States Of Deterioration Research Articles

Journal Vol – 19 No -1, January 2024 Journal > Journal > Journal Vol – 19 No -1, January 2024 RELIABILITY OPTIMIZATION OF A DEGRADED SYSTEM UNDER PREVENTIVE MAINTENANCE USING GENETIC ALGORITHM Authors: Shakuntla Singla, Diksha Mangla, Poonam Panwar, S Z Taj DOI NO: https://doi.org/10.26782/jmcms.2024.01.00001 admin January 20, 2024 Abstract: The reliability parameters of a Mathematical model are analyzed for

The present paper deals with the lacunary interpolation problem called the mixed values problem or (0, 3; 0, 2) problem for which known data points are function values at all the points, third derivatives at even knots, and second derivatives at odd knots of the unit interval I = [0,1]. For this problem, we obtained an interpolating function. The paper is divided into two parts, where we have shown that the spline function exists and is convergent.

RELIABILITY OPTIMIZATION OF A DEGRADED SYSTEM UNDER PREVENTIVE MAINTENANCE USING GENETIC ALGORITHM

The reliability parameters of a Mathematical model are analyzed for a system with three identical units and a standby. In this study, the primary unit is considered more important due to its high cost and working in two types of degraded conditions before a complete malfunction. Under the concept of preventive maintenance, the states of deterioration are reversed. The working of the system under two different efficiencies is discussed. The reliability of the Mathematical model, depending on the availability and working time, has been optimized using the Mathematical tool “Genetic Algorithm”. The optimum values of all parameters based on the exponential distribution are considered to optimize the reliability, and thus provide maximum benefits to the industry. Sensitivity analysis of the availability and the working time is carried out to understand the effects of changing parameters. Graphical and tabular analyses are presented to discuss the results and to draw conclusions about the system’s behavior.

Concrete reinforcement using composite fiberglass-based materials

Numerous existing structures, both old and new, have serious load-bearing capacity issues, which, in some cases, could endanger the safety of their users. In fact, we can say that these structures are nearing (or have already reached) the end of their useful lives, necessitating the need to find technical and financial solutions to renovate them as efficiently as possible. Many reinforced concrete bridges experience advanced states of deterioration as a result of extended exposure to hostile environments or even continuously rising use loads. Additionally, since the time of their construction, the technical standards used for the design and dimensioning of the old structures have had to be updated. As a result, some structural components that are still in use do not adhere to the standards for response to loads. In fact, it is frequently less expensive to reinforce the structural components of buildings than to perform a full reconstruction, especially now that, thanks to technological advancements, a variety of reinforcement techniques are still available and their costs are decreasing. One such technique involves externally reinforcing reinforced concrete elements with composite materials because of their superior strength-to-weight ratio and resistance to abrasion. Additionally, these composite materials can be utilized for column containment as well as shear and bending reinforcement for beams. This study aims to evaluate the impact of glass fibers on the general behavior of concrete, in particular on its resistance, deformations, and ductility, using FRP: Fiber-reinforced plastics are materials generally formed of two main and distinct elements: the fiber, "made from glass," and the matrix, "an epoxy resin that allows the transfer of loads between the fibers. The results of the specimens' cyclic loading tests attest to the significance of the contribution that concrete specimen confinement with FRP can make in terms of deformation and resistance to compression after the completion of static loading tests. However, these tests on the specimens' ability to withstand loading and unloading cycles reveal a very significant improvement.

