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This paper presents the model for the identification of reference points on the lifetime curve of engineering systems. This curve commonly represents the increase and decline of failure in relation to time. A direct correlation between failure rate and costs is assumed in this paper, therefore, statistical and empirical analysis of costs provided reference points. This approach is used for positioning stages of the engineering system's lifetime with a minimal number of failures and costs, regardless of whether these are acceptable or not. The following three stages are usually identified: the beginning, the stationary part and the end of life. The boundaries between them are recognized on the basis of minimum total lifetime costs and on economic lifetime costs. Model is tested on the dozers, machines frequently used in the mining industry for the earthmoving operations, and which are characterized by high operating and maintenance costs. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical outcome of deantigenated equine bone (DEB) grafts in a series of patients treated with DEB at six months postaugmentation. Materials and Methods: One hundred DEB grafts were inserted in 81 patients between January 2004 and December 2006. Thirty‐two DEBs were blocks and 68 were granules (52 sinus lift and 16 guided bone regeneration [GBR] procedures performed). A total of 147 implants were inserted. A Pearson chi‐square test was used to detect any statistically significant correlation between the studied variables and early and/or late failures. Results: There were 6 early and 26 late graft failures and another 16 failures after prosthesis placement. The overall failure rate was 25% in the GBR procedures, 31.9% in sinus lift, and 54.3% with blocks, for a total complication rate of 39.5%. A statistically significant relation was detected with respect to graft type and early complications (p =.005), with a worse outcome for DEB blocks compared to granules. After provisional prosthesis restoration, 23 implants were lost, and another 41 failed after definitive prosthesis delivery, for an overall failure rate of 43.5%. The follow‐up period was 3 years after surgery. Conclusions: DEB grafting material had a very high rate of complications. Blocks had more than 50% failures, mainly in the immediate postoperative period. Other procedures such as GBR and sinus lift also showed more than 25% infections and resorption, and late failures (i.e., after‐implant placement) were also common. Our results show that DEB is less than ideal for crestal bone reconstruction. [ABSTRACT FROM AUTHOR]

Transportation public–private partnership (PPP) projects are long-term projects that usually break the status quo of public ownership. In fact, opposition to PPP projects stems from a variety of factors, such as political influence to favor certain interest groups and high toll prices. Close examination reveals that vulnerability to societal and political domains originates at certain individual points and creates a complex web of problems as it propagates through different socioeconomic and political levels and project stages. This article attempts to unveil such complex and problematic trends by analyzing ten failed transportation PPP projects to identify critical socioeconomic and political failure factors. Employing questionnaire surveys and path analysis, a failure-mechanism model is developed to depict all possible transportation PPP project vulnerabilities to the socioeconomic and political domains. This article's failure-mechanism model could act as a vulnerability-prediction model for transportation PPP practitioners in the public and private sectors, and it can help better understand socioeconomic and political issues’ impacts to transportation PPP projects. [ABSTRACT FROM AUTHOR]

Cloud applications often benefit from deployment on serverless technology Function-as-a-Service (FaaS), which may instantly spawn numerous functions and charges users for the period when serverless functions are running. Maximum benefit is achieved when functions are orchestrated in a workflow or function choreographies (FCs). However, many provider limitations specific for FaaS, such as maximum concurrency or duration often increase the failure rate, which can severely hamper the execution of entire FCs. Current support for resilience is often limited to function retries or try-catch, which are applicable within the same cloud region only. To overcome these limitations, we introduce rAFCL, a middleware platform that maintains reliability of complex FCs in federated clouds. In order to support resilient FC execution under rAFCL, our model creates an alternative strategy for each function based on the required availability specified by the user. Alternative strategies are not restricted to the same cloud region, but may contain alternative functions across five providers, invoked concurrently in a single alternative plan or executed subsequently in multiple alternative plans. With this approach, rAFCL offers flexibility in terms of cost-performance trade-off. We evaluated rAFCL by running three real-life applications across three cloud providers. Experimental results demonstrated that rAFCL outperforms the resilience of AWS Step Functions, increasing the success rate of entire FC by 53.45%, while invoking only 3.94% more functions with zero wasted function invocations. rAFCL significantly improves availability of entire FCs to almost 1 and survives even after massive failures of alternative functions. [ABSTRACT FROM AUTHOR]

Abstract The paper presents possibilities of application of selected regression methods (classification trees, support vector machines, K-nearest neighbours, artificial networks) for classification of sewers’ damages. Operational data from the time span 2006–2011 obtained from water utility were used for deterioration analysis. On the basis of the following independent variables, the modelling was carried out: diameter, depth, year of construction, material and season of damage’s occurring. The following kinds of damages were classified: corrosion, crack, longitudinal crack, displacement, unsealing, failure, collapse. The main aim of the paper was to check if prediction methodology could be useful for classification of different kinds of sewers’ damages. The obtained results pointed out that proposed classification methods are not appropriable in quality analysis of registered damages of sewers. Moreover, it is recommended for water and sewerage companies to register types of failures using unified notation which make easier preliminary classification before applying modelling approach. The calculations were performed in Statistica 13.1 software.

