Disastrous Accidents Research Articles

54 Validation of Infrared Thermography for Prediction of 21-day Burn Wound Healing

Abstract Introduction Although trained specialists easily identify most full and superficial partial thickness burn injuries, deep partial-thickness injuries present a true challenge to the clinician. Various imaging modalities to assess perfusion and determine healing potential include skin biopsy with histology, laser doppler imaging, active dynamic and static infrared thermography, vital dyes, indocyanine green video angiography and others. Prior studies indicate, with small clinical and animal studies, forward looking infrared is a valid tool to assess healing potential and 21-day healing within the first 48 hrs after presentation. The aim of our study is to determine if an absolute increase or decrease in temperature (°C) measurements across a burn wound in a large clinical cohort correlates with 21-day healing after 48 hrs from time of injury. Methods After informed photo consent was obtained, thermographic images were captured at presentation, 24hrs, and 48hrs from patients admitted to our center between October 2018 and August 2019. Thermographic images were reviewed and temp measurements obtained using a linear vector through the wound. Next we determined if patients healed within 21 days. Data collected includes demographic data, burn characteristics, injury site (based on Lund Browder segmentation) and wound temp (average, minimum, maximum). Data was analyzed using Wilcoxon rank sum test with continuity correction. Results We reviewed images for 159 burn sites from 29 patients, the largest image set to be reviewed to date. The cases were 84% male, the mean and range was 33.1 years (1.7 – 70) for age and 25% (2 – 54.5) for TBSA. We found an average temp difference between 24 hrs – 48 hrs (p-value= 0.007) was significant, and no significant difference in average temp change when evaluating admit – 24 hrs (p-value=0.053) and admit – 48 hrs (p-value=0.316), consistent with predictions of prior studies. Average temp from admit – 24 hrs decreased by 0.86°C in healed (n=48) vs non-healed (n=91); increased on average by 1.25°C in healed (n=39) vs non-healed (n=74) from 24 hrs – 48 hrs; and showed a modest decrease by 0.3°C in healed (n=50) vs non-healed (n=82) when comparing admit 48 hr temp. Conclusions These data demonstrate that burn wound temperature difference between 24 and 48 hours after admittance as measured by infrared thermography correlates with clinical outcomes and 21 day healing. Applicability of Research to Practice Infrared thermography is a validated tool to assess burn depth after 48 hrs. In the future, this modality may impact triage in the military, rural, accidental and non-accidental disasters.

A thermodynamic model for predicting transient pressure evolution in response to venting and vaporization of liquefied gas under sudden release

Liquefied gases in energy supply chain suffer the risks of disastrous accidents (e.g. boiling liquid expanding vapor explosion) normally resulted from a sudden release. The boiling response and its associated pressure transient under sudden release determine the severity of the accident, and are crucial for assessing the consequences of the sudden release. For predicting the pressure transient, a thermodynamic model of the liquefied gas under sudden release is presented in this paper. A three-stage modelling approach is proposed to describe the entire thermodynamic process after sudden release according to the venting and boiling behaviors of liquefied gas. A set of differential-algebraic equations are established based on mass and energy conservation for predicting the transient thermodynamic parameters. Comparisons of model predictions with experimental data show a consistent trend in pressure-time histories, with relative deviations of average pressures less than 5.78 %. The results show that the minimum pressure point has a time delay compared to the boiling inception point. The increase of release pressure and the decrease of vessel scale will strengthen the pressure rebound, and the increase of vent area will lead to higher depressurization and re-pressurization rate.

Estimating traffic change in accidental regional node failure for Asia pacific IP networks

Connectivity seems to be one of the significant features of today’s life. People rely on their technology in almost every aspect of their daily living. They also depend on this technology to be accessible anytime and anywhere. It is true that technology has touched every feature of today’s life. However, it is the networks that allowed this touch to reach almost everyone, regardless of who or where they are. Disasters stand for the oldest challenges that ever faced humanity. Since societies are extremely dependent on the technology, it is imperative to face the challenge in terms of technological communication systems. In this paper, the Accidental Disaster Network Impact Model is used to study the impact of a regional computer network failure triggered by an accidental disaster on the surviving network. The main aim is to study the percentage of change in traffic and lost traffic in node failure scenarios. This research estimates the change in traffic in cases of single node failure and double node failure. Also, it addresses the case of partial node failure in which only part of the communication ability is lost. The research also generates a simplified network map that represents the regional network of Asia Pacific.

