无选择的

No He won't have it , he knows his whole back city's ropes It don't matter, he's dope He knows that, but he's broke He's so stacked that he knows When he goes back to his mobile home, that's when it's Back to the lab again yo This whole rap shit He better go capture this moment and hope it don't pass him You better lose yourself in the music, the moment You own it, you better never let it go You only get one shot, do not miss your chance to blow This opportunity comes once in a lifetime yo The soul's escaping, through this hole that it's gaping This world is mine for the taking Make me king, as we move toward a, new world order A normal life is borin, but superstardom's close to post mortar It only grows harder, only grows hotter He blows us all over these hoes is all on him Coast to coast shows, he's know as the globetrotter Lonely roads, God only knows He's grown farther from home, he's no father He goes home and barely knows his own daughter But hold your nose cuz here goes the cold water His bosses don't want him no mo, he's cold product They moved on to the next schmoe who flows He nose dove and sold nada So the soap opera is told and unfolds I suppose it's old potna, but the beat goes on Da da dum da dum da da You better lose yourself in the music, the moment You own it, you better never let it go You only get one shot, do not miss your chance to blow This opportunity comes once in a lifetime yo No more games, I'ma change what you call rage Tear this mothafuckin roof off like 2 dogs caged I was playin in the beginnin, the mood all changed I been chewed up and spit out and booed off stage But I kept rhymin and stepwritin the next cypher Best believe somebody's payin the pied piper All the pain inside amplified by the fact That I can't get by with my 9 to 5 And I can't provide the right type of life for my family Cuz man, these goddam food stamps don't buy diapers And it's no movie, there's no Mekhi Phifer, this is my life And these times are so hard and it's getting even harder Tryin to feed and water my seed, plus See dishonor caught up bein a father and a prima donna Baby mama drama's screamin on and Too much for me to wanna Stay in one spot, another jam or not Has gotten me to the point, I'm like a snail I've got to formulate a plot fore I end up in jail or shot Success is my only mothafuckin option, failure's not Mom, I love you, but this trail has got to go I cannot grow old in Salem's lot So here I go is my shot.

无 他不会有，他知道他的整个回城的绳索它不处理此事，但他的涂料他知道，但他的突破他的，所以堆叠他知道当他回到他的手机在家，就什么时候，它的回到实验室又摇摇这整个说唱为Shit 他最好去捕捉这一刻，并希望它不通过他您更好地失去了自己在音乐，时刻你拥有它，你最好永远不会放手你只能获得一杆，千万不要错过你的机会，以打击这个机遇而来的一生中只有一次的心灵灵魂的逃亡，透过这个洞，它的溃烂这个世界是矿井为录取令我国王，因为我们走向一个新的世界秩序过正常的生活，是borin ，但superstardom的接近邮政砂浆它不仅日益困难，只有长大白热化他的打击我们所有这些锄头，是所有对他的海岸到海岸的表演，他知道作为globetrotter 寂寞的道路，只有上帝知道他的成长到离家远，他的父亲并没有他回家，勉强知道自己的女儿但对于你的鼻子cuz这里有云冷水他的老板不希望他没有谟，他的冷战产物他们转移到下一schmoe谁流向他的鼻子鸽派和出售纳达所以肥皂歌剧是告诉，并逐步落实我想它的旧potna ，但在街上巡逻下去大达达姆弹达达姆弹达大您更好地失去了自己在音乐，时刻你拥有它，你最好永远不会放手你只能获得一杆，千万不要错过你的机会，以打击这个机遇而来的一生中只有一次的心灵没有更多游戏，我是改变你们称之为愤怒催泪这mothafuckin屋顶起飞一样二日犬笼我是playin在beginnin ，心情，一切都变了我是咀嚼起来，吐出一片嘘声起飞阶段但我一直rhymin和stepwritin未来的CYPHER 最好相信有人的payin该pied伯尔所有的痛苦内扩增事实我不能得到我的9至5月我不能提供适当类型的生命，因为我的家庭 cuz男子，这些goddam粮票不买尿布它的不看电影，有没有mekhi phifer ，这是我的生命这些时代，所以很难和它变得更难 tryin到饲料和水我的种子，加上见荣辱赶上了bein父亲和表面唐娜宝宝妈妈戏剧的尖叫和太多，我想留在现场的一个，另一个果酱或不得到了我的一点，我想蜗牛我必须制订一项阴谋前列我结束了在监狱或打针成功是我唯一的mothafuckin选择，失败的不是妈妈，我爱你，但这个线索已经去我不能老在塞勒姆的地段所以在这里，我去的是我的了一枪。