Piston is the most important part in internal combustion engine. During engine operation, piston experiences stress, pressure, temperature change resulting in mechanical and thermal fatigue failure. In addition, the seizure of pistons due to their contact with the piston rings, skirt and cylinder liners is among the major problem in internal combustion engines, posing a serious threat to the efficiency of the automobiles. Hence, the aim of this review paper is to provide an overview of distinct causes of piston failures and their preventive measures. Further, the tribological and mechanical properties (hardness, elastic modulus, coefficient of friction, roughness, wear rate) of different coatings deposited by various researchers on piston/cylinder liner/piston ring are summarized. These results help the researchers in selecting an appropriate coating material composition, coating process, and parameters for a particular piston/cylinder liner/piston ring material to enhance the life of piston system. So, that any unwanted damage of piston system due to stress, pressure, fatigue, wear and friction could be minimized. [ABSTRACT FROM AUTHOR]

This paper focuses on the possibility to identify via technical, verbal, and visual characteristics of the digital text, the authenticity or fictitiousness of Facebook profiles. It also attempts to shed light on the different motives behind the creation of fake profiles. The cases analyzed in this paper, through qualitative content analysis, emphasize the significance of the profile's authenticity in the eyes of Facebook users. The findings help distinguish between a fictitious identity and a "stolen" one. The findings also indicate that there are different types of fake profiles, and that these can be derived from a variety of motives ranging from business promotion to personal needs. The study concludes that there are a number of visual, verbal and interactive components that make it possible to assess the degree of authenticity or fictitiousness of a given profile. First, the content filled in the fields: personal details, the type of information that the profile owner chooses to share or keep discreet, the type of images and the extent to which they are used. Second, the degree of activity in the profile: the number of friends and the frequency of activity, such as being tagged in photos. Also, the study reveals that users have their own thoughts concerning what an authentic profile is, and they seek to create profiles that do not necessarily meet Facebook's narrow "authenticity" criteria. [ABSTRACT FROM AUTHOR]

This paper proposes an optimal sizing strategy for water storage reservoirs that takes into account the minimum allowed number of failure periods (measure of reliability) and the maximum allowed failure magnitude (measure of vulnerability). The optimization model follows the standard operating policy for reservoir release decision—as in typical design procedures that account for failure—and is compared to an alternative mixed-integer linear programming model that uses an open-loop release policy. Deterministic and implicit stochastic versions of the model are presented, which perform efficiently for several example problems, indicating that higher storage capacities are required for higher sustainability (more reliable and less vulnerable operation) and lower risk. [ABSTRACT FROM AUTHOR]

Mobile devices are well-known communication tools. People, especially young people, cannot go even one step without them. Technological advancements provide better features, but at the same time, such systems still face security risks. Protective layers do exist, but some systems are automated and engineered, while others rely on humans. This work begins with examining some critical points related to the weakest link in the security chain: the human factor. Errors are given in the view of the Swiss Cheese Model by emphasizing the role of latent conditions in "holes". We found that the Swiss Cheese Model has some limitations. In order to enhance it, we have used the Failure Mode and Effect Analysis risk matrix methodology. Thus, we represent its application on mobile devices to demonstrate that it can give us more accurate results by identifying the most critical points where manufacturers should focus on. This work is based on qualitative data, and it provides the basis for quantitative research. In the end, we suggest that in order to obtain more accurate findings, the Failure Mode and Effect Analysis can be further extended. [ABSTRACT FROM AUTHOR]

In order to be innovative, libraries need to experiment and attempt new things. Part of this is the possibility of making mistakes and having failures along the way. Librarians can learn from these mistakes and failures and become better informed for future initiatives. However, like many organizations libraries are often risk-averse and do not reward experimentation and often mistakes and failures are looked on negatively. This can lead to less innovation and less learning – both on the individual and on the organizational level. Library leaders should encourage experimentation and understand that in order to be innovative, mistakes will be made and some initiatives will not be successful Making mistakes and having failures should not automatically be seen as a negative as long as they are used as leaning opportunities. By making mistakes, librarians can learn and grow. With this gained knowledge they, and their libraries, can be brought closer to success in the future. [ABSTRACT FROM AUTHOR]

