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A global upsurge in antibiotic-resistant Acinetobacter baumannii requires supervised selection of biocides and disinfectants to avert nosocomial infections by reducing its spread. Moreover, inadequate and improper biocides have been reported as a contributing factor in antimicrobial resistance. Regardless of the manner of administration, a biocidal concentration that does not kill the target bacteria creates a stress response, propagating the resistance mechanisms. This is an essential aspect of the disinfection programme and the overall bio-contamination management plan. Knowing the mechanisms of action of biocides and resistance modalities may open new avenues to discover novel agents. This review describes the mechanisms of action of some biocides, resistance mechanisms, and approaches to study susceptibility/resistance to these agents. [ABSTRACT FROM AUTHOR]

Highlights • A non-contact and automated ballast geometry inspection method was developed. • The new method performs more accurate and less time-consuming inspection of ballast conditions. • A new railway ballast layer geometry index was developed. • Using the new index, an improved/optimized maintenance approach was established. • It prioritizes required repair actions and provides more accurate allocation of machinery. Abstract Ballast layer Geometry condition is an important criterion in the railway track maintenance since the track stability strictly depends on the ballast geometry. Currently, a visual inspection is a method of monitoring ballast layer geometry which is considerably costly and time-consuming. Addressing the limitations of the current ballast maintenance approach, a new ballast layer geometry index was established, using an automated measurement system. This index is a function of deficits and excess of ballast in the track. A new maintenance approach was developed based on the new index, providing the possibility of quickly measuring ballast profile for faster and more accurate ballast maintenance. To examine the practicability and applicability of the new method/index, the results of a comprehensive field measurement were used. By illustrating the effectiveness of the new index in the field, it was shown that the new approach can significantly improve the current maintenance methods. It provides the possibility of fast and easy recording ballast layer geometry and maintaining optimum ballast conditions. [ABSTRACT FROM AUTHOR]

• Structure-borne noise (SBN) is an important concern for building residents. • A numerical model based on Finite Element Method (FEM) theory was developed to simulate SBN. • Incremental Vibration Analysis (IVA) was proposed to investigate the impact of frequency content and vibration amplitude on the generation of SBN. • The reliability index was used to develop a safety threshold for buildings against SBN. • The propagation of SBN depended on the vibrations induced by trains under the building foundation. Today, the need for development of metro lines in crowded urban environments is inevitable. Construction and operation of metro generally have adverse side effects (such as noise and vibration) on residents of buildings adjacent to the metros. Based on various published reports, train-induced Structural Borne Noise is mostly annoying, causing people discomfort. Addressing this issue, probabilistic assessment of train-induced annoyance level in buildings adjacent to subway lines was made in this study. For this purpose, a numerical model of typical buildings in vicinity of a subway line was developed. The model was validated by field tests performed in this study. Nine different sites along metro lines were selected to obtain vibration characteristics of train-induced accelerations received by the metro adjacent building foundations. Various possible vibration time histories were applied to the foundation of the model, using an Incremental Vibration Analysis. At each step of the analysis, the Sound Pressure Level in the building stories were obtained and compared with the limitations proposed by the Federal Railroad Administration. Using the results obtained, the probability of the Sound Pressure Level exceeding the allowable limits was derived. In this regard, a reliability index was obtained. Based on the reliability index, the propagation level of the impermissible Structure-Borne Noise in different stories of buildings was presented as a function of number of the building stories and the peak ground accelerations. Accuracy of the proposed function was illustrated by applying it to eight different sites, indicating the accuracy of more than 83%. [ABSTRACT FROM AUTHOR]

Ballast plays an important role in the stability of railway track systems. The effectiveness of the ballast in maintaining the track stability is very much dependent on its mechanical conditions. The available ballast maintenance approaches are mainly based on only track geometry conditions (such as track profile) which do not sufficiently reflect the ballast mechanical behaviors. That is, the ballast potential of degradation (i.e., ballast long term behaviors) has been omitted. This makes the effectiveness of the current ballast maintenance approach questionable, indicating a need for a more comprehensive and effective ballast conditions assessment technique. In response to this need, two ballast condition indices based on ballast geometry degradation (BGI) and the level of ballast fouling (BFI) as the main indicators of ballast mechanical behavior were developed. The BGI is a function of the standard deviations of track alignment, unevenness and twist. The BFI was developed based on the data obtained from the ground penetration radar (GPR). Making use of the new indices, a more reliable maintenance algorithm was developed. Through illustrations of the applicability of the new maintenance algorithm in a railway line, it was shown that the new algorithm causes a considerable improvement in the maintenance effectiveness and an increase in the life cycle of railway tracks by making more effective allocation of resources and more accurate maintenance planning. [ABSTRACT FROM AUTHOR]

