delivered a positive message on the Draft Recommendation on Broadband Communications from 6 April 2005. This recommendation is very similar to the “Report and Order” published by the FCC on October 14, 2004.
The main features of this recommendation are:
- It requires that Regulatory Authorities should not follow the ex-ante approach for PLC deployment and operation. That means that PLC equipment should have easy market access and that an authorization is only required in case of harmful interference within a specific location at a specific frequency；
- the PLC equipment is regarded as a telecommunication equipment and as a consequence should follow the CE certification；
- it requires that PLC systems should be installed and operated according to good engineering principles；
- it recognizes the right of countries to take special restriction measures if necessary, for instance frequency restrictions in specific areas (military, coast where ship navigation can be affected), or fir frequencies of specific use (fire alarm).
Misunderstandings by EU member states are minimized by the recommended permanent dialogue towards the EC.
5.2 USA regulation
As an amendment to Part 15 of its rules, the Federal Communication Commission (FCC) has published on 14 October 2004 the “Report and Order”, which defines the BPL (Broadband Power Lines, name of PLC in US) regulation for Access PLC.
Access BPL systems will operate on an unlicensed non-interference basis under Part 15 model.
This means that the permitted limits are those defined by FCC Part 15, i.e.62 dBμV/m (see Fig. 3) and that the FCC will ask for a decrease of these limits or mitigation measures only in case of
Interference.
In addition, in order to achieve this goal the “Report and Order” specifies that the FCC:
- can decide that BPL must avoid specific frequencies and can decide to shut down any unit in the case of harmful interference；
- establishes “exclusion zones” in locations close to sensitive operations, such as coast guard or radio astronomy stations, within BPL must avoid operating on certain frequencies；
- establishes consultation requirements with public safety agencies, federal government sensitive stations and aeronautical stations；
- establishes a publicly available Access BPL notification database to facilitate an organized approach to identification and resolution of harmful interference；
- changes the equipment authorization for Access BPL systems from
verification to certification；
- improves measurement procedures for all equipment that use RF energy to communicate over power lines.
