N
negative inventory- An error condition resulting from a transaction that drives the perpetual inventory below zero. Systems that allow negative inventory usually provide exception reports for cycle counting and analysis, and specify how the negative is handled in modules such as MPS and MRP.
Nelson tests- A set of quality tests measuring trend, lack of variation and observation of consecutive results of the same values.
nervous- A planning system such as MRP that generates high message volume and continual changes to recommended order dates and quantities due to an excessive level of MPS, engineering or database changes.
nested- A process or activity self-contained within a larger entity, that retains its identity and characteristics for reporting and analysis.
net assets- Total assets less total liabilities.
net cash flow- Cash inflow (sales revenue) less cash outflow (payments).
net change- An MRP or other planning system generation that only recalculates requirements for items that have changed since the last generation, due to the addition or changes in order quantities and dates, inventory levels, bill of material or routings, lead times or other parameters. A flag is usually set by programs that initiate changes for those items, which is used by MRP as the basis to regenerate them. It typically reduces generation time and is most useful for companies that have many part numbers, a small percentage of which are active in a given week.
net requirements- The requirements for an item based on its gross requirements (from forecasts, customer orders or upper level demand), minus stock already on-hand and scheduled receipts. If the total is below the specified safety stock, a planned order is generated based on the lot size. The generation of a new planned order for a given net requirement is normally done only after calculating the effect of rescheduling all incoming receipts to the dates required.
net sales- Gross sales less allowances for returns and discounts.
netting- Deducting requirements (orders, allocations, planned run hours, etc.) from an available resource (inventory, work center capacity, etc.).
network diagram- The depiction of a system in terms of individual points (which may represent a location, resource, status or task) and the links between them used to pass goods, services, data or other communications. It helps model the relationships of the links and the timing and direction of the flows between them.
node- 1) An individual point within a network that represents a separate entity and is linked to other nodes within the overall system. In a supply chain, individual companies and locations can be considered nodes. 2) A decision point in a decision tree.
noise- The difference between the predicted and observed values of a model due to random error including missing and incomplete data.
nominal data- Data described by a value that assigns it to a category, but does not provide for a ranking or ordering of the values.
nominal range- The distance that a system that transmits signals, such as a network or RFID device, can reliably complete transmission.
nonconformance- The status of a process or product that does not meet specification and requires attention or corrective action.
nondestructive testing- A quality conformance test that does not eliminate the future usage of the product or service being tested.
non-inventoried item- Normally, a supply item purchased and received but whose on-hand quantity is not calculated.
nonlinear- A product or process that exhibits an uneven distribution, or wide variations in terms of quantity and timing.
nonrecurring- An event or cost not considered to be part of normal, ongoing business operations that is separated or filtered out when forecasting future events or reporting financial information.
non-significant part number- A part number composed of characters that do not imply anything about the characteristics of the part or the family it belongs to. Separate code and description fields are used to convey associated information instead of building it into the part number itself.
non-stationary demand- A pattern in which demand is not constant for each time frame but varies due to seasonality, trend or other factors.
non value-added- Activities and costs that can be eliminated without reducing performance, function or value as perceived by the customer.
normal distribution- The frequency of a data distribution simulating a bell-shaped curve that is symmetrical around the mean and exhibits an equal chance of a data point being above or below the mean. (syn: Gaussian distribution).
normalized data- Data that has been adjusted or reduced to eliminate redundancies and anomalies.
not earlier than- Specification that a project task, shipment or delivery may not occur before a given date. Early product shipments are normally considered as a negative in evaluating delivery performance due to customer storage space or payment considerations.
not later than- Specification that a project task, shipment or delivery may not occur after a given date, due to its effect on a later task or the inability to use a late shipment in production or for a specific sales promotion.
np chart- A measurement of the number of nonconforming values in a constant or fixed sample size.
numerical control (NC)- A machine tool that uses machine-readable sets of numeric codes that control the activities used in its operation.