With the introduction of CBDC (Central Bank Digital Currency), concerns about surveillance of personal transactions are rising. This post explores how to prevent "monitored consumption" and protect user privacy in the age of digital currency.     📷 Visual: CBDC Security and Privacy  Balancing Digital Wallets and Privacy Source: Freepik (royalty-free) 1. How Well Can Personal Data Be Protected? Since CBDC allows central banks to access transaction data, privacy concerns are inevitable. However, the following technologies can address this: Pseudonymization: Users are identified with anonymous IDs; real names are only accessed when necessary Tiered Privacy: Small payments can remain anonymous; larger ones require identification     2. The Role of Zero-Knowledge Proof (ZKP) ZKP is a cryptographic method that proves a transaction occurred without revealing its contents. This allows you to validate spendin...

When red rashes, itching, or swelling appear after sun exposure, many people quickly assume they have a sun allergy . However, several other skin conditions mimic similar symptoms, leading to frequent misdiagnoses. Properly identifying the exact cause is essential for receiving the right treatment and preventing long-term complications.     Why Sun Allergy Is Easily Confused Sun allergy (also called photosensitivity) typically causes redness, burning, itching, and raised rashes, especially on areas exposed to sunlight like the neck, arms, and face. However, the same regions are affected by many other conditions with overlapping symptoms. This is why correct diagnosis is critical. Here Are 5 Conditions Often Misinterpreted as Sun Allergy:     1. Seborrheic Dermatitis Symptoms: Flaky, red skin especially around the nose, scalp, eyebrows, and ears. Key Difference: Not triggered by sunlight. Caused by overactive oil glands and yeast ...

Have you ever experienced red patches, itching, or rashes on sun-exposed areas of your skin? While it might seem like general skin sensitivity, it could actually be a photosensitivity reaction caused by certain medications . This post explains which medications can trigger sun allergies, how to verify them, and what precautions you should take when using them.     What is a Photosensitivity Reaction? Photosensitivity is a skin reaction caused by a drug or chemical when it interacts with UV rays. This can lead to inflammation or immune responses when the substance becomes active under sunlight exposure. Common Medications That Can Trigger Sun Allergy Antibiotics: Tetracyclines, Quinolones, Sulfonamides Diuretics: Hydrochlorothiazide, Furosemide NSAIDs: Ibuprofen, Naproxen, Ketoprofen Antidepressants and Psychiatric drugs: Tricyclics, some SSRIs Antifungals and Chemotherapy agents Hormonal agents including birth control pills Even ...

One of the biggest challenges in DIY battery pack assembly is how to safely and securely connect 18650 cells. Most professionals recommend using a spot welder, but not everyone has one at home. So, is it possible to connect cells safely and effectively without a spot welder? In this post, we’ll explore alternative methods that don’t damage the cells and are suitable for small-scale battery building.     Common Alternatives to Spot Welding If you don’t have access to a spot welder, here are three main alternatives you can consider: Soldering: The traditional method using a soldering iron to attach nickel strips or wires directly to the cell terminals. Clamping: Mechanically pressing nickel strips onto the cell using clips, screws, or springs. Battery Holders: Inserting cells into prebuilt plastic cases that include metal contact terminals. Each method has its pros and cons, and the best choice depends on your application, the number of cell...

Refrigerators are appliances we open and close dozens of times each day. Especially during summer, the door sensor plays a vital role in minimizing cold air loss. Recently, some Samsung refrigerator users have reported an issue where the door is slightly open, but no alarm goes off. Is this just a sensor malfunction? Or is it a more fundamental design flaw? In this post, we’ll examine the causes behind Samsung refrigerator door alert failures, how electronic sensors work, and what consumers can do about it.     What Is an Electronic Door Sensor? Most modern refrigerators now come with an electronic door sensor . This usually involves a magnetic strip on the door and a reed switch inside the body, which detects the magnetic field to determine whether the door is open or closed. This type of sensor is easier to manufacture, more cost-efficient, and compatible with digital signal processing. However, electronic sensors can fail to detect when the door i...

A center finder is an incredibly useful tool for marking the exact center of a circular piece, but if you don’t have one, you can make it yourself! In this post, you’ll learn how to create your own DIY V-shaped center finder with high accuracy using low-cost materials.     1. Basic Idea: The 90-Degree V Frame The heart of a DIY center finder is a right-angle (V-shaped) frame with a guide hole at the apex . When this V frame is aligned to the edge of a circle and a line is drawn through the apex, multiple lines from different angles will intersect at the true center. 2. Materials Needed MDF or plywood (3–5mm thick recommended) Saw or laser cutter Set square or precision triangle Screws or wood glue Pencil or scribe     3. How to Build It Cut two right triangles out of MDF or plywood. Join them to form a perfect 90-degree V-shaped frame. Drill a small hole at the apex where the two arms meet. This is w...

Lithium-ion batteries power our daily devices—smartphones, laptops, electric vehicles, and more. But when you need to store these batteries for months or years, improper storage can lead to performance loss, reduced lifespan, and safety hazards. This guide shares practical tips to help you store lithium-ion batteries for 6 months to 1 year (or longer) while keeping them in great condition.     Ideal Charge Level for Storage Storing batteries at 100% charge or fully discharged (0%) accelerates chemical degradation and reduces lifespan. The best charge level for long-term storage is between 40% and 60%. This reduces internal stress on electrodes and helps prevent deep discharge from natural self-discharge over time. Temperature and Environment High temperatures accelerate electrolyte degradation, while extreme cold reduces chemical activity. The ideal storage environment is a cool, dry place between 10°C and 25°C . Avoid storing batteries in places like car...