Start-ups is a hot topic around the world in general and Vietnam in particular. People in Vietnam and from all over the world are focusing and investing a lot on start-ups. There are many start up crowding programs in all over the world. However, the achievements from start-ups are not as high as expected, and those in Vietnam are not exceptions. The performance of Vietnamese startup companies is becoming a matter of great concerns, especially with high economical contribution, and even so, startups in Vietnam market have not achieved much success. Therefore, by using qualitative research method with conducting in-depth interviews with startup companies, this article is to find out current factors that Vietnamese startup companies faced and propose solutions to support the growth of their businesses. In addition, after investigating the factors and answers to those factors, there are opens up to further research from this paper which can help to facilitate this content in larger scale. [ABSTRACT FROM AUTHOR]

One of the issues faced by asset managers in the electric power industry is the condition and remaining life assessment of the high voltage (HV) assets. In contrast to other power equipment, transmission power cables are mainly subjected to corrective maintenance. To support the asset management of service aged transmission power cable circuits, this paper discusses an approach of integrated knowledge rules for condition-based maintenance based on laboratory investigations and field examples. There are very few recent publications on this subject in spite of aging power cable infrastructure; therefore, this paper aims at showing practical applications of condition-based maintenance of this important component of the transmission and distribution systems. [ABSTRACT FROM AUTHOR]

Deficiencies in performance in forensic science have led to the need for a statutory regulator with powers over standards and performance, investigation, compliance and enforcement. [ABSTRACT FROM AUTHOR]

Despite being widely implemented, sustainable urban drainage systems (SUDS) do not always function flawlessly. While SUDS have been tested extensively and seem to perform well on a laboratory or pilot scale, practitioners' experience is different: failures in SUDS occur regularly in practice, resulting in malfunctioning systems, water nuisance and high costs. To anticipate their malfunctioning, and thus to improve their performance, a better understanding of failures occurring in SUDS and their underlying causes is needed. Based on an explorative case-study approach, consisting of site visits and semi-structured interviews with urban water professionals, this study presents an inventory of technical failures in SUDS and an analysis of their root causes. In total, 70 cases in 11 Dutch municipalities have been documented. The results show that the interfaces between SUDS and other urban systems are prominent failure locations. In addition, we found that failures originate from the entire development process of SUDS, i.e., from the design, construction and user/maintenance phase. With respect to the causes underlying these failures, our results show that these are mainly socio-institutional in nature. These are valuable insights for both practitioners and scholars, contributing to a renewed socio-technical urban water system with more sustainable water management practices. HIGHLIGHTS This study analyzes the malfunctioning of SUDS in practice and identifies the causes underlying this malfunctioning.; We found that interfaces between SUDS and other urban systems are prominent failure locations.; The causes underlying these failures were mainly socio-institutional, rather than technical in nature.; Practitioners need to acquire new knowledge and develop their skills for the successful management of SUDS.;

Tendencies of sustainable development of transport, the use of alternative energy sources, and requirements to the reduction of the carbon footprint on all stages of life cycle on all levels of road transport have led to the increase of the share of the electric car both at the first registration and used vehicles. The appearance of a large amount of used modern electric cars on the market caused the necessity to develop the procedures of provision their technical operation both by requirements of rational use and provision of traffic safety. Research of the use of electric car Tesla Model S90D in conditions of Ukraine is carried out with certain indicators of environment and with different settings of car parameters. This provides an opportunity to understand how much the given model of the electric car is appropriate in exploitation in different conditions and also to determine which parameters of electric car settings fit the economic usage in different conditions and different seasons most of all. By results of road research on the change of accumulator battery capacity depending on the temperature of the environment, we established that the capacity reduces by 1% with every degree of negative temperature. A comfortable range of temperatures is determined for the use of accumulator battery of car (from 0 to 20 °С) is determined. By results of the research, the indicators of the effectiveness of the use of electric car battery power saving mode are determined – the reduction of the consumption is from 14 to 29 % depending on energy consumers. The significant impact of the pressure values in electric car tires on the energy consumption is established independently from turning on the energy consumers – the increase is from 10% to 40% depending on its speed of movement. Additionally, the determination of the indicators of electric car energy effectiveness for the speed of 140-150 km/h is carried out by which the energy use is 550-670 W h/km and provides the driving distance on the level of 160 km.