Evaluation of roadway water hazard level based on extension connetion cloud model

Accurately assessment of water hazard level in coal mine can improve the water hazard prevention and control in coal mine and reduce the occurrence of water inrush disaster. Based on the theoretical and practical study of coal mine water disaster accidents, a water disaster assessment index system was established. The transformation between qualitative and quantitative indicators was realized by the matter-element extension theory and the cloud model, the state value of the index and the corresponding risk grade membership value were determined by the connection cloud model, and the method of game theory was used to value the comprehensive weight of evaluation index to reduce the randomness and subjectivity in the determination of weight. Based on the principle of distance similarity, the evolution trend of risk can was estimated to strengthen the early warning of trend risk. The application in Feicheng mining area showed that the extension connection cloud model evaluation is appropriate to the evaluation of coal mine water hazard, and the quantitative characterization of water hazard risk is of great significance to guide coal production to be safe.

Optimal Model of Fire Fighting and Rescue Operational Plan Based on Utility Function

The fire brigade was a specialized and militarized team that fighted fires and other disasters, whose main duties were to dispose of fires and other disasters in order to protect people’s lives and property. Under the new situation, with the increasing complexity of disaster accidents and the status quo of the equipment of the fire brigade, firefighting and rescue work presented the characteristics of complexity, diversity and arduousness. Therefore, in order to complete the firefighting rescue faster and better, and avoid the disadvantages of the command, it was particularly important to carry out the plan optimization. In view of this, an optimization model of firefighting and rescue operational plan was proposed by this paper to determine the good and bad of the plan by using the utility function model to do quantitative calculation. The construction principles and specific calculation steps of the utility function model were firstly introduced by the paper. Then the actual case was combined with to establish the index system of a fire fighting and rescue optimal plan to solve the utility function value. Finally, the weights and utility function values were used to determine the comprehensive evaluation value, in order to select the best operational plan. The feasibility of the plan waiting for the selection was transformed by this model through the utility function, making it more comparable and easy to optimize the plan. The determination of the optimal plan improved the decision-making ability of the commander, and the operation mechanism to guide and improve the firefighting rescue, thereby to effectively.

Experimental research on explosion resistance of masonry structures reinforced with modified polyurea elastomer

In order to improve the explosion resistance performance of masonry structures during the terrorist attacks and accidental disasters, clay brick and concrete block walls are reinforced by modified polyurea materials. Explosion resistance tests of these two kinds of masonry wall structures are carried out to analyze the failure modes and anti-explosion effects of reinforced masonry walls under different thickness and reinforcement modes. The results show that modified polyurea elastomer not only has good spraying adhesion and compatibility with the base material surface, but also can effectively encapsulate the explosive debris generated by the back blasting surface of the masonry wall under explosive load, which reduces the deformation and displacement of the wall.

Assessment of Cascading Accidents of Frostbite, Fire, and Explosion Caused by Liquefied Natural Gas Leakage

Liquefied natural gas (LNG) leaks often lead to cascading accident disasters, including vapor cloud release, explosion, fire, and toxic gas release. The origin and evolution of each accidental disaster must be considered when assessing safety. This paper discusses the safety assessment project of an LNG gas storage station in Xuzhou, China. Multiple conceivable disasters due to the leakage of LNG storage tanks are simulated and analyzed using the computational fluid dynamic software FLACS. We studied different wind speeds interacting with the flammable vapor cloud area and creating frostbite in areas of low temperature. Diffusion simulations of vapor cloud explosion (VCE), thermal radiation, and the distribution of toxic substances were performed. The overpressure‐impulse criterion was used to calculate the influence range of VCE. Heat flux, heat dose, and heat flux‐heat dose criteria were used to calculate the safe distance for personnel in the event of fire. Based on the calculation results of the three latter criteria, this paper recommends using the heat flux criterion to evaluate fire accidents. The danger zone of each accident was compared. VCE accidents yielded the largest area.

