标签：#compute

Forget about patchy internet connections and dead spots in the house. These WIRED-tested multiroom mesh systems will get you online in no time.

On June 9th, Anthropic released its Fable generative AI model. Three days later, the US government classified it as a dangerous munition, and used its export-control authority to prohibit any foreign nationals from accessing it. Unable to differentiate between Americans and foreigners, the company shut off access for everyone. The government’s actions won’t help . The problem isn’t any one particular model; it’s the general trend of increasing AI capabilities. And any real solution requires the sort of collective action that just isn’t possible right now...

Elsewhere, beyond-classical quantum hardware, plus classical computing fires back.

I’ve been reviewing laptops for over a decade, and this is my advice on how to find the right laptop for you.

Microsoft has finally refreshed its premium Surface Laptop and Surface Pro with new chips, but the update comes with a steep price hike.

🚀 Hello, DEV Community! I'm Nader Al Shawki , a final-year AI Engineering student at Al-Razi University, Yemen. This is my first post here, and I'm excited to start sharing my journey with this amazing community. 🎯 Who Am I? I'm passionate about building production-grade AI systems that solve real-world problems. My main areas of focus are: 🖼️ Computer Vision & Deep Learning 🤖 ML Model Deployment (Docker, FastAPI, REST APIs) 🧠 LLMs, RAG, and AI Agents (currently learning) 📊 Data Visualization & Analytics (Power BI) 💡 What I've Built So Far 1. 🍅 Tomato Leaf Disease Detection Platform Tech: YOLOv8, PyTorch, FastAPI, Docker What it does: Detects tomato leaf diseases from images with real-time inference. Containerized with Docker for easy deployment. 2. 🫁 Pneumonia Detection System Tech: PyTorch, CNN Architecture, Medical Imaging What it does: A deep learning model that detects pneumonia from chest X-ray images. 3. 📊 Sales Profit Analysis Dashboard Tech: Power BI, DAX, Data Analysis What it does: Interactive dashboard for tracking sales KPIs. 4. 😀 Face Detection & Emotion Recognition Tech: OpenCV, Deep Learning What it does: Real-time face detection, age estimation, emotion recognition, and gender classification. 5. 🍽️ Restaurant Website Tech: HTML5, CSS3, JavaScript What it does: Fully responsive restaurant website with interactive UI. 🌱 What I'm Currently Learning LLMs (Large Language Models) RAG (Retrieval-Augmented Generation) LangChain & AI Agents Workflow automation with n8n 🔗 Let's Connect 🐙 GitHub: Naderalshawki 💼 LinkedIn: in/nader-al-shawky 📫 Email: naderalshawki@gmail.com Thanks for reading! I'll be posting regularly about AI projects, tutorials, and lessons learned. Stay tuned! 🚀

I've been going through Jim Kurose's networking lectures lately, and I kept finding myself pausing to re-read the same sections. Not because they were confusing - because things I'd been using for years were finally clicking into place. This post is me writing down what I learned, in the order it started making sense. Before HTTP, there's a webpage A webpage isn't one file. When you open a URL, your browser fetches a base HTML file - and that file references other objects. Images. Scripts. Stylesheets. Each one lives at its own URL. Each one has to be fetched separately. So loading a single "page" might mean firing off 20+ individual requests. This detail matters because the entire evolution of HTTP - from 1.0 to 3 - is basically the story of making those 20 fetches faster. HTTP runs on TCP. That has consequences. HTTP doesn't manage its own connections. It hands that job to TCP. When your browser wants something, it first opens a TCP connection to the server (port 80 for HTTP, 443 for HTTPS), and then asks for the object. Opening a TCP connection isn't free. It takes a round-trip - your machine says "hello," the server says "hello back," and then you can actually talk. That's one RTT(Round Trip Time) just to shake hands, before a single byte of your webpage arrives. So every HTTP request carries at least 2 RTTs of overhead: 1 to open the TCP connection, 1 for the actual request/response. Do that 20 times and you've spent 40 RTTs before the page renders. HTTP/1.0 vs HTTP/1.1: one change that mattered a lot HTTP/1.0 (non-persistent): open a TCP connection, fetch one object, close the connection. Repeat for every object. HTTP/1.1 (persistent): open a TCP connection, fetch as many objects as you need, then close. The server leaves the connection open after each response. That one change cuts subsequent fetches from 2 RTTs to 1 RTT each. For a page with 20 objects, that's real time saved - not microseconds, but hundreds of milliseconds that users actually feel. What an

