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Elisabetta Bugianesi, MD, PhD, who was not involved in the study, agrees that nonalcoholic fatty liver disease in particular is an important clinical entity that can be difficult to identify."NAFLD constitutes a special challenge for physicians for several reasons: any distinction between nonprogressive and progressive disease is only based on liver histology, but NAFLD patients are generally asymptomatic invasive procedures are not easy to propose to accept," she told Medscape via email.

未参与此项研究的Elisabetta Bugianesi医师同意非酒精性脂肪肝病是重要的临床表徵，但是却不易鉴别诊断；她以电子邮件向Medscape表示，NAFLD对医师们构成一个特别的挑战，因为在非进行性和进行性的疾病之间的差别，仅可从肝脏组织判断，但是NAFLD病患一般是没有症状的，所以对於侵入式的诊断方式难以接受。

Some of the neuroeconomics topics we are studying at Caltech include: Why people find it difficult to attach dollar prices to goods that are not traded (like environmental harm, health, and safety); whether having too many choices actually makes people less happy with what they own; thinking strategically about what other people will do, when you are trying to outguess them or cooperate with them; how people behave when they fear economic unknowns (like starting small business or investing in countries with unstable political systems); deception in bargaining; the neural foundations of intrinsic motivation for working hard, like intellectual curiosity; and moods and investor sentiment in stock markets.

目前我们在加州理工学院从事神经经济学研究的课题项目包括：为什麽人们认为给不能用以交换的商品(如环境损害、健康、安全)定价格是困难的；面对太多的选择是否使人们竟然对自己拥有的现状感觉不甚愉快；当你试图智算他人或与他人合作时，从策略上考虑他们将做什麽；当人们担忧经济不可预测时（如：开创小企业，或投资于政治体系不稳定的国家），他们将采取什麽样的行为；讨价还价的骗术；努力工作的内在动机的神经基础；心态和投资者对股票市场的情绪，等等。

As a result, for feed-forward NN model this paper first proposes the concepts of"attractor"and"attraction region","fake attractor"and"fake attraction region", and norm of describing"attraction region". Further this paper presents a mathematics method of calculating feed-forward NN"attraction region", it solves the overelaborate job of checking NN fault-tolerance performance by testing all detecting samples, so to test fault-tolerance performance using theoretic characteristic norm is an important break. In accordance with feed-forward NN low fault-tolerance and difficult to satisfy practical application, according to practical application theory, this paper presents an actual method of enhancing NN fault-tolerance performance, builds the mechanism of reconstructing NN model based on combining NN and fuzzy process, reforms NN "fake attractor"and"fake attraction region"to enhance NN fault-tolerance performance greatly.

为此，本文首先给出了前馈NN模型的&吸引子&和&吸引域&，&伪吸引子&和&伪吸引域&的定义，以及描述吸引域的指标，在此基础上提出了一种计算前馈NN模型&吸引域&大小的数学计算方法，该方法提出解决了目前依靠对检测样本的测试工作来检验NN容错性的繁琐工作，而用具理论意义的性能指标来检验，这是一个重要的突破；针对前馈NN容错性较低以致难于满足实用的缺点，根据NN实用稳定性理论，提出了一种提高其容错性的实用方法，建立了基于NN与模糊处理相结合的NN模型重构机制，重构NN&伪吸引子&和&伪吸引域&来大大地提高NN的容错性。

Today, the products are manufactured according to ergonomics and artistic. So, engineers usually design an object with exquisite shapes. Before the products are manufactured, they will be segment to several parts with machinability. Those parts usually have the feature of free-form surface. However, it is difficult to determine whether those parts are partible or not.

现今的产品，为了人体工学、视觉美观的因素，常设计了相当精巧的曲线，所以切割出来的零件常具有复杂曲面的特徵，这些复杂曲面通常造成了判断零件的可脱模性上，相当大的困扰，在模具设计的流程中将会增加相当多的时间。

The faciform ligament is an important sign of laparoscopic liver surgery and a way of collateral circulation of liver. The superior liver artery found and named in this research can be an important sign to judge the position of hepatic vein. The operation pathway by cutting down the perihepatic ligament next to the superior border of liver is a quick way with little blood. It is difficult to hurt diaphragm and hepatic vein, and the secundum porta hepatic can be showed clearly. As a rule, we break the hepatic vein in the hepatic parenchyma on laparoscopic hepatectomy. But in some situation, extrahepatic treatment was used.