사회적 재난에 의한 간접외상 경험에서의 개인차

사회적 재난에 의한 간접외상 경험에서의 개인차

Applications of a robust particle tracking velocimetry algorithm in the multiple-parametric measuring system for coal exploration industry

With the gradual increase in the average exploration depth of domestic coal industry, the conflict between deep coal exploration technology and exploration requirements is becoming increasingly prominent. A series of exploration disaster accidents caused by geological disasters require a high level of survey technology before the deep coal exploration. In this study, a high-resolution single hole measuring system for aquifers in coal seam is proposed. The entire system can be divided into two parts: hardware and software. The hardware probe integrates various sensors for different physical parameters using optical fibre to communicate with the controlling part above the ground. The home-made software is then used to receive and process the signals of temperature, pressure and orientation, as well as the instantaneous image sequence of aquifer with flowing contaminants. A home-made novel particle tracking velocimetry algorithm based on Voronoi diagram is used as the core algorithm to analyse the image sequence and obtain the magnitude and direction of flow at the measuring spot of aquifer. After practical tests, the system is confirmed to be able to effectively monitor the hydrological conditions of the aquifer in coal seam. Therefore, the proposed algorithm can be applied to the evaluation of hydrogeological conditions before well establishment for coal-exploration and to the prevention of potential dangers during the exploration work.

Statistical analysis the characteristics of extraordinarily severe coal mine accidents (ESCMAs) in China from 1950 to 2018

Extraordinarily severe coal mine accidents (ESCMAs) are characteristized by thirty fatalities or more in one accident. In this paper, such ESCMAs are analyzed using 188 cases which occurred in Chinese underground coal mines. The analysis shows that the number of ESCMAs and the death toll have decreased steadily over time. Gas explosions, mine water inrushes, and coal dust explosions are the three major types of ESCMAs. Among the causes of ESCMAs, inadequate implementation of safety measures, deliberate violations and electromechanical equipment faults are the three top causes of ESCMAs, accounting for 27.13 %, 21.81 %, and 15.96 % of incidences, respectively. Meanwhile, ESCMAs frequently occur in the heading face, especially gas explosions, mine water inrushes and coal and gas outbursts. Furthermore, ESCMAs reoccur often in certain provinces, such as Shanxi, Henan and Heilongjiang, and mostly during November and December in each year. The results of statistical studies have presented useful information for the prevention of ESCMAs in order to reduce the probability of such disastrous accidents.

Determining Structural Damage of Stone Curtain Walls by Dynamic Method

Dry hanging stone curtain wall is widely used in the building envelopes, but it was of ten deemed as a safety risk. The damage of the back anchorage structure may result in the urban disaster accident due to the falling down of the tone panel. There is no yet effective detection method because the damage part is hidden behind the panel. In this paper, a dynamic detection method is presented to monitor the damage degree of the anchorage structure on the back of the panel and to determine the damage location. Experiments indicate that the first three steps of natural frequency of the stone panel declined, with the increase of the damage degree of the anchorage structure. The degradation of the natural frequency can be used to identify the degree of back connection damage. In addition, the relationship between the damage position of the back connection and the modal parameters of the stone was investigated. It was found that the change of the damaged location significantly affected the modal vibration of the stone panel and the relative discriminant method is proposed to determine the damage position.

Proposed Improvements to the Safety Inspection System: An Analysis of the Current Status of Building Disaster Accidents and Safety Inspection Systems

Proposed Improvements to the Safety Inspection System: An Analysis of the Current Status of Building Disaster Accidents and Safety Inspection Systems

Analysis on Professional Team Formation for Chemical Firefighting Based on Petrochemical Fire Treatment in A Certain City

The petrochemical disaster accidents nowadays are often characterized in large scale and great complexity, showing features of abrupt happening, severe damages, high requirements on firefighting techniques, great disposing difficulties, and long firefighting time. The technical and tactical research on petrochemical fire disaster disposition has always been a vital subject of the fire brigade. In this paper, in view of firefighting combat estimation, technical and tactical application and equipment model selection under different fire disaster conditions, the basic combat formation and equipment standard were proposed according to the petrochemical industry layout and structural features of a certain city. It is significant to further standardize the formation of daily training and cross-region joint operation. Meanwhile, it can effectively enhance the professional ability and level of the firefighting team in disposing petrochemical accidents.

