Particle In-Flight and Coating Properties of Fe-Based Feedstock Materials Sprayed with Modern Thermal Spray Systems

New developments in the field of thermal spraying systems (increased particle velocities, enhanced process stability) are leading to improved coatings. Innovations in the field of feedstock materials are supporting this trend. The combination of both has led to a renaissance of Fe-based feedstocks. Using modern APS or HVOF systems, it is now possible to compete with classical materials for wear and corrosion applications like Ni-basis or metal-matrix composites. This study intends to give an analysis of the in-flight particle and spray jet properties achievable with two different modern thermal spraying systems using Fe-based powders. The velocity fields are measured with the Laser Doppler Anemometry. Resulting coatings are analyzed and a correlation with the particle in-flight properties is given. The experiments are accompanied by computational fluid dynamics simulations of spray jet and particle velocities, leading to a comprehensive analysis of the achievable particle properties with state-of-the-art HVOF and APS systems.     

Modeling the Direct Synthesis of Dimethyl Ether using Artificial Neural Networks

Artificial neural networks (ANNs) are designed and implemented to model the direct synthesis of dimethyl ether (DME) from syngas over a commercial catalyst system. The predictive power of the ANNs is assessed by comparison with the predictions of a lumped model parameterized to fit the same data used for ANN training. The ANN training converges much faster than the parameter estimation of the lumped model, and the predictions show a higher degree of accuracy under all conditions. Furthermore, the simulations show that the ANN predictions are also accurate even at some conditions beyond the validity range.     

Reducing model checking commitments for agent communication to model checking ARCTL and GCTL*

Social commitments have been extensively and effectively used to represent and model business contracts among autonomous agents having competing objectives in a variety of areas (e.g., modeling business processes and commitment-based protocols). However, the formal verification of social commitments and their fulfillment is still an active research topic. This paper presents CTLC⁺ that modifies CTLC, a temporal logic of commitments for agent communication that extends computation tree logic (CTL) logic to allow reasoning about communicating commitments and their fulfillment. The verification technique is based on reducing the problem of model checking CTLC⁺ into the problem of model checking ARCTL (the combination of CTL with action formulae) and the problem of model checking GCTL^* (a generalized version of CTL^* with action formulae) in order to respectively use the extended NuSMV symbolic model checker and the CWB-NC automata-based model checker as a benchmark. We also prove that the reduction techniques are sound and the complexity of model checking CTLC⁺ for concurrent programs with respect to the size of the components of these programs and the length of the formula is PSPACE-complete. This matches the complexity of model checking CTL for concurrent programs as shown by Kupferman et al. We finally provide two case studies taken from business domain along with their respective implementations and experimental results to illustrate the effectiveness and efficiency of the proposed technique. The first one is about the NetBill protocol and the second one considers the Contract Net protocol.     

Oxidative stabilities of mango kernel fat fractions produced by three-stage fractionation

Trans-free mango kernel fat stearins and oleins were produced by three-stage acetone fractionation to achieve the sufficient utilization of fat. Fatty acid and triacylglycerol compositions, slip melting points, iodine values, micronutrient (tocopherol, sterol, and squalene) levels, as well as oxidative stability indexes of the fractions were analyzed to evaluate their qualities. The most abundant fatty acids in the stearins were saturated fatty acids (57.3–65.1%, mainly including palmitic, stearic, and arachidic acids), and the major triacylglycerols were symmetrical monounsaturated types (78.3–93.7%). The unique properties make the stearins show highest slip melting points 34.7–38.3°C and oxidative stability indexes (12.0–14.2 h), and very suitable for the manufacturing of hard chocolate fats. The oleins contained high percentages of monounsaturated (48.3–53.7%) and polyunsaturated fatty acids (7.8–8.5%). Their oxidative stability indexes (6.3–6.7 h) were lower than the stearins but higher than common commercial oils. About 85.2% of tocopherol, 99.2% of sterol, and 79.2% of squalene were transferred to the liquids after fractionation, which could improve their antioxidant abilities. Further multiple linear regression analyses between oxidative stability indexes and fat compositions revealed that polyunsaturated fatty acid and sterol were the main factors that affect the oxidative stabilities of the fractions. The results suggested that the moderated refining techniques should be developed to retain more sterol to improve the oxidative stabilities and nutritive values of the fats.     

