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The aim of this study is to investigate the problem of pipe cracking based on T-stress analysis and the influence of other parameters, using a numerical computation performed by extended isogeometric analysis (X-IGA). This article examines the T-stress, which defines the second term of the Williams’ series expansion. T-stress provides effective elastic modeling at the crack tip. Using the extended iso-geometric analysis (X-IGA), we determined the distribution of T-stress at the crack tip in a pipe under internal pressure as a function of internal pressure, crack size, and Poisson’s ratio. To validate the promising findings, the results are expanded with a comparison to the extended finite element (X-FEM) method and existing research in this field, and we obtained an error between 0.2% and 4.6%. This work demonstrated the significance of T-stress in fracture description, the effect of Poisson’s ratio and size on T-stress, and that X-IGA provided accurate numerical results by precisely describing the geometry of the crack and enriching it.

Keywords: History; Infrastructure; Federal Legislation; Federal Funding; Lakes; Rivers; Estuaries; Wetlands; Habitats; Wildlife; Pipes; Lead; Service Lines; Emerging Contaminants EN History Infrastructure Federal Legislation Federal Funding Lakes Rivers Estuaries Wetlands Habitats Wildlife Pipes Lead Service Lines Emerging Contaminants 6 8 3 04/07/22 20220401 NES 220401 The bipartisan Infrastructure Investment and Jobs Act (P.L. 117-58) provides a historic opportunity to deliver on the promise of clean water, now and for future generations. Congress established the SRFs as subsidized loan programs that would be capitalized with a federal grant, plus state funding equivalent to 20% of federal funding. [Extracted from the article]

We develop a complex technology of fabrication of oil-and-gas pipes with elevated corrosion resistance, including the procedure of controlled forge-rolling of pipe blanks of 06X1-Y steel with regulated contents of chemical elements and the procedure of heat treatment, namely, hardening with double short-term high tempering at temperatures maximally close to the temperature of the α → γ phase transformation of steel. It is shown that pipes made of this steel have a fine-grained ferrite-pearlitic structure with high (up to 23%) contents of special α –α and α –γ low-energy boundaries and elevated corrosion resistance observed in the course of testing of the specimens in chloride and model chloride-acetate solutions. Moreover, these pipes are less susceptible to hydrogenation under the conditions of cathode polarization in 1 N H2SO4 + 1.5 g/liter CS(NH2)2 and exhibit higher resistances both to sulfide stress corrosion cracking (SSCC) and to hydrogen-induced cracking than the pipes made of 20 steel. It is shown that the procedure of heat treatment performed according to the developed technology increases the SSCC resistance (σgr ≥ 0.85 σ0.2) and improves the mechanical properties of the pipes up to the strength grade X56 according to the standard of the American Petroleum Institute API 5L. [ABSTRACT FROM AUTHOR]

Key Takeaways: Water utilities typically replace aggregated clusters of pipelines rather than individual pipes to minimize repeated disruption and mobilization cost. Risk assessments that report high‐risk pipes at the resolution of individual segments fall short of the clustering approach. A postprocessing method improves risk assessment efficacy by scaling risk calculations from individual pipe segments to a more meaningful and actionable cluster resolution. [ABSTRACT FROM AUTHOR]

Performance-based earthquake engineering requires the harmonization of performances between structural and nonstructural elements. This paper discusses the performance-based seismic design of nonstructural elements through a direct displacement-based methodology applicable to nonstructural elements attached to a single location in the supporting structure and for which damage is the result of excessive displacements. The fundamentals of direct displacement-based seismic design are presented along with a description of the modifications required for its application to nonstructural elements. As an example, the direct displacement-based seismic design of a suspended piping restraint installation is presented. The design approach is appraised by nonlinear dynamic time-history analyses. [ABSTRACT FROM AUTHOR]

Underground accidental explosions are caused by the detonation of explosive materials (solid, liquid or gas) stored below the ground surface. In this study, effects on underground pipes due to varying degrees of underground accidental explosions between the ground surface and buried concrete and steel pipes were studied using ABAQUS, a finite element numerical code. Concrete and steel pipes buried in loose sand and dense sand at various depths below the ground surface were modelled. The material properties as revealed by several researchers were used. Pipe and soil materials were limited to linear, elastic, homogeneous and isotropic. The observed parameters are displacement, pressure, mises, stress and strain at the crown, invert and spring-line of buried pipes. The results showed that irrespective of the ground media, at a given loading wave velocity, displacement remains relatively constant as the embedment ratio increases. Even though there is variation in the results due to dilations and compressions caused by the transient stress pulse of compression wave, some of the observed parameters reduce as the depth of burial of pipes increased. [ABSTRACT FROM AUTHOR]

