5.4.2.4 Example 4 

Claim 1:

A computer-implemented method of determining areas in which there is an increased risk of condensation for a surface in a building comprising the steps of:

(a)controlling an infrared (IR) camera to capture an image of the temperature distribution of the surface;

(b)receiving mean values for the air temperature and the relative air humidity measured inside the building over the last 24 hours;

(c)calculating, based on said mean air temperature and mean relative air humidity, a condensation temperature at which there is a risk of condensation on the surface;

(d)comparing the temperature at each point on the image to said calculated condensation temperature;

(e)identifying the image points having a temperature lower than the calculated condensation temperature as areas at increased risk of condensation on the surface; and

(f)modifying the image by colouring the image points identified in step (e) in a particular colour to indicate the areas at increased risk of condensation to a user.

Application of the steps of the problem-solution approach according to G‑VII, 5.4:

Step (i): The control of an IR camera in step (a) clearly makes a technical contribution. The question is whether steps (b) to (f) also contribute to the technical character of the claimed subject-matter.

Considered in isolation, steps (b) to (e) relate to algorithmic/mathematical steps and step (f) defines a presentation of information. However, the claim is not directed to a mental act, a mathematical method or presentation of information as such (which would be excluded from patentability under Art. 52(2)(a), (c), (d) and Art. 52(3)) because the claimed subject-matter involves technical means such as a computer.

Therefore, it has to be assessed whether the algorithmic and mathematical steps as well as the step related to presentation of information do, in the context of the invention, contribute to producing a technical effect, thereby contributing to the technical character of the invention.

Since the above-mentioned algorithmic and mathematical steps (b) to (e) are used to predict the physical state (condensation) of an existing real object (surface) from measurements of physical properties (IR image, measured air temperature and relative air humidity over time), they contribute to a technical effect serving a technical purpose. This applies regardless of what use is made of the output information about the risk of condensation on the surface (see G-II, 3.3, in particular subsection "Technical applications"). Thus, steps (b) to (e) contribute also to the technical character of the invention.

A decision on whether step (f) makes a technical contribution is deferred to step (iii) below.

Step (ii): Document D1 discloses a method for monitoring a surface to determine the risk of condensation forming on it. The risk of condensation is determined based on the difference of the temperature reading obtained via an IR pyrometer for a single point on the surface and the condensation temperature calculated based on the actual ambient air temperature and the relative air humidity. The numerical value of the difference is then shown to a user as an indication of the likelihood of condensation at said point. This document is taken as the closest prior art.

Step (iii): The differences between the subject-matter of claim 1 and D1 are:

(1)an IR camera is used (instead of the IR pyrometer of D1, which only captures the temperature at a single point of the surface);

(2)mean values for air temperature and relative air humidity measured inside the building over the last 24 hours are received;

(3)the condensation temperature is calculated on the basis of the mean air temperature and mean relative air humidity and compared to the temperature at each point on the IR image of the surface;

(4)image points having a temperature lower than the calculated condensation temperature are identified as areas at increased risk of condensation on the surface;

(5)colours are used to indicate areas at increased risk of condensation.

As mentioned above, distinguishing features (1)-(4) contribute to the technical character of the claimed subject-matter and must be taken into consideration for the formulation of the technical problem. These features produce the technical effect of a more precise and reliable prediction of the risk of condensation as a result of considering all surface areas (as opposed to a single point) and accounting for temperature variations during a day.

Distinguishing feature (5) defines a particular manner of presenting information to a user (Art. 52(2)(d)) which does not produce a technical effect since any effect of the choice of displaying data using colours rather than numerical values depends on subjective preferences of the user: some users may prefer the former and other the latter (see G‑II, 3.7). This feature thus does not make a technical contribution. It cannot support the presence of an inventive step and is not discussed further in the analysis since it has no bearing on the other distinguishing features.

Step (iii)(c): The objective technical problem is therefore formulated as how to determine the risk of condensation on a surface in a more precise and reliable manner.

Obviousness: The use of an IR camera for obtaining temperature readings on a surface can be considered a normal technical development in the field of thermography without exercising any inventive activity: IR cameras were well known at the effective date of the application. Using an IR camera is a straightforward alternative to measuring the temperature at several points on the monitored surface using an IR pyrometer for the skilled person to arrive at a temperature distribution of the surface.

However, D1 does not suggest considering a temperature distribution on a surface (as opposed to at a single point) and calculating mean values for air temperature and taking relative air humidity measured inside the building over the last 24 hours into consideration. Neither does it suggest taking into account different conditions which may realistically occur inside the building over time for predicting the risk of condensation.

Assuming that no other prior art suggests the technical solution of the objective technical problem defined by distinguishing features (1)-(4), the subject-matter of claim 1 involves an inventive step.