镰状韧带是腹腔镜肝脏外科入路的重要标志，是肝脏侧枝循环的重要途径；本文所发现并命名的肝上动脉可以作为判定肝静脉位置的重要标志；紧贴肝上缘打开肝周韧带，不易损伤膈肌和肝静脉，出血少、速度快，可以使第二肝门获得良好的手术显露；腹腔镜肝切除时一般在肝实质内切断肝静脉，在个别情况也可以预先在第二肝门结扎切断肝静脉。

Since the Pipa is the most difficult to excel, that's why I chose to learn it and it pushes my perseverence to the limit.

因为琵琶是最难以成为卓越者的乐器，这也是我为什么选择学习它的原因，也是我毅力的极限。

Some of these solutions are not difficult to implement and we really have a very serious responsibility to the women of the world to stop them from dying, preventively.

其中一些措施并不难执行，我们必须行动，去防止孕产妇的死亡。

Because I just have associate degree ,so it is very difficult to promotion .so I want reback to the school make a better diploma, inorder to the better development in the future.

所以我想到学校里进修一个更好的文凭。以便日后更好的发展。

But in practical operating, overvoltage caused by reignition of the vacuum switching device frequently appears, and it result in damage of the capacitor bank or the switchgear itself. Ensuring the switchgear against reignition and installing a protective device are two main approaches to avoid the phenomenon. In this paper, a study on overvoltage caused by reignition due to capacitor bank switching with the vacuum switching device and its preventive measures are carried out. The main work which has been done and researches are as follows: 1. The producing mechanism of overvoltage and its influence factor are analyzed. It is pointed out that single-phase reignition is the main reason for damage of the switchgear and two-phase reignition is the main reason for damage of the capacitor bank,so overvoltage of single-phase reignition and two-phase reignition are the emphases of prevention. 2. Analysis of the special working condition of the operating switch for capacitor bank is carried out. It indicates that the vacuum switching device is difficult to realize no-reignition under this operation condition, so it is more practical to adopt protection devices. 3. Analyses of protection effect of RC and MOA and their shortages are carried out. It shows that the two methods can only restrain effectively overvoltage caused by single-phase reignition, and they cannot protect the capacitor bank when reignition of two-phase occurs. 4. The operation principle of G-R damping device is analyzed and discussed emphatically.

本文针对真空开关投切电容器组时因重燃而产生的过电压及其防治措施进行了研究，所开展的主要工作和研究结果如下： 1、对过电压的产生机理及其影响因素进行了分析，指出单相重燃是导致开关设备损坏的主要原因，而两相重燃则是导致电容器组损坏的主要原因，因此单相重燃和两相重燃过电压是防护的重点； 2、对电容器组操作开关的特殊运行条件进行了分析，指出在这种运行条件真空开关难于实现不重燃，因此采用保护装置更具有现实意义； 3、对RC与MOA的保护效果和存在的不足进行了分析，指出这两种方法均只能有效抑制单相重燃过电压，而不能在发生两相重燃时保护电容器组； 4、重点对G-R阻尼装置的工作原理进行了分析和讨论，指出该装置接入后线路中将会出现两种频率的高频振荡，而电容器组上的过电压是由这两种振荡共同决定的； 5、根据对上述两种振荡的分析指出存在一个最佳电阻值使得过电压最低，并提出了电容器组电压和最佳电阻值的近似求解方法； 6、使用电气暂态分析软件MATLAB对G-R装置的保护效果进行了仿真计算，证实该装置确实可以有效抑制重燃时的电容器组过电压； 7、根据仿真与近似计算结果的偏差提出了近似计算的修正方法，经过修正后的过电压计算结果与仿真结果吻合较好； 8、对G-R装置中放电装置G与阻尼电阻R的要求进行了分析，指出采用编织电阻和真空间隙可能是最佳选择。

Head lice are difficult to remove because of their size, reinfestation rate, life cycle, and their ability to develop immunity to insecticides.

头虱是很难去除，因为它们的大小， reinfestation率，生命周期，其开发能力的免疫力杀虫剂。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