Because of the special forging material and complex pipe structure of the main pipe of the AP1000 nuclear power plant, a single general equipment can not meet the requirements of machining the inner hole of the bending section. At present, most of them adopt the method of approaching theoretical dimension by manual grinding, which makes the labor intensity of workers large, the work cycle is long, and it is difficult to ensure the machining accuracy of the workpiece. In view of the practical difficulties in processing the elbow inner hole of nuclear power main pipeline, the copying processing equipment is designed. The fixed circular arc guide rail is used in the equipment. The arc curvature of the guide rail is the same as that of the workpiece. The boring cutter head moves axially along the fixed circular arc curvature guide rail for copying boring. After testing, it fully meets the requirements of the shape, position and size accuracy of the inner hole in the bending section of the nuclear power main pipeline. The method is efficient, accurate and innovative, and provides reference for similar product processing schemes.

By exploring the effects of energy and velocity under different inlet speeds and abrasive concentrations, different inlet boundary conditions were selected for numerical analysis, and the intrinsic properties of the solid–liquid two-phase abrasive flow research and development calibre pipes were explored. The influence of law and process characteristics of solid–liquid two-phase abrasive flow is discussed. The fourth-order variable diameter pipe is taken as the research object. It is concluded that the inlet velocity is increased, the total energy and kinetic energy of the abrasive grains are also increased, and the total energy and kinetic energy are increased. The more intensely the abrasive grains collide with the workpiece wall, the more favourable is the effect of the abrasive flow on the wall surface finishing, and the increase of the abrasive concentration. The number of collisions of the disordered abrasive grains on the wall surface is increased, which is more conducive to the wall surface. The finishing process provides theoretical reference and technical support for the engineering application of solid–liquid two-phase abrasive flow.

To study the quality control technology and process specifications of solid–liquid two-phase abrasive flow research and development, the fourth-order variable diameter pipe is taken as the research object, and then the quality control method of abrasive flow polishing variable diameter pipe is established. Through the analysis of the abrasive flow of the fourth-order variable-diameter pipe, it is known that the surface texture of the variable-diameter pipe becomes smoother and denser after the grinding flow, and the surface roughness Ra of the variable-diameter pipe is reduced from the original 1.469 μm to after polishing 0.295 μm, the surface roughness is improved, and the ideal polishing quality is obtained. Under the experimental conditions, the optimal process parameters of solid–liquid two-phase abrasive flow were obtained, and the regression model of surface roughness and process parameters was established, which provided technology for engineering application of solid–liquid two-phase abrasive flow.

Pipes are widely used in many industrial and mechanical applications and devices. Although there are many different constructions according to the specific application and device, these can show helical pattern, such as spiral pipes, wire-reinforced pipes/shells, spring-suspension, and so on. Theoretical modelling of wave propagation provides a prediction about the dynamic behavior, and it is fundamental in the design process of these structures/devices and in structural health monitoring techniques. However, standard approaches have limitations in terms of difficulties in modelling and impossible computational cost at higher frequencies. In this study, the wave characteristics in waveguides with helical patterns are obtained using a Wave Finite Element (WFE) method. The method is described for a 1D and 2D waveguide with helical properties and it is illustrated by numerical examples. These include the optimization of stop-bands for a fluid-filled pipe with concentrated masses and a cylindrical structure with helical orthotropy.

On the basis of the solution of the equation of the movement (in conception of «vortex backfill”) offered earlier, the generalized formula for a profile of speed of a turbulent and laminar current in pipes is received. The formula has binomial power shape. The received solution allows to consider speed of a turbulent kernel of a stream, or, more precisely, averaged on time value of axial component of this speed, as the sum of three items - carrying, parabolic and power but not parabolic. It is shown that the profile of turbulent speed of the basic part of a stream is described by the parabolic component. Transformation of the equation of movement in which solutions both laminar, and turbulent profiles of speeds (in the basic part of a stream) are direct lines (or very close to them) is offered. Some features of turbulent flow, similar to currents in a granular layer are noted.