The paper presents the results of constructing effective relay protection in the power supply system of a mining and processing plant (MPP). A brief description of the MPP is given, the power supply and substitution circuits used to calculate the short-circuit currents are given. A statistical analysis of failures in the electric network of the MPP has been carried out, which makes it possible to draw conclusions about the nature of failures ranges. Analysis of the registered faults shows that a significant part of them are line-to-earth faults, which in most cases turn into multiphase short circuits, which are interrupted by overcurrent protection. In order to improve the efficiency and reliability of the relay protection, the power supply scheme of the MPP was refined and analyzed. The calculation of the short-circuit currents was made, which made it possible to calculate the settings of the relay protection and give recommendations on the place of its installation and adjustment in order to ensure the normal operation of electricity consumers. To reduce the number of failures to the cable insert on the line leaving the administrative and household complex (AHC), and to increase the reliability of power supply to consumers, it is advisable to divide the capacities of the existing 10 kV line into two parallel ones by laying a second line. It is recommended to install a current cut-off on the line outgoing to the AHC, the feasibility of the installation of which was shown by calculations. This will reduce the chance of failures to the cable gland. Data on the setting currents of overcurrent protection and current cut-off are given on the selectivity card.

There are considered the issues of operational efficiency and reliability of fire vehicles (hereinafter FV) in fires in the Far North and in the Arctic zone. To obtain statistical data on the equipment of fire divisions with PA there were prepared questionnaires and sent to the FPS GPS divisions of EMERCOM of Russia in the regions of the Far North and the Arctic zone. On the basis of the received data, as well as earlier conducted research there was analyzed the age composition of PA and their failures. The necessary recommendations were drawn up for manufacturers to improve the quality of their products.

• The manuscript presents failures observed on voltage transformers (VTs) and CTs that operate at 150 kV and 400 kV, based on statistical data from real operating networks. • Following failure analysis, it is concluded that the percentage of failures for the VTs over the total installed parts on the 150 kV electricity network is higher than that for the CTs. • Even the number of failures for the VTs is larger than the corresponding number for CTs, the statistics show that finally the CTs present considerably less lifetime than the VTs. Electric power infrastructures are considered to be the most critical. The required monitoring of electricity networks is achieved using instrument transformers. The instrument transformer operating conditions must be kept steady, within safe limits. However, this entails comprehension of the several reasons that lead to failure. These reasons can introduce condition assessment monitoring techniques aiming to protect this type of electrical equipment and maybe contribute on their predictive maintenance. This paper describes the probable failures in high voltage instrument transformers with operating voltages of 150 kV and 400 kV, the rate and trend of failures as well as their basic sources. More specifically, this research has been applied for the 150 kV and 400 kV instrument transformers that are installed at the Hellenic Electricity Transmission Network. The results of this work will provide valuable insights about failure cause and operational life of measuring transformers in transmission networks allowing them to improve monitoring and resilience of the networks. [ABSTRACT FROM AUTHOR]

Sewer pipe deterioration is driven by a finite number of root causes and processes. Thus, it should be both feasible and advantageous to have a uniform classification system that can be universally applied in sewer deterioration modeling and asset management. However, a literature review of existing classification systems revealed several problems and inconsistencies, and no widely adopted system. This work proposes a uniform classification system that can be used for different purposes in the fields of gravity pipe deterioration and asset management. This paper focuses on separated sewer systems, but the proposed system can be easily adapted for combined sewer and stormwater systems. The proposed system is based on three top-level categories of failures, defects, and factors with subcategories based on functional considerations. Each category is unambiguously defined and a classification flow diagram is proposed. This work demonstrates how existing parameters can be consistently classified, discusses the interactions between different defects and failures, and illustrates the application of the proposed system to the processes causing overflow failures due to sedimentation. [ABSTRACT FROM AUTHOR]

The electroluminescence technique is presented, which allows qualitative analysis of the condition of the photovoltaic module, applied to the characterization of silicon photovoltaic modules under different conditions. The advantages and the range of applicability of the technique are detailed depending on the environment in which it is done, the technical specifications of the electroluminescence camera and the methodology that was carried out for the characterizations. The results of the implementation of the technique both in laboratory conditions and in a photovoltaic system installed on a roof were presented. Defects were detected such as cells with significant breaks and microcracks; disconnections between cells; corrosion and shunt failures along the fingers caused by stresses in the welding points. Microcracks and breaks are much more frequent than the rest of the faults detected by electroluminescence. [ABSTRACT FROM AUTHOR]