Construction and operation of subways in crowded zones cause structure borne noise (SBN) which is sometimes annoying to the residents of nearby buildings. This is a serious challenge in the development of subways in large cities. Although various methods have been proposed to protect buildings against SBN, the amount of train-induced vibrations which cause impermissible SBN is not clearly known. Since train induced vibration is a criterion in the design and construction of subways, there is a need to find correlations between train-induced vibrations and SBN in order to take SBN into the subway and buildings design approaches. In response to this need, influences of train-induced vibration on SBN were studied in this research, leading to drive conditions for safety of buildings against train induced structure borne noise. For this purpose, a vibroacoustic model of building was developed and validated, using results of field tests carried out in this research. Buildings parameters were classified based on their structural and non-structural properties. Through parametric analysis of the model, effects of building structural and acoustic parameters on SBN were investigated. A prediction model was developed by which the allowable amount of train induced vibration acceleration beneath building foundations as a function of building conditions is derived. The model was used as a guideline for design and construction of safe buildings against SBN. The applicability and effectiveness of the results/model were illustrated by several field tests. • Structure borne noise (SBN) is important concern of buildings residents. • Numerical model based on FEM theories was developed to simulate SBN. • Influencing levels of structural/acoustical parameters of building on SBN were obtained. • Prediction model was developed to assess safety of buildings against train-induced SBN. • Improvement of current codes for design of building adjacent to subways was proposed. [ABSTRACT FROM AUTHOR]

Due to its competitive advantages and mitigation of global climate change, sustainability development has become a center of attention in the manufacturing society to improve production processes. Scant research exists on the three pillars of sustainability ― economy, environment, and society ― in production frameworks through the lens of process improvement tools such as lean and six-sigma. Based on lean six-sigma, this paper develops a sustainable lean production framework (SLPF) for manufacturing companies supported by the theory of practice-based view. Since a high portion of production frameworks failed to reach the sustainability goals in the implementation, we use practitioners' and scholars' perspectives to build a framework including five stages and fifteen steps. To validate the framework, we empirically apply practitioners' opinions using the Delphi method. Moreover, we experimentally verify the framework by implementing it in a cookware manufacturing company. The result showed that the proposed framework can significantly improve sustainability pillars, e.g., after an investment of $10,212, our case implementation was improved in the economy by $120,142 saving per year, the environment by reducing 257.14 tonnes CO 2 per year and the society by minimizing 48 safety incidents per year, and 24 worker-absence per year. The proposed framework and the three pillars of sustainability ― economy, environment, and society. Image 1 • This research develops a sustainable lean production framework (SLPF). • The Delphi method empirically validated SLPF. • A case implementation experimentally verified SLPF. • Quantitative results showed that SLPF is beneficial to sustainability developments. [ABSTRACT FROM AUTHOR]

In this paper, we study the massive Dirac equation with the presence of the Morse potential in polar coordinate. The Dirac Hamiltonian is written as two second-order differential equations in terms of two spinor wavefunctions. Since the motion of electrons in graphene is propagated like relativistic fermionic quasi-particles, then one is considered only with pseudospin symmetry for aligned spin and unaligned spin by arbitrary k. Next, we use the confluent Heun's function for calculating the wavefunctions and the eigenvalues. Then, the corresponding energy spectrum obtains in terms of N and k. Afterward, we plot the graphs of the energy spectrum and the wavefunctions in terms of k and r , respectively. Moreover, we investigate the graphene band structure by a linear dispersion relation which creates an energy gap in the Dirac points called gapped graphene. Finally, we plot the graph of the valence and conduction bands in terms of wavevectors. • Analytical solution of energy spectrum for relativistic fermionic quasiparticles. • Calculation of two spinor wavefunctions by using the confluent Heun's function. • Obtaining the graphene band structure by a linear dispersion relation. • calculation of energy gap in the Dirac points called gapped graphene. [ABSTRACT FROM AUTHOR]