例句與用法

1. Because the fundamental frequency of power system is not invariable , it needs to be tracked and measured
   由于電網(wǎng)的基波頻率并非始終不變的，因此需要對實(shí)際的電網(wǎng)頻率進(jìn)行跟蹤檢測。
2. This problem could be resolved by using sub - harmonic mixer ( shm ) . instead of using mmw lo , shm using microwave signal with frequency equals 1 / 2 or 1 / 4 of mmw lo frequency , thus the technical difficulty and cost of mmw system is reduced remarkably
   采用亞諧波混頻器( sub - harmonicmixer )可將本振頻率降為基波頻率的1 / 2或1 / 4 ,從而克服了直接采用毫米波本振源帶來的困難,降低了射頻接收機(jī)的技術(shù)難度和系統(tǒng)成本。
3. A new harmonic analysis method for electric power systems based on triangle basis functions neural network was presented , the convergence theorem of the algorithm was proposed , and a window function and interpolation algorithm were employed to correct the frequency of fundamental waves
   摘要提出了一種新的基于三角基函數(shù)神經(jīng)網(wǎng)絡(luò)的電力系統(tǒng)諧波測量方法，給出了該神經(jīng)網(wǎng)絡(luò)算法的收斂定理，并采用加窗插值算法修正基波頻率的準(zhǔn)確度。
4. According to the characters of the power harmonic , a kind of self - adaptive harmonic detection method based on in - phase correlation filtering is presented , which is clear and concise in thinking . by this method the low - pass filter can be designed easily , and by using the multiresolution and self - adaptive technique the difficulties of harmonic detection with low variable fundamental frequency and no voltage reference are worked out , which contributes much to the implementation of harmonic suppression
   該方法思路清晰、簡潔，并能方便有源濾波器( apf )中低通濾波器設(shè)計，同時采用多分辨率和自適應(yīng)濾波方法，解決了基波頻率低且變化、無明顯電壓基準(zhǔn)可尋的復(fù)雜供電系統(tǒng)諧波檢測的難題，為諧波抑制的實(shí)施奠定了基礎(chǔ)。
5. A patch antenna with etched holes on the ground plane is also studied . the performance of the antenna at the resonant frequency is analyzed by using the fdtd method together with the pml boundary treatment . the results show that the surface waves are suppressed greatly , the bandwidth is improved and a 1 odb reduction on the sidelobe level is achieved at the 110 and 260 directions in the e plane
   全面地研究了地面腐蝕周期圓孔結(jié)構(gòu)的電磁晶體貼片天線在基波頻率處的性能，用fdtd方法并結(jié)合pml邊界處理技術(shù)對該天線所取得的研究結(jié)果顯示，本文設(shè)計的地面腐蝕型電磁晶體結(jié)構(gòu)抑制了貼片天線中的表面波，增加了天線的帶寬，并有效地削弱了旁瓣，使天線的e面方向圖上110和260方向的兩個旁瓣被削弱了10db 。