[Excerpted from THE QUANTUM COLLAPSE CHRONICLES — not science fiction, but a grounded forecast of what may come when quantum computation dismantles the cryptographic foundations of our digital civilization. These articles explore the collapse of computational trust and the brutal reconstruction of the world that follows.] The history of human civilization is often defined by sudden, violent shifts in the nature of power. We speak of the fall of empires, the industrial revolutions, and the splitting of the atom. But in the mid-2030s, the world experienced a collapse that was not made of steel or stone, but of mathematics. It was a quiet, clinical, and utterly devastating unraveling of the digital fabric that held modern society together. To understand The Quantum Collapse , one must look past the headlines of the era and into the humming, sub-Kelvin depths of the dilution refrigerators that changed everything. This is the story of how the transition from probabilistic experimentation to deterministic computation rendered the world's secrets transparent and its economies obsolete. The Death of Noise: The Rise of Dr. Aris Thorne For the first three decades of the 21st century, quantum computing was a game of chance. Scientists operated in the era of Noisy Intermediate-Scale Quantum (NISQ) devices—machines so temperamental and prone to error that every calculation was a desperate struggle against environmental noise. In those days, a single stray photon or a microscopic fluctuation in temperature could collapse a delicate superposition, turning a groundbreaking calculation into useless digital static. The turning point arrived in 2036 at the Institute for Advanced Quantum Engineering (IAQE) in the High Sierras. The air in the facility didn't vibrate with the erratic drone of the late 2020s; instead, it carried a heavy, rhythmic thrum—the sonic signature of the Lattice-Array-9 (LA-9). At the center of this revolution was Dr. Aris Thorne, the lead architect of the LA-9 pr

Network Protocols Network protocols define how computers communicate over a network. Whether you're opening Instagram, sending a WhatsApp message, watching Netflix, or transferring money through a banking app, some protocol is working behind the scenes to make communication possible. Client-Server Model What is it? The Client-Server model is a communication architecture where: Client requests a service or data. Server processes the request and returns a response. Most modern applications follow this architecture. How Does It Work? Client ---------- Request ----------> Server Client <--------- Response ---------- Server The client always initiates communication, and the server listens for incoming requests. Real World Example Instagram When you open Instagram: Mobile app sends a request. Instagram servers process the request. Feed data is fetched from databases. Posts are returned to your phone. Instagram App | V Instagram Server | V Database Advantages Centralized control Easier security management Easy maintenance Easier data consistency Disadvantages Server can become a bottleneck Single point of failure if not replicated Interview One-Liner Client-Server architecture is a centralized model where clients request resources and servers provide them. Peer-to-Peer (P2P) Model What is it? In a Peer-to-Peer network, every machine can act as both: Client Server There is no central server controlling communication. How Does It Work? Peer A <------> Peer B ^ ^ | | V V Peer C <------> Peer D Each peer can directly share resources with others. Real World Example BitTorrent Instead of downloading a file from one server: User | +--> Peer 1 | +--> Peer 2 | +--> Peer 3 Different parts of the file are downloaded from multiple peers simultaneously. Blockchain Bitcoin and Ethereum networks operate using Peer-to-Peer communication. Advantages Highly scalable No central server cost Better fault tolerance Disadvantages Harder to manage Security challenges Data consistency issues Inter

If you're someone who needs to (or likes to) take their work on the go, a portable monitor will make a huge difference. These are my favorite that I tested.

