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Heidarnejad, et al.


                  The influence of the gravitational acceleration   gB 5  ,   C=F   w 1  ,  H d  ,  w          (XI)
                                                                                      
                                                                                     1
                                                                          
                                                            Q 2       d     B  B w  2 
                which  represents  the  Froude  number,  is  incorporated
                through the dimensionless parameter   H d  . Given these   2.3. MLMs
                                                  B
                conditions,  Equation  X  is  simplified  to  the  following   2.3.1. SVM
                                                                                                    41
                Equation XI:                                        Developed  by  Cortes  and  Vapnik,  the  SVMs are  a
                                                                    class of supervised learning  methods  used for
                                                                    classification and regression tasks in machine learning.
                A                                                   They are particularly well-suited for binary classification
                                                                    problems, though extensions to multiclass classifications
                                                                    exist. The core concept behind SVM is the construction
                                                                    of hyperplanes in a high-dimensional space that can be
                                                                    used to separate different classes of data points.  Given
                                                                                                              38
                                                                    a training  dataset  {(X,y)} , where  X ∈
                                                                                                 N
                                                                                                                    n
                                                                                               i
                                                                                            i
                                                                                                               i
                                                                                                 i=1
                                                                    represents the feature vectors and y ∈{-1,1} represents
                                                                                                    i
                                                                    the  class  labels,  the  objective  of  SVM  is  to  find  a
                B
                                                                    hyperplane that maximally separates the two classes. 42
                                                                       To model a problem using SVM, the first step is to
                                                                    clearly define the problem by determining whether it is a
                                                                    classification, regression, or outlier detection task. Once
                                                                    the task is identified, the next step involves collecting
                                                                    and preprocessing the dataset to ensure that the data are
                                                                    clean, normalized, and suitable for modeling. Based on
                                                                    the nature and structure of the data, an appropriate kernel
                                                                    function is then selected to transform the input space if
                                                                    necessary. After selecting the kernel, the dataset is split
                                                                    into training and testing sets, typically using an 80:20
                                                                    ratio, to evaluate the model’s performance on unseen
                                                                    data. The next step is to set the key hyperparameters
                                                                    of  the  SVM model.  These  include  the  regularization
                                                                    parameter  C,  which  controls  the  trade-off  between
                Figure  1.  Flume  and  weirs  model  of  experiments:   achieving a wide margin and minimizing classification
                (A) Plan view of the setting. (B) Geometry parameters   errors, and other kernel-specific parameters, such as γ
                of the trapezoidal-arched labyrinth weirs (TALWs)   for the radial basis function (RBF) kernel or the degree
                Notes: B is the weir height on the upstream side; R is   for polynomial kernels.  With the data  prepared and
                the arc radius; t is the crest thickness; W is the width of   parameters set, the model is trained using the training
                a cycle; W  is the inside apex width of the middle cycle;   dataset. During training, the SVM algorithm attempts to
                         1
                W  is the inside apex width of the end cycle.       maximize the margin between classes in classification
                  2











                Figure 2. Shape and geometric parameters of the labyrinth weir
                Notes: α is the wall angle; A is inside apex width, X-X is cross section of the weir; B is the weir length; D is the apex
                width; H is the depth head; H  is the total upstream head; h  is the velocity head; L  is the wall length; P is the weir height;
                                        t
                                                                 t
                                                                                    c
                Q is the flow discharge; T is the weir height; t is the crest thickness; W is the total width; w is the width of a cycle.

                Volume 22 Issue 6 (2025)                        78                           doi: 10.36922/AJWEP025120081
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