Performance evaluation of deteriorated and rehabilitated corrugated metal pipe culverts using multiphysics simulation

Owing to their high strength to cost ratio, corrugated metal pipes (CMPs) are well accepted among professionals for accommodating water runoff under roadways and railroads. Installed CMPs reach various states of deterioration over their service life resulting in diminishing strength. This can result in a sudden collapse of the CMP and thus, poses a risk of traffic disruption and a threat to public safety. To restore the capacities of aging CMPs, appropriate rehabilitation methods are required after relevant condition assessment techniques are utilized for projecting service life. This paper presents a multiphysics simulation study to assess the structural performance of new, deteriorated, and rehabilitated CMPs in buried conditions. The validity of the developed model was obtained by comparing simulation results with previously conducted full-scale tests. This study investigated performance improvement by two trenchless rehabilitation techniques – cured-in-place-pipe (CIPP) and sliplining with high-density polyethylene (HDPE) liner. The deflections obtained from the simulations under various static surface loads are also compared with values computed using the Modified IOWA equation. The results demonstrate that the deflections obtained by the numerical model offer better agreement with full-scale tested CMP deflections than does the Modified IOWA equation.

Outcomes of second-tier rapid response activations in a tertiary referral hospital: A prospective observational study

A second-tier rapid response team (RRT) is activated for patients who do not respond to first-tier measures. The premise of a tiered response is that first-tier responses by a ward team may identify and correct early states of deterioration or establish goals of care, thereby reducing unnecessary escalation of care to the RRT. Currently, utilisation and outcomes of tiered RRTs remain poorly described. A prospective observational study of adult patients (age ≥18 years) who required RRT activations was conducted from February 2018 to December 2019. There were 951 consecutive RRT activations from 869 patients and 76.0% patients had a National Early Warning Score (NEWS) ≥5 at the time of RRT activation. The majority (79.8%) of patients required RRT interventions that included endotracheal intubation (12.7%), point-of-care ultrasound (17.0%), discussing goals of care (14.7%) and intensive care unit (ICU) admission (24.2%). Approximately 1 in 3 (36.6%) patients died during hospitalisation or within 30 days of RRT activation. In multivariate analysis, age ≥65 years, NEWS ≥7, ICU admission, longer hospitalisation days at RRT activation, Eastern Cooperative Oncology Group performance scores ≥3 (OR [odds ratio] 2.24, 95% CI [confidence interval] 1.45-3.46), metastatic cancer (OR 2.64, 95% CI 1.71-4.08) and haematological cancer (OR 2.78, 95% CI 1.84-4.19) were independently associated with mortality. Critical care interventions and escalation of care are common with second-tier RRTs. This supports the need for dedicated teams with specialised critical care services. Poor functional status, metastatic and haematological cancer are significantly associated with mortality, independent of age, NEWS and ICU admission. These factors should be considered during triage and goals of care discussion.

Identification and analysis of pathological defect appearance in superstructures of reinforced-concrete bridges in Chapare region, Bolivia

The objective of this article is to identify and analyze the main pathological manifestations in bridges in the Chapare - Bolivia region, an area characterized by high humidity and constant rainfall throughout the year. The methodology consisted of the selection of five bridges that showed evident signs of deterioration, in which a visual inspection was carried out and, subsequently, different tests: sclerometer, carbonation depth, penetration of chlorides and core extraction. All the bridges present advanced states of deterioration; highlighting corrosion as the main problem, generating detachment of the concrete and risk of collapse. Although the concrete has a compression strength greater than 30 MPa, the existing carbonation process and the different problems encountered compromises it. It is necessary that the entities in charge provide inspection and maintenance programs according to the environmental and structural characteristics of each bridge.

The use of Atlantic hagfish (Myxine glutinosa) as a bioindicator species for studies on effects of dumped chemical warfare agents in the Skagerrak. 2. Biochemical biomarkers