6. Conclusion
The Power Line Communication represents a very promising technique,
permitting to extend internet, voice phone and digital TV everywhere where exists a Low Voltage Distribution Network.
However, a few EMC problems should still be solved, in order to avoid disturbances.
On international level, the standardization work is progressing very slowly, due to many divergent approaches and lack of some technical solutions.
The measurements performed in the experimental network of the EMC.Laboratory of the North China Electric Power University, show that the radiated fields are related with the work state and the transfer rate of the PLC modems. Especially for the higher rate, the radiated fields are beyond limits of NB30, ITU K60 and even FCC Part15. The research work performed in this university, together with studies taking place in other universities in the world, will contribute to a better understanding of the behavior of the reducing the disturbances and to permit the development of standards compatible with the commercial interests and with the protection of consumers.
Acknowledgment
This work is supported by the National Natural Science Foundation of China (project 60571030).
國(guó)際標(biāo)準(zhǔn)的發(fā)展促進(jìn)國(guó)內(nèi)PLC的研究
摘要
在該領(lǐng)域的PLC ，標(biāo)準(zhǔn)化進(jìn)程，國(guó)際一級(jí)的進(jìn)展十分緩慢。 EMC的實(shí)驗(yàn)室，華北電力大學(xué)收到了任務(wù)，制定一個(gè)測(cè)量方法，為外地輻射裝置用PLC和標(biāo)準(zhǔn)，用于在今后的監(jiān)管的PLC部署。經(jīng)過(guò)簡(jiǎn)短介紹的標(biāo)準(zhǔn)化進(jìn)程在國(guó)際一級(jí)，提出了測(cè)量數(shù)據(jù)進(jìn)行的華北電力大學(xué)的輻射領(lǐng)域，由于PLC的。比較外地的各種限制顯示。最后，文件還提出了審查監(jiān)管情況，國(guó)際一級(jí)。
關(guān)鍵詞： PLC ，標(biāo)準(zhǔn)化，電磁干擾。
1 .導(dǎo)言
在過(guò)去6至7年，可行性研究已經(jīng)完成在不同國(guó)家，以檢查是否有可能利用低壓配電網(wǎng)絡(luò)，使數(shù)據(jù)傳輸和電話(huà)聯(lián)系，最終也對(duì)個(gè)人客戶(hù)的頻率高達(dá)30 MHz的。這一新技術(shù)被稱(chēng)為電力線通信（ PLC ）的。這種應(yīng)用是特別有趣的是電力，一方可以以這種方式進(jìn)入電信市場(chǎng)，并利用其網(wǎng)絡(luò)，電力網(wǎng)絡(luò)的數(shù)據(jù)傳輸，另一邊可以使用此技術(shù)來(lái)控制自己的網(wǎng)絡(luò)。
然而，這種傳輸模式中頻段從6月1日至30兆赫的各種禮物和相當(dāng)復(fù)雜的電磁兼容問(wèn)題。主要的問(wèn)題isproduction的網(wǎng)絡(luò)中的干擾和環(huán)境。
2 .干擾源
干擾的來(lái)源都是輻射，并進(jìn)行：
-排放的電磁噪聲，可干擾無(wú)線電通訊的安全或軍事用途，或干擾無(wú)線電業(yè)余愛(ài)好者；
-進(jìn)行差分和共模電流可以穿透任何設(shè)備連接到網(wǎng)絡(luò)中，公司正在努力。騷亂有兩種類(lèi)型的來(lái)源：
-信號(hào)源的不對(duì)稱(chēng)，由于耦合不對(duì)稱(chēng)；
-不平衡的低壓配電網(wǎng)（ LVDN ） ，因此一個(gè)共同的模式，以差模轉(zhuǎn)換。
轉(zhuǎn)換差別的共同模式由于網(wǎng)絡(luò)不平衡分析了各種文件，例如在不同的解決方案已經(jīng)緩解還提議在文獻(xiàn)，但研究工作必須進(jìn)一步繼續(xù)。
3 .標(biāo)準(zhǔn)化在國(guó)際一級(jí)
關(guān)于電磁兼容問(wèn)題，在國(guó)際層面上，兩種類(lèi)型的標(biāo)準(zhǔn)，必須制訂：
-產(chǎn)品標(biāo)準(zhǔn)；
-網(wǎng)絡(luò)標(biāo)準(zhǔn)。
