Fuzzy Bayesian reliability and availability analysis of production systems

To have effective production planning and control, it is necessary to calculate the reliability and availability of a production system as a whole. Considering only machine reliability in the calculations would most likely result unmet due dates. In this study, a new modelling approach for determining the reliability and availability of a production system is proposed by considering all the components of the system and their hierarchy in the system structure. Components of a production system are defined as production processes; components of the processes are defined as sub-processes. In this hierarchical structure we could model all kinds of failures such as material and supply, management and personnel, and machine and equipment. In the analysis, a fuzzy Bayesian method is used to quantify the uncertainties in the production environment. The suggested modelling approach is illustrated on an example. In the example, also a separate reliability and availability analysis is conducted which only considered machine failures, and the results of both analyses are compared.     

Mobile multi-view object image search

High user interaction capability of mobile devices can help improve the accuracy of mobile visual search systems. At query time, it is possible to capture multiple views of an object from different viewing angles and at different scales with the mobile device camera to obtain richer information about the object compared to a single view and hence return more accurate results. Motivated by this, we propose a new multi-view visual query model on multi-view object image databases for mobile visual search. Multi-view images of objects acquired by the mobile clients are processed and local features are sent to a server, which combines the query image representations with early/late fusion methods and returns the query results. We performed a comprehensive analysis of early and late fusion approaches using various similarity functions, on an existing single view and a new multi-view object image database. The experimental results show that multi-view search provides significantly better retrieval accuracy compared to traditional single view search.     

Automated construction of fuzzy event sets and its application toactive databases

Fuzzy sets and fuzzy logic research aims to bridge the gap between the crisp world of maths and the real world. Fuzzy set theory was applied to many different areas, from control to databases. Sometimes the number of events in an event-driven system may become very high and unmanageable. Therefore, it is very useful to organize the events into fuzzy event sets also introducing the benefits of fuzzy set theory. All the events that have occurred in a system can be stored in event histories which contain precious hidden information. We propose a method for automated construction of fuzzy event sets out of event histories via data mining techniques. The useful information hidden in the event history is extracted into a matrix called sequential proximity matrix. This matrix shows the proximities of events and it is used for fuzzy rule execution via similarity based event detection and construction of fuzzy event sets. Our application platform is active databases. We describe how fuzzy event sets can be exploited for similarity based event detection and fuzzy rule execution in active database systems     

Study on the behavior of the trace metal and macro minerals in Mytilus galloprovincialis as a bioindicator species: the case of Marmara Sea, Turkey

Sea food is a major source of animal protein. Marine foods are very rich sources of mineral components. The total content of minerals in the raw flesh of marine fish and invertebrates is in the range of 0.6–1.5% wet weight. The contents of Na, K, Ca, Mg and P are up to 1 mg/100 g, whereas those of Fe, Zn, I are less than 1 mg/100 g. Mussels (Mytilus galloprovincialis) were investigated for macro and trace element composition throughout the year. Ranges of moisture, ash, protein and fat contents were 79.76–87.46 g/100 g, 1.06–2.06 g/100 g, 7.28–12.65 g/100 g and 0.33–3.49 g/100 g, respectively. While the highest protein and fat values were found in the summer (July–August), the highest moisture and ash contents were found in the winter (December–January). The contents of highest Na, K, Ca were found in the summer. Cadmium, lead and copper were found to be below the legislative limits throughout year. High levels of mercury were found in January and October. It should be discussed whether mussel may provide an alternative source of mineral for healthy nutrition.     

The use of polyacrylamide-aluminosilicate composites for thorium adsorption

The adsorption of Th⁴⁺ ions was studied on composites of polyacrylamide (PAAm) with montmorillonite (Mt), clinoptilolite (Z) and zeolite Y (ZY), and after phytic acid (Phy) modification.The monolayer adsorption capacity was 0.33 and 0.65 mol kg^? 1 for PAAm-Mt and PAAm-Mt-Phy, 0.07, 0.21 and 0.60 mol kg^? 1 for Z, PAAm-Z and PAAm-Z-Phy, and 0.74, 0.89 and 1.18 mol kg^? 1 for ZY, PAAm-ZY and PAAm-ZY-Phy. The enthalpy and entropy changes were positive for all adsorbents. The adsorption kinetics followed the pseudo-second order model indicating that the rate controlling step was chemical adsorption by ion exchange. The reusability tests for five uses proved that the PAAm-Mt and PAAm-Z were reusable and complete recovery of the adsorbed ions was possible. ZY and the composites modified with Phy were not reusable. The presence of foreign metal cations did not influence the Th⁴⁺ adsorption. The adsorbed Th⁴⁺ onto the columns was effectively recovered with diluted HNO₃.     