Urban scholars have long proposed moving away from a conceptualisation of infrastructure as given and fixed material artefacts to replace it with one that makes it the very object of theorisation and explanation. Yet, very few studies have seriously investigated the role of infrastructure in co-shaping and mediating inequities. We use this paper to propose a way to engage with the technical intricacies of designing, operating and maintaining a water supply network, using these as an entry-point for describing, mapping and explaining differences and inequities in accessing water. The paper first proposes a methodological approach to systematically characterise and investigate material water flows in the water supply network. We then apply this approach to the case of water supply in Lilongwe, Malawi. Here, strategies for dealing with challenges of water shortage in the city have often entailed the construction of large water infrastructures to produce extra water. We show that the network’s material properties direct and divert most of the extra water to elite neighbourhoods rather than to those low-income areas where shortages are most acute. Our analysis shows how social and technical processes mutually constitute each other in the production and rationalisation of this highly uneven waterscape. We conclude that further theorisations of infrastructure as providing part of the explanation for how urban inequities are produced need to be anchored in the systematic and detailed empirical study of the network-in-use. Mapping the (changing) carrying capacities of pipes, storage capacities of service reservoirs and the strategic locations of new pipe extensions – to name a few important network descriptors – provides tangible entry-points for revealing and tracing how materials not only embody but also change social relations of power, thereby helping explain how inequities in access to water come about and endure.

In this paper, a comparative theoretical analysis of the efficiency and applicability of some known types of thermal insulation in relation to the regimes typical for the MCU recovery systems is carried out. The study is carried out numerically by modeling heat transfer processes in the «coolant-wall-hot gas-snack-insulationenvironment» system, i.e. in a simplified version of the recuperative heat exchanger. As the external insulation of the heat exchanger, four most common types of insulation are used: foam insulation materials, fibrous, vacuum and active water insulation

The earliest record that testifies to the South Slavic music is the one left by the Byzantine chronicler Theophylact Simocatta in his History. It is said that in 592, the emperor Maurice captured three Slavic men near Enaton, who did not have any weapons on them, but had only musical instruments, most probably lyres. Some written sources also mention the horns. Implementing the knowledge obtained through etymological analyses and the extant ethnological practice, as well as archaeological artefacts, it may be said that the Slavs of the said period used jingle bells, flutes and bagpipes. The music, both instrumental and vocal, was common to religious as well as entertainment purposes.

The principle of centrifugal force produced by flowing fluid through the semicircular section of a pipe line is not sufficient to explain the characteristic of the centrifugal force type flow transducer developed from this principle. In this study, a modified form of this flow transducer is developed using a modified force sensing technique. This modified force principle explains the characteristic of the flow transducer to a very good extent. The modified force produced in the modified transducer system is composed of four components namely, centrifugal force, momentum force, damping force and restoring force. These forces produce the identical downward and upward movements of the lever ends of a common balance which is initially made horizontal at zero flow by using similar sensing U‐tube and dummy U‐tube. These movements are sensed by two identical inductive sensors. The static characteristic equation of the prototype unit of the transducer using the modified force sensing technique is derived mathematically in the study. The equation coefficients are calculated from the design parameters and are found to be matched with the same obtained from the average characteristic of repeated experiments performed under the same laboratory environment. Thus the proposed modified model appears to be established. [ABSTRACT FROM AUTHOR]

Laminar forced convection in viscous, non-Newtonian polymeric liquids that exhibit pseudoplastic or shear-thinning behavior is characterized. The fluid rheology is characterized by a new asymptotic power-law (APL) model, which appropriately represents extensive data for apparent viscosity variation with shear rate--from the low-shear constant-viscosity plateau to shear thinning at high shear rates. This is contrasted with the traditional Ostwald-de-Waele or power-law (PL) model that invariably over-extends the pseudoplasticity in the very low shear-rate region. The latter's limitations are demonstrated by computationally obtaining frictional loss and convective heat transfer results for fully developed laminar flows in a circular pipe maintained at uniform heat flux. The Fanning friction factor and Nusselt number, as would be anticipated from the rheology map of pseudoplastic fluids, are functions of flow rate with the APL model unlike the Newtonian-like constant value obtained with the PL model. Comparisons of the two sets of results highlight the extent of errors inherent in the PL rheology model, which range from 23% to 68% for frictional loss and 3.8% to 13.7% for heat transfer. The new APL rheology model is thus shown to be the more precise characterization of viscous shear-thinning fluids for their thermal processing applications with convective heat transfer. [ABSTRACT FROM AUTHOR]