The Multi-Varieties Small-Batch Gas Monitor Flexible Digital Job Shop Design and Integration Technology Research

With the large-scale construction of city gas pipeline, increasing natural gas pipeline leakage accident disasters caused by the gas monitor is an important on-line measurement instrument for the safety operation of the network of natural gas, which has the characteristics of multi-varieties, style complex, complex procedures, automatic production, low digital level by making multi-varieties small-batch gas monitor as the main the mode of production. In order to solve that the traditional digital manufacturing job shop cannot meet the modern multi varieties and small-batch production of gas monitor manufacturing requirements, based on the complex production process of digital equipment, digital control, digital key technology, it proposes a gas monitor job shop solution based on intelligent manufacturing, construction of the implementation of the integrated framework and implementation activities of information flow model to realize the bottom equipment layer, design and manufacture of middle management and intelligent control layer. It has proved that multi-varieties small-batch of digital manufacturing job shop manufacturing process and development has a good application effect and can provide a reference model for the multi varieties small-batch manufacturing precision instruments in the production, greatly saving the production casting time cost, production cost and resource cost.

Application of natural weathered red-bed soil for effective wall protection filter-cake formation

Abstract In the context of slurry use for maintaining pressure and stabilizing wall protection during shield opening, diaphragm wall excavation and deep drilling to further prevent disaster accidents in civil engineering projects, a method to slurry using the natural weathered red-bed soil as the primary material is proposed, which is directly stirred with water without the addition of any other materials. Orthogonal tests are designed with the rate of change of the air filtration volume rate, effective airtightness time, and water content as the evaluation indexes. Fully transparent and high-pressure filter-cake airtightness tests are carried out. Results indicate the time of filter-cake formation is determined by the change rate of air filtration volume rate in the range between 0.020 and 0.025 L/(m·min)2. As regards the degree of influence on filter-cake formation, density exerts the greatest influence, followed by viscosity and less-than-1-mm-sized particle content. Further, the optimum density/viscosity/less-than-1-mm-size particle content combination of the slurry is determined to lie in the ranges of 1.83–1.95 g/cm3/13–21 Pa·s/45–60%. Moreover, it is found filter-cake damage is closely related to water content. With similar properties to the artificial, wide distribution of natural sources, low cost, and sample process, this materials is expected to be widely applicated.

Measurement and prediction of granite damage evolution in deep mine seams using acoustic emission

With unceasing increase of mining depth and development intensity, mining disasters such as rock burst have been increasing frequently, which often result in catastrophic accidents. Therefore, it is imperative to accurately forecast underground disasters. Previous research has suggested that the combination of drill-hole pressure relief and acoustic emission (AE) monitoring serves as an effective measure method towards the forecasting and prevention of disastrous accidents. However, the AE evolution mechanism of underground rock damages remains a challenge; more specifically, the relationships among the drilling hole positions, depths and diameters, and the stress–strain and AE characteristics of the rocks are discussed little in the literature. In order to bridge this research gap, the particle flow code (PFC2D) is employed to systemically investigate the hidden patterns among the mechanical properties, AE and damage evolution of the rock mass with different positions, depths and diameters of the drilling holes. Analysis results demonstrate that the drilling position influences the rock stress–strain and AE characteristics in the plastic deformation stage and the residual stage while the hole depth affects the drilling process. More specifically, the initial AE strength, AE impact at the peak moment, AE fluctuations and induction time are significantly influenced by the drilling position and depth. Furthermore, the drilling position and depth change the evolution law in the damage acceleration and stable development stages, while the hole diameter has little effect on the AE signal during the rock drilling process.

Characteristics of landslide-debris flow accumulation in mountainous areas

Landslide-debris flow is a sudden geological hazard in mountain areas, which is characterized with large scale, fast speed and wide impact range, and often causes disastrous accidents. In this study, an indoor sliding chute test was used to study the movement process of the landslide-debris flow and its accumulation pattern in the valley, taking into account the initiated gradient and particle size distribution. Besides, the model test was reproduced by PFC and the numerical models were constructed to fit the actual situation of landslide-debris flow. The results show that the collision of particles occurs during the movement of landslide-debris flow, and obvious sorting phenomena occur in the final deposit. Coarse particles distribute in the front and surface of the deposit while fine particles distribute in the back and bottom. The initiated angle has a certain effect on the morphology of the deposit: larger initiated angle makes the deposit closer to the opposite bank of the valley. Particle gradation has a significant impact on the form and distribution of deposit as well, with the increase of the proportion of coarse particles, the deposit of fine particles shrinks to the center of the rear edge, the profile of the deposit is more flat and uneven, the deposit is closer to the opposite bank of the valley, and the angle of the deposit profile increases significantly.