Every hand-tracking demo shows you 21 dots. The interesting part is what nobody shows: turning dots into numbers someone can act on. Dots are a capability, not a product Run any modern hand-tracking model and you get 21 beautifully stable landmarks per hand at 30 FPS. Impressive — and by itself, worthless. No client has ever paid for dots. They pay for measurements : is this clearance compliant, is this part aligned, did this patient's range of motion improve. I learned this on utility infrastructure work, where the deliverable was never "we detected the wire" — it was the attachment height of that wire, and whether it violates clearance rules . Keypoints were step one of three. The demo: live metrics, not just a skeleton My portfolio's keypoint demo derives three measurements per hand, every frame: const wrist = lm [ 0 ]; const palm = distance ( wrist , lm [ 9 ]); // scale reference const pinch = distance ( lm [ 4 ], lm [ 8 ]) / palm ; // thumb tip ↔ index tip The crucial line is the scale reference . Pixel distances are meaningless — they change as you move toward the camera. Dividing by palm length (wrist to middle knuckle) gives a relative measurement that's stable under distance, and multiplying by the average adult palm length (~8.5 cm) converts it into an approximate real-world gap — the demo shows "≈ 3.2 cm" floating on the pinch line. In infrastructure work the same role is played by a known object dimension — a standard crossarm, a pole class height. Every measurement-from-pixels system needs its ruler. Finger counting is a geometric test (is each fingertip farther from the wrist than its middle joint?), and "hand openness" averages fingertip extension — three lines of geometry each, but they convert a model output into a readout a human understands instantly. Honest layering The landmarks come from MediaPipe's pretrained pipeline (palm detector → landmark regressor → gesture classifier, float16, WASM + GPU delegate) — Google's models, credited on the page

Camouflage has always been graded by human eyes. But the thing hunting for you in 2026 is increasingly a detection model — so test against that. The premise Surveillance is automated now: drones, trail cameras, perimeter systems — most of what "sees" runs an object-detection network. Which makes traditional camouflage evaluation (a person squinting at a photo) the wrong test. The right test is adversarial: run the actual detector against your concealment and measure what it finds. That's the whole demo: upload a photo, and an object-detection model hunts for people in it — at four simulated distances — producing a detection-range profile and a stealth score. Simulating distance with pixels You can't move the camera after the photo is taken, but you can simulate the dominant factor in long-range detection: pixels on target . A person at 50 m simply occupies far fewer pixels than at 5 m. So each analysis run downscales the image progressively and re-runs detection: const DISTANCE_LEVELS = [ { label : ' Close (~5m) ' , scale : 1 }, { label : ' Mid (~15m) ' , scale : 0.45 }, { label : ' Far (~30m) ' , scale : 0.22 }, { label : ' Very far (~50m) ' , scale : 0.12 }, ]; for ( const level of DISTANCE_LEVELS ) { const scaled = drawScaled ( image , level . scale ); const detections = await model . detect ( scaled , 10 , 0.15 ); // best 'person' confidence at this simulated range } The output reads like a range card: detected at 5 m with 96% confidence, 41% at 15 m, invisible beyond 30 m. A stealth score aggregates it: how poorly did the adversary see you, averaged across ranges? Honest about the model The detector is COCO-SSD (a pretrained MobileNet-based model from the TensorFlow.js team) running entirely on-device — I didn't train it, and the demo says so on the page. The contribution here is the evaluation framework : using detectors as adversaries, simulating range, and turning subjective "good camo" into a measurable profile. The full version of this concept goes further

