Claims:1. A system for identifying at least one physical and/or non-physical characteristics of at least article from plurality of said articles, said system comprising:
at least one maker device to receive said articles for processing;
at least one interfacing means operably coupled to said maker device, to sense at least one speed of said article and generate at least one speed signal;
at least one image capturing means, to receive at least one image of said article and thereby communicate said image to an image processing device, wherein said image processing device comprises:
at least one data storing means, to pre-store at least one first information corresponding to said physical and/or non-physical characteristic of said article;
an image processing module, said image processing module configured to:
process said image to generate one or more second information corresponding to said image;
compare said first information to said second information and generate an output indicating said physical and/or non-physical characteristic of said article; and thereby
generate at least one actionable signal,
wherein, said actionable signal subsequently transmitted to said interfacing means, said interfacing means configured to generate at least one synchronized actionable signal and thereby said transmit said synchronized actionable signal to said maker device to perform at least one action.

2. The system as claimed in claim 1, wherein said article is particularly a rod-like article selected from plurality of said rod-like articles.

3. The system as claimed in claim 2, wherein said rod-like article is preferably a cigarette article.

4. The system as claimed in claim 1, comprises an illumination device in addition to said image capturing means, to enable greater imaging of said image of said article.

5. The system as claimed in claim 4, wherein said illumination device comprises a light source received by using at least one Light Emitting Diode (LED).

6. The system as claimed in claim 1, wherein said maker device is formed by the combination of a manufacturing apparatus, Inspection drum and a rejection System

7. The system as claimed in claim 1, wherein said speed signal is generated based on a movement of said article on said maker device, and said speed signal is thereby used to enable said image capturing means to capture said image of said article.

8. The system as claimed in claim 1, wherein said imaging capturing means comprises of at least one selected from a high speed solid state device or charged coupled device.

9. The system as claimed in claim 1, comprises an interfacing means is preferably a microcontroller.

10. The system as claimed in claim 1, wherein said first information pre-stored in said data storing comprises at least one information selected from an alphanumeric identifier, a description, a name, or a title or graphical pattern or logo or any combination thereof.

11. The system as claimed in claim 1, wherein second information is at least one information selected from a textual marker or differentiators or logo or patterns or colors or graphics or any combination thereof, imprinted on a body of said article.

12. The system as claimed in claim 11, wherein said second information is generated by at least one Optical Character Recognition section in said image processing module.
13. The system as claimed in claim 1, wherein said synchronized actionable signal corresponds to a delay signal between said speed signal and said actionable signal.

14. The system as claimed in claim 1, wherein said action corresponds rejecting said article, directing said article to at least one downstream system or any combination thereof.

15. The system as claimed in claim 1, wherein said physical characteristics of said article includes at least one selected from a circumference, length, width, weight, variant name, stylized text, special text, logo, graphics, tipping design, ventilation, filter type, color of print or tipping or any combination thereof.

16. The system as claimed in claim 1, wherein said non-physical characteristics of said article includes but is not limited to at least one selected from Tobacco Type, smoke profile, quality, physical tobacco type, flavor or any combination thereof.

17. A method for identifying at least one physical and/or non-physical characteristic of at least one article from plurality of said articles, said method comprising:
pre-storing, using at least one data storing means, at least one first information corresponding to said article;
receiving, by at least one maker device, plurality of said articles for processing;
generating, by at least one interfacing means, at least speed signal based on a movement of said article, wherein said interfacing means is communicably coupled to said maker device and at least one image processing device;
actuating, by said speed signal, at least one image capturing means and thereby receiving at least one image of said article;
transmitting, said image to said image processing device by at least communication module;
processing, by at least one image processing module in said image processing device, said image and thereby generating, at least one second information corresponding to said physical and/or non-physical characteristic of said article;
comparing, by said image processing device, said first information and said second information and thereby generating an output based on said comparison;
generating, by said image processing device, at least one actionable signal based on said output, and thereby transmitting said actionable signal to said interfacing means;
generating, by said interfacing means, at least one synchronized actionable signal based on said actionable signal and said speed signal, and thereby transmitting said synchronized actionable signal to said maker device for performing at least one action.

18. The method as claimed in claim 17, wherein said synchronized actionable signal corresponds to a delay signal between said speed signal and said actionable signal.

19. The method as claimed in claim 17, wherein said action includes rejecting and/or accepting said article based on said physical and/or non-physical properties.

20. The method as claimed in claim 17, wherein said speed signal corresponds to speed of movement of said rod shaped article on at least one rotatable inspection drum of a maker machine.