Dealcoholization temperature markedly influences the surface area and porosity of the resultant MAO-supports. When the support was pretreated at lower or higher temperature, the corresponding MAO-support shows very low surface area;2.XRD and IR analyses indicate that MAO has reacted with the residual ethanol in the supports, which is an important manner to get MAO fixed on the carrier. Morever, XPS analyse indicates that MAO can also be coordinated with MgCl_2, which is another way to get MAO fixed on the support;3.ICP and EDX analyses indicate that dealcoholization temperature not only determined the element content on the solid catalyst, but also influences the element distribution on the carrier;4.The activities of the supported phenoxy-imine catalysts and the properties of resultant polymers are strongly dependent on the dealcoholization temperature. The support (MSP-5) obtained by treating MgCl_2·2.56C_2H_5OH at 160℃for 4 h, then modified by MAO is very effective for immobilizing complex 3, the resultant solid catalyst (MSPC-5) shows very high activity in ethylene polymerization, and its kinetics of polymerization is stable during the reaction process. Finally, PEs with spherical morphology and high bulk density (over 0.35g/ml) were obtained, without reactor fouling;5.In this work, polymerization conditions such as alkylaluminums, Al/Zr ratio, temperature and H_2 had a pronounced effect on the activity of MSPC-5 and properties of PE;(3). New MgCl_2-Supported Single-Site Catalysts for Ethylene PolymerizationIn this work, a kind of new MgCl_2 support was obtained by anhydrous MgCl_2 co-milled with solid MAO, and it is a creative contribution. Then some single-site catalysts were supported on the new MgCl_2 support, and the resulted solid catalysts were tested in ethylene polymerization, the results indicated that:1.XRD and IR analyses indicate that MAO does be coordinated with MgCl_2, which is in good agreement with the results obtained by XPS;2.co-mlling time had no obvious effect on the texture of support after 12 hours;3.In this work, MgCl_2 was co-milled with solid MAO for different hours, and then complex 3 was supported on these co-milled supports. It was found that co-milling time markedly influences the activity of solid catalysts, but it had negligible effect on the kinetic profile and the properties of resultant PE.

XPS研究结果表明，MAO不仅仅只和乙醇作用，MAO还与MgCl_2本身有一定的作用，这是一个极为重要的发现；3、通过ICP和EDX表征，发现载体的脱醇温度直接影响着元素在固体催化剂中的含量及分布；4、脱醇温度极大地影响着负载苯氧基亚胺类催化剂的活性和聚合物的性能，特别是原始载体经160℃活化4小时制备得到的固体催化剂MSPC-5的活性明显高于其他脱醇温度条件下制得的固体催化，并且催化剂寿命长，表现出稳定的动力学行为，最终获得了高堆密度(大于0.35g／ml)的球形聚乙烯颗粒；5、本文选择MSPC-5为研究对象，考察了聚合反应参数对催化剂的活性及其聚合物的影响，研究发现：不同的烷基铝对催化剂具有非常重要的影响，特别足TIBA对MSPC-5的助催化活性最高，烷基铝的加入量有一个较佳值，聚合温度为80度时活性最高，H_2的加入使催化剂的活性明显降低且聚合物的分子量也减小；、新型氯化镁载体负载单活性中心催化剂催化乙烯聚合本文创造性采用固体MAO与无水氯化镁直接进行共研磨，制备出了一种的新型的氯化镁载体，并将该载体用于多种单活性中心催化剂的负载化研究，研究表明：1、通过BET、XRD的表征，再次证实了MAO与MgCl_2之间具有直接作用，与XPS的研究结果相一致；2、当研磨时间高于12小时时，延长研磨时间对载体的结构没有显著的影响；3、将配合物3负载于共研磨时间不同的一系列载体上，乙烯聚合结果表明，尽管共研磨时间对负载催化剂的活性具有明显的影响，但是它对聚合物的性能以及催化剂的影响不明显。

