高频

When palaeoclimate became arid, the content of authigenic carbonate increased, and the proportion of aeolian silty sand in terrigenous clast increased distinctly too.

在高频旋回中，当气候偏干旱时，页岩中的自生碳酸盐含量增加，同时风成粉砂在陆源碎屑中所占的比例也明显升高。

Secondly, 4 methods of azimuth estimation based on vector hydrophone according to forms of nosie and signal are brought forward. The principles of these 4methods are set forth, simulating them by computer. Acoustic intensity averager can effectively suppress isotropic non-coherent interference; DOA based on line-spectra can effectively detect the target radiating line-spectra and estimate its azimuth angle; Bar graph approach can suppress line-spectra coherent interference and distinguish different targets radiating line-spectrum. Weighted bargraph approach can detect target in broadband coherent interference and estimate its azimuth angle.

其次，根据背景干扰和信号样式的不同，提出了单矢量水听器方位估计的4种方法；阐述了这4种方法的原理，并进行了计算机仿真，指出平均声强器方位估计适用于各向同性噪声场背景干扰，讨论了平均声强器的处理增益；目标辐射噪声中有线谱时，线谱方位估计有很好的性能，其中的LOFAR线谱和高频解调得到的DEMON线谱都是目标的特征谱线，可以利用它们进行方位估计，详细讨论了利用特征线谱单个矢量水听器分辨多目标的性能；直方图方位估计能抗强线谱相干干扰；加权直方图方位估计可以抗宽带相干干扰。

Bachel degree above, majing in Electronics, with over 2 years related wk experience; over 1 year wk experience in EMC design of board /card products; familiar with EMC testing stards the technical requirements of EMC EMS testing items; familiar with theetical knowledge in analog circuit, digital circuit, high-frequency electronic circuit, signal system electromagnetic field.

电子类专业本科以上学历，2年以上相关工作经验，有1年以上板卡类产品EMC设计工作经验，了解EMC测试标准，熟悉EMC，EMS的各项测试项目的技术要求，熟悉模拟电路，数字电路，高频电子线路，信号与系统，电磁场的理论知识。

Based on the model,the relationship between the main pulse frequency of supply power and the balanceable inter-electrode gap is discussed.

给出了脉冲电化学加工极间平衡间隙的数学模型，并据此讨论了高频群脉冲电化学加工中，电源主脉冲频率与平衡加工间隙的关系。

The adaptor is a must for numerous computer peripherals. As an important computer exporter worldwide, the dc power supply industry is bloomy in Taiwan. In today's dc power supply market, the switch power supply has replaced the linear adaptor as main stream in the industry globally for its compact size. However, SPS has a serious problem of high frequency electromagnetic interference and causes harmonic feedback for the AC power source compared with linear adaptor. The energy consumption is also worse for SPS than linear adaptor.

摘要整流器是许多电脑周边设备不可或缺的电能，而台湾又是电脑及周边产品出口大宗国，因此电源供应器产业澎勃发展是必然的，其中轻薄短小及输出稳定之交换式电源供应器(Switch Power Supply：SPS)，已取代传统线性整流器的地位，成为外销主力并取得世界龙头地位，然SPS有严重的高频电磁干扰问题(150KHz~300MHz)，在交流电源侧产生的谐波含量，也较线性整流器来得严重，为一耗能产品。

The physical model and simulation mathematical model for high-frequency floating new structure caseless and common structure auto-rifle are established separately in this dissertation when they are in conditions with or without restrain, the simulation model sets are constructed and some simulation models are tested by the comparison with theoretical value to test value.

本文分别建立了无约束和有约束条件下高频浮动新结构无壳弹枪和常规结构自动步枪的物理模型和仿真数学模型，它们构成了&仿真模型集&，通过理论值和实验值的比较，对部分仿真模型进行了验证。

In this paper, using multi rigid dynamics, by considering the match motion of the shooter s body, the automatic motion, floating and the rifle, a launch dynamic model is established for caseless rifle .

采用多刚体系统动力学理论，考虑人体、自动机、浮动体与全枪的耦合运动及自动机循环各阶段的运动与碰撞，建立了高频浮动新结构无壳弹枪在卧姿有依托状态下的发射模型，通过数值模拟，得出三发点射状态下无壳弹枪的发射特性，并与常规自动步枪作了比较，分析了无壳弹枪性能的优越之

It has beenfound that different profiles of mobility are celative to different time-dependencesof gate capacitance.