3.1產(chǎn)品標(biāo)準(zhǔn)
產(chǎn)品標(biāo)準(zhǔn)應(yīng)修改CISPR22標(biāo)準(zhǔn)的任務(wù)是小組委員會(huì)的CISP。
第一個(gè)想法是的概念擴(kuò)大縱向轉(zhuǎn)換損耗（柜）具體對(duì)稱(chēng)雙絲電信的非對(duì)稱(chēng)電網(wǎng)。
表現(xiàn)在各種測(cè)量電力網(wǎng)絡(luò)，因?yàn)檫@些顯示圖，給予了大量的傳播拼箱值。
這是不可能達(dá)成協(xié)商一致的概念基礎(chǔ)上拼箱值，用于計(jì)算的電壓限制在港口的設(shè)備連接到網(wǎng)絡(luò)，但這個(gè)概念已經(jīng)被確立為案件電信線路。經(jīng)過(guò)大約4年的工作和一系列文件光盤(pán)（委員會(huì)草案）階段，這一概念沒(méi)有找到所要求的合格的多數(shù)批準(zhǔn)的CISPR /我/雖然，它發(fā)現(xiàn)了多數(shù)人的贊同在工作組內(nèi)。這是決定重新開(kāi)始新的工作評(píng)價(jià)的基礎(chǔ)。
一項(xiàng)新的工作項(xiàng)目提案（ NWIP ）是由法國(guó)國(guó)家委員會(huì)，并核準(zhǔn)于2005年4月這項(xiàng)工作將無(wú)法集中更多的拼箱價(jià)值，但將努力：
-描述了典型的電力設(shè)施的地方是連接PLC設(shè)備；
-確定潛在的不安服務(wù)/設(shè)備為每個(gè)典型部分電力設(shè)施上文所述；
-評(píng)估的保護(hù)水平，目前提供的CISPR22為每個(gè)設(shè)備/服務(wù)；
-建立輻射和排放量進(jìn)行限制，每一個(gè)典型的電力安裝一節(jié)時(shí)， PLC的運(yùn)行。
這項(xiàng)工作開(kāi)始于2005年6月，目前正在取得進(jìn)展。
3.2網(wǎng)絡(luò)標(biāo)準(zhǔn)
歐盟委員會(huì)已經(jīng)于2001年發(fā)布的任務(wù)313使CENELEC和ETSI的任務(wù)是制定標(biāo)準(zhǔn)，確定排放限值的所有通信網(wǎng)絡(luò)，包括PLC的不同的限制提出了不同的國(guó)家（德國(guó)，英國(guó)，挪威）和實(shí)體（ CENELEC ，催化裂化，英國(guó)廣播公司） 。之間的分歧的各種建議是相當(dāng)大，因此無(wú)法達(dá)成共識(shí)。
聯(lián)合工作組的ETSI / CENELEC編制了若干草案，這都沒(méi)有得到批準(zhǔn)的全國(guó)委員會(huì)。
4 . PLC的活動(dòng)在華北電力大學(xué)
4.1授權(quán)的電磁兼容實(shí)驗(yàn)室
在我國(guó)，電信中心，中國(guó)國(guó)家電網(wǎng)公司是監(jiān)督部署對(duì)整個(gè)國(guó)家作為一個(gè)供應(yīng)商的服務(wù)，而不是作為一個(gè)監(jiān)管機(jī)構(gòu)。電信中心已考慮到電磁兼容實(shí)驗(yàn)室的華北電力大學(xué)開(kāi)發(fā)的任務(wù)：
-一種測(cè)量方法的領(lǐng)域；
-一個(gè)標(biāo)準(zhǔn)的，應(yīng)在將來(lái)使用，以此為基礎(chǔ)的PLC部署。
這些研究的貢獻(xiàn)，連同其他研究活動(dòng)在歐洲象歐洲項(xiàng)目歌劇，向國(guó)際標(biāo)準(zhǔn)的發(fā)展。
4.2實(shí)驗(yàn)測(cè)量
為了模擬PLC的經(jīng)營(yíng)環(huán)境，實(shí)驗(yàn)網(wǎng)絡(luò)正式成立。其結(jié)構(gòu)如圖2 ，實(shí)地測(cè)量的環(huán)形天線使磁場(chǎng)價(jià)值。轉(zhuǎn)換電場(chǎng)是由乘以測(cè)量值的真空阻抗（ 377歐姆） 。顯然，在不久的領(lǐng)域，其價(jià)值的真空阻抗高于377歐姆和更好的方法來(lái)轉(zhuǎn)換磁場(chǎng)對(duì)電場(chǎng)在這種配置目前正在研究。
作為一個(gè)對(duì)PLC的調(diào)制解調(diào)器的速度200Mbps被用來(lái)從互聯(lián)網(wǎng)下載數(shù)據(jù)的輻射場(chǎng)也是衡量和顯示在圖4 。輻射場(chǎng)是最重要的三個(gè)限制的尺寸為9.45 ×房間六點(diǎn)八米，三峽電力分配部門(mén)已經(jīng)安裝測(cè)試。第一個(gè)分支提供三個(gè)日光燈；第二處高功率的空調(diào)；第三個(gè)五年家用電器，包括冰箱，電腦，微波爐，洗衣機(jī)和一臺(tái)電視機(jī)，在每一個(gè)距離10米。 PLC的信號(hào)，再加上出口的電能表。循環(huán)天線被置于3米遠(yuǎn)離電力線。
PLC與PLC調(diào)制解調(diào)器路由器組成的局域網(wǎng)的名義利率14Mbps ， 45Mbps和200Mbps模擬PLC的互聯(lián)網(wǎng)接入已經(jīng)使用。一個(gè)例子輻射電場(chǎng)測(cè)量室介紹圖。
當(dāng)使用的PLC調(diào)制解調(diào)器，除了關(guān)閉他們失望和傳輸數(shù)據(jù)與互聯(lián)網(wǎng)在相對(duì)較高的利率，還有一個(gè)可能的狀態(tài)：待命。在此狀態(tài)下， PLC的調(diào)制解調(diào)器的電源，但它不是用來(lái)傳輸數(shù)據(jù)的客戶(hù)。輻射場(chǎng)對(duì)PLC的調(diào)制解調(diào)器的速度45Mbps在待機(jī)狀態(tài)也是衡量和圖5所示。與背景，似乎輻射的PLC網(wǎng)絡(luò)具有重要意義時(shí)， PLC的調(diào)制解調(diào)器在待機(jī)特別是從達(dá)18MHz到23MHz 。