The excess hydraulic pressure in water supply network pipes is one of the major problems in design and implementation stages of these projects. To reduce the excess pressure and maintain network safety, a variety of pressure reducing valves are used, which waste all the excess pressure. However, having used the appropriate water microturbines, while reducing the pressure loss to an optimum value, the system could recover the wasted energy. In this study, numerical simulation and experimental investigation of microturbine in a water supply system have been performed to evaluate the electrical power generation capacity of an over‐pressured network. The numerical simulation of the microturbine was conducted using Ansys‐Fluent software. The microturbine has been experimentally investigated with different inlet flow rates, the effect of different post‐microturbine heads and also the effect of different opening angles of guide plate on its performance, three different scenarios were defined. Based on numerical simulation and laboratory results, the best performance of the microturbine was obtained when the inlet flow rate was 0.01184 m3 /s and also opening angle 20° for the guide plate, in which the microturbine output was equal to 59.01 W. The generated power by the microturbine can meet the electrical needs of sensors and other network monitoring equipment. [ABSTRACT FROM AUTHOR]

Probabilistic design factors for pipes used for hydrogen transport are proposed for 3 locations: urban, peri-urban and rural areas. The used method involves a risk equation defined as the product of probability of leakage after failure, probability to have a gas flow greater than a prescribed value, probability of ignition, probability of lethal effects greater than a threshold value and probability of the presence of a person corrected by an environment factor and a risk reduction coefficient. The results obtained are less conservative than the deterministic values provided by ASME code. • Probabilistic design factors for pipes have been established. • The used method involves a risk equation. • This approach is based on assumption of a risk 10−5 probability. • The results obtained are less conservative than values provided by ASME code. [ABSTRACT FROM AUTHOR]

In the case of the glass tube for pharmaceutical applications, high‐quality defect detection is made via inspection systems based on image processing. Such processing must be fast enough to guarantee real‐time inspection and to meet the increasing rate and quality required by the market. Defect detection is complex due to specific problems of the production process: vibration, rotation and irregularity of the tube. All these aspects prevent the efficient use of known techniques. The authors present an algorithm that decreases the processing time of the defect detection phase. The algorithm is based on a moving average filter working at row level, that allows to minimize the effects of rotation, vibration, and irregularity of the tube. Luminosity variations due to the tube curvature are cut by the filter and a threshold algorithm can be applied. They made the evaluation considering different solutions taken from literature. The algorithm outperforms, in processing time, all these solutions with increased accuracy. Experimental measures show that the algorithm achieves a throughput gain of 2.6 times with respect to Canny. They develop also a methodology to get the best values for the algorithm parameters directly at the factory, during the change of production batches. [ABSTRACT FROM AUTHOR]

Experimental investigations of the flows inside helically coiled pipe are difficult and may also be expensive, particularly for small diameters. Computational fluid dynamics (CFD) packages, which can easily construct the geometry and change the dimensions with 100% of accuracy, provide an alternative solution for the experimental difficulties and uncertainties. Therefore, a CFD study was conducted to analyze the flow structure and the effect of varying the coil pitch on the coil friction factor, through utilizing different models' configurations. Two coils were tested, all of them sharing the same pipe and coil diameter: 0.005 m and 0.04 m, respectively. Pitch variations began with 0.01 and 0.05 m for the first and second model, respectively. In this study, the velocity was analyzed, and the effects of this reduction on coil friction factor were also examined using laminar flow. The results were validated by Ito's equation for the laminar flow. [ABSTRACT FROM AUTHOR]

