Occurrence Of Disruption Research Articles

A multi-reservoir model for projecting drought impacts on thermoelectric disruption risk across the Texas power grid

Thermoelectric power plants often depend on multipurpose reservoirs to supply cooling water. Although reservoirs buffer natural hydrologic variability, severe droughts can deplete storage below critical thresholds, or to levels at which the effluent water temperature exceeds the environmental compliance requirement for cooling. This study explores the effects of projected climate change and drought on water storage at 30 major reservoirs in Texas. These reservoirs collectively provide cooling water for about two thirds of thermoelectric power capacity in the Electric Reliability Council of Texas (ERCOT) power grid. Multi-ensemble runoff projections generated from eleven downscaled hydroclimate simulations are mapped to key watersheds to create spatially correlated multi-reservoir inflow sequences. These data are used to drive reservoir storage simulations, which are linked to a metric of “capacity-at-risk” using critical reservoir thresholds. We find that projected impacts of climate change are mixed, with results indicating an increase in the occurrence of thermal disruption under only half of climate models. A critical threshold of 30% storage volume—applied to all reservoirs—results in disruption to about one fifth of ERCOT thermal generation during the most severe projected droughts. The study highlights an important role for detailed reservoir behavior simulations for capturing the effects of drought and climate change on thermoelectric plant performance.

Assessing dairy supply chain vulnerability during the Covid-19 pandemic

ABSTRACT Frequent occurrence of disruptions in the supply chain due to the Covid-19 pandemic has increased the supply chain vulnerability (SCU), which affects the performance and revenue generation of firms. If the commodity we are dealing with in a supply chain is of a perishable nature, then the situation becomes more complicated, as such products need restrictive storage and transportation facilities. The dairy supply chain is one such perishable product supply chain. This paper, thus, proposes a method to identify key drivers of SCU in a dairy SC followed by establishing a model using interpretive structural modeling (ISM) and a graph theory approach (GTA) to calculate the SCU Index. It is important to quantify the SCU for identifying major factors affecting it and then developing techniques to mitigate it. In order to quantify the SCU, first, the ISM model is used to identify the interrelation between drivers, and then an adjacency matrix is formed by using the interdependence, thereby adding inheritance of each driver. A variable permanent matrix is formed to calculate the SCU Index for the SC. This proposed approach will help managers in mitigating the adverse effects of COVID-19 on the dairy supply chain.

A causal inference approach to measure the vulnerability of urban metro systems

Transit operators need vulnerability measures to understand the level of service degradation under disruptions. This paper contributes to the literature with a novel causal inference approach for estimating station-level vulnerability in metro systems. The empirical analysis is based on large-scale data on historical incidents and population-level passenger demand. This analysis thus obviates the need for assumptions made by previous studies on human behaviour and disruption scenarios. We develop four empirical vulnerability metrics based on the causal impact of disruptions on travel demand, average travel speed and passenger flow distribution. Specifically, the proposed metrics based on the irregularity in passenger flow distribution extends the scope of vulnerability measurement to the entire trip distribution, instead of just analysing the disruption impact on the entry or exit demand (that is, moments of the trip distribution). The unbiased estimates of disruption impact are obtained by adopting a propensity score matching method, which adjusts for the confounding biases caused by non-random occurrence of disruptions. An application of the proposed framework to the London Underground indicates that the vulnerability of a metro station depends on the location, topology, and other characteristics. We find that, in 2013, central London stations are more vulnerable in terms of travel demand loss. However, the loss of average travel speed and irregularity in relative passenger flows reveal that passengers from outer London stations suffer from longer individual delays due to lack of alternative routes.