The sea bottom of the Skagerrak Strait (North Sea) contains munitions loaded with chemical warfare agents (CWA), mostly stored in shipwrecks scuttled intentionally after the end of the World War II. The munition shells inside the wrecks are in different states of deterioration and corrosion and their environmental risk potential is unknown. The Atlantic hagfish (Myxine glutinosa), a sediment-dwelling chordate, was used as a model organism to study the potential impact of dumped CWA on the local ecosystem by using biochemical biomarkers. The hagfish were collected in 2017 and 2018 at three sampling sites: in the immediate vicinity of a wreck with CWA in the Skagerrak, a few kilometres from the wreck, and a reference site 21 km from the wreck, considered to be free of CWA. Significant differences were observed between the wreck site and the reference sites in the activities of glutathione reductase, superoxide dismutase and glutathione S-transferase, while the activity levels of catalase and acetylcholinesterase were identical at all sites. The recorded differences demonstrated negative biological effects in the hagfish sampled close to the dumped chemical munitions. Due to the limited knowledge of hagfish biology and of the extent of CWA contamination in Skagerrak, the results presented here warrant more research to further elucidate the potential environmental risks of the scuttled wrecks. The usefulness of the species as a bioindicator organism is further discussed.

Net present value as an effective indicator leading to preventive maintenance of port mooring facilities

Net Present Value (NPV) is proposed as an indicator for decision-making processes entailed in the development of comprehensive maintenance strategies for mooring facilities of a port with consideration of variations in states of facility deterioration. In order to show the validity of the NPV as an effective indicator for a comprehensive maintenance strategy, the NPVs are compared through several case studies to the optimization results via consideration of a commonly used a life-cycle costs (LCC) indicator. In particular, the influence of uncertainty of deterioration progress is studied. The results show that NPV is an effective indicator for the comprehensive maintenance strategy of ports. Additionally, the NPV-optimized maintenance scenario, which indicated that preventative maintenance is the optimum strategy for port facilities, was found to be effective in incorporating uncertain factors, such as the state of deterioration.

Markov Chain-Based Stochastic Modeling of Chloride Ion Transport in Concrete Bridges

Over the last decade, there has been a lot of interest in models for evaluating and predicting the condition of existing bridges in North America due to the large number of them in an advanced state of deterioration. The models have been used to develop optimal strategies to prolong the service life of bridges, allocate limited financial and technical resources and maintain the required level of reliability of the bridges. The main process of deterioration of concrete bridges is corrosion of the reinforcing steel due to chloride ions and models for this type of deterioration can be classified as physical or statistical. The physical models describe the diffusion of chloride ions in concrete and chemical reactions while the statistical models, such as Markov chains, are used to model the progression of states of deterioration of the concrete structures. The physical models are appropriate to analyze deterioration processes for various structures and conditions of exposure but are computationally too demanding for the portfolio analysis of a large number of structures. Markov chain models have been extensively used for the latter purpose but require an extensive historical database to correctly estimate transition probabilities between deterioration states. The objective of this paper is to propose a novel procedure for estimating transition probabilities for Markov chain models by utilizing targeted simulations from physical models. The transition probabilities can be derived from specific climatological regions and concrete properties. The proposed framework provides the required input for portfolio analyses for a large number of different types of structures exposed to different climatological conditions. The procedure is demonstrated with the TransChlor® software and for a group of structures located in Montreal, Canada.

EGYPT’S FOREIGN POLICY UNDER ABDEL FATTAH EL-SISI

The article covers revolutionary changes in Egyptian foreign policy after the rise to power of Abdel Fattah el-Sisi. The authors note that the new President introduced a multidimensional policy, taking steps away from traditional dependence on the United States of America. To this end Egypt diversified suppliers for armed forces with the assistance of France and the Russian Federation, simultaneously expanding economic ties with China and the EU countries. The focus on the GCC monarchies that provide significant financial assistance to the regime also remains the important component of the Egyptian foreign policy. The article states that the aggravation of water shortages forces Egypt to conduct more active relations with African states, primarily with the Nile basin countries, but those attempts are “too little, too late”. The authors conclude that after exhausting all diplomatic means, Egypt can apply military force to protect its own water security against Ethiopia, but such policy will lead to direct clash with the United States of America and deterioration of Egyptian influence in Africa.