21. The method as claimed in claim 17, wherein said first information corresponding to said article, comprises at least one information selected from an alphanumeric identifier, a description, a name, a title, a graphical pattern or a logo or any combination thereof.

22. The method as claimed in claim 17, wherein second information is at least one information selected from a textual marker or differentiators or logo or patterns or colors or graphics or any combination thereof, imprinted on a body of said article.

23. The method as claimed in claim 22, wherein said second information is generated by at least one Optical Character Recognition section in said image processing module.

24. The method as claimed in claim 17, wherein said physical characteristics of said article includes at least one selected from a circumference, length, width, weight, variant name, stylized text, special text, logo, graphics, tipping design, ventilation, filter type, color of print or tipping or any combination thereof.

25. The method as claimed in claim 17, wherein said non-physical characteristics of said article includes but is not limited to at least one selected from variant, smoke profile, quality, physical tobacco type, flavor or any combination thereof.
, Description:TECHNIAL FIELD

[001] The present subject matter described herein, in general, relates to the identification of various identity markers of an article such as cigarettes, from plurality of said articles, and more particularly to the use of a field of vision and image processing computer technology in determining non-physical and/or physical characteristics of the said article.
BACKGROUND

[002] Conventionally, smoking articles such as cigarettes are manufactured with a traditional white and brown look which has its own aesthetics, wherein to achieve the same, cigarette paper and tipping paper respectively are utilized. This has also served the purpose of identifying a cigarette variant. In present days, cigarette articles uses plethora of differentiating factors for improved aesthetics and variant identification. Such differentiators may include, text, logos, designs, images, color codes, or printed matter on the surface of the product. In addition, the general trend of increasing product variants also makes scheduling production runs and changeovers more complex and prone to mistakes. This results in inaccuracies in manual scheduling of production runs, leading to a significant production loss.

[003] There are existing reports of incorrect changeovers and therefore, manufacture of product with incorrect specifications. For example, a particular variant of cigarettes having specifications, that includes but not limited to, printed matter or logo of another variant. This results in situations of batch recall of goods as they violate the consumer requirement of product consistency.

[004] Until now, attempts have been made to capture defects on the cigarette using imaging technology.

[005] JP2009171967A, discloses an optical scanning unit for scanning tobacco products of elongated shape optically. The optical scanning unit is for testing the visual integrity of cigarettes. Further, the prior art WO03026448A1, discloses a Visual inspection system for rod-like article. Furthermore, the prior art JP2002148205A discloses a surface-inspecting apparatus for bar-shaped bodies which can efficiently inspect surfaces of a plurality of bar-shaped bodies while continuously transferring the bodies at high speeds. However, they are focused on capturing cigarette quality or stick quality rather than the physical and/or non-physical properties.

[006] The determination of non-physical properties is used for activities such as automated scheduling or changeover. Such activities would include directing cigarettes to appropriate packing machines through automated conveyors. It is also possible to use this information for incorrect specification and rejection.

[007] Prior art reference US20060098214A1, wherein a method of determining one or more physical properties of a rolled smoking article is disclosed, the method comprising disposing a rolled smoking article within a field of view, illuminating the field of view, imaging the rolled smoking article to form an image, and analyzing the image to determine one or more physical properties of the rolled smoking article. However, the method recites about a determination of physical properties only, which includes but not limited to, a diameter, length and ovality. Furthermore, it does so by rotating each cigarette on two rollers making the process time consuming and therefore, offline.

[008] However, the above mentioned prior art discloses the method to determine physical properties only. In addition to this, the system disclosed is an offline system, i.e., it is intended to be a lab quality testing instrument and can check one cigarette at a time at limited speed. This is illustrated by use of a screw based mechanism, in absence of a cigarette making machine speed signal generator and absence of a rejection signal mechanism.

[009] Thus, in view of the hitherto prior art, there exists a dire need to provide an improved mechanism for detection of physical and/or non-physical characteristics of an article, and thereby overcome the drawbacks of the existing mechanisms. Preferably, the present invention renders a system and method that checks the cigarette body/surface for specific markers to identify the particular variant and takes action accordingly. More preferably, if variant 1 is supposed to be run on Machine 1 and materials of variant 2 is loaded on the machine, it will automatically detect the issue, reject the mismatched cigarette articles.

SUMMARY OF THE INVENTION

[0010] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[0011] An object of the present invention is to provide an improved system for identifying physical and/or non-physical characteristics of an article from a plurality of articles by using an image processing technology.

[0012] It is an object of the present invention is to provide a method of determining physical properties and/or non-physical characteristics of a rod-shaped article, so as to enable automatic scheduling and/or changeover, directing the articles to appropriate packing machines through conveyor and the like.