Remarks: This example illustrates the situation addressed in G‑VII, 5.4, second paragraph: features which, when taken in isolation, are non-technical but do, in the context of the claimed invention, contribute to producing a technical effect serving a technical purpose (features (b) to (e), which are algorithmic/mathematical steps). Since said features contribute to the technical character of the invention, they may support the presence of an inventive step.

Claim 1:

A computer-implemented method for the numerical simulation of the performance of an electronic circuit subject to 1/f noise, wherein:

(a)the circuit is described by a model featuring input channels, noise input channels and output channels;

(b)the performance of the input channels and the output channels is described by a system of stochastic differential equations;

(c)an output vector is calculated for an input vector present on the input channels and for a noise vector y of 1/f-distributed random numbers present on the noise input channels; and

(d)the noise vector y is generated by the following steps:

(d1)setting the number n of random numbers to be generated;

(d2)generating a vector x of length n of Gaussian-distributed random numbers;

(d3)generating the vector y by multiplying the vector x with a matrix L defined according to equation E1*.

* It is assumed that equation E1 is explicitly specified in the claim.

Background: The claim is directed to a method carried out by a computer for the numerical simulation of the performance of an electronic circuit subject to 1/f noise, which is one of the main sources of noise in electronic circuits. Features (a)-(c) specify the mathematical model used in the numerical simulation. It involves a noise vector y of 1/f-distributed random numbers, i.e. random numbers having a particular statistical property typical of real (physical) 1/f noise. Steps (d1)-(d3) define the mathematical algorithm used for generating these random numbers. According to the description, this mathematical algorithm is particularly efficient in terms of computation time and storage resources required to generate the random numbers needed for the simulation.

Application of the steps of the problem-solution approach according to G‑VII, 5.4:

Step (i): The use of a computer to carry out the claimed method is a clearly technical feature. The question is whether the other features, in particular the mathematical algorithm of steps (d1)-(d3), also contribute to the technical character of the claimed subject-matter. Considered in isolation, steps (d1)-(d3) represent a mathematical method with no technical character. However, the claim is not directed to this mathematical method as such (which would be excluded from patentability under Art. 52(2)(a) and (3)) but is limited to a computer-implemented method in which this mathematical method serves the numerical simulation of the performance of an electronic circuit subject to 1/f noise, which is considered to be a technical purpose (G‑II, 3.3). Features (a)-(c) ensure that the claim is functionally limited to this technical purpose by specifying the mathematical model used in the simulation and how the generated noise vector y is used in it, i.e. they establish the link between the stated purpose of the method and steps (d1)-(d3). Furthermore, the mathematical model specified by features (a)-(c) defines how the numerical simulation is performed and thus also contributes to the above-mentioned technical purpose. As a result, all the steps relevant to the circuit simulation, including the mathematically expressed claim features (d1)-(d3), contribute to the technical character of the method to the extent that they are relevant for circuit simulation.

Step (ii): Document D1, which discloses a method for numerical simulation of the performance of an electronic circuit subject to 1/f noise with steps (a)-(c) but with a different mathematical algorithm for generating the 1/f-distributed random numbers, is selected as closest prior art.

Step (iii): The difference between the methods of claim 1 and D1 is the mathematical algorithm used to generate the vector of 1/f-distributed random numbers, i.e. steps (d1)-(d3). The algorithm defined by steps (d1)-(d3) requires less computer resources than that used in D1. In the context of the claimed method, this results directly in a reduction of the computer resources required for the numerical simulation of the performance of an electronic circuit subject to 1/f noise, which is the technical effect achieved over D1.

Step (iii)(c): The objective technical problem solved with respect to D1 is formulated as how to generate the 1/f-distributed random numbers used in the numerical simulation of the performance of an electronic circuit subject to 1/f noise in a manner which requires less computer resources.

Obviousness: No prior art suggests the algorithm defined by steps (d1)-(d3) as a solution to the objective technical problem. The invention as claimed is therefore considered to involve an inventive step.

Remarks: This example illustrates the situation addressed in G‑VII, 5.4, second paragraph: features which, when taken in isolation, are non-technical, but do, in the context of the claimed invention, contribute to producing a technical effect serving a technical purpose. Such features are considered to contribute to the technical character of the invention and may therefore support the presence of an inventive step.

Note that if the claim were not limited to the numerical simulation of an electronic circuit subject to 1/f noise, the mathematical algorithm defined by steps (d1)-(d3) would not serve any technical purpose and would thus not be considered to contribute to the technical character of the claim (requiring less computer resources than another mathematical algorithm being on its own not sufficient in this respect; see G‑II, 3.3).