Environmental controls and reaction pathways of coupled de-dolomitization and thaumasite formation

Deteriorated concrete and interstitial solutions (IS) were collected from Austrian tunnels to elucidate potential connections between de-dolomitization caused by coupled alkali carbonate reactions (ACR) and thaumasite form of sulfate attack (TSA). A conceptual reaction model for the portlandite–CSH phases–dolomite–calcium sulfate–calcite–brucite–thaumasite system was developed based on experimental data, hydrochemical modelling, IS chemistry and apparent concrete compositions. During the initial stage of sulfate attack, ettringite and gypsum formation weakened the concrete's microstructure and initiated ACR. Leaching of hydrated cement phases resulted in IS with a pH ~ 12-13, which promoted incongruent dolomite dissolution. Infiltration of Ca–SO4–type ground water into the de-dolomitization zone facilitated calcite and brucite neo-formations at 13>pH>10.5 during advanced states of concrete deterioration and subsequently resulted in thaumasite precipitation at pH~8.7. In this contribution, the reaction mechanisms and environmental controls of de-dolomitization are discussed in relation to the durability of concrete under sulfate attack.

Carcass Age and Reproductive Costs forNicrophorus orbicollis(Coleoptera: Silphidae)

The life history costs of living in microbially dense environments can be high. To assess the importance of these costs for natural selection, it is necessary to know how costs vary with environmental conditions. Adult burying beetles prepare vertebrate carcasses of varying age and states of deterioration as a resource for their young. In the present study, Nicrophorus orbicollis Say females were presented with either fresh or aged (80 h) large carcasses (30-39 g) to examine effects on their lifetime reproductive success (four reproductive attempts) and survival. Reproductive success and survival were also measured for female offspring that developed on fresh and aged carcasses. Carcass age had no measurable effect on lifetime reproductive output or life span of either parents or their adult offspring. In a separate experiment using medium-sized carcasses (22-24 g), the reproductive performance of females in a single reproductive attempt was negatively affected by carcass age (13.9% less brood mass). The results suggest that the costs of using a single older carcass are relatively minor when measured over a lifetime. Alternative costs of using older carcasses and explanations for the complex antimicrobial traits of burying beetles are discussed.

Ultrasonic phased array technology for the non-destructive testing of marble sculptures

The medical ultrasonic phased array technology was modified for the non-destructive testing of marble sculptures and the feasibility of the approach was evaluated. For this purpose, 1 MHz, 64-channel phased array electronic and phased array transducers were developed. The specifications of the electronics and the transducers are presented and discussed. Ultrasound images of inner structures of a marble sculpture are presented. The problem of the acoustic matching layers for different states of deterioration is discussed and the developments in view of a suitable matching layer solution are presented. This matching layer is combined with a new coupling technique that protects the marble surface. The results of experiments on ultrasound phantoms and on a marble sculpture are presented.

Micromechanical Systems for the Mechanical Characterization of Muscle Tissue

This contribution describes the femtosecond laser ablation and mechanical characterization of small samples of skeletal muscles. Categories of tissue damage are defined and stiffness values related to the different states of deterioration. The stiffness values are obtained by tactile measurements with micromechanical force sensors and will be applied to the development of force-sensitive micro grippers for the characterization of biological tissues.

Advanced Spectral Imaging for Noninvasive Microanalysis of Cultural Heritage Materials: Review of Application to Documents in the U.S. Library of Congress

Hyperspectral imaging was originally developed for remote sensing and astronomical applications, but adaptations of this technology have been of great benefit to the preservation of cultural heritage. Developments in noninvasive analytical techniques have advanced the preservation of cultural heritage materials by enabling the identification and analysis of a range of materials, utilizing their unique spectral response to nondestructively determine chemical composition, and determining states of deterioration and change due to environmental conditions. When used as a tool for noninvasive characterization of cultural heritage, these spectral imaging systems allow the collection of chemical identification information about materials without sampling, which is a critical factor for cultural heritage materials. The United States Library of Congress has been developing the application of hyperspectral imaging to the preservation and analysis of cultural heritage materials as a powerful noncontact technique. It allows noninvasive characterization of materials, by identifying and characterizing colorants, inks, and substrates with narrow-band illumination to protect the object while also monitoring deterioration or changes due to exhibit and other environmental conditions. Contiguous illumination from the ultraviolet, visible, and infrared spectral regions allows the capture of lost, obscured, and deteriorated information. The resulting image cube allows greater capabilities for mapping and coordinating a range of complementary chemical and spectral analyses. The capabilities of this technique are illustrated by a review of results from analysis of the Waldseemüller World Map, the L'Enfant plan for Washington, D.C., and the first draft of the U.S. Declaration of Independence.

