特點(diǎn)(FEATURES) 精確度0.1%滿刻度 (Accuracy 0.1%F.S.) 可作各式數(shù)學(xué)演算式功能如:A+B/A-B/AxB/A/B/A&B(Hi or Lo)/|A| (Math functioA+B/A-B/AxB/A/B/A&B(Hi&Lo)/|A|/etc.....) 16 BIT 類比輸出功能(16 bit DAC isolating analog output function) 輸入/輸出1/輸出2絕緣耐壓2仟伏特/1分鐘(Dielectric strength 2KVac/1min. (input/output1/output2/power)) 寬范圍交直流兩用電源設(shè)計(jì)(Wide input range for auxiliary power) 尺寸小,穩(wěn)定性高(Dimension small and High stability)
數(shù)字運(yùn)算,判斷一個數(shù)是否接近素?cái)?shù)
A Niven number is a number such that the sum of its digits divides itself. For example, 111 is a Niven number because the sum of its digits is 3, which divides 111. We can also specify a number in another base b, and a number in base b is a Niven number if the sum of its digits divides its value.
Given b (2 <= b <= 10) and a number in base b, determine whether it is a Niven number or not.
Input
Each line of input contains the base b, followed by a string of digits representing a positive integer in that base. There are no leading zeroes. The input is terminated by a line consisting of 0 alone.
Output
For each case, print "yes" on a line if the given number is a Niven number, and "no" otherwise.
Sample Input
10 111
2 110
10 123
6 1000
8 2314
0
Sample Output
yes
yes
no
yes
no
We have a group of N items (represented by integers from 1 to N), and we know that there is some total order defined for these items. You may assume that no two elements will be equal (for all a, b: a<b or b<a). However, it is expensive to compare two items. Your task is to make a number of comparisons, and then output the sorted order. The cost of determining if a < b is given by the bth integer of element a of costs (space delimited), which is the same as the ath integer of element b. Naturally, you will be judged on the total cost of the comparisons you make before outputting the sorted order. If your order is incorrect, you will receive a 0. Otherwise, your score will be opt/cost, where opt is the best cost anyone has achieved and cost is the total cost of the comparisons you make (so your score for a test case will be between 0 and 1). Your score for the problem will simply be the sum of your scores for the individual test cases.
為了提高直接轉(zhuǎn)矩控制(DTC)系統(tǒng)定子磁鏈估計(jì)精度,降低電流、電壓測量的隨機(jī)誤差,提出了一種基于擴(kuò)展卡爾曼濾波(EKF)實(shí)現(xiàn)異步電機(jī)轉(zhuǎn)子位置和速度估計(jì)的方法。擴(kuò)展卡爾曼濾波器是建立在基于旋轉(zhuǎn)坐標(biāo)系下由定子電流、電壓、轉(zhuǎn)子轉(zhuǎn)速和其它電機(jī)參量所構(gòu)成的電機(jī)模型上,將定子電流、定子磁鏈、轉(zhuǎn)速和轉(zhuǎn)子角位置作為狀態(tài)變量,定子電壓為輸入變量,定子電流為輸出變量,通過對磁鏈和轉(zhuǎn)速的閉環(huán)控制提高定子磁鏈的估計(jì)精度,實(shí)現(xiàn)了異步電機(jī)的無速度傳感器直接轉(zhuǎn)矩控制策略,仿真結(jié)果驗(yàn)證了該方法的可行性,提高了直接轉(zhuǎn)矩的控制性能。
Abstract:
In order to improve the Direct Torque Control(DTC) system of stator flux estimation accuracy and reduce the current, voltage measurement of random error, a novel method to estimate the speed and rotor position of asynchronous motor based on extended Kalman filter was introduced. EKF was based on d-p axis motor and other motor parameters (state vector: stator current, stator flux linkage, rotor angular speed and position; input: stator voltage; output: staror current). EKF was designed for stator flux and rotor speed estimation in close-loop control. It can improve the estimated accuracy of stator flux. It is possible to estimate the speed and rotor position and implement asynchronous motor drives without position and speed sensors. The simulation results show it is efficient and improves the control performance.