Teknik Interpolasi Bikubik untuk Memperbesar Gambar Hasil Pemetaan Suhu dari Sensor MLX90640 pada Praktikum Mikrokontroller

The occurrence of various disruptions and damage to equipment and electrical installations begins with a significant temperature increase in it. The temperature increasing in electrical equipment and installations will also increase the consumption of energy or power required. Previous technology used a temperature sensor and current sensor which had to be installed in the environment to be monitored. The temperature measurement system without touching the surface which is measured using infrared rays is a new breakthrough that really helps maintenance and repair. Also with the existence of a temperature sensor arranged in an array, it can map the existing temperature so that it can provide a better picture for analyzing the symptoms that occur, compared to using a temperature sensor that measures one point only. A temperature imaging camera is currently very expensive, making procurement a bit difficult for laboratories dealing with electrical equipment and installations. In this research, we will try to make an inexpensive temperature imaging camera using the MLX90640 sensor and the ESP32 microcontroller. Bicubic interpolation is used to enlarge the resulting image obtained by the MLX90640 sensor. The MATLAB program is used to simulate and create an overall temperature imaging camera system. Tested and compared with two other interpolation methods to ensure that bicubic interpolation can produce better magnified images.

Long-term outcome of non-stented tubularized incised plate urethroplasty for distal hypospadias repair: a complication analysis.

IntroductionAlthough it is apparently simpler to perform unstented tubularized incised plate (TIP) repair for distal hypospadias repair, consensus on feasibility of the use of unstented repair is still a matter of debate. Evidence reporting that unstented repair outcome is comparable to stented repair, especially in the long-term, is still weak due to reporting outcome inconsistencies, different study designs, inclusion of more than one technique, and inherent variability in meatal locations. Thus, we need a continuous and evolving assessment of the outcome of unstented repair to compile adequate evidence on the advantage of unstented TIP repair in distal hypospadias entity. The aim of this article was to review our long-term results with tubularized incised plate urethroplasty for distal hypospadias repair without a postoperative stent to determine its outcome which might justify its use.Material and methodsAfter a review of 154 patients with distal penile hypospadias, who underwent repair in Minia Urology & Nephrology University Hospital in the period between June 2015 and February 2018, we excluded cases who underwent MAGPI repair, redo cases and patients who failed to complete follow-up. We chose 72 patients who had only 1st time TIP repair and whom we could contact. A total of 44 out of 72 cases with stented repair were assigned to Group A, while 28 cases with unstented repair were assigned to Group B. Success was assessed based on Hypospadias Objective Penile Evaluation (HOPE) score by three separate senior pediatric urology consultants, independent of the surgeon and in the absence of high post-void residual urine (PVR). Average rate was calculated to be compared between both study groups.ResultsThere was no statistically significant difference regarding preoperative meatal location and age at repair and short-term complications. In the long-term; there was no statistically significant difference between the occurrence of urethrocutanous fistula (UCF, 4 vs 2 cases in Group A & B, respectively) and complete disruption (2 cases in each group) with need for redo repair. Results of total mean of HOPE score calculated showed no statistically significant differences between study groups and also failed to showed statistical significance on individual domains of HOPE score.ConclusionsUnstented TIP repair showed a similar outcome to stented TIP repair of distal hypospadias especially in the long-term despite a more troublesome early postoperative period.

Dynamic logistics disruption risk model for offshore supply vessel operations in Arctic waters

In harsh environments, offshore oil and gas support operations are subjected to frequent logistics and supply chain operational disruption, due to harsh environmental factors with their associated risks. To capture these stochastic influential factors and support related decision making, it is helpful to develop a robust and dynamic probabilistic model.The current study presents a proactive methodology that integrates the Pure-Birth Markovian process (PBMP) with the Bayesian network (BN) for the effective analysis of offshore logistics disruption risk. The PBMP captures the stochasticity in the failure characteristics of the engineering systems for estimating the time-evolution degradation probability. The BN explores the dynamic interactions among the most important offshore logistics influential factors to analyze the disruption risk in a harsh environment. The effects of influential factors’ non-linear dependencies are propagated and updated, given evidence on the degree of disruption. The level of logistics disruption is further assessed using cost aggregation-based expectation theory. The theory explores the incurred cost/economic risk under different operational scenarios. The proposed methodology is tested on an offshore supply vessel operation to estimate the likely operational disruption risk in terms of financial loss in a harsh operating environment. The most critical influential functions are assessed to establish their degree of impact on the logistics disruption. At the upper bound probability of disruption occurrence, an economic risk/additional incurred cost of US$2.38E+05 with a variance (σ2) of 3.05×109 was predicted. The result obtained suggests that the proposed methodology is adaptive and effective for dynamic logistics disruption risk analysis in harsh offshore environments.

