查询词典 upper boundary

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。

Paleozoic stratum can be separated east and west stratigraphical areas, according to lithological character and palaeontological information, contacted relationships and diversification of stratigraphical units in horizontal and vertical etc. The stratums in west area can be divided Devonian-Carboniferous Nanduan formation and Permian Laba formation, which is passive continental margin-bathyal depositional sequences comprised argillaceous and detrital rocks, small siliceous and carbonatite in upper. The stratums in east area can be divided lower-middle Devonian Wenquan formation and middle-upper Devonian Manxin formation, upper Devonian-lower Carboniferous Pingzhang formation, Carboniferous-Permian Yutangzhai formation, middle Permian Damingshan formation, upper Permian Shifodong formation respectively, moreover, middle-upper Permian Huoju formation is exposed in Menglian area.

根据地层的岩石组合、古生物、接触关系和地层单位的纵横向变化等特征，晚古生代的地层明显的可分为东、西两个地层小区：东部地层小区从下至上可划为泥盆—石炭系南段组、二叠系拉巴组，为一套泥质岩、碎屑岩，上部夹硅质岩、碳酸盐岩建造，属被动大陆边缘斜坡—半深海沉积；西部地层小区由下至上划分为下—中泥盆统温泉组、中—上泥盆统曼信组、上泥盆—下石炭统平掌组、石炭—二叠系鱼塘寨组、中二叠统大名山组、上二叠统石佛洞组，此外，在孟连一带尚出露中—上二叠统火居组。

Based on varying process of generator terminal parameters after excitation fault, shortages of excitation protective principle of static stability boundary and asynchronous impedance boundary are analyzed. It proposed that excitation fault research relates to large-disturbance stability. Because dynamic power-angle character of generator after excitation fault is non-sinusoidal, there are differences between dynamic power-angle character and static state power-angle character. So it isn't ideal to protective operation result based on small-disturbance stability and static stability boundary criterion. At the same time, it proposed that asynchronous boundary impedance criterion is a constant reactive power circle moving adown j Xd′. It can ensure complete loss-of-excitation generator measuring impedance enter into the circle, but can't ensure the other condition measuring impedance including impossible losing synchronism enter. So loss-of-excitation protection would be maloperation when system voltage drops short and recovers or generator rejects load.③Based on stability principle, it puts forward setting conditions and calculation method of generator loss-of-excitation protection by direct measuring power-angle.

以励磁故障后发电机端的相关参数的变化为基础，通过对以静稳定边界和异步阻抗边界作判据的两类三种现行励磁保护在原理上存在的缺陷分析，发现：励磁故障是一个大干扰稳定性问题，励磁故障后的发电机的动态功角特性与静态功角特性有很大的差异，已远非正弦曲线，因此基于小干扰稳定性原理、以静稳定边界作判据的保护必然动作不理想；异步边界阻抗判据是一个下移j Xd′的等无功阻抗圆，它可以保证完全失磁后的发电机测量阻抗能进入该阻抗圆，但不能保证完全失磁之外的其它状态不会进入该阻抗圆，因此在系统电压短时下降或发电机突然甩负荷等情况下可能启动该保护使之误动。

The results show that the absorbing effect of low-order Higdon absorbing boundary condition is undesirable and relatively strong boundary reflection exists in wave field snapshot and analog recording; the effect of traditional and improved PML absorbing boundary conditions are similar, which can effectively absorb and attenuate the boundary reflections from any angle.

结果表明，低阶Higdon吸收边界条件吸收效果较差，在波场快照和模拟记录中存在较强的边界反射；改进的PML吸收边界条件与传统的PML吸收边界条件效果相当，均能有效地吸收衰减任意角度的边界反射波。

Taking electrostatic field as an example problem, based on the general analytical series solution of electrostatic field,(1) the zero, first and second order asymptotic boundary conditions on circular truncation boundary; and (2) the zero and first order asymptotic boundary conditions on arbitrary polygonal truncation boundary are derived.

有限元法计算无界电磁场问题是电磁场数值分析中的一个重要课题，在这里计算精度与计算量之间的矛盾尤为突出。

Based on the boundary integral formula and natural boundary integral equation for the boundary value problems of biharmonic equation , the non-symmetrical banding solutions to the circular plate under thermal boundary conditions are gained by the Fourier series and convolution formulae.

根据双调和方程边值问题的边界积分公式和自然边界积分方程，利用傅立叶级数及卷积的几个公式，求得了相应变温边界条件下非对称载荷圆板的弯曲解，从实践上证明了此方法的可行性。

We have also presented the ω-circulant boundary condition and compared it with the helix boundary condition. Furthermore, we can also get another new boundary condition: the mixed boundary condition.

由此我们提出了ω循环型边界条件并将其与普通循环型及螺旋型边界条件作了分析和比较；进一步地，得到了一种新的边界条件：混合型边界条件。

In view of geological records preserved from different regions of the world are not identical, it's suggested that, when correlating the Ordovician-Silurian boundary, at the global boundary stratotype section, the FAD of N. persculptus be selected as the biomark, the transgression event identical to the FAD of N. persculptus as the auxiliary physical mark and the mass extinction and chemical anomaly events respectively as the auxiliary biomark and chemomark. In some regions with few graptolite, the Ordovician-Silurian boundary should be indicated by the auxiliary marks, such as the transgression event, mass extinction or chemical anomaly event, with the other fossil such as conodont nearest to other geological events as the provincial biomark for correlation. In other regions with much stratigraphic hiatus originated from the regression, the Ordovician-Silurian boundary should be marked by the regression-transgression event nearly relevant to the N. persculptus Zone.

鉴于不同地区留下的地质记录不完全相同，奥陶/志留系界线对比方法不同：在界线层型剖面上，以N.persculptus的首现为生物标志，以与之基本一致的海侵事件为辅助的物理标志，以生物集群绝灭事件和化学异常事件为辅助的生物和化学标志；在笔石极不发育的地区，则以海侵事件、生物绝灭事件或化学异常事件为辅助标志，以与其相距最近、并且具有区域对比性的其它门类化石作为界线对比的生物标志；对于由于海退事件所造成地层缺失很多的地区，则以海退/海侵事件作为划分界线的物理标志，并以相映的海侵事件的开始作为奥陶/志留系的分界。

Two problems were solved in numerical calculation, one was that a term of 1/r in Maxwell was divergence in cylindrical center where r=0, another was that the value of optical field at cylindrical center was difficult to decided when the cylindrical center set as a boundary condition in Maxwell equation, So the values of optical field need just calculate from cylindrical center to cylindrical boundary, comparing from cylindrical boundary to cylindrical boundary, near upon half CPU time and RAM saved.

计算中解决了在圆柱中心线上Maxwell方程存在发散项1/r以及用圆柱中心线作为边界条件时，中心线上光场值难确定的问题，因而光场只需从圆柱中心计算到圆柱边界，和以圆柱的两条边做为边界条件比较，节省了将近一半的计算时间和计算机存储空间。

The author compares the effects of Dirichlet boundary condition and attenuation one on artificial boundary with that on transmitting boundary, so does the absorption effects, the author also demonstrates the advantage of transmitting boundary.

文中还就刚性边界条件、衰减边界条件对人工边界的影响及吸收效果与透射边界作了对比，验证了透射边界的优越性。

Panorama Many people are dancing in a large sitting room.

在一个大客厅里，许多人在跳舞。

We fully understand how a microwave oven cooks food, it is first necessary to talk ...

我们充分理解一个微波炉煮的食物，这是首先要谈。。。