This paper provides a novel classification scheme for magma-induced subsurface vent complexes based on morphometric data and stacking patterns. The study area is the Naglfar Dome in the Vøring Basin where the interaction between magmatic intrusions and vent complexes is well known. Seismic interpretation, characterization and morphometric analyses of 35 vent complexes observed within the Palaeocene-Eocene strata were done from a high-quality, three-dimensional seismic reflection data. The vent complexes have dome-shaped, eye-shaped, fault-controlled and reactivated upper termini, and are linked to their root zones by columnar, downward-tapered and fault-related fluid conduits or pipes. Statistical analyses and cross plots of L-A and Dmax-Hmax allowed the discrimination of vents and pipes into their genetic types. A new classification scheme based on the morphometric sub-division and structures of subsurface vent complexes is introduced to include S-P-V, S-P-F, V-P-V and V-P-F types. These combinations freshly demonstrate the importance of morphometric data at deciphering the nature, timing, classification and activity of subsurface fluid vent complexes. [ABSTRACT FROM AUTHOR]

The work results on the production reconstruction in order to increase pipe competitiveness conducted in 2002–2019 by metallurgical companies were considered. An analysis of the work of pipe enterprises by pipe types in 2015–2020 was given. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) gas pipes are introduced in Algeria in 1978 to substitute the old pipelines made by copper, steel and cast iron. These later were used for the distribution of natural gas with medium working pressure of four bars. In this study, the polyethylene pipes were extracted from the Algerian distribution gas network in order to study their characteristics after more than 30 years of use. Two different pipe diameters (Ø63 and Ø125) with different ages of use were characterized according to the specifications on the EN1555-2 standard. The dimensional, physical and mechanical tests were performed with the same parameters as a newly produced pipe. The results showed that most of the characteristics are still fitting the EN 1555-2 specifications except for the density and the oxidative induction time. These two later will be considered as two basic parameters for the future studies of the polyethylene aging. [ABSTRACT FROM AUTHOR]

The authors propose a new non-destructive inspection method for underground fiberglass-reinforced plastic mortar (FRPM) pipelines. Their method utilises time-domain responses of microwave guided-modes propagating along an FRPM pipe-wall. Through the time-domain analyses, they found that a microwave guided-mode signal propagating along a pipe-wall is spread out to various waves corresponding to straight and circumferential waves along the pipe-wall and that the position of an unwanted foreign object on the wall can be detected by examining the path of the wave interrupted by the foreign object. Additionally, they also derived a propagation equation that enables them to calculate a time-domain response of the spread microwave guided-mode signals propagating along the pipe-wall. This method can be applied to pipelines consisting of various types of materials. [ABSTRACT FROM AUTHOR]

By exploring the effects of energy and velocity under different inlet speeds and abrasive concentrations, different inlet boundary conditions were selected for numerical analysis, and the intrinsic properties of the solid–liquid two-phase abrasive flow research and development calibre pipes were explored. The influence of law and process characteristics of solid–liquid two-phase abrasive flow is discussed. The fourth-order variable diameter pipe is taken as the research object. It is concluded that the inlet velocity is increased, the total energy and kinetic energy of the abrasive grains are also increased, and the total energy and kinetic energy are increased. The more intensely the abrasive grains collide with the workpiece wall, the more favourable is the effect of the abrasive flow on the wall surface finishing, and the increase of the abrasive concentration. The number of collisions of the disordered abrasive grains on the wall surface is increased, which is more conducive to the wall surface. The finishing process provides theoretical reference and technical support for the engineering application of solid–liquid two-phase abrasive flow. [ABSTRACT FROM AUTHOR]

To study the quality control technology and process specifications of solid–liquid two-phase abrasive flow research and development, the fourth-order variable diameter pipe is taken as the research object, and then the quality control method of abrasive flow polishing variable diameter pipe is established. Through the analysis of the abrasive flow of the fourth-order variable-diameter pipe, it is known that the surface texture of the variable-diameter pipe becomes smoother and denser after the grinding flow, and the surface roughness Ra of the variable-diameter pipe is reduced from the original 1.469 μm to after polishing 0.295 μm, the surface roughness is improved, and the ideal polishing quality is obtained. Under the experimental conditions, the optimal process parameters of solid–liquid two-phase abrasive flow were obtained, and the regression model of surface roughness and process parameters was established, which provided technology for engineering application of solid–liquid two-phase abrasive flow. [ABSTRACT FROM AUTHOR]