The Roles of Prior Experience and the Location on the Severity of Supply Chain Disruptions

This study examines relationships between the location of supply chain disruptions (SCDs) within the supply chain, a firm’s experience with SCDs, and the disruption severity. Using organizational learning theory, we propose that an organization’s prior experience with SCDs will reduce the negative influence of future disruptions. However, the location of disruption occurrence (internal to the firm vs. external to the firm) also plays a vital role in the severity of future disruptions. We consider two measures of SCD severity to quantify the extent of negative influence on firms: (1) the initial loss of return on assets (ROA) and (2) the total loss of ROA over time. We empirically evaluate the performance of 262 publicly traded U.S. firms that experienced an SCD. Our study shows that the influence of internal and external SCDs on firms can be different when firms do and do not have experience with similar events. More specifically, the results show that when firms have not experienced a similar event in the past, internal SCDs are associated with a higher disruption severity than are external SCDs. The results also show that prior experience significantly decreases the disruption severity suffered by firms after internal SCDs.

Major impacts of weather events on the electrical power delivery system in the United States

Weather events are a major source of disruptions to the electrical power grid. This study examines the occurrence and variability of major weather-related electrical power disruptions by utilizing multiple datasets. Our results show that weather is responsible for 50% of all events and 83% of customers affected by them. Thunderstorms are responsible for 47% of weather-related events, while winter storms and tropical cyclones contribute 31.5% and 19.5%, respectively. The median restoration cost for utilities during major storms was ∼$12 million, with a median restoration time of 117.5 h (∼5 days). Tropical storms had the highest median number of customers affected, followed by thunderstorms and winter storms. Fewer mutual aid crews are utilized for thunderstorms than tropical or winter storms. The unique challenges that electrical utilities face from weather events are highlighted with case studies of Hurricane Harvey in Texas (2017), a 2011 snowstorm in the Mid-Atlantic, and severe thunderstorms in Alabama in 2011. We conclude by demonstrating that variations in the number of outage events (r = 0.79) and customers affected (r = 0.65) are primarily controlled by the number of storms. Weather-related power outages continue to be an important cause of power disruptions despite investments in storm outage prediction models and system hardening.

Generation of gravitational waves and tidal disruptions in clumpy galaxies

ABSTRACT Obtaining a better understanding of intermediate-mass black holes (IMBHs) is crucial, as their properties could shed light on the origin and growth of their supermassive counterparts. Massive star-forming clumps, which are present in a large fraction of massive galaxies at z ∼ 1–3, are among the venues wherein IMBHs could reside. We perform a series of Fokker–Planck simulations to explore the occurrence of tidal disruption (TD) and gravitational wave (GW) events about an IMBH in a massive star-forming clump, modelling the latter so that its mass ($10^8 \, {\rm M}_{\odot}$) and effective radius (100 pc) are consistent with the properties of both observed and simulated clumps. We find that the TD and GW event rates are in the ranges of 10−6 to 10−5 and 10−8 to 10−7 yr−1, respectively, depending on the assumptions for the initial inner density profile of the system (ρ ∝ r−2 or ∝ r−1) and the initial mass of the central IMBH (105 or $10^3\, {\rm M}_{\odot}$). By integrating the GW event rate over z = 1–3, we expect that the Laser Interferometer Space Antenna will be able to detect ∼2 GW events per year coming from these massive clumps; the intrinsic rate of TD events from these systems amounts instead to a few 103 per year, a fraction of which will be observable by e.g. the Square Kilometre Array and the Advanced Telescope for High Energy Astrophysics. In conclusion, our results support the idea that the forthcoming GW and electromagnetic facilities may have the unprecedented opportunity of unveiling the lurking population of IMBHs.