An Alternative Method for Urban Inhabitants to Reach Out Logistics’ Center (Supermarkets and Other Services), to Become Independent of Automobiles, With an Objective to Reduce Prices, Disastrous Accidents, Air Pollution, Traffic Jams and etc…

Urban inhabitants' access to the items and undertakings without depending on the lane's traffic is a new method to help resolve some of the urban and environmental issues. The well-being of a city and its suburbs, access to supermarkets, school, firms, and other services, is an essential factor for a family who wishes to move to a new neighborhood. Traffic additionally offers an upward shove by high prices for the financial system through delays brought on using congestion. Every year, more than three million vehicles are added into the auto collection of Europe. With the gradual development and evolution of digital online shopping and other services regarding community, interiors do reduce trips. Serving to a client after receiving an order by a faster, safer method, regardless of time or outside climate reducing the cost of delivery with the help of robots is a new logistic transferring underground corridor system, between Urban occupants and great industrial complexes, supermarkets, prescript stores, superfluous portion shops, book shops, library, pizza shops. Etc...this article aims to introduce a new alternative logistic underground corridor method for metropolitan disturbed by cars, long roads to reach out logistics they need, air and sound pollution, regional security matters and etc.

Theoretical and technological exploration of deep in situ fluidized coal mining

Mining industries worldwide have inevitably resorted to exploiting resources from the deep underground. However, traditional mining methods can cause various problems, e.g., considerable mining difficulty, environmental degradations, and frequent disastrous accidents. To exploit deep resources in the future, the concept of mining must be reconsidered and innovative new theories, methods, and technologies must be applied. To effectively acquire coal resources deeper than 2000 m, new theoretical and technological concepts about deep in situ fluidized mining are required. The limits of mining depth need to be broken to acquire deep-coal resources in an environmentally friendly, safe, and efficient manner. This is characterized by ‘There are no coal on the ground and no men in the coal mine’. First, this paper systematically explains deep in situ fluidized coal mining. Then, it presents a new theoretical concept, including the theories of mining-induced rock mechanics, three-field visualization, multi-physics coupling for in situ transformation, and in situ mining, transformation and transport. It also presents key technological concepts, including those of intelligent, unmanned, and fluidized mining. Finally, this paper presents a strategic roadmap for deep in situ fluidized coal mining. In summary, this paper develops new theoretical and technological systems for accomplishing groundbreaking innovations in mining technologies of coal resources in the deep underground.

Hellish Traffics Congestion Caused by Vagabond Diversity, Ignorance Simply to Applying a Tunnel in Urban Space to Exhaust

The urban dodge is an empiric then politics method concerned including the development or plan about land-use, or the timbered environment, permanency, certain objects such as street furniture In some countries called urban fixed or mobile elements (components). On a global scale do not follow a certain installation rule. Despite urban founder testimonial, their settlement in urban space is irrational, either on the urban designer, local municipal, or others. According to the fact we encounter disorder, not only disastrous accidents, or air pollution, or traffic blockades. But also how much the automobiles themselves space occupy and even worse global ecological issues. In this article, we discuss underground tunnels. Despite using, traffic lights at a 4-way junction presented under the intelligent inspection mechanism. The vehicle density waiting behind the red-light duration is causing traffic blockages and thus wastes of time. There are serious demands for Tunnel which is a fixed urban component on intersections to lubricate an end to traffic jams. Despite using, traffic lights at a 4-way junction presented under the intelligent inspection mechanism. The vehicle density waiting behind the red-light duration is causing traffic blockages and consequently wastes of time. Creation of air pollution and etc. There are serious demands for Tunnel which is a fixed urban component on intersections in order to lubricate an end to traffic jams. Formidably traffic blockage frequently emerges because of the traffic light, auto collisions, the resilience of the community will keep appreciably improved by new tunnel furnishes an alternative crossing. This article intends to propose a scientific natural draft method of ventilation never used before.