Dealcoholization temperature markedly influences the surface area and porosity of the resultant MAO-supports. When the support was pretreated at lower or higher temperature, the corresponding MAO-support shows very low surface area; 2.XRD and IR analyses indicate that MAO has reacted with the residual ethanol in the supports, which is an important manner to get MAO fixed on the carrier. Morever, XPS analyse indicates that MAO can also be coordinated with MgCl_2, which is another way to get MAO fixed on the support; 3.ICP and EDX analyses indicate that dealcoholization temperature not only determined the element content on the solid catalyst, but also influences the element distribution on the carrier; 4.The activities of the supported phenoxy-imine catalysts and the properties of resultant polymers are strongly dependent on the dealcoholization temperature. The support (MSP-5) obtained by treating MgCl_2·2.56C_2H_5OH at 160℃for 4 h, then modified by MAO is very effective for immobilizing complex 3, the resultant solid catalyst (MSPC-5) shows very high activity in ethylene polymerization, and its kinetics of polymerization is stable during the reaction process. Finally, PEs with spherical morphology and high bulk density (over 0.35g/ml) were obtained, without reactor fouling; 5.In this work, polymerization conditions such as alkylaluminums, Al/Zr ratio, temperature and H_2 had a pronounced effect on the activity of MSPC-5 and properties of PE;(3). New MgCl_2-Supported Single-Site Catalysts for Ethylene Polymerization In this work, a kind of new MgCl_2 support was obtained by anhydrous MgCl_2 co-milled with solid MAO, and it is a creative contribution. Then some single-site catalysts were supported on the new MgCl_2 support, and the resulted solid catalysts were tested in ethylene polymerization, the results indicated that: 1.XRD and IR analyses indicate that MAO does be coordinated with MgCl_2, which is in good agreement with the results obtained by XPS; 2.co-mlling time had no obvious effect on the texture of support after 12 hours; 3.In this work, MgCl_2 was co-milled with solid MAO for different hours, and then complex 3 was supported on these co-milled supports. It was found that co-milling time markedly influences the activity of solid catalysts, but it had negligible effect on the kinetic profile and the properties of resultant PE.

XPS研究结果表明，MAO不仅仅只和乙醇作用，MAO还与MgCl_2本身有一定的作用，这是一个极为重要的发现； 3、通过ICP和EDX表征，发现载体的脱醇温度直接影响着元素在固体催化剂中的含量及分布； 4、脱醇温度极大地影响着负载苯氧基亚胺类催化剂的活性和聚合物的性能，特别是原始载体经160℃活化4小时制备得到的固体催化剂MSPC-5的活性明显高于其他脱醇温度条件下制得的固体催化，并且催化剂寿命长，表现出稳定的动力学行为，最终获得了高堆密度(大于0.35g／ml)的球形聚乙烯颗粒； 5、本文选择MSPC-5为研究对象，考察了聚合反应参数对催化剂的活性及其聚合物的影响，研究发现：不同的烷基铝对催化剂具有非常重要的影响，特别足TIBA对MSPC-5的助催化活性最高，烷基铝的加入量有一个较佳值，聚合温度为80度时活性最高，H_2的加入使催化剂的活性明显降低且聚合物的分子量也减小；、新型氯化镁载体负载单活性中心催化剂催化乙烯聚合本文创造性采用固体MAO与无水氯化镁直接进行共研磨，制备出了一种的新型的氯化镁载体，并将该载体用于多种单活性中心催化剂的负载化研究，研究表明： 1、通过BET、XRD的表征，再次证实了MAO与MgCl_2之间具有直接作用，与XPS的研究结果相一致； 2、当研磨时间高于12小时时，延长研磨时间对载体的结构没有显著的影响； 3、将配合物3负载于共研磨时间不同的一系列载体上，乙烯聚合结果表明，尽管共研磨时间对负载催化剂的活性具有明显的影响，但是它对聚合物的性能以及催化剂的影响不明显。

As the first basic legal instrument that the European Communities have ever adopted as secondary legislation, Regulation on the law applicable to non-contractual obligations is examined and commented comprehensively and in depth. With regard to Regulation's scope, the paper accentuates the former' s wide applicability while forecasts the perplexity Member States may have on the issue of their own independent contracting right in the international arena; on the provisions of the Regulation about the applicable law of torts or delicts, unjust enrichment, negotiorum gestic and culpa in contrahendo, and common provisions, the paper reveals the rationales and ideas implied thereof, while comments critically the relevant loopholes or ambiguities.