Risk Management Model in an Ecological Storage Facility

Purpose: The aim of the article is to develop a risk management model in an ecological storage facility. Design/Methodology/Approach: The research methodology used is the ICOM cube and the BPMN method, which give the opportunity to present elements enabling risk management in a warehouse facility using environmental principles. Findings: Implementation risk management model in an ecological storage facility enables sustainable development of the company, maintaining appropriate quality standards of the services provided and protection the surrounding environment. Practical Implications: The subject of ecology and risk factor management in warehouse management is an inherent challenge of logistics warehouse facilities. The combination of these two aspects is important for sustainable development in warehouse management. The presented models of risk management in warehouse management make it possible to reduce the occurrence of disruptions and protect the natural environment. Originality/value: The developed risk management model in an ecological storage facility enables the implementation of risk management procedures with sustainable development, which is an important aspect in the modern world. The implementation of the model by the examined entities will not only reduce the occurrence of risk factors, but also protect the natural environment. The combination of these two elements shows a new aspect of risk management in logistics companies.

Establishing a frame of reference for measuring disaster resilience

Due to the increasing occurrence of disruptions across our global society, it has become critically important to understand the resilience of different socio-economic systems, i.e., to what extent those systems exhibit the ability both to resist a disruption and to recover from one once it occurs. In order to characterize this ability, however, one must be able to quantitatively measure the relative level of resilience that a given system displays in response to a disruptive event. Such a measurement should be easily understandable and straightforward to implement, but it should also utilize a consistent frame of reference so that one can properly compare the relative performance of different systems and assess the relative effectiveness of different resilience investments. With this in mind, this paper presents an improved approach for measuring system resilience that supports better decision making by providing both consistency and flexibility across different contexts. The theoretical basis for the approach is developed first, and then its advantages and limitations are illustrated in the context of several different practical examples.

Flooding and mobility: a polish analysis

ABSTRACT The article contains the evaluation of indirect impact, and more precisely, effects related to traffic disruptions and the resultant changes in transport accessibility following the occurrence of a flood. The applied purpose of the analysis is to demonstrate the differentiation in spatial traffic distribution and changes regarding (time and potential) accessibility in three flooding scenarios for the Warta Water Region (the scenario 10% and 1% probability of a flood occurrence, and for the total destruction of stopbanks) in Greater Poland. The research showed that the occurrence of disruptions from untypical flooding impacts both the change in spatial distribution of traffic load within the road network and the speed at which its users can travel therein. This indicates the need to simulate various flooding scenarios in order to be better prepared for the occurrence of such a natural disaster.

Recall management in pharmaceutical industry through supply chain coordination

This paper is motivated by a real pharmaceutical supply chain (PSC) of Valsartan, facing two major concerns. First, implementing effective policies for product recall management due to disruption occurring in the manufacturing process, including impurity in raw material and packaging errors. Second, determining the optimal selling price and quality of raw material affecting the quality of the final compound, Valsartan, due to the effect of these decisions on Valsartan demand. In this paper, we analytically evaluate the impacts of production disruption, defective products recall, and decentralization among the members on the performance of the multi-echelon PSC. Moreover, for the first time, we address the context of channel coordination as a risk-mitigating strategy in case of disruption occurrence by proposing an altered revenue-sharing contract. Therefore, decisions are analyzed comparing decentralized, centralized, and coordinated decision-making structures under a range of scenarios. The results reveal that the proposed coordination scheme not only shares the incurred costs by disruption occurrence among all members but also improves their profitability compared to that of the decentralized structure, which leads to implementing effective recall management.