[0013] Yet another object of the present invention is to allow the variation in the physical and/or non-physical characteristics of a rod-shaped article, such as cigarettes and the like, to be monitored substantially in real time.

[0014] Still another object of the present invention is to provide a system for identification of a physical and/non-physical properties of a rod-shaped article, which is easy to implement and cost effective.

[0015] Accordingly, in one aspect of the present invention, there is provided a system for identifying at least one physical and/or non-physical characteristics of at least article from plurality of said articles, said system comprising:
at least one maker device to receive said articles for processing;
at least one interfacing means operably coupled to said maker device, to sense at least one speed of said article and generate at least one speed signal;
at least one image capturing means, to receive at least one image of said article and thereby communicate said image to an image processing device, wherein said image processing device comprises:
at least one data storing means, to pre-store at least one first information corresponding to said physical and/or non-physical characteristic of said article;
an image processing module, said image processing module configured to:
process said image to generate one or more second information corresponding to said image;
compare said first information to said second information and generate an output indicating said physical and/or non-physical characteristic of said article; and thereby
generate at least one actionable signal,
wherein, said actionable signal subsequently transmitted to said interfacing means, said interfacing means configured to generate at least one synchronized actionable signal and thereby said transmit said synchronized actionable signal to said maker device to perform at least one action.

[0016] In yet another aspect of the present invention, there is provided a method for identifying at least one physical and/or non-physical characteristic of at least one article from plurality of said articles, said method comprising:
· pre-storing, using at least one data storing means, at least one first information corresponding to said article;
· receiving, by at least one maker device, plurality of said articles for processing;
· generating, by at least one interfacing means, at least speed signal based on a movement of said article, wherein said interfacing means is communicably coupled to said maker device and at least one image processing device;
· actuating, by said speed signal, at least one image capturing means and thereby receiving at least one image of said article;
· transmitting, said image to said image processing device by at least communication module;
· processing, by at least one image processing module in said image processing device, said image and thereby generating, at least one second information corresponding to said physical and/or non-physical characteristic of said article;
· comparing, by said image processing device, said first information and said second information and thereby generating an output based on said comparison;
· generating, by said image processing device, at least one actionable signal based on said output, and thereby transmitting said actionable signal to said interfacing means;
· generating, by said interfacing means, at least one synchronized actionable signal based on said actionable signal and said speed signal, and thereby transmitting said synchronized actionable signal to said maker device for performing at least one action.

[0017] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:

[0018] Figure 1 illustrates a schematic of the entire system including stages such as manufacture, inspection, imaging, processing, rejection and further action. It also depicts the flow of product and information.

[0019] Figure 2 illustrates a rod shaped article such as a cigarette indicating possible areas containing differentiating markers (physical characteristic),in accordance with an embodiment of the present invention.

[0020] Figure 3 illustrates a schematic showing flow of information through the system, in accordance with an embodiment of the present invention.

[0021] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0022] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0023] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0024] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0025] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0026] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0027] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0028] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0029] In one implementation, an article such as a rod-shaped article as shown in figure 2 may include, but not limited a smoking article like cigarette, filter rod and the like. In the present embodiment the words “cigarette”, “filter rod” have been used interchangeably. It is to be noted that though the present invention specifically concerns identification of physical and/or non-physical properties of cigarettes, the same system and method can be used for any article other than cigarette. It is not necessary that such articles need to be rod like and can be of any other shape and still the system and method of the present invention can identify the physical and/or non-physical properties of the said articles.

[0030] In one implementation, the rod-shaped article, preferably a cigarette article includes the physical that is illustrated in figure 2 elucidates the cigarette article as follows:
· 40– Depiction of cigarette stick
· 41 – Identifying marker on cigarette paper
· 42 – Identifying marker on tipping area
· 43 – Identifying marker on tipping paper

[0031] In all implementation, the present invention discloses a system and method that checks the cigarette body/surface for specific markers to identify the particular variant and takes action accordingly. In one implementation, the system is designed in such a way that if article variant 1 is supposed to be run on Machine 1 and materials of article variant 2 is loaded on the machine, it will automatically detect the issue, reject the mismatched cigarette articles. Furthermore, it is designed to be operated online on a modern day cigarette making machine which typically operate at speeds up to 20,000 cigarettes per minute.

[0032] In all the implementation, cigarettes have various differentiating markers on the body such as logos, text, marks, designs and so on. Each of these markers is unique to a specific variant of cigarettes. These are known as physical characteristics. Therefore, by detecting these physical differentiating markers, it is easy to know the variant of the cigarettes. Once the variant is known, non-physical properties such as tobacco smoke type, blend and the like, can be easily known from the pre-stored information in database. This information can be subsequently actioned upon.