Inspección with non destructive techniques of a historic building: oratorio San Felipe Neri (Cádiz)

The main aim of this article is showing the results that have been obtained when non destructive techniques (ultrasound and thermography) are applied to a building with an important artistic and historical value. These non-destructive techniques have been applied in the inspection of the wooden roof structure to detect different states of deterioration, loss of density and defects. The aim is the assessment the state of the preservation of the wooden structure. A fieldwork has been carried out, where the two techniques have been applied together, ultrasound, an effective technique to establish the diagnosis of a wooden structure, and the thermography, a technique less tested in the in situ inspection of this material. The aim is checking the range and the real possibilities of using of each technique. In this sense, the methodology of ultrasound developed and published by the authors is applied and the thermography like in situ inspection tool, analysing additional difficulties and interference parameters not found in laboratory. The conclusions of this study show that the union of the ultrasound technique and the thermography is a good tool for on-site inspection of wooden structures and to assess their conditions allowing establishing a proper diagnosis. Thermography can detect different moisture contents and different materials and, on the other hand, ultrasound detects different states of deterioration or loss of density in specific areas with a high moisture content of the pieces.

El culto a San Millán en Valderredible Cantabria: Las Iglesias rupestres y la formación del Camino de Santiago (review)

Reviewed by: El culto a San Millán en Valderredible Cantabria: Las Iglesias rupestres y la formación del Camino de Santiago Mary Baldridge Kaplan, Gregory . El culto a San Millán en Valderredible Cantabria: Las Iglesias rupestres y la formación del Camino de Santiago. Cantabria: A. G. Quinzaños, 2007. 242 pp. As its title clearly suggests, Gregory Kaplan's book, El culto a San Millán en Valderredible, Cantabria: Las iglesias rupestres y la formación del Camino de Santiago, links the cave churches in southern Cantabria to the cult of San Millán and the pre-ninth century formation of the Camino de Santiago. Evidence suggests that pilgrimage to Santiago predates the discovery of Saint James's remains in the ninth century (Cunningham). This calls into question the motives for pilgrimage to (and through) northern Spain prior to the discovery of Santiago's remains, and the placement of the different routes that currently make up the Camino. Gregory Kaplan provides a partial answer to those questions in his study, showing evidence that San Millán's cult in Valderredible led to the establishment of a pilgrimage tradition along what would later become part of the Camino de Santiago. The Valderredible Valley hosts the largest grouping of cave churches in all of Spain. The region is home to more than fifty documented cave churches, necropolises, and other caverns, with the possibility that many more remain undiscovered ("Entrevista a Gregory Kaplan"). The dating of these sites, formed from natural caves that were further excavated to create churches, is difficult due to their states of deterioration. However, Kaplan focuses on the architecture and architectural dimensions of the churches. Basing his study on Jerrilynn Dodds's research showing that the architecture of Visigothic churches symbolically enacts Visigothic laws intended to extend control of the monarchy over the Hispano-Roman populace, Kaplan focuses on the dimensions of the horseshoe arch in each of these cave churches and the arch's relationship to the size and shape of the apse; he then compares those measurements to studies done on other Visigothic churches in order to arrive at approximate dates of construction. Kaplan begins his study with a brief historical section regarding the relationship between the Visigothic government and the Catholic Church. After the Visigothic monarchy converted to Christianity in the late sixth century, the Visigothic leaders formed a symbiotic relationship with the Church in order to legitimize their authority. This led to the creation of canon law that helped concretize the idea that Visigothic rule was divinely appointed. Changes in architectural norms for churches arose out of this new canon law. Dodds's aforementioned study of Visigothic churches shows how this relationship between church and state played out in the building agenda of the time; for example, the apses of these churches were partitioned from the rest of [End Page 247] the church to physically segregate them from the area open to congregants (Dodds 21-26). This characteristic is common to churches built in the Visigothic period and is seen as an identifying characteristic of that time. The next section of Kaplan's book compares the two extant versions of the life of San Millán. By far the better known version of Millán's life is Gonzalo de Berceo's Vida de San Millán de la Cogolla, which locates Millán's years of hermitage in the region of La Rioja, in the monastery that now bears his name. However, Berceo's version was written nearly six hundred years after Millán's death. For that reason, Berceo relied on the much earlier Vita S. Emiliani, written by Braulius of Zaragoza, which dates to some seventy years after Millán's death in 574. In spite of the fact that Berceo relied on Braulius's version, Kaplan draws attention to some of the notable discrepancies between the two versions. Brian Dutton recognized that many stories about San Millán from Berceo's time period were falsifications, created to benefit his monastery (viii). While Berceo claimed that Millán retired to a cave in what is today San Millán de la Cogolla de Suso (the upper monastery), the fact...

