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The purpose of this paper is to show an efficient method for the detection of signs of early lung cancer. Various image processing algorithms are presented for different types of lesions, and a scheme is proposed for the combination of results.

A computer aided detection (CAD) scheme was developed for detection of lung cancer. It enables different lesion enhancer algorithms, sensitive to specific lesion subtypes, to be used simultaneously. Three image processing algorithms are presented for the detection of small nodules, large ones, and infiltrated areas. The outputs are merged, the false detection rate is reduced with four separated support vector machine (SVM) classifiers. The classifier input comes from a feature selection algorithm selecting from various textural and geometric features. A total of 761 images were used for testing, including the database of the Japanese Society of Radiological Technology (JSRT).

The fusion of algorithms reduced false positives on average by 0.6 per image, while the sensitivity remained 80 per cent. On the JSRT database the system managed to find 60.2 per cent of lesions at an average of 2.0 false positives per image. The effect of using different result evaluation criteria was tested and a difference as high as 4 percentage points in sensitivity was measured. The system was compared to other published methods.

The study described in the paper proves the usefulness of lesion enhancement decomposition, while proposing a scheme for the fusion of algorithms. Furthermore, a new algorithm is introduced for the detection of infiltrated areas, possible signs of lung cancer, neglected by previous solutions.

This paper aims to propose a vacuum-assisted post-processing method for use in binder jetted technology. The method is based on six key technological parameters and uses standard, commercially available consumables to achieve improvement in tensile strength, as well as the microstructure and porosity of the infiltrated matrix.

Six key technological parameters were systematically varied as factors on three levels, using design of experiment, i.e. definitive screening design. Surface response methodology was used to optimize the process and yield optimal tensile strength for the given range of input factors. Thus obtained, the optimized factor settings were used in a set of confirmation runs, where the result of optimization was experimentally confirmed. To confirm improvement in microstructure of the infiltrated matrix, SEM analysis was performed, while the reduction of porosity was analyzed using mercury porosimetry.

The obtained results indicate that, compared to its conventional counterpart, the proposed, optimized infiltration method yields improvement in tensile strength which is significant from both the statistical and engineering point of view, while reducing porosity by 3.5 times, using only standard consumables. Scanning electron microscopy examination of fractured specimens’ micrographs also revealed significant morphological differences between the conventional and proposed method of post-processing. This primarily reflects in higher surface area under hardened epoxy infiltrate, which contributes to increased load capacity of specimen cross-section.

At the present stage of development, the most important limitation of the proposed method is the overall size of models which can be accommodated in standard vacuum impregnation units. Although, in this study, the infiltration method did not prove statistically significant, further investigation is required with models of complex geometry, various sizes and mass arrangements, where infiltration would be more challenging and could possibly result in different findings.

The most important practical implication of this study is the experimentally verified result of optimization, which showed that tensile strength and matrix microstructure can be significantly improved, using just standard consumables.

Improved strength contributes to reduction of material consumption, which, in a longer run, can be beneficial for environment protection and sustainable development.

Based on literature review, there have been no previous investigations which studied the tensile strength of infiltrated specimens through design of experiment, which involved specimen preheating temperature, level and duration of vacuum treatment of infiltrate mixture and infiltrated specimens and infiltration method.

The purpose of this paper is to design and develop a model for testing watertightness of rainscreen walls.

A test model was developed to determine the time to achieve equalisation and tightness rate of the rainscreen under investigation. Other tests include the distribution of wind loads to each rain screen layer, with the amount of water infiltrating into the cavity and the tightness rates.

It is found that the cavity must be compartmentalized, separating zones with different pressures. Vertically, corners and lateral stripes, 2 or 3m wide, must necessarily be compartmentalized. Horizontally, it is very convenient to compartmentalize the cavities of each floor, or at least every two floors (maximum 6m). When a cavity is not compartmentalized and tight, there will be air currents moving inside the cavity, and therefore the amount of infiltrated water through vents and joints will increase.

The paper demonstrates its value by developing a model to investigate the watertightness of rainscreen walls.

The purpose of this paper is to characterize and evaluate a new 3D‐printing process based on Poly(methyl methacrylate) (PMMA).

A benchmark part and standard parts were designed, printed by a 3D‐printer and characterized.