以欧共体首次颁布的《非合同义务法律适用条例》（文中简称《2007年罗马二号条例》）的法律结构为基本框架，首先分析该条例的适用范围及其与欧共体其他二级立法和国际公约之间的关系，突出显示其在适用方面的广泛性，同时也指出成员国今后在独立对外缔约权方面将会面临的困惑；然后，通过对该条例关于侵权或过失不法行为、不当得利、无因管理和缔约过失责任的法律适用，当事人的法律选择自由以及相关配套制度的全面系统分析，揭示其隐含的法律原则和价值理念，同时指出其存在的漏洞和模糊之处。

Therefore, it can be regarded as a great improvement of the investment decision-making theory and methods .This article makes a systematic research on real options theory and method and its application, including the following several main aspects:Firstly, it makes a detailed discussion about the common theoretical basis of financial options and real options, including no-arbitrage equilibrium principle, risk-neutral definition, complete market and dynamic tracking.Secondly, it analyze three basic characteristic of investment decision-making in modern market economic system: irreversibility, uncertainty and flexibility, and from the angle of their mutual quantitative and qualitative interactions, it makes a comparison between the traditional NPV methods and real options methods and makes a summary of the general analytical methods of real options.Thirdly, it discusses the all elements in the application of real options such as the ^leakages in value of real assets, basis risk, and private risk, and furthermore, it attempts to put forth a normalized strategy of its application and construct a basic framework of its application.Fourthly, it applies real options theory to strategetic investment of enterprises and the buy-out of company, putting forth a value model for strategetic investment program and making a concrete analysis of its application to buy-out. Furthermore, it advocates that a flexible investment decision-making system should be setup according to real options theory in our country.

本文对实物期权理论和方法及其应用进行了系统研究，主要内容包括如下几个方面：(1)详细讨论了金融期权和实物期权共同的理论基础，主要包括无套利均衡原理、风险中性定义、完全市场以及动态复制方法，对这些理论方法的探讨既是本文的出发点和基础，它们提供了研究实际应用实物期权的一个基准点，也是贯穿全文的线索和灵魂；(2)分析了现代市场经济体系中投资决策的三个基本特征即不可逆性、不确定性和时机选择，并从它们数量上和质量上相互作用的重要意义的角度，分析了传统的净现值法与实物期权方法的差异，指出了净现值法在不确定环境中存在的缺陷及实物期权处理投资灵活性的价值，并将净现值法纳入实物期权投资分析决策体系当中，总结了企业投资决策实物期权的一般分析方法；(3)探讨了实物期权应用中要考虑的各种要素，如实物资产的价值漏损、基差风险和非市场风险等，并进一步提出了实物期权应用的规范化策略和构建了一个实际应用实物期权方法的基本框架，尝试将期权的基本原理与企业在现实经济环境中投资决策的要素结合起来，从而可以在一定程度上超越期权的复杂的数学计算而汲取期权思想的精华，从而促进期权决策方法在实际投资决策中的应用；(4)将实物期权方法应用于企业战略投资，得出了战略投资项目的价值模型，指出可以将实物期权理论和方法应用于企业并购，分析了应用的具体方面，并提出应根据实物期权理论建立一套适合我国企业的灵活的投资决策系统。

