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Abstract

Wargames are important methods for military planning, education and research. Qualitative models have a long tradition in wargaming for improving and practising the military skills as well as enhancing the military planning based on the experiences and understanding of the experts. Quantitative models are included in simulations and technical studies. Traditionally, the relations between the qualitative and quantitative research have been described as opposites. We shall consider both the approaches, their challenges and possibilities, and their combination for producing more exhaustive wargame and for answering to the criticism of wargame as a mainly qualitative method.

Our main research question is: How to combine quantitative and qualitative approaches and methods to improve quality of results of military wargames? Our main objective is to clarify and illustrate how qualitative and quantitative methods can be combined through the wargame. We shall emphasize the importance of the model selection at the beginning as it limits and guides the form (not the content) of the obtained results. We shall illustrate a combined wargame within different steps and the modelling themes of the game. Our results and findings should be useful for improving and focusing wargames to answer given research questions.

Summary

The usefulness of combining methods is examined using the example of microarray cancer data sets, where expression levels of huge numbers of genes are reported. Problems of discrimination into two groups are examined on three data sets relating to the expression of huge numbers of genes. For the three examined microarray data sets, the cross-validation errors evaluated on the remaining half of the whole data set, not used earlier for the selection of genes, were used as measures of classifier performance. Common single procedures for the selection of genes—Prediction Analysis of Microarrays (PAM) and Significance Analysis of Microarrays (SAM)—were compared with the fusion of eight selection procedures, or of a smaller subset of five of them, excluding SAM or PAM. Merging five or eight selection methods gave similar results. Based on the misclassification rates for the three examined microarray data sets, for any examined ensemble of classifiers, the combining of gene selection methods was not superior to single PAM or SAM selection for two of the examined data sets. Additionally, the procedure of heterogeneous combining of five base classifiers—k-nearest neighbors, SVM linear and SVM radial with parameter c=1, shrunken centroids regularized classifier (SCRDA) and nearest mean classifier—proved to significantly outperform resampling classifiers such as bagging decision trees. Heterogeneously combined classifiers also outperformed double bagging for some ranges of gene numbers and data sets, but merging is generally not superior to random forests. The preliminary step of combining gene rankings was generally not essential for the performance for either heterogeneously or homogeneously combined classifiers.

Abstract

A combined method for on-line signature verification is presented in this paper. Moreover, all the necessary steps in developing a signature recognition system are described: signature data pre-processing, feature extraction and selection, verification and system evaluation. NNs are used for verification. The influence of the signature forgery type (random and skilled) over the verification results is investigated as well. The experiments are carried out on SUsig database which consists of genuine and forgery signatures of 89 users. The average accuracy is 98.46%.

Abstract

Introduction: Sentinel node biopsy is the gold standard for axillary assessment of patients with breast cancer without axillary metastases on clinical and radiological examination. Internationally accepted biopsy methods currently use a radioactive tracer (Te) or different variations of vital stain, or the combination of the two. Due to the high cost of technical and organizational difficulty related to the radioactive material, as well as the disadvantages of using the vital stain method, great effort is being made to find alternative solutions. The aim of this study was to determine the effectiveness of the exclusive use of vital stain versus the radioactive isotope, and the need to use the combined method. A second goal was the comparative analysis of the radioactive method and intraoperative assessment of suspicious (non-sentinel) lymph nodes.

Materials and methods: This article is based on a prospective nonrandomized study conducted on 69 patients with early breast cancer in whom the combined method was used (injection of radionuclide and methylene blue vital stain). The comparatively monitored parameters were the following: the total and mean number of excised sentinel lymph nodes, the number of metastatic ganglia revealed by the 2 methods, and the risk of understaging in case only one technique was used.

Results: We excised 153 sentinel nodes identified by the radioisotope method. Of these only 56 were stained with methylene blue (p <0.0001). We could also identify a significantly higher number of metastatic nodes with the aid of the radioactive method (p = 0.0049). Most importantly, a significant number of patients (57.14%) who would have been declared node-negative using vital staining could only be properly staged using the radionuclide or the combined method. On microscopic examination of 35 non-sentinel lymph nodes, we found 3 lymph nodes with metastases, and in 1 case the metastases were found only in the non-sentinel lymph node.