A 1990s Nobel-adjacent therapy, a webcam, and 21 hand keypoints — recreating the mirror-box illusion for phantom limb pain, no hardware required. A therapy built on an illusion In the 1990s, neuroscientist V.S. Ramachandran discovered something remarkable: amputees suffering phantom limb pain often felt relief just by seeing their missing limb move again. His apparatus was almost comically simple — a box with a mirror. Put your intact hand in, look at its reflection where the missing hand would be, and move. The brain, watching the "missing" hand obey commands again, often dials the pain down. The limitation was never the science. It was the box: a physical apparatus, used in clinics, hard to scale, impossible to measure. Replacing glass with keypoints A webcam plus real-time hand tracking can produce the same illusion with better properties: webcam frame → hand landmark model (21 keypoints, on-device) → reflect: phantom[i] = { x: 1 − x, y, z } → render real hand (solid) + phantom twin (ghost) on canvas The reflection is one line of math. Everything around it is what makes the illusion land: const phantom = real . map ( p => ({ x : 1 - p . x , y : p . y , z : p . z })); The visual treatment matters more than I expected. The phantom hand is rendered as a ghostly cyan skeleton with a translucent palm fill, a "breathing" glow that pulses on a ~3 second cycle, and a fading afterimage trail of its last few frames — it reads as present but ethereal , which is exactly the perceptual story mirror therapy needs to tell. A dashed mirror plane down the center of the frame makes the reflection relationship legible at a glance. The engineering details that matter Tracking : MediaPipe HandLandmarker (Google's pretrained model — credit where due), running via WebAssembly with GPU delegate. ~30 FPS on a laptop. Privacy by architecture : every frame is processed on-device. For a medical-adjacent application, "video never leaves your browser" isn't a feature, it's a requirement. Lazy

Laptops for college should be portable, offer long battery life, and remain reasonably affordable. Based on testing hundreds of laptops, these are my top picks.

Problem Link - https://leetcode.com/problems/delete-node-in-a-linked-list/ This is one of those interview questions that looks impossible at first. Normally, to delete a node from a Linked List, we need access to the previous node. But in this problem, we're only given the node that needs to be deleted. No head. No previous pointer. So how do we remove it? Let's understand the trick. Problem Statement Write a function to delete a node in a singly linked list. You are not given the head of the list. Instead, you are given only the node that needs to be deleted. Example Input: 4 -> 5 -> 1 -> 9 node = 5 Output: 4 -> 1 -> 9 Initial Thought Normally we delete a node like this: prev.next = node.next But here: We don't have prev We don't have head So the usual deletion approach is impossible. Key Observation Although we cannot delete the current node directly, we can make it look like it never existed. Consider: 4 -> 5 -> 1 -> 9 We need to delete: 5 Instead of removing node 5 , copy the value of the next node into it. 4 -> 1 -> 1 -> 9 Now remove the next node. 4 -> 1 -> 9 The original value 5 has disappeared. Mission accomplished. Intuition Copy the next node's value into the current node. Skip the next node. The current node now behaves as if it was deleted. Since the problem guarantees that the given node is not the tail node, a next node will always exist. Dry Run Input 4 -> 5 -> 1 -> 9 node = 5 Current node: 5 Next node: 1 Step 1 Copy next node value. node.val = node.next.val List becomes: 4 -> 1 -> 1 -> 9 Step 2 Skip next node. node.next = node.next.next List becomes: 4 -> 1 -> 9 Done. Optimal Java Solution class Solution { public void deleteNode ( ListNode node ) { ListNode cur = node . next ; node . val = cur . val ; node . next = cur . next ; } } Even Shorter Version class Solution { public void deleteNode ( ListNode node ) { node . val = node . next . val ; node . next = node . next . next ; } } Complexity Analysis Metric Complexity Time Complexity O(1) Space Comp

Earlier parts examined the performance characteristics of sequential and random access under single-threaded execution, and noted in passing the destructive effect of random access on the TLB. This part devotes full attention to the TLB: what it is, why a TLB miss is more severe than a cache miss, why a page table walk constitutes one of the longest dependency chains a CPU can encounter, how huge pages fundamentally alter TLB reach, and where memory-level parallelism falters in the face of TLB misses. Page Boundaries: Where the Prefetcher Halts Part III, in its discussion of prefetchers, noted a hard constraint: a prefetcher must not cross page boundaries on its own authority. The operating system manages virtual memory in units of pages (typically 4 KB, i.e., 64 cache lines). When a program reaches the end of one page and is about to step into the next, the prefetcher cannot proceed. The reason is that the next page may not reside in physical memory (it may have been swapped out to disk), or it may be an entirely invalid virtual address — if the prefetcher were to speculatively initiate an access to the next page, it would trigger a page fault: the OS would have to suspend the process and swap the page in from disk; in the case of an invalid address, the OS would terminate the process outright. From a security standpoint, the prefetcher neither can nor is permitted to autonomously cross page boundaries without TLB approval. Hence a performance brake appears every 4 KB — even when traversing an array sequentially, after every 64 cache line accesses the prefetch pipeline must pause and await confirmation of an address translation. This is not to say that modern CPU prefetchers are completely unable to cross pages. Intel's Next Page Prefetcher and AMD's equivalent mechanism can consult the TLB when approaching a page boundary — if the address mapping for the next page is already registered in the TLB, the prefetcher receives clearance to continue prefetching across th

Apple has announced the latest version of macOS. It’s all about the reintroduction of Siri, which is now accessible from anywhere on the Mac desktop.