[0033] The term “physical characteristic” of the cigarette articles shall include, Cigarette and Filter Dimensions, Circumference, Weight, Raw Materials to be used, Color of print and tipping, Ventilation, variant name, stylized text, special text, logo, graphics, tipping design, filter type or any combination thereof.

[0034] The term “non-physical characteristic” of the cigarette articles shall include, Blend Design, Tobacco Type, Blend Brief, Manufacturer, Blend Specifications and Formula, smoke profile, quality, physical tobacco type, flavor or any combination thereof.

[0035] Reference made to Figure 1,wherein a schematic of filter plug attachment section of making machine, with an image capturing device suitably positioned, in accordance with an embodiment of the present invention, is illustrated. The various components as illustrated in the figures defines as follows:

1. 10– Manufacturing
2. 11– Inspection drum
3. 12– Rejection System
4. 13 – Downstream machinery
5. 20 – Image processing device
6. 21 – Interfacing means
7. 22 – Image capturing means
8. 23 –Image Processing module
9. 24 – Database
10. 31, 33 – Control signal to take this forward to downstream machinery
11. 32 – Rejection signal

[0036] In one implementation, the automated system as shown in figure 1, for identifying non-physical and physical properties of a cylindrical rod shaped articles operated on a maker machine / inspection drum (11), whereby leads to zero defect, comprising;
§ an image capturing means(22) to capture images of the cigarette;
§ an image processing device (20) having one or more image processing module (23), to process the images for determination of physical and/or non-physical characteristics of the cigarette;
§ an interfacing means (21) to aid in communication between said image capturing means (22); said image processing device (20);
§ an illumination device to aid in better imaging (not shown, it is a part of image processing module itself) and

[0037] In one implementation, manufacturing apparatus (10), rejection system (11) and inspection drum (12) together constitutes the maker machine.

[0038] In one implementation, the interfacing means (21) is configured to facilitate a communication between said maker machine and said image processing device (20). The interfacing means (21) is a microcontroller and the like. The interfacing means calculates a speed of said maker machine (11) and rotational distance between said rotatable inspection drum/maker machine (11) and said rod shaped article, thereby generating a speed signal. The speed signal is transmitted to an image capturing means (22) to receive an image of the rod-shaped article. The speed signal corresponds to at least one single cigarette pulse (SCP).

[0039] In one implementation, the image processing device (20) comprises the image processing module to process the images received by the image capturing device. The image processing module (23) further includes Optical character recognition algorithm to identify names of the brands, colors in logos or graphics and such other optical characters of the cigarette. The image processing device can be any specialized computing device that includes but not limited personal computers, laptops, mobile phones, smart-phones and such other electronic devices. The image processing device is a specialized hardware device that comprises a memory to store image processing modules/instructions and a database, and a processing unit to execute the image processing modules so to that the image processing device can perform the desired actions. The image processing device of the present invention is dedicated for identifying the physical and/or non-physical properties of the rod-shaped article such as cigarette.

[0040] In one implementation, a cigarette to be identified may be positioned on an inspection drum or a making machine (11). The cigarettes are transferred to the inspection drum (11) after the completion of a cigarette, at a speed ranging from 0to 20000 cigarettes per minute. It further generates an input signal comprising a speed signal that is generated based on a movement of said article. A high speed solid state image capturing means (22) coupled with appropriate illuminating agent is placed near this inspection drum (11) to enable imaging capabilities.

[0041] In one implementation, images of the rod-shaped articles as shown in figure 2, may be captured, preferably in groups of four cigarettes at a time by using the image capturing means (22). The image captured is a digital image. The image capturing means (22) comprises at least one selected from a high speed solid state device or charged coupled device and the like. It may include a digital camera or a digital video-camera. The image capturing means (22) is attached adjacent to, preferably on top of, any of the rotatable inspection drums in said cigarette making machine (11), preferably subsequent to filter attachment and most preferably the inspection drum (11).

[0042] In one implementation, the image is captured in real time using the image capturing means (22)and thereby may be sent to Image Processing device (20) as shown in figure 1.

[0043] In one implementation, the image processing device (20) pre-stores first information corresponding to said article, comprises at least one information selected from an alphanumeric identifier, a description, a name, a specification, or a title or graphical pattern or logo or any combination thereof. The first information is pre-stored in the image processing device (20) using a one or more data storing means (24). An instruction database is coded accordingly and saved beforehand. If it is primarily for identifying specification mismatch, a reject signal is sent to the maker rejection system. If it is used to make downstream decisions, a command signal is sent to relevant downstream machinery.

