Disclosure of Invention
The invention aims to provide a laboratory ventilation abnormity detection method and system capable of detecting whether a ventilation pipeline is abnormal.
The invention provides a laboratory ventilation abnormity detection method, which comprises the steps of S1, S2 and S3, wherein the step S1 is to collect real-time wind speed data in a ventilation pipeline in real time; step S2 is to collect the real-time wind speed data, and construct an anomaly recognition model from a plurality of wind speed data over a period of time; step S3 is to detect the real-time wind speed data by a mathematical statistic method according to the abnormality recognition model and determine whether the ventilation duct is abnormal.
Further, in step S1, multiple sets of real-time wind speed data are collected simultaneously in the ventilation duct.
Further, the step S2 includes S21 and S22, the step S21 is to build a time sliding window model for the real-time wind speed data, and the step S22 is to build the abnormality recognition model for a plurality of sliding window data in the time sliding window model.
Further, the step S21 includes steps S211 and S212, the step S211 is to form the real-time wind speed data into sequence data according to the collection time, the step S212 is to maintain a window with a constant size for the sequence data, store the latest data, when new data comes, the oldest data will expire, the window will store the latest data and remove the oldest data, and form the time sliding window model.
Further, the step S22 includes steps S221 and S222, where the step S221 is to filter out median med in the sliding window data, and the step S222 is to construct the anomaly identification model by using the lazida criterion and using med ± 3 σ as an interval, where σ is a standard deviation in the sliding window data.
Further, in the step S1, multiple sets of real-time wind speed data are collected simultaneously in the ventilation duct; the step S3 includes steps S31 and S32, the step S31 is to determine whether the real-time wind speed data is abnormal according to the abnormality recognition model by using the mathematical statistics method, the step S32 is executed when the abnormality occurs, and the step S32 is to determine that the ventilation duct is abnormal when more than half of the plurality of sets of real-time wind speed data are abnormal.
Further, in the step S31, the method for determining whether the real-time wind speed data is abnormal is that if any data in the sliding window data is not within the med ± 3 σ interval, it is determined that the real-time wind speed data is abnormal.
Further, in the step S31, the method for determining whether the real-time wind speed data is abnormal is that two adjacent data in the sliding window data are equal, and it is determined that the real-time wind speed data is abnormal.
The invention also provides a laboratory ventilation abnormity detection system which comprises a plurality of wind speed sensors, a sensing network and a background server and is used for realizing the laboratory ventilation abnormity detection method.
Further, the background server is used for sending alarm information when the ventilation pipeline is abnormal.
The laboratory ventilation abnormity detection method and the laboratory ventilation abnormity detection system provided by the invention utilize a mathematical statistics method to establish an abnormity identification model to detect the ventilation condition of the laboratory, and the method is simple and easy to implement. And time sequence data is processed through a sliding window model, and a plurality of groups of detection data are simultaneously analyzed, so that errors caused by individual reasons generated by too small data quantity or damage of a single data acquisition point are avoided. If the abnormity is detected, the abnormity information is pushed in time, the danger caused by the ventilation fault is avoided, and the safety of the laboratory is improved.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Referring to fig. 1 to 3, a method for detecting abnormal ventilation in a laboratory according to an embodiment of the present invention includes the following steps:
s1: collecting real-time wind speed data in the ventilation pipeline 10 in real time;
s2: collecting real-time wind speed data, and constructing a plurality of wind speed data in a period of time into an abnormal recognition model;
s3: and detecting real-time wind speed data by using a mathematical statistical method according to the abnormality identification model and judging whether the ventilation duct 10 is abnormal or not.
Referring to fig. 1, in step S1, wind speed data collection points are disposed at multiple positions in the ventilation duct 10, so as to avoid the influence of data deviation on the detection result caused by instrument damage and the like at a single data collection point. In other embodiments, the positions of the specific wind speed data acquisition points can be adjusted according to actual conditions, but the number of the wind speed data acquisition points is as large as possible, so that the deviation caused by too small data quantity is avoided.
Step S2 includes S21: respectively establishing a time sliding window model and S22 for a plurality of groups of real-time wind speed data: and constructing an abnormal recognition model for the sliding window data in the time sliding window model. Step S21 includes S211: forming the real-time wind speed data into sequence data according to the acquisition time; s212: maintaining a window with constant size for the sequence data, storing a plurality of latest data, wherein when new data arrives, the oldest data is expired, and the window stores the latest data and removes the oldest data to form a time sliding window model. For example, the window size is k, the latest k data are saved, and the current window data are assumed to be
When new data is present
When the data arrives and is normal data, the window changes, and the data in the window is updated to be normal data
The subsequent data is analogized.
