Preliminary Study on the Loss Laws of Bearing Capacity of Tunnel Structure

The bearing capacity of the tunnel structure is the essential basis for the structural safety of tunnel engineering. Due to the unpredictability and uncertainty in the tunnel’s surrounding environment, a systematic and unambiguous study on the bearing capacity of the tunnel structure is still lacking. The analysis framework of the bearing capacity of the tunnel structure is discussed and a method describing the bearing capacity loss of the tunnel structure is proposed in this paper. Furthermore, the loss laws of the tunnel structure bearing capacity under various characteristic factors are preliminarily investigated, and suggestions on the research of bearing capacity are put forward. First, the current research contents and methods of the tunnel structure technical status, mechanical characteristics, and bearing performance (directly mentioned) are summarized, the relevant concepts related to tunnel structure bearing capacity are analyzed, and it is clarified that the bearing capacity loss of the tunnel structure can be considered according to the technical status of lining damage preliminary. Then, based on analysis of main causes and influence path of the bearing capacity loss, the influencing factors of the bearing capacity of the tunnel structure are attributed to external load action (i.e., all external causes acting on the tunnel structure in the form of external loads) and material deterioration (i.e., all internal causes leading to the decrease in mechanical properties such as structure strength/stiffness). Several typical factors are listed with specific examples, respectively. Considering the uncertainty of the absolute value of the bearing capacity caused by the surrounding environment of the tunnel, a method describing the bearing capacity of the tunnel structure using relative loss rate and relative value of index is proposed based on the current relevant analysis data of mechanical characteristics of the tunnel structure. Based on the given definitions and rules, the related data on the quantitative analysis of mechanical characteristics of lining structure reported in the literature are statistically analyzed again from the view of loss laws of the bearing capacity. Taking three factors including crack, insufficient lining thickness, and cavity as examples, the corresponding model of the bearing capacity loss is preliminarily analyzed and interpreted. The simplest linear model can be employed to preliminarily describe the relationship between defect indexes and relative loss rate of the bearing capacity, especially pertinent mechanical data collected from numerical analysis. Moreover, the loss laws of the bearing capacity in practical analysis and model tests (especially when the variation range of factors is wide) can be simulated by a logistic growth model. Through the analysis of the typical factor model, the key points of the research on the bearing capacity of the tunnel structure are discussed, and some suggestions are put forward for the follow-up related research.

Piezoelectric Based Touch Sensing for Interactive Displays—A Short Review

Interactive display is an important part of electronic devices. It is widely used in smartphones, laptops, and industrial equipment. To achieve 3-dimensional detection, the piezoelectric touch panel gains great popularity for its advantages of high sensitivity, low cost, and simple structure. In order to help readers understand the basic principles and the current technical status, this article introduces the work principles of the piezoelectric touch panel, widely-used piezoelectric materials and their characteristics, as well as the applications of the piezoelectric touch panel. The challenges and future trends are also discussed.

Magnitude, Causes and Scope for Reducing Food Losses in the Baking and Confectionery Industry—A Multi-Method Approach

Reducing food wastage is one of the challenges in achieving global food security and transforming current food systems. Since human nutrition is closely dependent on cereal production, research was undertaken aimed at understanding the food losses in the baking and confectionery industry (BCI) in Poland, in particular at determining the volume, reasons and ways of reducing losses, identifying possibly all of the reasons for losses in BCI using the Ishikawa 5M + 1E diagram and determining the level of significance and probability of risk of food losses in the analysed sector. Two research methods were used. Quantitative data were collected using the mass balance method from five businesses that served as case studies. Qualitative data were collected through individual in-depth interviews with 17 industry experts. The companies’ average daily losses ranged from 0.8 to 6.4 tons, representing 9.7 to 14.4% of production volume, including 10.4–13.4% of bread losses and 6.8–24.4% of fresh pastry losses. The highest losses were generated by transport departments and these were exclusively retail returns. Following the Ishikawa concept, 31 primary and 94 secondary reasons for food losses were identified. Using the probability of loss risk, a toolkit for loss prevention and mitigation across all departments within businesses (raw materials magazine, production section, final product magazine and final product transport) and a set of horizontal tools were identified, including specialised training for employees and activities in several areas, e.g., technical status and production technology, organisation and planning, logistics and sales and cooperation with retail. This study, conducted in Poland, offers valuable results for developing programmes and strategies to prevent and manage food losses in BCI. Many of the solutions proposed in both toolkits can bring economic benefits without involving additional high costs.