The purpose of this research was to determine an alternative formula for calculating the Darcy coefficient in turbulent flow in pipes. The proposed alternate formula is an explicit formula that should be used to replace the Colebrook-White formula for calculating the Darcy coefficient in turbulent flow in pipes since it has higher precision than the explicit formulas that are currently in use. In this investigation, the alternate formula was compared with two explicit formulas commonly used in pipe design, the Swamee-Jain and Pavlov formulas. To determining which formula is better, all of them were compared with the Colebrook-White formula. For this, the average percentage and maximum percentage errors of the Darcy coefficient values calculated with each of the explicit formulas were determined, with the values obtained with the Colebrook - White formula. It was determined that the maximum errors in the calculation of the Darcy coefficient concerning the Colebrook-White formula were: 3,104% for the Swamee-Jain formula, 7,973% for the Pavlov formula and 2,740% for the alternate formula. [ABSTRACT FROM AUTHOR]

This study reports a newly designed induction heating system for efficient, fast, and safe flow-through heating. The system has a very simple architecture, which is composed of a transmitting coil, an isolating plastic pipe, and an embedded metal shell. Wireless energy transfer from the external coil to the internal metal shell through the pipe is essential for decreasing losses. Also, a large contact surface between a fluid and the immersed shell enables rapid heat transfer. The proposed heating system was systematically investigated for different shell geometries and the results were compared with a commercially available conductive flow-through heating device. As a proof-of-concept demonstration, a prototype of the designed induction heating system was manufactured and the heating measurements were conducted with water. Power transfer efficiency of the prototyped induction heating system was measured to be 97%. The comparative study indicates that such high-efficiency induction flow-through heating system offers a great potential for replacing the conventional conductive heating device used in household applications in which the rapid and compact heating is desired. [ABSTRACT FROM AUTHOR]

Real‐time monitoring tools were used to gauge the condition of a prestressed concrete cylinder pipe to help a Colorado utility target high‐risk pipe areas and predict future renewal needs [ABSTRACT FROM AUTHOR]

Subsurface pipes related to fluid flow are observed in seismic reflection data as vertical to sub-vertical features of low-amplitude reflections, linking chaotic reflections at the base (root zones) of volcanic constructs to their summits which can comprise craters, mounds or eye-shaped vents. To date, uncertainties remain regarding the linear correlation and scaling relationship between pipes and their overlying vent structures. Using 3D seismic reflection data from a magma-rich basin, the Vigrid Syncline in the Vøring Basin (offshore Norway), this study provides a seismic, morphometric and statistical description of forty (40) pipes and their associated structures. These pipes include conical, bifurcated, fault-controlled and columnar types, which are a consequence of the intrusion of two mappable magmatic sills of Early Eocene age. The heights (av. 1098 m), widths (av. 1740 m) and slenderness ratios (i.e. the heights/widths (Ω)) of the pipes (av. 0.6) show low to moderate correlation coefficients with vent parameters such as height (av. 258 m), area (av. 2.3 km2) and ellipticity (av. 1.5). The morpho-statistical analyses provided here show that 'pipe' formation mechanisms are mutually exclusive and that vent geometries are not particularly systematic in nature. [ABSTRACT FROM AUTHOR]

This paper presents a new method of simulating the dynamic flow and pressure of laminar liquid flow through pipes of arbitrarily changing cross section. This method uses a segmented model based on the previously presented tapered transmission line model (TLM). This new method is computationally efficient and has comparable accuracy to previous methods such as the method of characteristics (MOC), but allow for more flexibility in solution time-step (such as accommodating variable time-step solvers), which is required if the rest of the system model has stiff equations. For the sample geometry presented, the new model calculates the dynamic response an order of magnitude faster than the previous method of characteristics solution, with minimal loss of accuracy. [ABSTRACT FROM AUTHOR]

Key Takeaways: Utilities replace water mains by responding to failures or proactively choosing pipes likely to fail. Machine learning can find fragile pipes more accurately than using age or historical breaks as indicators. More accurate and often less expensive than other condition assessments, machine learning uses hundreds of variables to find patterns most people can't see. Timely selection of the right pipes to inspect, repair, or replace can reduce breaks and optimize the pipes' remaining useful life. [ABSTRACT FROM AUTHOR]

