الإطار الكامل لمعايير الأجهزة الطبية

The Finite Volume Method (FVM) is a dominant numerical technique in CFD for solving partial differential equations. It discretizes the domain into a mesh of control volumes and applies the governing equations in their integral form to each volume. By converting volume integrals to surface integrals using the divergence theorem, it focuses on calculating the flux of conserved properties across cell faces.

Verification and validation (V&V) are distinct processes. Verification ensures a product meets its specified requirements ("Are you building it right?"). Validation ensures the product meets the user's actual needs and intended use ("Are you building the right thing?"). They are complementary activities within quality management, often performed sequentially or in parallel to ensure both correctness and usefulness.

The repeatability limit, \(r\), is a critical value derived from the repeatability standard deviation (\(s_r\)). It represents the maximum expected absolute difference between two single test results, obtained under repeatability conditions, with a 95% probability. It is commonly calculated as \(r = 2.8 \times s_r\). If the difference exceeds \(r\), the results are considered suspect.

Total Quality Management (TQM) is a management philosophy where all members of an organization participate in improving processes, products, services, and the culture in which they work. It aims for long-term success through customer satisfaction. TQM integrates quality-discipline into the culture and activities of a company, moving beyond simple product inspection to a holistic, organization-wide approach.

Lithium-ion batteries function via an intercalation mechanism, a reversible insertion of ions into a layered host material. During discharge, lithium ions (\(Li^+\)) de-intercalate from a negative electrode (anode), typically graphite, and move through a non-aqueous electrolyte to intercalate into a positive electrode (cathode), typically a metal oxide. Electrons travel through the external circuit, creating current.

5S is a workplace organization method that uses a list of five Japanese words: Seiri (Sort), Seiton (Set in Order), Seisō (Shine), Seiketsu (Standardize), and Shitsuke (Sustain). This system aims to improve efficiency and eliminate waste by organizing a workspace for effectiveness. It is a foundational component of Kaizen and lean manufacturing, creating the stable environment necessary for improvement.

Relationship marketing is a strategic approach that shifts the focus from individual transactions to building long-term customer loyalty and engagement. It emphasizes customer retention, satisfaction, and lifetime value over short-term sales goals. Key tactics include customer relationship management (CRM) systems, loyalty programs, and personalized communication, aiming to create a strong, emotional connection between the brand and the customer.

Molecular electronics explores using individual molecules or nanoscale molecular collections as fundamental electronic components. This approach aims to build circuits at the ultimate limit of miniaturization, far beyond traditional silicon-based technology. Key components include molecular wires, switches, and rectifiers, leveraging quantum mechanical properties like electron tunneling through molecular orbitals for their function.

A design methodology where 'X' represents a specific product life cycle objective. DFX encompasses a collection of guidelines and techniques aimed at optimizing a product's design for a particular goal, such as manufacturability (DFM), assembly (DFA), reliability (DFR), or sustainability (DfS). This proactive approach addresses potential issues early in the design phase, reducing costs and improving quality.

Formal verification is the use of mathematical methods to prove or disprove the correctness of a system's design with respect to a formal specification. Unlike testing, which can only show the presence of bugs for specific inputs, formal verification can prove their absence for all possible inputs. It involves creating a formal model of the system and using techniques like model checking or theorem proving.

Physics of Failure (PoF) is a reliability engineering approach that uses knowledge of materials science and physics to understand and model the root-cause mechanisms of failure. Instead of relying purely on statistical data from past failures, it focuses on predicting failure by analyzing the physical processes (e.g., fatigue, corrosion, creep) that lead to degradation and breakdown.

To address the inability of different CAD systems to share data, neutral file formats were created. The Initial Graphics Exchange Specification (IGES), developed in the late 1970s, was an early attempt. It was later superseded by the more robust and comprehensive STEP (Standard for the Exchange of Product model data, ISO 10303), which can represent full 3D models, assembly structure, and metadata.

Kaizen is a Japanese term meaning "change for the better" or "continuous improvement." It is a core philosophy of lean manufacturing that focuses on making small, ongoing, positive changes to improve processes and eliminate waste. Kaizen involves all employees, from senior management to assembly line workers, fostering a culture where everyone is empowered to suggest and implement improvements.

Successful Takt time implementation requires a highly stable production environment. Common challenges include managing machine downtime, ensuring consistent quality to avoid rework, and balancing lines that produce multiple products with different work contents (mixed-model lines). Without addressing these sources of variability, a Takt-driven system can be brittle and fail to meet demand consistently.

A Single-Electron Transistor (SET) is a switching device that uses controlled electron tunneling to manipulate the flow of single electrons. It consists of a quantum dot (the 'island') coupled to source and drain leads via tunnel junctions, and capacitively coupled to a gate electrode. Its operation relies on the Coulomb blockade effect, enabling extreme sensitivity and low power consumption.