objective we start with clinical research to explore the ability and mechanism of ion conduction with chinese herbs to curing ovulatory obstacle.methods adopting the methods of clinical observation random contrast.select the cases of ovulatory obstacle dividing randomly into two groups:therapeutic group and control group,the patients of therapeutic group using ion conduction with chinese herbs with act'on nourishing blood and promoting blood circulation to dissipate blood stasis when follicle grow up to 1.4cm.we take the decoction of jia jian tao hong si wu tang conducting the unilateral lower abdomen which has the dominant follicle,treating continuously for 4～8 days and observing ovulation.the patients of control group inject hcg 10000unit when follicle grow up to 1.8cm and observing ovulation.appraising two groups ovulated rate and pregnancy rate,and detect fsh、lh、e2、p at sixteen to eighteen days of menstrual cycle.results ion conduction with chinese herbs can significantly inspires ovulation and its effection is evidently higher than control group and has a higher pregnancy rate,no side effect of ovarian hyperstimulation syndrome.conclusion ion conduction with chinese herbs has significant function on inspiring ovulation.the target effection of treating ovulatory obstacle is exact.this method has a ovulated rate and higher pregnancy rate.

采用临床观察、随机对照的方法，选择排卵障碍的患者，随机分为治疗组和对照组，治疗组在b超监测卵泡生长达到1.6cm时，给予具有养血、活血化瘀作用的加减桃红四物汤水煎剂，用离子导入仪将中药水煎剂导入有优势卵泡的一侧少腹部，连续治疗4～8时天，同时连续监测卵泡排出情况。对照组在b超监测卵泡达到1.8cm时，开始采用hcg10000u肌注，连续b超监测卵泡排出情况。评价两组排卵率及受孕率，同时在月经周期的第16～22天抽血查fsh、lh、e2、p。结果运用离子导入的方法将具有促排卵作用的加减桃红四物汤水煎剂导入有优势卵泡的一侧附件，其促排卵的作用优于用hcg肌注促排卵，而且受孕率高，无卵巢过激综合征之虞。结论中药离子导入具有显著的促排卵作用，其治疗排卵障碍的靶向作用确切，排卵率及受孕率高。

objective to evaluate efficacy of extracorporeal shock wave lithotripsyfor treating ureteral stones in situ,investigate the cause of higher re-treatment rate.methods total of 687 patients with ureteral stone were received eswl between january 2000 and december 2004,included 455 male(66.2%) and 232 female(33.8%) patients,6 cases have bilateral ureteral calculi,12 cases have unilateral multiple calculi.hence,together 709 ureteral calculi were treated.patients upper ureteral calculi were treated in the supine position,for lower ureteral calculi patients were turned prone.to reduce eswl-induced renal trauma and pain,using lower energy source,adjusted power setting from 9.8 to 13.2kv,limited 1500 shock wavs per one session.no auxiliary procedure were used before eswl.the stone size was measured as the surface area of stone length by stone width on x-ray film.the interval between two treatment sessions was two weeks.results of 709 ureteral calculi,the overall stone free rate was 97.3%(690 calculi),re-treatment rate was 34.1%(292 calculi).according to the performed treatment sessions,one session 467 calculi,the mean stone size 37.27mm2,stone free rate 65.4%(464 calculi).two sessions 138 calculi,the mean stone size 62.48mm2,stone free rate 18.4%(131calculi).three sessions 52 calculi,the mean stone size 79.60mm2,stone free rate 7.1%(50calculi).four sessions 19 calculi,the mean stone size 101.63mm2,stone free rate 2.4%(17calculi).fivesessions 33 calculi,the mean stone size 119.33mm2,stone free rate 3.9%(28 calculi).overall 19 cases(2.7%)turned to other treatment modalities.of 335 upper ureteral calculi,303 achieved stone free (95.8%),re-treatment rate was 38.5%(129 calculi).of 374 lower ureteral calculi,369 achieved stone free(98.7%),re-treatment rate was 30.2%(113 calculi).the re-treatment rate of upper ureteral calculi was higher than lower ureteral calculi(p＜0.05,χ2=5.40).the difference of stone-free rate between upper and lower ureteral calculi was no significant(p＞0.05,χ2=0.15).conclusion eswl should be considered first line therapy for ureteral stone still.stone burden are the main variable of higher re-treatment rate,upper ureteral stone may moving with respiring during eswl.so efficinet shock wave was decreared,re-treatment rate become higher.