指出用稳态高频栅电容C_g~*-V_g关系求得的是表观载流子浓度分布n~*和表观迁移率分布μ~*。

On the basis of previously research, this paper re-probe into the mechanism of electro-chemist mechanical manufacturing process, making the rational technological parameter, and developing the manufacturing equipment. Through a lot of technology tests, get a lot of labratory data, accordingly, researched the surface feature of the electro-chemist manufacturing process, and deeply discussed its influence on the work piece feature. The last result is that: the electro-chemist mechanical manufacturing process can reduce the low-frequency component significantly, but on high-frequency component, it has little influence, having obviously positive pole flat effect. After manufacture, the tip parts on the surface of the work piece is cut off, there is micro "high land" shape, the parameter for surface roughness is reduced a lot, the surface outline of the work piece is negative, the bearing length rate is cliffy. Also the surface quality of the work piece is improved. This can help to avoid changing the shape, improve the feature of rub, gear and reduce the time to suit. This would also ensure the precision and result in a longer work piece life.

在以前研究的基础上，本论文重新探讨了电化学机械复合光整加工工艺的机理，确定了较合理的工艺参数，对电化学机械复合光整加工设备进行了改进，通过工艺实验广泛地搜集了大量实验数据，依据实验数据，多角度地研究了电化学机械复合光整加工的表面形貌特点，并且从理论上深入讨论了电化学机械复合光整加工表面形貌对工件工作性能的影响，最后得出的结论为：电化学机械复合光整加工对工件原始表面的低频成分有较大程度的降低，而对高频成分影响较小，有明显的阳极整平作用，被加工工件表面的尖峰状凸起被去除，工件表面呈现出微观&高原型&，表面轮廓不平度高度特性参数大幅度降低，工件表面轮廓分布集中，且呈负偏态，轮廓偏斜度为负值，轮廓支承长度率曲线陡峭，工件的表面质量得到综合改善，这对提高零件的抗接触变形能力、改善摩擦、磨损性能、降低工件的磨合时间、提高工件的精度保持性、延长工件的寿命均有利。

After take analyzed deeply for the opened magnet circuit with FEMM (Finite Element Method Magnetics) we find out the field distributing that is separated into three sections . One is the main area what we called as positive field section. Beside the main field there are tow areas that are called the inverted field sections. Loudspeaker arise a very serious distortion when the voice coil moving into inverted field areas. The direction of induced current in the coil part of entered inverted field area is same with the current driving into loudspeaker so that total currents increas largely and heat increase rapidly. With more coils moving into inverted area the voice coil will take on negative inductance properties. It is the main reason that voice coil is burned by heating with increasing current due to arise negative inductance. So opened magnetic circuit is not suitable for the woofers in which the voice coil have wider displacement range. When using this kind magnetic circuit design, the voice coil moving range should be less than the range of positive field to avoid loudspeaker arise serious distortion and heating. Even though voice coil moving range is in the positive area, loudspeaker will still arise more distortion because the field distribution is very cliffy at tow sides of the positive area and full range of magnetic field distribution is not parallel that will arise distortion. Base on above reasons, opened magnetic circuit is not an ideal magnetic circuit for low-frequency loudspeakers. But it can be used in mid-range or high-frequency productions.

开式磁路是由2片钕铁硼磁铁和主导磁板和导磁垫片组成，我们在实践过程中发现这种磁路结构不适合于低频扬声器的使用，我们通过使用FEMM（Finite Element Method Magnetics）软件包对该磁路进行了分析，该磁路的磁场范围被分成3个区域，其中在主导磁板附近形成一个正向磁场，在正向磁场的两边存在反向的磁场，音圈在工作时有很大一部分进入了反向磁场中，在反向磁场内线圈的感应电流方向与驱动电流方向相同，使得音圈呈现出负感抗特性，由于音圈的负感抗特性引起电流的增加导致音圈发热甚至烧毁，因此在扬声器中使用开式磁路时，音圈的运动范围应控制在正向磁场范围之内，否则音圈运动到反向磁场区域时将会产生很大的失真和发热，即使在设计时已经将音圈的运动范围控制在正向磁场范围之内，由于正向磁场的2个边缘磁场强度衰减太快，同时开式磁路中磁场的分布不是平行的，而是自由发散的分布，这样肯定会导致扬声器的非线性失真，因此我们得到的结论是：开式磁路并不是一个理想的磁路，它不适合于低频扬声器的使用，但它还可以应用于中高频扬声器。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！