Electricity generation in microbial fuel cell systems with Thiobacillus ferrooxidans as the cathode microorganism

Microbial fuel cells (MFC) are systems that enable biochemical activities of bacteria to generate the electricity. These systems are of great interest because of their designs that enable biological activity in organic wastes to be transformed into direct electrical energy. In order to increase the commercial usage of MFCs, it is necessary to increase the power output of the system. So as to improve MFC performance, used material selection, the pH value of the used bacterial medium and the choice of the appropriate substrate are very important. In this study, oxidation bacteria Thiobacillus ferrooxidans on the cathode and mixed culture bacteria on the anode of MFC were used. Different anode and cathode pH values were examined in MFC. Best open circuit potential result (0.8 V) was obtained at anode pH 8 and cathode pH 2 conditions. In addition, three different substrates had been used in the anode. In the conditions of acetate the most stable and high valued curve was obtained. The open circuit potential had reached 0.726 V, and power density had reached 0.88 mW/cm².     

Natural-based polymers for antibacterial treatment of absorbent materials

In this study, polypropylene (PP) nonwoven fabric which can be used as topsheet layer of an absorbent hygienic product was modified by natural based antibacterial agents. Antibacterial herbal agents (cinnamaldehyde, geraniol, phenylethyl alcohol) were sprayed by ethanol or applied by means of polylactic acid (PLA) and polycyclohexene oxide (PCHO) based polymers prepared by three different chemical methods. Characterization of synthesized materials was conducted via thermogravimetric analysis (TGA), differential thermal analysis (DTA), and scanning electron microscopy–energy dispersive X–ray spectroscopy (SEM-EDX). Besides characterization, antibacterial and pH buffering performances of antibacterial polymers alone and on PP fabric were tested by antibacterial and pH tests. Effects of antibacterial treatments on air permeability and absorption period of nonwoven fabrics were also analyzed. According to the results, biopolymers changed the thermal stability of PP nonwoven fabric. Antibacterial performances can be ranked as cinnamaldehyde, geraniol, and phenylethyl alcohol from the best. Besides a slight decrease about liquid absorption performance, all of the treated topsheet fabrics are sufficient for an absorbent hygienic product. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48302.     

Primary retroperitoneal liposarcoma: a case report and review of the literature

We report a case of a 43 years old woman with a retroperitoneal liposarcoma located in the left iliac fossa. The condition was discovered because of the association of left flank pain, abdominal distention and persistent urinary infection with symptoms of vesical irritation. The diagnosis was suggested by intravenous pyelography (IVP), abdominal and pelvic ultrasonography (USG) and computed tomography (CT). Treatment was exclusively surgical. During a six-month follow-up, no recurrence was observed.     

A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(Ⅳ), Se(Ⅵ)) at trace levels in natural lake and river water samples

A novel catalytic kinetic method is proposed for the determination of Se(Ⅳ), Se(Ⅵ), and total inorganic selenium in water based on the catalytic effect of Se(Ⅳ) on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the two calibration graphs are linear with a good correlation coefficient in the range 2-20 and 20-200 μg·L-1 of Se(Ⅳ) for the fixed-time method a...     

Acceleration of direct volume rendering with programmable graphics hardware

We propose a method to accelerate direct volume rendering using programmable graphics hardware (GPU). In the method, texture slices are grouped together to form a texture slab. Rendering non-empty slabs from front to back viewing order generates the resultant image. Considering each pixel of the image as a ray, slab silhouette maps (SSMs) are used to skip empty spaces along the ray direction per pixel basis. Additionally, SSMs contain terminated ray information. The method relies on hardware z-occlusion culling and hardware occlusion queries to accelerate ray traversals. The advantage of this method is that SSMs are created on the fly by the GPU without any pre-processing. The cost of generating the acceleration structure is very small with respect to the total rendering time.