Recovery rate and factors associated with smell and taste disruption in patients with coronavirus disease 2019

PurposeTo determine the occurrence of olfactory and gustatory disruptions in COVID-19 patients, their association with demographic and clinical features and prognosis. Material and methodsThis observational cohort study involved consecutively diagnosed COVID-19 patients tested between March the 3rd 2020 and March the 24th 2020, in a geographically defined cohort area. All COVID-19 patients were evaluated in a University Hospital. The primary outcome of interest is the prevalence of smell and taste alterations, factors associated and recovery rate. Univariate and multivariate analysis by logistic regression was performed to detect factors associated to these symptoms. Results151 patients were included and 99 (65.6%) reported olfactory or gustatory symptoms. Olfactory dysfunction was reported by 75 patients (49.7%). Isolated anosmia was found in 2 patients (1.3%). Gustatory dysfunction was reported by 91 patients (60.3%). Factors associated with higher prevalence of smell dysfunction included age, sex, and comorbidities. The time to smell disruption development was significantly shorter in mild to moderate patients than in severe patients (p = 0.043). In 85.3% of patients with smell disruption, the symptom had been resolved in the first 2 months. 14.7% of patients remained symptomatic after 3 months of follow-up. ConclusionsOlfactory and gustatory dysfunction was common in COVID-19 patients. Smell disruption has high recovery rate and was associated with age, sex, and clinical severity. It may be beneficial to investigate the appearance of taste and/or smell disruptions in individual patients, with respect to diagnosis and prognosis.

Perilunate Injury with Concomitant Short Radiolunate Ligament Disruption: Prevalence and Surgical Outcomes-"An Unusual Perilunate Injury Variant".

Background In the classic description of perilunate injuries, the short radiolunate ligament (SRL) remains intact. Objective This study was aimed to determine the occurrence of SRL disruptions with perilunate injuries and review the clinical and radiographic outcomes after surgical management. Patients and Methods A retrospective review was conducted for patients who sustained a perilunate injury and a concomitant disruption of the SRL at a single-level-1 trauma center between January 2013 and January 2017. Patients with the combined injury pattern were compared with those with perilunate injury alone without SRL injury during the study period. Outcome measures included pain scores (visual analogue score), wrist and forearm range of motion, patient's return to their former occupation, and multiple radiographic parameters. Results Twenty-seven patients were treated operatively for a perilunate injury. Eight of these patients (30%) were found to have associated disruption of the SRL. When compared with patients with perilunate injury alone, these patients had a lower rate of return to work (57% [4 of 7] vs. 92% [12 of 13]), a significantly longer mean length of time to return to work (5.9 vs. 3.8 months), and a higher rate of associated upper extremity injury (75% [3 of 8] vs. 16% [3 of 19]. Conclusion Combined SRL disruption and perilunate dislocation or fracture dislocation represent a high-energy variant from the classic description of a perilunate injury. A heightened awareness for this combined injury pattern should be maintained when treating patients with perilunate injuries. Level of Evidence This is a Level III, prognostic study.

A resilience assessment approach for power system from perspectives of system and component levels

This paper proposes a novel resilience assessment approach for power system. Two resilience indices are developed from the perspectives of the system and individual component levels, respectively. The former one quantifies the resilience of a power system in a system-wide manner, while the latter is intended to assess the individual component through the pre-disruption and post-disruption indices. Specifically, the pre-disruption index is used to determine the weak points of the system before the occurrence of disruptions, while the post-disruption index is for designing the optimal restoration strategies. We advocate the use of impact-increment-based state enumeration method to calculate the presented indices in an efficient way without loss of accuracy. Numerical results carried out on the IEEE RTS-79 test system and the IEEE 118-bus system validate the effectiveness of the proposed approach and indices.

Developing natural-gas-supply security to mitigate distribution disruptions: A case study of the National Iranian Gas Company

Stable natural-gas supply and reduction of distribution disruptions play a crucial role in the socio-economic wellbeing and support sustainable development. The socio-technical nature of disruption compels implementation of an interdisciplinary perspective using a lens of supply-chain management. In this manner, disruption drivers are present in the internal, network, and environmental categories. Further, a quantitative method is necessary to evaluate and minimize the occurrence and effect of disruptions by promoting capability development. Therefore, natural-gas-supply security (NGSS), as a hierarchical and multi-dimensional construct, is considered to develop these capabilities. The effect of NGSS on mitigating gas-distribution disruptions, which is based on the contingency theory, is investigated to shed light on what a company should do to mitigate disruptions. Structural equation modeling is also applied to analyze the data collected through a survey questionnaire in Tehran Province Gas Company. The results show that NGSS, in the context of disruption mitigation at the company level, consists of three main dimensions: availability, infrastructure, and governance. The findings suggest that availability can be achieved by not only a sufficient supply but also efficient energy use. Further, behavioral and technological changes are essential. In addition, policies and regulations are not sufficient to develop governance; thus, structure, systems, and monitoring should be emphasized. The conclusion of this study provides an empirical basis and some insights into capabilities that aim to mitigate disruptions. These capabilities can provide reinforcement to transparency, trust, risk-management culture, and integrated supply–demand approach to prevent fluctuations in gas availability, thus promoting infrastructure that deals with environmental sustainability and subsequently addresses disruptions.