3D printed PMMA parts have a tensile strength of 2.91 MPa and a modulus of elasticity of 223 MPa. The mechanical properties can be improved by infiltrations with epoxy (tensile strength: 26.6 MPa, modulus of elasticity: 1,190 MPa). The surface quality of the parts can be improved by infiltration with wax for usage as lost models. The minimum feature size is 0.3 mm.

The PMMA‐based 3D printing process can be used for manufacturing concept models, functional parts and lost models for investment casting.

This is the first paper investigating a PMMA‐based 3D printing process.

With the rapid development of Internet technology, cybersecurity threats such as security loopholes, data leaks, network fraud, and ransomware have become increasingly prominent, and organized and purposeful cyberattacks have increased, posing more challenges to cybersecurity protection. Therefore, reliable network risk assessment methods and effective network security protection schemes are urgently needed.

Based on the dynamic behavior patterns of attackers and defenders, a Bayesian network attack graph is constructed, and a multitarget risk dynamic assessment model is proposed based on network availability, network utilization impact and vulnerability attack possibility. Then, the self-organizing multiobjective evolutionary algorithm based on grey wolf optimization is proposed. And the authors use this algorithm to solve the multiobjective risk assessment model, and a variety of different attack strategies are obtained.

The experimental results demonstrate that the method yields 29 distinct attack strategies, and then attacker's preferences can be obtained according to these attack strategies. Furthermore, the method efficiently addresses the security assessment problem involving multiple decision variables, thereby providing constructive guidance for the construction of security network, security reinforcement and active defense.

A method for network risk assessment methods is given. And this study proposed a multiobjective risk dynamic assessment model based on network availability, network utilization impact and the possibility of vulnerability attacks. The example demonstrates the effectiveness of the method in addressing network security risks.

The paper aims at expanding knowledge on the presence of organized criminal groups in public contract procurement in the south of Italy. It seeks to highlight how the capabilities of law enforcement agencies could be enhanced by means of criminological models.

The paper sets out a criminological model with which to assess the general and specific risks of the infiltration of public procurement in the south of Italy by organized crime (OC).

According to the geographical risk assessment, infiltration by OC of public procurement seems to be widespread in some areas of south Italy, especially Sicily, Calabria and Campania. On the other hand, the specific risk may increase according to certain features of the company and its representatives, the value of the contract, the low specialization of the activities required by the public contract.

The paper describes a criminological model with which to assess the general and specific risk of infiltration by OC of public procurement in south Italy.

Metal‐based powder systems for selective laser sintering applications provide flexibility in the part geometry and promise a high quality profile regarding their material technologies characteristic. In this field of application, materials have to fulfil high demands on their properties already in the conceptual phase of development. For the integration of selective laser sintered parts into the development process, determining their properties using material engineering methods is absolutely essential. This paper concerns with the methods of material analysis, the particular material properties of sintered metals and finally with the description of the properties of the powder systems EOS DirectSteel 20 and 3D Laser Form ST100 in comparison to conventional materials used in automotive engines and power trains.

Information and communication in times of war is an area that has been much written about, but one which has not often been treated as a topic in its own right from an information science perspective. The national liberation struggles of the second half of the 20th century offer possibilities for the development of an information and communication model, incorporating data on a range of covert and overt information and communication activities by both sides in the conflict. The model takes account of such activities as scouting, secret communication, propaganda, misinformation campaigns, censorship, intelligence gathering and collating, and other aspects of information‐related activity. It offers a capacity to structure this knowledge, indicates gaps and concentrations in activity, and permits audit and assessment of information‐related activity in the struggle. It is intended to be capable of providing perspectives on information warfare in other contexts, although this aspect is not explored here.

Chaos theory is about to invade the thinking and vocabulary of practising managers and management academics. It will mark the major breakthrough in the 1990s, just as systems theory represented the great step forward three decades ago. Indeed, it may be regarded as a natural extension of systems theory. Provides an explanation of what chaos theory means in the light of some important scientific developments which may now be viewed as superseded. Explores the connection with management thinking through a number of major management writers who display an implicit awareness of chaos. A discussion considers the interrelationship between order and disorder, and the significance for creativity and leadership in organizations. Managers need to thrive on chaos, and to revamp some deeply entrenched attitudes if they are to succeed in the midst of an operating environment that is less stable and predictable.