[0044] In one implementation, cigarettes have markers on the tobacco rod or the tipping paper. These may be in the form of variant names, logos, text, stylized text, special text or graphics. These markers are processed electronically by the Image Processing devices (20) and thereby isolated using the image processing module (23) in the form of second information. The Optical Character Recognition module are used to read names of variants. Colors in logos or graphics are also detected. A comparison of them against the database (24) helps to identify the physical and/or non-physical properties (as shown in figure 2). Once the variant is known, non-physical properties (tobacco smoke type, blend characteristics etc.) can be easily known from the database. This information can be subsequently actioned upon.

[0045] In all implementation, the image may be processed electronically to determine the physical and/or non-physical properties of the article. The physical characteristics of said article may include at least one selected from a circumference, length, width, weight, variant name, stylized text, special text, logo, graphics, tipping design, ventilation, filter type, color of print or tipping or any combination thereof. The non-physical characteristics of said article may include at least one selected from variant, smoke profile, quality, physical tobacco type, flavor, blend condition or any combination thereof.

[0046] In one implementation, the image processing module (20) is configure to perform a comparison between the pre-stored first information and the second information and thereby generate an output. The output corresponds to an actionable signal. The actionable signal is thereby transmitted to an interfacing means for subsequent processing.

[0047] In one implementation, the interfacing means generates a synchronized actionable signal by counting the delay between the signal cigarette pulse and the actionable signal to generate a synchronized actionable signal. The synchronized actionable signal is thereby transmitted to the maker device to perform suitable action. The action corresponds rejecting the cigarette article by means of a rejecting system or directing the article to at least one downstream system for selection.

[0048] In one implementation, the system and method further comprises an illumination device in addition to said image capturing means (22), to provide greater imaging of said image of said article. The illumination device may comprise a light source received by using at least one Light Emitting Diode (LED) and the like.

[0049] In one implementation, as illustrated in figure 3, an automated method of identification of non-physical and physical properties of a cylindrical rod shaped articles, which is operated on a maker machine (11), whereby leads to zero defect, said method comprises of the following steps of:
· sensing speed of movement of said rod shaped article on a rotatable inspection drum of a maker machine (11) and generating a speed signal using said interfacing means (21);
· generating and sending a single cigarette pulse (31) for said rod shaped article through interfacing means for instructing at least one image capturing means (22) to capture images of said rod shaped article;
· capturing images of said rod shaped articles being conveyed on said rotatable inspection drum (11), of said maker machine using said image capturing means (22);
· processing and determining the non-physical and physical properties of the said rod shaped article in said image captured by said image capturing means (22) using said processing means (23);
· generating an actionable signal based on desired output, including but not limited to rejecting said rod shaped article or directing it to respective downstream machine (13) based on the properties;
· measuring a delay between said single cigarette pulse and said actionable signal to generate a synchronized actionable signal (33);
· transmitting said synchronized actionable signal to relevant hardware (13) to carry out desired actions on said rod shaped article.

[0050] In one implementation, said desired action includes discriminating said rod-shaped article based on said physical and/or non-physical properties. The rod-shaped article is rejected in case of specification mismatch or the like using technologies such as the rejection unit built (12, 32) into the maker machine (11).

[0051] In one implementation, the present invention can help in automating facilities that have different types or multiple downstream machinery (13) connected to them. For example, if one or more making machines are connected to multiple buffers or packing machines with a switching conveyor system between them, the identity of the physical and/or non-physical properties can be used to automatically drive the switch to redirect the flow of the conveyor belt to the correct buffer or packer. Additionally, most modern day cigarette makers have an in built facility of rejecting cigarettes based on combined inputs from certain sensors. This facility can be leveraged to reject out cigarettes in case of a specification mismatch.

[0052] In one implementation, the speed signal generated here is basically the indicating the machine speed. It is essential to synchronize the rejection system with the maker device so that only the faulty cigarette is rejected at a later stage.

[0053] Some of the advantages of the present invention, considered to be noteworthy are mentioned below:
1. The present invention provides identification of physical and/or non-physical characteristics of said rod-shaped article.
2. The present invention may be used for specification identification and rejection.
3. The present invention is an automated system or method that can perform said identification in real time based on differentiating markers and initiate required action.

[0054] Although a system, and a method thereof for identifying physical and/or non-physical properties of an article, that have been described in language specific to structural features and/or methods, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or methods or devices described. Rather, the specific features are disclosed as examples of implementations of the system, and a method thereof for identifying physical and/or non-physical properties of an article.