In this paper we provide new insights into the motives underlying insider participation in private investments in public equity (PIPEs) by considering the association among insider participation, pricing, and contractual terms. PIPEs are a financing choice that have become popular over the last decade and frequently involve insider participation. We find that board seats and weak pre-PIPE performance are important determinants of insider participation. We also find evidence in support of the certification motive for insider participation. In particular, we show that insider participation is associated with lower PIPE discounts and improved future firm operating performance. Announcement wealth effects are significantly higher when insiders participate than when they are absent both for single and repeated PIPE transactions. We extend the prior literature by documenting that the insider certification effect also exists for repeated PIPE transactions and that the granting of control mechanisms, such as board seats, is an important component of contractual arrangements in insider participation, potentially to achieve incentive alignment by mitigating moral hazard considerations. [ABSTRACT FROM AUTHOR]

Underground pipelines are an essential part of the transportation infrastructure. The structural deterioration of pipelines crossing railways and their subsequent failures can entail critical consequences for society and industry, resulting in direct and indirect costs for all the stakeholders involved. Therefore, continuous and accurate condition assessment is critical for the effective management and maintenance of pipeline networks within the transportation infrastructure. The aim of this study has been to identify failure modes and consequences related to pipelines crossing railway corridors. Expert opinions have been collected through interviews and two sets of questionnaires have been distributed to the 291 municipalities in Sweden, with 137 responses in total. The failure analysis has revealed that pipe deformation has the highest impact, followed by pipe rupture at locations where pipelines cross railway infrastructure. For underground pipelines under railway infrastructure, ageing and the external load were awarded a higher ranking than other potential causes of pipeline failure. [ABSTRACT FROM AUTHOR]

The aim of this study is to identify the appropriate parameters for predicting the potable water pipes deterioration. The study evaluated the strength of some variables related to pipe breaks probability of failure based mainly on logistic regression model. The independent variables included in the study are static variables such as pipe diameter, pipe length and pipe material in addition to some dynamic (time-based) variables such as pipe age, water pressure and water velocity. The pipe break history (number of pipe breaks) for each pipe segment is used as dependent variable to be predicted in the statistical model. The resulted prediction equation is then used to calculate the failure probability for each pipe in the potable water network. Finally, prioritization of pipes is performed and the annual renewal plan is developed for the city of Jubail Industrial City in KSA based on the model results. [ABSTRACT FROM AUTHOR]

This paper analyzes the quality of welded joints of high temperature resistant steel pipe at electron beam welding, knowing that the mechanical properties of these types of steels are influenced by the interaction of different processes specific to physical and mechanical metallurgy. Analyzing the values of the local hardening estimator ΔHV10 calculated between the characteristic areas of welded joints, it is observed that it has a decreasing tendency at thermally de-stressed joints, in all areas of the welded joints, especially in the welded seam. [ABSTRACT FROM AUTHOR]

In‐line inspection (ILI) robot has been considered as an inevitable requirement to perform non‐destructive testing methods efficiently and economically. The detection of flaws that could lead to leakages in buried concrete pipes has been an area of great concern to the oil and gas industry and water resource‐based industry. The major problem is the difficulty in modelling the detection of cracks as a result of its irregularity and randomness that cannot be easily detected. This work covers the study of defect detection of non‐destructive testing methods using fusion inspect sensors, light detection and ranging, and optic sensors. Studies on ILI robots are also reviewed to construct an efficient gauge. Nevertheless, the study on current support vector machine (SVM) technique is centred as the main classification engine for the combined sensory data. The prototype robot has been designed and successfully operated in a lab‐scale environment. Intuitively, the obtained data described the status of inspected pipe clearly. Sensors from the proposed list also well integrated as attaching to the robot. The experiments with SVM techniques to evaluate the feasibility of defects detection also achieved remarkable results. [ABSTRACT FROM AUTHOR]

The costs for piping comparisons should include both the costs of the materials as well as construction. The construction costs depend on the trench depth, type of the soil, presence of rock, type of bedding material or location (urban and rural areas). The average costs of pipes were analysed in the article depending on material type, diameter and trench depth. The data relating to the pipe prices were collected on the basis of BISTYP cost base. Moreover, a preliminary analysis of sewage and water supply system cost was made on the basis of technical documentations published in Public Information Bulletins of communes. Recently, there has been a significant increase of interest in plastic pipes. Due to the low price and availability, these materials are most common used during piping both rural and urban areas. [ABSTRACT FROM AUTHOR]