目的 评估体外震波碎石治疗输尿管结石的疗效，探讨再治疗率高的原因及输尿管结石的治疗选择。方法回顾2000年1月～2004年12月间eswl治疗输尿管结石的临床资料687例，男455例（66.2%），女232例（33.8%），平均年龄46.6岁（15～83岁）。有双侧输尿管结石6例，单侧多发性输尿管结石12例（4颗1例，3颗2例，2颗9例），共计输尿管结石709颗（含透光结石13颗）。应用上海爱申公司生产的desunit6030型碎石机，c臂x线球管做结石定位。上段输尿管结石（肾盂输尿管交界处至骶髂关节上缘）取仰卧位，下段输尿管结石（骶髂关节上缘下至输尿管口）取俯卧位。为减少eswl引起的肾损伤和疼痛，应用较低的能量，震波发生器电压从9.8～13.2kv，震波频率1.5s。每次治疗设定为1500次震波。治疗后3天摄腹部平片或b超，以后每隔7日重复检查。假如结石未碎或有残留结石最长径＞3mm以上，再次eswl，两次治疗的间隔时间为两周。结石的大小用x线片上的表面积（mm2表示。结果 709颗输尿管结石总的治愈率为97.3%（690颗），再治疗率34.1%（242颗）。其中一次治疗467颗，平均结石大小37.27mm2，治愈464颗（65.4%），3颗改治疗；两次治疗138颗，平均结石大小62.48mm2，治愈131颗（18.5%），7颗改治疗；第1和第2次治疗治愈率（1个月治愈率）为83.8%。3次治疗52颗，平均结石大小79.60mm2，治愈50颗（7.1%），2颗改治疗；4次治疗19颗，平均结石大小101.63mm2，治愈17颗（2.4%），2颗改治疗；5次及5次以上治疗33颗，平均结石大小119.33mm2，治愈28颗（3.9%），5颗改治疗。总计19颗（2.7%）结石改变治疗方式。上段输尿管结石335颗，治愈321颗（95.8%），再治疗129颗（38.5%）。下段输尿管结石374颗，治愈369颗（98.7%），再治疗113颗（30.2%）。经χ2检验，上、下段输尿管结石的再治疗率差异有显著性（χ2=5.40，p＜0.05），治愈率差异无显著性（χ2=0.15，p＞0.05）。不良反应：血压升高13例（1.9%），震波区域疼痛26例（3.8%），震波进入处皮肤点状淤血33例（4.8%），肉眼血尿128例（18.6%），均于第2、3天自行消失。结论 eswl目前仍是输尿管结石的第一线治疗，结石的大小是再治疗率高的主要因素。结石的位置有影响，上段输尿管结石可随呼吸移动，有效震波次数减少，再治疗率比下段输尿管结石高。eswl前注重病例筛选可降低再治疗率。

As the first basic legal instrument that the European Communities have ever adopted as secondary legislation, Regulation on the law applicable to non-contractual obligations is examined and commented comprehensively and to depth. With regard to Regulation's scope, the paper accentuates the former's wide applicability while forecasts the perplexity Member States may have on the issue of their own independent contracting right in the international arena; on the provisions of the Regulation about the applicable law of torts or delicts, unjust enrichment, negotiorum gestio and culpa in contrahendo, and common provisions, the paper reveals the rationales and ideas implied thereof, while comments critically the relevant loopholes or ambiguities.

以欧共体首次颁布的《非合同义务法律适用条例》（文中简称《2007年罗马二号条例》）的法律结构为基本框架，首先分析该条例的适用范围及其与欧共体其他二级立法和国际公约之间的关系，突出显示其在适用方面的广泛性，同时也指出成员国今后在独立对外缔约权方面将会面临的困惑；然后，通过对该条例关于侵权或过失不法行为、不当得利、无因管理和缔约过失责任的法律适用，当事人的法律选择自由以及相关配套制度的全面系统分析，揭示其隐含的法律原则和价值理念，同时指出其存在的漏洞和模糊之处。

As the first basic legal instrument that the European Communities have ever adopted as secondary legislation,Regulation on the law applicable to non—contractual obligations is examined and commented comprehensively and in depth.With regard to Regulation's scope.the paper accentuates the former's wide applicability while forecasts the perplexity Member States may have on the issue of their own independent contracting right in the international arena;on the provisions of the Regulation about the applicable law of torts or delicts,unjust enrichment,negotiorum gestio and culpa in contrahendo,and common provisions,the paper reveals the rationales and ideas implied thereof,while comments critically the relevant loopholes or ambiguities.