DESIGN OF A LOW-COST MICROCONTROLLER-BASED FUNCTIONAL ELECTRONIC STIMULATION DEVICE FOR DROP FOOT CORRECTION

Correction of drop foot is normally achieved by electrical stimulation of the common peroneal nerve by sending a series of pulses at a given frequency and duration. This article presents the design of a low-cost, programmable, portable, and high performance stimulator, designed at the Near East University. The stimulator, called the NEU-Stim, has been designed to correct the drop foot problems. For this purpose, a foot sensor, microcontroller, and electrodes are used in the design of the stimulator. The frequency, duty cycle, and the amplitude of the output waveform can easily be controlled using switches. The device is currently in experimental stage, and because of its low-cost it should find applications in developing countries after it has been completely assessed. Preliminary results on patients have shown that the device can correct the drop foot, and help patients to walk faster and more comfortably.     

Modeling improvements in booster seat use: a discrete choice conjoint experiment

Automobile crashes are the leading cause of death in children aged 1–14 years. Many children, however, are not properly restrained in safety seats that reduce serious injury and death. This study used a discrete choice conjoint experiment to study factors influencing the decision to use booster seats. Parents of 1714 children aged 4–9 years from nine Canadian provinces completed choice tasks presenting experimentally varied combinations of 15 4-level booster seat promotion attributes. Latent class analysis yielded three segments of parents. The choices of the Benefit Sensitive segment (50%) were most sensitive to the injury prevention benefits of booster seats. The choices of parents in the Context Sensitive segment (33.5%) were more likely to be influenced by installation complexity, oppositional behavior, and the prospect that their child may be teased for riding in booster seats. Parents in the High Risk segment (16.5%) were younger, less educated, and less knowledgeable about vehicle safety legislation. They anticipated fewer benefits, expected more barriers and were less likely to use booster seats. Simulations suggest that consistent enforcement coupled with advertising focusing on injury prevention and the use of booster seats by other parents would increase adoption.     

Thought control strategies in acute stress disorder

Relapse after transplant for malignant lymphomas remains the main cause of treatment failure. Most conditioning regimens contain total body irradiation (TBI). We investigated the toxicity and efficacy of an intensified chemotherapy conditioning regimen without TBI in patients with relapsed or high-risk malignant lymphoma who had received prior radiation therapy and were therefore not eligible for TBI. Twenty patients with a median age of 38 (18-56) and relapsed or high-risk malignant non-Hodgkin's lymphoma (NHL, n = 16) or Hodgkin's disease (HD, n = 4) underwent high-dose chemotherapy consisting of busulfan (16 mg/kg), cyclophosphamide (120 mg/kg) and etoposide 30 mg/kg (n = 8) or 45 mg/kg (n = 12) followed by peripheral stem cell support (n = 14), autologous bone marrow (n = 3), allogeneic (n = 2) or syngeneic (n = 1) transplantation. All but two had chemosensitive disease before high-dose chemotherapy. The main toxicity -- according to the Bearman score -- was mucositis II in 18 (90%) patients; five patients (25%) suffered a grade I hepatic toxicity. GI toxicity I occurred in three (15%) and renal toxicity I in two patients (10%). Sixty percent of the patients developed transient dermatitis with erythema and three of them (15%) had skin desquamation; one patient experienced asymptomatic pancreatitis. Toxicity was slightly higher in patients treated with 45 mg/kg etoposide. One patient (5%) died of treatment-related venoocclusive disease. After a median follow-up of 50 months (24-84) the disease-free and overall survival were 50% and 55%. One of the nine relapsing patients developed secondary AML 18 months after transplant. High-dose busulfan, cyclophosphamide and etoposide is an effective regimen resulting in long-term disease-free survival in 50% of patients with relapsed malignant lymphoma and prior radiation therapy. The toxicity is moderate with a low treatment-related mortality (5%).     