Conclusions: Given the risk of understaging, exclusive use of the vital stain method is not recommended, especially under the ASGO Z 00011 Protocol, since the more accurate determination of the number of metastatic sentinel lymph nodes in a patient influences the decision whether to perform lymphadenectomy or not. Using the combined method confers benefits only during the learning curve, in our database we found no stained nodes which were not radioactive. It is very important that the intraoperative stage uses the radioactive method and the intraoperative assessment of suspicious lymph nodes, because 35 non-sentinel lymph nodes were identified in our study, 3 of which had metastases, while in 1 case the metastases were in the non-sentinel lymph node.

Abstract

In this research, a combined method was developed to determine the erodibility of bends in the Karkheh River. For this purpose, a 40 km reach of the Karkheh River downstream of the Karkheh Dam was considered. The value of the shear stress was the calculated using the CCHE2D model. The results from the model show that in 1996 (before construction of the Karkheh dam), the length of the erodible reach was 1314 m; in 2011 (after construction of the Karkheh dam), this length was reduced to 840 m. Furthermore, the model illustrates that the location of the maximum shear stress is a function of the relative curvature (R/W) in the bends. For small values of the R/W (less than 1.5), the maximum shear stress occurs on the convex bank of a river bend. By increasing the R/W, the location of the maximum shear stress transfers to the concave bank of the river bend. Also, this location is displaced towards downstream by increasing the R/W.

Abstract

Background: Starting from the limitations of different single-method approaches to measuring the organizational efficiency, the paper is focused on covering both the financial and non-financial factors of this concept by combining two methods, namely the Balanced Scorecard (BSC) and Data Envelopment Analysis (DEA).

Objectives: The main goal of the research in the paper is to show that certain deficiencies in the independent application of each method are eliminated by combining these methods.

Methods/Approach: The paper combines two methods, BSC and DEA, to measure the relative efficiency of all branches of a bank in Serbia.

Results: Results confirmed that the combined use of the named methods facilitates measurement of organizational efficiency by using both financial and non-financial indicators.

Conclusions: The paper shows that it is possible to achieve synergetic effects in the evaluation of organizational efficiency in the banking sector if BSC is applied first, to define goals within four perspectives, and then four DEA models are developed to measure efficiency in each perspective.

variation is no longer sufficiently recorded in the tree rings and an-other climatic variable has to be used for successful cross-dating. As was illustrated using the dataset VP, the combined method is not specifically limited to the use of temperature measurements. Any reliable dated climatic instrumental record can be used instead. Therefore, when a tree-ring series loses the sensitivity to the originally selected climate variable, it can be replaced by another available alternative. Adverse (cool, rainy and short) growing seasons in temperature limited environments may

Abstract

This paper proposes the combination of the THESEUS multi-criteria sorting method with an evolutionary optimization-based preference-disaggregation analysis. The main features of the combined method are studied by performing an extensive computer experiment that explores many models of preferences and sizes of problems as well as different degrees of decision-maker involvement. As a result of the experiment, the effectiveness of the combined framework and the importance of the decision-maker’s involvement are characterized.

Abstract

This paper combines methods of argumentation theory and artificial intelligence to extend existing work on the dialectical structure of crossexamination. The existing method used conflict diagrams to search for inconsistent statements in the testimony of a witness. This paper extends the method by using the inconsistency of commitments to draw an inference by the ad hominem argumentation scheme to the conclusion that the testimony is unreliable because of the bad ethical character for veracity of the witness.

Abstract

The use of cartographic sources and methods are the basic tools of historical geography. One of the main research trends in this field is the analysis of the spatial layout and number of old settlement units. The confrontation of maps with historical data allows the drawing of a town’s area at a certain time to be studied. The retrogression (R) and progression (P) methods that are currently used are imperfect and the model created (map) is usually incomplete and its reliability is limited. In the author’s opinion, the joining of retrogression and progression (a new method; combined – K)1 increases the quality of cartographic reconstruction of natural and cultural landscapes. The use of basic mathematical methods from the scope of set operations means the component reliability of the researched cartographic model can be varied because the common part of the retrogression and progression cartographic model represents mutual verification of source data. Quantitative effectiveness assessments of retrogression (R), progression (P) and the combined method (K) can be made for countable elements (e.g. buildings). As part of the conducted study, the effectiveness of separate methods was calculated: R = 76% for retrogression, P = 59% for progression and K = R ∪ P = 85% for the combined method. The mutual verification of the methods (R ∩ P) included 45% of residential buildings. The author describes the proposition of a new method and the course of verification research.