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How to store in computer? Two’s Complement 0000 0000 is 0 0000 0001 is 1 0000 0010 is 2 0111 1110 is 126 1000 0000 is -128 1000 0001 is -127 1000 0010 is -126 1111 1110 is -2 1111 1111 is -1 -x equals reverse all bits then +1. Floating Point In IEEE 754, 32 bit: 1-bit s for ± 8-bit E for power 23-bit M for number after dot +/−0.1M×2E+/-0.1M\times2^E+/−0.1M×2E Character Set ASCII 1 byte UTF-8 1~4 byte Unicode usually 2 byte. Instruction Set CISC RISC Exception Control Reasons internal ...

Intelligent Computing System is a combination of Deep Learning, Parallel Programming, Computer Organization and Computer Architecture. Neural Network Basis Loss function L(w)=12∑i(H(xi)−yi)2=12∑i(wTx−yi)L(w)=\frac{1}{2}\sum_i(H(x_i)-y_i)^2=\frac{1}{2}\sum_i(w^Tx-y_i)L(w)=21​∑i​(H(xi​)−yi​)2=21​∑i​(wTx−yi​) Gradient Descent: w=w−α∂L(w)∂ww=w-\alpha\frac{\partial L(w)}{\partial w}w=w−α∂w∂L(w)​ Activate Function Back Propagation: Chain Rule ∂L∂w=∂W∂y∂y∂z∂z∂w\frac{\partial L}{\partial w}=\frac{\part ...

Cryptology DES Designed by IBM. Use a 56-bit key to encrypt and decrypt 64-bit blocks of data. Process: 64-bit msg and 56-bit key as input Perform a permutation on the key to generate 16 48-bit subkeys, each of which will be used in one of the 16 rounds of encryption. divide plaintext into 2 32-bit blocks initialize the left block L0 to be the first 32 bits of the plaintext and the right block R0 to be the second 32 bits. Perform 16 rounds of encryption, in each round: Perform an expansion o ...

Web Development Front End HTML, CSS, JavaScript, JQuery… HTTP request get, post, put, delete request. Back End High level language + SQL XAMPP, WordPress Yii2 framework(PHP) Database Design Web Security csrf xss SQL injection

Network Abstract ISO-OSI Model Physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer TCP-IP Architecture link layer, internet layer, transport layer, application layer Ethernet topology: bus or star. CSMA/CD listen before sending, listen while sending, stop when afflict, delay then resend. Wireless Network 802.11 AP IBSS CSMA/CA CA aka conflict avoid. RTS CTS IP Protocol IPv4 IPv6 ICMP Broadcast address: 255.255.255.255 ...

Signal Sampling: sensor→A/D Digital signal VS analog signal analog: both X Y are contiguous. digital: both are discrete. Basic Operations on Digital Signal x[n]={⋯ ,−0.2,2.2,1.1,0.2,−3.7,⋯ }x[n]=\{\cdots,-0.2,2.2,1.1,0.2,-3.7,\cdots\}x[n]={⋯,−0.2,2.2,1.1,0.2,−3.7,⋯} addition, multiplication, time shifting(delay), reversing(反折), stretching(拉伸) difference(差分): x′[n]=x[n+1]−x[n]x'[n]=x[n+1]-x[n]x′[n]=x[n+1]−x[n] accumulation(累加) ⚠️Convolution(卷积​，非常重要): F(t)=x(n)∗h(n)=∑kx[n−k]h[k]F(t)=x(n) ...

Lagrange Interpolation 拉格朗日插值 Pn(x)=∑i=1nyi(Πj≠i1≤j≤nx−xjxi−xj)P_n(x)=\sum_{i=1}^ny_i(\Pi_{j\neq i}^{1\leq j\leq n}\frac{x-x_j}{x_i-x_j})Pn​(x)=∑i=1n​yi​(Πj=i1≤j≤n​xi​−xj​x−xj​​) Using polynomials to approximate the original function. Residuals R(x)=f(x)−p(x)=f(n+1)(ξ)(n+1)!ω(x)R(x)=f(x)-p(x)=\frac{f^{(n+1)}(\xi)}{(n+1)!}\omega(x)R(x)=f(x)−p(x)=(n+1)!f(n+1)(ξ)​ω(x), ξ∈(a,b)\xi\in(a,b)ξ∈(a,b) relies on x. Newton Interpolation Difference Quotient aka 差商 f[xi,xi+1]=f(xi+1)−f(xi)xi+1−xif[x_i,x_ ...

Logic and Reasoning details in Introduction to AI. Modern Algebra Magma magma 代数系统 Binary operation assume S is a set mapping f: S×S→SS\times S\rightarrow SS×S→S is a dyadic operation on S. dyadic operation 二元运算: The result of the dyadic operation is still belong to S. Every element in S can participate in the dyadic operation and get a unique result. e.g. In the natural number set N addition and multiplication are binary operators on N, but subtraction and division are not. Quasigroup ...

Data Structure List 1234list1 = ['physics', 'chemistry', 1997, 2000]list2 = [1, 2, 3, 4, 5, 6, 7 ]print ("list1[0]: ", list1[0])print ("list2[1:5]: ", list2[1:5]) Tuple similar to List, but the element in tuple can’t be changed 1234tup1 = ('physics', 'chemistry', 1997, 2000)tup2 = (1, 2, 3, 4, 5, 6, 7 )print ("tup1[0]: ", tup1[0])print ("tup2[1:5]: ", tup2[1:5]) Dictionary { key : value } 123dict = {'Na ...

Number System Decimal, binary, octal, hexadecimal (how to transfer) Logic Operation and or not nand(与非) nor(或非) xor(异或) Boolean Function Y=AB‾+A‾B+B‾C‾+ACY=A\overline B+\overline AB+\overline B\overline C+ACY=AB+AB+BC+AC Karnaugh Map simplify the Boolean function. A\BC 00 01 11 10 0 1 1 1 1 1 1 1 Adjacent 2 ‘1’ can be merged result is not only. both A‾C‾+AB‾+BC\overline A\overline C+A\overline B+BCAC+AB+BC and A‾B+AC+B‾C‾\overline AB+AC+\overline B\overline CAB+AC+BC are correc ...