Milling as a method of surface pre-treatment of steel for adhesive bonding

The paper analyses the impact of mechanical milling pre-treatment parameters on adhesive joint strength. Comparison of surface roughness of adherends after milling and its effect on adhesive joint strength is analysed in strength tests. The tests were performed on C45 structural steel specimens, which were subjected to machining at different parameters, with two types of milling cutters. Adherends were degreased prior to adhesive joining. Two types of end mills used in tests were NFPaφ20 high-speed steel cutter and R390-020B20-11L indexable milling cutter. The machining was carried out at three cutting speeds: 0.05, 0.15 and 0.30 mm/tooth. Adherends were joined with an adhesive composition of Epidian 57 epoxy resin and Z-1 curing agent.     

Identification and safety evaluation of Bacillus species occurring in high numbers during spontaneous fermentations to produce Gergoush, a traditional Sudanese bread snack

Gergoush is a naturally fermented Sudanese Bread snack produced in three fermentation steps (primary starter, adapted starter and final dough), followed by three baking steps for a half to one hour at above 200 °C. This study examines the microbiota of two sets of fermentations performed at a traditional production site in Khartoum, Sudan in 2006 and 2009, respectively. In 2006 four different milk/legume based primary starters (faba bean, chick pea, lentil and white bean) were sampled in order to enumerate and identify the Bacillus at species or group level. In 2009 specific focus was on the enumeration and safety evaluation of the dominant Bacillus cereus group species occurring during various Gergoush productions (including the three fermentations steps and after baking). In 2006, the primary starters contained Bacillus spp. in the order of between 7.7 and 8.1 log₁₀ CFU/g. Species identifications were performed by M13-PCR typing using the Escherichia coli phage M13 derived primer PM13 combined with internally transcribed 16-23S rRNA PCR, 16S rRNA gene and gyrA or gyrB gene sequencing, and selected phenotypic tests. Depending on the legume used, 40-68% of the isolates were identified as B. cereus sensu lato, 16-27% as Bacillus licheniformis, 8-32% as Bacillus subtilis and 4-20% as Bacillus sonorensis. During the second set of fermentation trials performed in 2009, the Bacillus spp. and B. cereus occurred in numbers of between 7.7-9.9 and 6.1-7.8 log₁₀ CFU/g, respectively, while no bacteria were detected after baking. A total of 180 B. cereus sensu lato isolates from four different primary starters, adapted starters and final doughs were further identified as B. cereus sensu stricto (118 isolates) and Bacillus thuringiensis (62 isolates). The safety of Gergoush was evaluated based on the counts and toxin gene profiles of the dominant B. cereus species. Considering that no bacteria survived the baking process, and that the cereulide synthetase gene cesB involved in the production of the heat stable emetic toxin cereulide was not detected in any of the investigated B. cereus isolates, the results indicate, that Gergoush produced at the traditional production site is safe for human consumption. This study is the first to identify the Bacillus of Gergoush to species level, and it is the first to perform a safety evaluation of the product, based on the dominant B. cereus species.     

Reverse Engineering of Mobile Banking Applications

Software reverse engineering is the process of analyzing a software system to extract the design and implementation details. Reverse engineering provides the source code of an application, the insight view of the architecture and the third-party dependencies. From a security perspective, it is mostly used for finding vulnerabilities and attacking or cracking an application. The process is carried out either by obtaining the code in plaintext or reading it through the binaries or mnemonics. Nowadays, reverse engineering is widely used for mobile applications and is considered a security risk. The Open Web Application Security Project (OWASP), a leading security research forum, has included reverse engineering in its top 10 list of mobile application vulnerabilities. Mobile applications are used in many sectors, e.g., banking, education, health. In particular, the banking applications are critical in terms of security as they are used for financial transactions. A security breach of such applications can result in huge financial losses for the customers as well as the banks. There exist various tools for reverse engineering of mobile applications, however, they have deficiencies, e.g., complex configurations, lack of detailed analysis reports. In this research work, we perform an analysis of the available tools for reverse engineering of mobile applications. Our dataset consists of the mobile banking applications of the banks providing services in Pakistan. Our results indicate that none of the existing tools can carry out the complete reverse engineering process as a standalone tool. In addition, we observe significant differences in terms of the execution time and the number of files generated by each tool for the same file.