圖6顯示了測(cè)量輻射領(lǐng)域不同負(fù)載條件下。虛線提出的條件時(shí)，所有的家用電器上，而實(shí)線介紹了“關(guān)閉”狀態(tài)。圖6表明，沒(méi)有輻射領(lǐng)域差別很大時(shí)，家電是“上”和“關(guān)閉” 。
另一個(gè)令人感興趣的項(xiàng)目調(diào)查，在華北電力大學(xué)電磁兼容實(shí)驗(yàn)室是關(guān)系注入電流和電場(chǎng)強(qiáng)度的輻射。一般來(lái)說(shuō)，如果這種關(guān)系是已知的和穩(wěn)定的，如果是不夠的，那么我們可以評(píng)估排放水平在一定程度上通過(guò)測(cè)量注入電流。因此，注入電流測(cè)量平行與外地。圖7顯示之間的關(guān)系注入電流和輻射場(chǎng)的頻域的45Mbps網(wǎng)絡(luò)。一個(gè)比較良好的相關(guān)性，發(fā)現(xiàn)除了頻率范圍約16至24兆赫。轉(zhuǎn)讓的數(shù)量關(guān)系的一個(gè)典型的網(wǎng)絡(luò)結(jié)構(gòu)仍在調(diào)查之中。
5 .管理辦法的接入網(wǎng)絡(luò)在歐洲和美國(guó)
5月1日歐洲聯(lián)盟條例通信委員會(huì)（巴統(tǒng)）的歐洲委員會(huì)（ EC ）帶來(lái)了一個(gè)積極的信息對(duì)建議草案的寬帶通信從2005年4月6日。這項(xiàng)建議是非常類(lèi)似的報(bào)告“和秩序”出版由FCC于2004年10月14號(hào)。主要特點(diǎn)，這一建議是：
-它要求監(jiān)管當(dāng)局不應(yīng)按照事前辦法PLC的部署和行動(dòng)。這意味著，公司設(shè)備應(yīng)具有方便的市場(chǎng)準(zhǔn)入，并授權(quán)只須在案件內(nèi)的有害干擾的具體位置在特定的頻率；
-的PLC設(shè)備被視為電信設(shè)備，因此應(yīng)遵循CE認(rèn)證；
-它要求PLC系統(tǒng)應(yīng)安裝和操作按照良好的工程原則；
-它承認(rèn)各國(guó)有權(quán)采取特別限制措施，如果有必要，例如頻率限制在特定領(lǐng)域（軍事，海岸船舶航行可能受到影響） ，或飛行情報(bào)區(qū)的具體使用頻率（火災(zāi)報(bào)警） ，誤解了歐盟成員國(guó)盡量減少長(zhǎng)期對(duì)話(huà)的建議對(duì)歐共體。
5.2美國(guó)監(jiān)管
作為修正案的第15部分的規(guī)定，聯(lián)邦通訊委員會(huì)（ FCC ）發(fā)表了關(guān)于2004年10月14 “報(bào)告和秩序” ，它確定了電力線寬帶（寬帶電力線，名稱(chēng)的PLC在美國(guó)）規(guī)例獲取PLC的。
電力線寬帶接入系統(tǒng)將在一間無(wú)牌經(jīng)營(yíng)不干預(yù)的基礎(chǔ)上根據(jù)15模型。這就是說(shuō)，允許限額所規(guī)定的FCC Part 15的， ie62 dBμV /平方米（見(jiàn)圖3） ，并要求聯(lián)邦通信委員會(huì)將減少或減輕這些限制措施只能在案件干涉。
此外，為了實(shí)現(xiàn)這一目標(biāo)“報(bào)告和秩序”中指定的催化裂化：
-可以決定BPL公司必須避免特定頻率和可以決定關(guān)閉任何單位的情況下有害干擾；
-建立“禁區(qū)”的地點(diǎn)接近敏感的業(yè)務(wù)，如海岸警衛(wèi)隊(duì)或射電天文站，必須避免在電力線寬帶業(yè)務(wù)在某些頻率；
-建立磋商要求公眾安全機(jī)構(gòu)，聯(lián)邦政府的敏感和航空站；
-建立了一個(gè)公開(kāi)的訪問(wèn)BPL的通知數(shù)據(jù)庫(kù)，以促進(jìn)一個(gè)有組織的方法來(lái)識(shí)別和解決有害干擾；
-改變了設(shè)備的授權(quán)，電力線寬帶接入系統(tǒng)核查驗(yàn)證；
-提高了測(cè)量程序，對(duì)所有設(shè)備的能源使用射頻通訊電力線路上。
6 .結(jié)論
電力線通訊是一個(gè)非常有前景的技術(shù)，允許延長(zhǎng)互聯(lián)網(wǎng)，語(yǔ)音電話(huà)和數(shù)字電視在世界各地存在著一種低壓配電網(wǎng)。但是，有少數(shù)的EMC問(wèn)題，仍然應(yīng)該得到解決，以避免干擾。在國(guó)際一級(jí)，標(biāo)準(zhǔn)化工作進(jìn)展非常慢慢地，由于許多不同的辦法和缺乏一些技術(shù)解決方案。測(cè)量完成實(shí)驗(yàn)網(wǎng)絡(luò)的EMC實(shí)驗(yàn)室華北電力大學(xué)，表明，輻射相關(guān)領(lǐng)域的工作狀態(tài)和傳輸速率的PLC調(diào)制解調(diào)器。特別是較高的利率，輻射領(lǐng)域超出限度NB30 ，國(guó)際電聯(lián)K60 ，甚至催化裂化Part15 。這項(xiàng)研究工作在這所大學(xué)，研究一起發(fā)生在其他大學(xué)在世界上，將有助于更好地理解的行為減少了干擾，并允許制定標(biāo)準(zhǔn)兼容的商業(yè)利益與保護(hù)消費(fèi)者的利益。
致謝
這項(xiàng)工作得到了國(guó)家自然科學(xué)基金資助項(xiàng)目（項(xiàng)目六千零五十七點(diǎn)一零三萬(wàn)） 。
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