Analysis of Factors Influencing Plant–Microbe Combined Remediation of Soil Contaminated by Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are frequently detected in soil. Their biological toxicity and carcinogenic, teratogenic, and mutagenic effects pose a great threat to the ecological environment and human health. Firstly, the sources, physicochemical properties, and environmental hazards of PAHs are reviewed in this paper, and then their pollution status and different methods for their detection in soil are described in detail. The remediation technologies to treat pollution in the field and farmland are compared, and the technical status and factors influencing phytomicrobial remediation of PAHs in contaminated soil are evaluated in the most comprehensive way. The mechanisms of phytomicrobial remediation of PAHs-contaminated soil under different conditions are innovatively discussed. Additionally, the regulation mechanism of enzymes involved in plant and microbial degradation of PAHs in soils is studied. This is the first study on the regulation mechanism of degradation enzyme in a PAHs review. The aim of this paper is to review the pollution status, remediation technologies, mechanisms, and biodegradation actions of PAHs in soil. This review creatively provides reliable technical support for strengthening soil remediation and environmental management.

System of proactive online servicing of ground-based transport-production machines

Problems of the formation of a system of the proactive online servicing of ground-based transport-production machines, using diagnostic information are discussed. The system is intended for providing reliability and safe operation of ground-based transport-production machines. For the solution of the problem it is necessary the timely detection and prevention of failures, that requires the separation of a special class of intermediate states named «preabnormal». To receive information and statistical data, it is necessary to have systems of online diagnosis, monitoring of technical status, operation modes and location of machines on an object.

The Status under EU Law of Organisms Developed through Novel Genomic Techniques

In a ruling on 25 July 2018, the Court of Justice of the European Union concluded that organisms obtained by means of techniques/methods of mutagenesis constitute GMOs in the sense of Directive 2001/18, and that organisms obtained by means of techniques/methods of directed mutagenesis are not excluded from the scope of the Directive. Following the ruling, there has been much debate about the possible wider implications of the ruling. In October 2019, the Council of the European Union requested the European Commission to submit, in light of the CJEU ruling, a study regarding the status of novel genomic techniques under Union Law. For the purpose of the study, the Commission initiated stakeholder consultations early in 2020. Those consultations focused on the technical status of novel genomic techniques. This article aims to contribute to the discussion on the legal status of organisms developed through novel genomic techniques, by offering some historical background to the negotiations on the European Union (EU) GMO Directives as well as a technical context to some of the terms in the Directive, and by analysing the ruling. The article advances that (i) the conclusion that organisms obtained by means of techniques/methods of mutagenesis constitute GMOs under the Directive means that the resulting organisms must comply with the GMO definition, ie the genetic material of the resulting organisms has been altered in a way that does not occur naturally by mating and/or natural recombination; (ii) the conclusion that organisms obtained by means of techniques/methods of directed mutagenesis were not intended to be excluded from the scope of the Directive is not inconsistent with the negotiation history of the Directive; (iii) whether an organism falls under the description of “obtained by means of techniques/methods of directed mutagenesis” depends on whether the genetic material of the resulting organisms has been altered in a way that does not occur naturally by mating and/or natural recombination. Finally, the article offers an analysis of the EU GMO definition, concluding that for an organism to be a GMO in the sense of the Directive, the technique used, as well as the genetic alterations of the resulting organism, must be considered.

Identification, evaluation and minimization of industrial risks relating to gas pipelines

The security of the functioning systems represents, through the four specific components (security, availability, reliability and maintenance), a basic component of the processing requirement. Monitoring of all specific intrinsic and operating parameters of oil and gas pipelines can be technically detected and diagnosed by: –existing defects; –rapid and effective intervention to eliminate the damage, if they occurred. To establish the maintenance programs that can ensure the proper functioning of the gas pipelines, it is necessary to establish their technical status. The research done helps reduce the risk of gas pipeline damage.

Step-drawdown tests in exploitation wells for thermal and mineral water – Case study from Slovenia

A comparative analysis of step-drawdown tests was performed in order to estimate the well performance in Slovenian thermal and mineral water wells. Tests were performed in 30 wells, each having its own maximum production rate determined in the concession decrees. The main focus of well performance analysis, using graphical analysis of the Jacob approximate equation, was to estimate the adequacy of the wells production rate as well as to identify possible changes in the technical status of the wells over years. 5 of total 30 wells were not included in the analysis due to technical issues during test performance. Well performance analysis includes the calculation of nonlinear well losses related to turbulent flow and linear head loss (aquifer and well) assumed to be related to laminar flow. Results indicate that the ratios between nonlinear well losses and linear head (well and aquifer) losses, in this paper referred as laminar losses, are from 6.9 % to 97.4 %. Laminar losses parameter suggests, all investigated wells were classified with either good (11 wells), medium (7 wells) or poor (7 wells) performance. The addressed analysis represents a very important basis for further thermal and mineral water extraction, e.g. optimizing the maximum allowed production rate as granted in concession decrees and diagnose potential changes in the technical status of each well

EVALUATION OF MG-25 FUSE QUALITY AT LIFE CYCLE AND IDENTIFICATION OF OCCURRING FAULTS

The paper presents an analysis of faults of MG-25 fuse which affect the efficiency of this article in the life cycle and were detected at testing its technical status. The analysis was made on the grounds of test results [1] received for production lots of MG-25 fuses from years 1970-2000. The quantitative contribution of particular faults affecting the quality of this article was illustrated by Pareto-Lorenz method.