Algorytm wsparcia strategii tbm w wielomaszynowych systemach wytwórczych

The execution of production processes in real manufacturing systems is associated with the occurrence of numerous disruptions, which predominantly revolve around technological machine failure. Therefore, various maintenance strategies are being developed, many of which tend to emphasise effective preventive measures, such as the Time-Based Maintenance (TBM) discussed in this paper. Specifically, this publication presents the time-based machine failure prediction algorithm for the multi-machine manufacturing environment. The Introduction section outlines the body of knowledge related to typical strategies applied in maintenance. The next part describes an approach to failure prediction that treats processing times as makespan and is followed by highlighting the key role of historical data in machine failure management, in the subsequent section. Finally, the proposed time-based machine failure prediction algorithm is presented and tested by means of a two-step verification, which confirms its effectiveness and further practical implementation

Quercetin-induced yeast apoptosis through mitochondrial dysfunction under the accumulation of magnesium in Candida albicans

Latterly, the upsurge in use of antifungal drugs has brought about the emergence of several drug-resistance strains, making it skeptical to continue relying on current therapeutic regime. In the necessity of resistance-free antifungal agent, flavonoids presented possibilities of replacing existing drugs, displaying antifungal activity against pathogenic fungi. Among them, quercetin, one of the most representative flavonoids, exhibited antifungal activity against Candida albicans. To inspect the further understanding regarding quercetin, the antifungal mode of action of quercetin was investigated. In the initial step, the apoptosis was monitored after quercetin treatment. Moreover, intracellular levels of Mg2+ was assessed and was determined that Mg2+ increase occurred under the influence of quercetin. In addition, several features of mitochondrial dysfunction were monitored. Mitochondrial dysfunction triggers decrease in mitochondrial redox levels and leads to disruption in mitochondrial antioxidant system. Increased intracellular ROS and decreased intracellular redox levels were also displayed, indicating the occurrence of overall disruption in antioxidant systems. Sequentially, DNA fragmentation was observed and this DNA damage in turn induces apoptosis. In analyses, hexaamminecobalt(III) chloride (Cohex) was applied to inhibit Mg2+ transport between cytosol and mitochondria. Cohex attenuated the effects induced by quercetin, which demonstrates that the presence of Mg2+ is essential in quercetin-induced apoptosis.

Experimental research into collisions of homogeneous and multi-component liquid droplets

This paper presents the results of experiments recording the collision characteristics of droplets of various liquids with each other in a gas medium. We use water-based compositions typical of fuel, petrochemical, and heat and mass transfer technologies: solutions, emulsions, slurries, immiscible two- and multi-component liquids. The study discusses how droplet dimensions, velocities, impact angles, component concentrations and properties affect interaction regime as well as the number and size of child droplets. Threshold conditions are analyzed for the occurrence of bouncing, separation, coalescence, and disruption of droplets. Basic hypotheses are formulated as to why the collision characteristics of single-component droplets in a gas differ from those of highly heterogeneous multi-component ones. We use the interaction regime maps based on the dimensionless processing of experimental results through angular and linear impact parameters, Weber, Reynolds, Ohnesorge, and capillary numbers. Collisions can provide major atomization, in which the relative surface area of the liquid increases 2–6 times. The values of these parameters are influenced by droplet velocity and size, component type (solid or liquid), concentration and properties (density, viscosity, surface tension), as well as temperature and role (projectile or target) of homogeneous and multi-component droplets.