Step S22 includes S221: screening out median med in the sliding window data; s222: and constructing the anomaly identification model by adopting a Laplace criterion and using med +/-3 sigma as an interval. The general control chart method is based on the average value X of the control chart, but X is easily affected by extreme values and anomalies tend to appear as extreme values, so the control chart is built by using the median med of the data set. For example
As sensor node S
jData sets within a T period.
In other embodiments, if the number of window data k is large enough, the sliding window data can be regarded as approximately normal distribution, and the situation can be madeBy mean value
The Laviand criterion is applied for the midline.
The lazida standard has intervals med ± c σ of 68%, 95%, and 99.7%, where c ═ 1,2,3 }. In the interval formed by med ± 3 σ, the probability that the measured value does not belong to this interval is 0.3%. As shown in fig. 3, the model consists of three lines: the centerline (ML, Middle line), which is the median of the sensor node data set, and the upper Control line (UCL, UpperControl Limit) and Lower Control line (LCL, Lower Control Limit). By sigmamedRepresenting the standard deviation of the sensor node data set. In specific use, in order to make the data more approximate to a normal distribution and avoid errors, the value of the window data k should be increased as much as possible.
ML=med (2)
UCL=med+3σmed(3)
LCL=med-3σmed(4)
Step S3 includes S31 and S32, and step S31 is performed by determining whether there is an abnormality in the real-time wind speed data according to the abnormality recognition model using a mathematical statistics method, and performing S32 when the abnormality occurs. In step S31, the method for determining whether the real-time wind speed data is abnormal is to determine that the real-time wind speed data is abnormal if any of the sliding window data is not within the interval. I.e. if
If equation (5) is not satisfied, the wind speed data is abnormal data:
wherein ucl and lcl are the upper and lower limits of the control chart model interval respectively,
sampled at time i when
And (5) updating the data of the window.
Meanwhile, in step S31, if two adjacent data in the sliding window data are equal, it is also determined that the real-time wind speed data is abnormal. Since when a wind speed sensor fails, it is possible to produce the same readings in successive sampling instants, i.e.
In step S32, when more than half of the real-time wind speed data sets are abnormal, it is determined that the ventilation duct 10 is abnormal.
The method provided by the embodiment detects the ventilation condition of the laboratory by using mathematical statistics, processes time sequence data through the sliding window model, and constructs the abnormality recognition model. And a plurality of groups of detection data are simultaneously analyzed, so that errors caused by individual reasons generated by too small data quantity or damage of a single data acquisition point are avoided.
Referring to fig. 2, the present embodiment further provides a laboratory ventilation anomaly detection system 20, which includes a plurality of wind speed sensors 21, a sensor network 22 and a background server 23, and is used to implement the laboratory ventilation anomaly detection method. The wind speed sensor 21 is disposed in the ventilation duct 10, and the wind speed sensor 21 is connected to the background server 23 through the sensing network 22, so as to send the collected real-time wind speed data to the background server 23 through the sensing network 22. The background server 23 is configured to construct an anomaly identification model to detect the real-time wind speed data and determine whether the ventilation duct 10 is anomalous, and send alarm information when it is determined that the ventilation duct 10 is anomalous.
The method and the system for detecting the ventilation abnormity of the laboratory utilize a mathematical statistics method to establish an abnormity identification model to detect the ventilation condition of the laboratory, and the method is simple and easy to implement. And time sequence data is processed through a sliding window model, and a plurality of groups of detection data are simultaneously analyzed, so that errors caused by individual reasons generated by too small data quantity or damage of a single data acquisition point are avoided. If the abnormity is detected, the abnormity information is pushed in time, the danger caused by the ventilation fault is avoided, and the safety of the laboratory is improved.
In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. It will be understood that when an element such as a layer, region or substrate is referred to as being "formed on," "disposed on" or "located on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly formed on" or "directly disposed on" another element, there are no intervening elements present.
In this document, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms can be understood in a specific case to those of ordinary skill in the art.
As used herein, the meaning of "a plurality" or "a plurality" is two or more unless otherwise specified.
As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, including not only those elements listed, but also other elements not expressly listed.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.