Preserved memory capacities in aged Lou/C/Jall rats

Although memory impairments are a hallmark of aging, the degree of deficit varies across animal models, and is likely to reflect different states of deterioration in metabolic and endocrinological properties. This study investigated memory-related processes in young (3–4 months) and old (24 months) Sprague–Dawley rats (SD), which develop age-linked pathologies such as obesity or insulin-resistance and Lou/C/Jall rats, which do not develop such impairments. In short- and long-term memory recognition tasks, old Lou/C/Jall rats were never impaired whereas old SD rats were deficient at 1 and 24 h latencies. The expression of N-methyl- d-aspartate receptors (NMDAR)-mediated synaptic plasticity in CA1 hippocampal networks shifted towards lower activity values in old Lou/C/Jall rats whereas long-term potentiation was impaired in age-matched SD rats. Age-related decrease in NR2A subunits occurred in both strains, extended to NR2B, NR1 and GluR1 subunits in older animals (28 months) but only in SD rats. Therefore, the Lou/C/Jall rats can be considered as a model of healthy aging, not only in terms of its preserved metabolism, but also in terms of cognition and synaptic plasticity.

Non-destructive assessment of parchment deterioration by optical methods

A non-destructive and non-invasive method for quantitative characterization of parchment deterioration, based on spectral measurements, is proposed. Deterioration due to both natural aging (ancient parchments) and artificial aging (achieved by means of controlled UV irradiation and temperature treatment) was investigated. The effect of aging on parchment native fluorescence was correlated with its deterioration condition. Aging causes fluorescence intensity drop, spectral shift of the main peak, and an overall change in the fluorescence spectral features. Digital color imaging analysis based on visible reflectance from the parchment surface was also applied, and the correspondent color components (RGB) were successively correlated with the state of parchment deterioration/aging. The fluorescence and color imaging data were validated by analysis of historical parchments, aged between 50 and 2000 years and covering a large variety of states of deterioration. The samples were independently assessed by traditional microscopy methods. We conclude that the proposed optical method qualifies well as a non-destructive tool for rapid assessment of the stage of parchment deterioration.

The Pacific's earliest painted pottery: an added layer of intrigue to the Lapita debate and beyond

Lapita pottery, the herald of the settlement of the wider island Pacific, turns out to have been painted with lime and clay, to give a red and white finish over the decorated surface. The find of a pot in Vanuatu, its sherds in different states of deterioration showed why painted Lapita has previously gone unrecognised. The author suggests that it was widespread from 1000 BC and reminds us that pottery was painted in China 7000 years ago.