Have you ever wondered how Discord keeps your channel messages available even when a server goes down? Or how Amazon DynamoDB serves petabytes of data with single-digit millisecond latency? The unsung hero powering almost all these distributed systems is hashing — a simple but powerful technique that makes even load distribution, fast lookups, and seamless scaling possible. As more applications move to distributed cloud architectures, understanding hashing for distributed systems is no longer optional for developers. Choosing the wrong hashing algorithm can lead to cascading failures, cache stampedes, and expensive downtime. This guide breaks down every core hashing technique, real-world use cases, best practices, and common pitfalls to avoid in 2026. Table of Contents What is Hashing in Distributed Systems? Core Hashing Algorithms Explained Traditional Modulo Hashing Consistent Hashing Virtual Nodes (VNodes) Rendezvous Hashing (HRW) Jump Consistent Hash Maglev Hashing Multi-Probe Consistent Hashing Consistent Hashing with Bounded Loads Real-World Applications of Distributed Hashing Head-to-Head Algorithm Comparison Best Practices for Distributed Hashing Common Pitfalls to Avoid Conclusion References What is Hashing in Distributed Systems? Hashing in distributed systems is the practice of mapping data keys (e.g., user IDs, object keys, channel IDs) to server nodes using a deterministic hash function. The core goals are: Distribute load evenly across all nodes to avoid hotspots Enable fast lookups (O(1) or O(log N)) without a central coordinator Minimize data movement when nodes are added or removed during scaling Support fault tolerance by simplifying replication across nodes The simplest implementation is modulo-based hashing , where node_id = hash(key) % N and N is the total number of nodes. While trivial to implement, it suffers from a fatal flaw: the rehashing problem. When N changes (a node is added or removed), nearly all keys are remapped to new nodes, causin

Lenovo's IdeaPad Slim 5x just might be the best laptop you can buy for $850. It's hard to find any major flaws, which is basically unheard of in a laptop at this price.

If you're a networking instructor — at a university, technical college, boot camp, or corporate training program — you know the frustration of teaching the OSI Model. Static PowerPoint slides can only do so much. Students nod along in class, but when exam time arrives, the layers blur together. The PDU names become a confusing jumble. The OSI Model Simulator by Roboticela was built with educators in mind. It transforms a passive lecture into an interactive demonstration that students engage with, remember, and take home to explore on their own. Classroom Use Cases Live Demonstration Project the simulator on a classroom screen. Have students suggest messages to send and protocols to use. Step through each layer together as a class, stopping to ask questions: "What's happening here? What header was added? What device would operate at this layer?" The interactive format maintains attention far better than any lecture. Lab Assignments Assign students to run specific simulations and document their findings: "Run HTTP and HTTPS simulations. Screenshot the Presentation Layer for each. Explain in writing what differs and why." This assignment tests both tool usage and conceptual understanding. Flipped Classroom Send students to app.osi-model-simulator.roboticela.com before class. Ask them to run three simulations and come prepared to discuss what they observed. Class time becomes richer discussion rather than basic concept delivery. Protocol Comparison Exercise Have students run simulations for all five protocols — HTTP, HTTPS, SMTP, DNS, FTP — and create a comparison chart noting the differences at each OSI layer. This develops deep protocol literacy that traditional instruction rarely achieves. Why It Works: The Science of Active Learning Research in educational psychology consistently shows that active learning produces dramatically better retention than passive instruction. The "Learning Pyramid" (Edgar Dale's Cone of Experience) suggests: Lecture: ~5% retention after 2