以欧共体首次颁布的《非合同义务法律适用条例》（文中简称《2007年罗马二号条例》）的法律结构为基本框架，首先分析该条例的适用范围及其与欧共体其他二级立法和国际公约之间的关系，突出显示其在适用方面的广泛性，同时也指出成员国今后在独立对外缔约权方面将会面临的困惑；然后，通过对该条例关于侵权或过失不法行为、不当得利、无因管理和缔约过失责任的法律适用，当事人的法律选择自由以及相关配套制度的全面系统分析，揭示其隐含的法律原则和价值理念，同时指出其存在的漏洞和模糊之处。

The paper investigates both block-type pilot linear minimum mean square error algorithm and IEEE802.16 OFDM channel estimation analysis. Simulation results confirm the block-type pilot structure is more suitable for IEEE802.16 system. An optimal pilot setting algorithm, based on space frequency domain, is explored and the pilot chart is presented. The proposed algorithm finds its application in MIMO-OFDM. Simulation results show the algorithm presents a good approximation to the perfect channel state information curve, with about 2dB difference in SNR. The simulation results also demonstrate the algorithm achieves fairly high stability in the environment of fast fading, performance of the proposed algorithm is better that of pilot training channel estimation.3. Taking into account the characteristics of IEEE802.16 OFDM system, OFDM system simulation platform is constructed in Matlab, exploiting simulink as a tool. OFDM modulation and demodulation simulation system are configured on LabVIEW platform. All the system signal processing is simulated, including defining system parameters, designing modulation model, and verifying all the proposed algorithms under different environments, such as white Gaussian noise, multi-path fading, with or without guard interval etc. Bit error performance is evaluated. The research provides valid theoretical basis for practical OFDM system performance evaluation.4. Taking advantage of software radio, the paper designs a hardware platform with both 256-IFFT/FFT and 512-IFFT/FFT OFDM schemes co-existing in one platform. You can predetermine one from the two schemes to carry out almost the same model function with different system performance and parameter setting.5. Referring to IEEE802.16 standard, the paper proposes a design method for generating signals and frames suitable for laboratory investigations implemented in laboratory environment.6. Based on 6701evm digital evaluation card, combined with analogy front-end, the paper designs a DSP software model to deal with baseband signal processing. An overall OFDM scheme, with modulation and demodulation function, is accomplished.

讨论分析了MIMO-OFDM中一种基于空频域的最优导频设置算法，给出了导频图案，通过仿真实验表明，该算法与理想的信道状态信息曲线非常接近，信噪比差距约在2dB左右，并且在快衰落条件下具有较好的稳定性，其性能要优于基于前导训练的信道估计方法。3、根据IEEE802.16OFDM系统特点，论文分别在Matlab中应用Simulink工具构建OFDM系统仿真平台、在LabVIEW平台上实现了OFDM调制解调仿真系统，模拟了整个系统的信号流程，进行了OFDM仿真系统参数的选择和调制模块的仿真设计、论证各算法性能，并根据各种不同的条件：例如高斯噪声、多径衰落、有无保护间隔等，对系统的误码特性进行了评估，为正确评价实际OFDM系统的性能提供了有效的理论依据。4、论文以软件无线电思想作为指导，提出了以256点IFFT／FFT为核心和以512点IFFT／FFT为核心的两种OFDM算法模式并存于同一个硬件平台、且可预选的方案，它们在参数选取和性能指标上有所差异，均实现了相似的模块和功能。5、论文参考IEEE 802.16无线网络标准的参数设置，针对本设计系统的应用环境和系统硬件的性能速率，提出了一种应用于实验室环境的信号结构、帧格式等参数设计。6、论文基于TI公司的6701evm数字评估板卡，结合模拟前端搭建数字中频平台，设计了基带处理的DSP软件模块并进行系统调试，基本实现了一套完整的OFDM调制解调方案。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。