Organic fertilisers could contribute to addressing the issues of declining soil fertility, food security and waste management by recycling human waste for use in sub-Saharan Africa. The variable nutrient content of such products can make targetted application more difficult than in chemical fertilisers. One solution to this could be the use of in-field soil testing and information, particularly with the expansion of mobile technology. This research investigated the role of information and soil testing in 43 farmers using human waste derived fertilisers in Kenya and Ghana. Interviews were conducted to understand the use and sources of information in farming and the perception of soil testing technologies. It was found that mobile based testing was unlikely to be adopted for reasons of low priority, the type of knowledge being shared and trust after failures of different projects. Farmers did not see soil testing as the major issue that they needed to solve. Mobile technology was mostly used for visual and oral communication whereas soil testing often provided information in an unsuitable way. Farmers also had limited trust in new projects as they had previously had project failures that did not help them. In order to achieve sustainable adoption of technology there needs to be improved methods of disseminating and learning from project failures to prevent repeated attempts at inappropriate technology in the future. [ABSTRACT FROM AUTHOR]

The occurrence of inrush currents in power transformers is directly related to the reduction in its lifetime, as well as safe operation of electric power systems. In this article, the linear prediction technique is used to process three-phase current signals and detect the inrush current. The linear predictors of orders 2 and 4 are implemented, and the linear prediction error is designed to detect the phenomenon. The methods performance is evaluated with several different levels of the inrush current simulated in alternative transients program, allowing the creation of a database containing 285 current signals, and the modeled electric system is based on real distribution network. Aiming to evaluate the reliability of the method, Gaussian noise is added to the signals, and a noise sensitivity analysis is performed. The results show the viability of the linear prediction as a tool able to identify the inrush current, which performed successfully in situations with SNR of 55, 60 and 65 dB. [ABSTRACT FROM AUTHOR]

The data related to the failure of bridges that occurred during the period 1977–2017 in India have been collected from various sources, including print and electronic media. The data have been classified under various categories based on their material, cause of failure and others. More than 2130 bridges (excluding culverts and pedestrian bridges) have failed to provide intended service or got collapsed during various phases of construction in recent four decades. Reasons for failure of bridges during their service life as well as during the construction phase have been analysed. The average age of failure of bridges is 34.5 years, which is very low compared to the expected design life. A comparison of the failure cases is made with those from available literature and observed some unique failure patterns of bridges in India. The present study highlights that the collection of data made from open sources can provide information for drawing meaningful conclusions about the service life of bridges. Thus, helps in planning the infrastructural assets management and extending their service life. [ABSTRACT FROM AUTHOR]

Whiskers are small crystalline growths, which can grow from certain metals or alloys. Reaching up to several millimeters long, whiskers have the potential to cause device failures due to short circuits and contamination by debris. Tin (Sn) is one such metal that is particularly prone to whisker development. Until the 2006 RoHS Initiative, lead (Pb) was added to tin in small amounts (up to 2%) to greatly reduce the growth of whiskers. Since then, however, industry has switched to lead-free tin solders and coatings, and the issue of whisker growth on tin has attracted new interest. A reactive-sputtering-deposited nickel oxide sublayer was shown recently to strongly suppress the growth of whiskers from an overlaying tin layer. This paper reports on using nickel oxide films, obtained by a sol–gel dip coating method, as whisker suppressing sublayers. The proposed method is simple, low-cost, and can easily be scaled up for manufacturing purposes. The properties of the sol–gel deposited nickel oxide film were examined using SEM, EDS, and Raman spectroscopy. Samples containing the nickel oxide sublayer were observed through SEM periodically over several months to examine the surfaces for whisker development, and the results show that such layers can be very effective in suppressing whisker growth. [ABSTRACT FROM AUTHOR]

This article assessed the success or otherwise of the Ghana Human Trafficking Act (GHTA), 2005, in curbing human trafficking. On the basis of interviews and secondary information, the assessment was done along the program, process, and politics dimensions. The evidence showed that GHTA achieved fairly its program objectives. However, failures occurred in all the phases of the Act's enactment process. In particular, agenda setting suffered from definitional ambiguity surrounding human trafficking and implementation was mired by resource constraints and financial impropriety. The findings also revealed that an integrated model of human trafficking has greater explanatory power than a single one, but there is inattention to this in extant literature. The article concludes that lessons should be drawn from the specific type as well as the overall program, process, and political failures of the Act. As in this case, an exclusive focus on technical learning to the neglect of potential process and political failures has increased rather than decreased the chances of policy failure. Moreover, the accent on legislative bans to the neglect of other interventions is futile. [ABSTRACT FROM AUTHOR]