Weapon effectiveness and the shapes of damage functions

This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with the correct shape factor.First,cookie-cutter damage functions are redefined to preserve the shape factor of and to have the same lethal area as the corresponding Carleton damage function.Then,closed-form solutions of the effectiveness methods are obtained by using those cookie-cutter damage functions and the Carleton damage function.Finally,the closed-form solutions are applied to calculate the probability of damaging a point target and the expected fractional damage to an area target for several attack scenarios by using cookie-cutter damage functions and the Carleton damage functions with different shape factors.The comparison of the calculation results shows that using cookie-cutter damage functions or the Carleton damage function with a wrong shape factor results in quite significant differences from using the original Carleton damage function with a correct shape factor when weapon’s delivery error deviations are less than or comparable to the lengths of the lethal area and the aim point is far from a target.The effectiveness methods improved in this paper will be useful for mission planning utilizing the precision-guided munitions in circumstances where the collateral damage should be reduced.

Regional Rainfall Damage Functions to Estimate Direct Economic Losses in Rainstorms:A Case Study of the 2016 Extreme Rainfall Event in Hebei Province of China

Developing a regional damage function to quickly estimate direct economic losses(DELs)caused by heavy rain and foods is crucial for providing scientifc supports in efective disaster response and risk reduction.This study investigated the factors that infuence regional rainfall-induced damage and developed a calibrated regional rainfall damage function(RDF)using data from the 2016 extreme rainfall event in Hebei Province,China.The analysis revealed that total precipitation,asset value exposure,per capita GDP,and historical geological disaster density at both the township and county levels signifcantly afect regional rainfall-induced damage.The coefcients of the calibrated RDF indicate that doubling the values of these factors leads to varying increases or decreases in rainfall-induced damage.Furthermore,the study demonstrated a spatial scale dependency in the coefcients of the RDF,with increased elasticity values for asset value exposure and per capita GDP at the county level compared to the township level.The fndings emphasize the challenges of applying RDFs across multiple scales and highlight the importance of considering socioeconomic factors in assessing rainfall-induced damage.Despite the limitations and uncertainties of the RDF developed,this study contributes to our understanding of the relationship between physical and socioeconomic factors and rainfall-induced damage.Future research should prioritize enhancing exposure estimation and calibrating RDFs for various types of rainfall-induced disasters to improve model accuracy and performance.The study also acknowledges the variation in RDF performance across diferent physical environments,especially concerning geological disasters and slope stability.

Do new neurons contribute to functional reorganization after brain damage?

The finding that adult neurogenesis occurs constitutively in the brain was a breakthrough in neuroscience and soon gained attention as a possible mechanism for neurorepair after brain damage. In a recent study we show that the dentate gyrus （DG） reorganizes anatomically over neurons undergo maturation time after damage, while new and activate in response to a contextual fear memory recall （Aguilar-Arredondo and Zepeda, 2018）. These findings provide new evidence on the possible role of neurogenesis in cognitive recovery after brain injury.

Explicit Exact Solution of Damage Probability for Multiple Weapons against a Unitary Target

Abstract We study the damage probability when M weapons are used against a unitary target. We use the Carleton damage function to model the distribution of damage probability caused by each weapon. The deviation of the impact point from the aimpoint is attributed to both the dependent error and independent errors. The dependent error is one random variable affecting M weapons the same way while independent errors are associated with individual weapons and are independent of each other. We consider the case where the dependent error is significant, non-negligible relative to independent errors. We first derive an explicit exact solution for the damage probability caused by M weapons for any M. Based on the exact solution, we find the optimal aimpoint distribution of M weapons to maximize the damage probability in several cases where the aimpoint distribution is constrained geometrically with a few free parameters, including uniform distributions around a circle or around an ellipse. Then, we perform unconstrained optimization to obtain the overall optimal aimpoint distribution and the overall maximum damage probability, which is carried out for different values of M, up to 20 weapons. Finally, we derive a phenomenological approximate expression for the damage probability vs. M, the number of weapons, for the parameters studied here.

A method to determine the shell layout scheme for equipment battlefield damage tests under artillery fire

In this paper,a new method for determining the shell layout scheme is proposed,which can make the equipment damage data by the battlefield damage test resemble as close as possible the actual combat data.This method is based on the analysis of the impact point distribution and effective damage area of equipment.In order to obtain the position of the impact points,an impact point distribution model under artillery fire was established.Similarly,in order to obtain the effective damage area of equipment,the concepts of generalized damage area and task-based equipment functional damage probability were demonstrated,and the corresponding calculation model was established.Through case analysis,the shell layout scheme was effectively obtained,verifying the correctness of the proposed method.

ASSESSMENT OF DAMAGE AND LIFE PREDICTION OF AUSTENITIC STAINLESS STEEL UNDERHIGH TEMPERATURE FATIGUE CREEP INTERACTION CONDITION

Itis understood that grain boundary cavitation is one of the detrimental processes for thedegradation of materials that reduces the creep fatigue life at high temperatures. Anewdamagefunction based on a modelforthecreep fatiguelife prediction in termsof nucleationand growth ofgrain boundarycavitiesisproposed. Thisdamagefunctionisacombination ofthetermsrelated to the cavitational damagein thelife prediction equation and is generallyapplicabletothe materialsin which failureis controlled by the grain boundary cavitationaldamage. Thecreep fatiguedatafrom thepresentandotherinvestigationsareusedtocheckthevalidityofthe proposed function, and itisshown thattheysatisfythereliability of damagefunction. Additionally, using this damage function, one may realize that allthe Coffin Manson plotsatthevariouslevelsoftensileholdtimeandtemperatureunderstrain controlled creep fatiguetestscan be normalizedto makethe mastercurve.

Measuring economic loss caused by ecological damages: a case study of China's forest ecosystem in 2005

At present about 60% of ecosystem has been damaged and degraded severely, resulting in enormous ecological loss globally. The essential cause is the irrational utilization of ecosystem by humankind, so it is tire key to changing improper environmental performance of humankind so as to prevent ecosystem from being damaged The quantitative valuation on the loss of ecological damage is an effective tool to guide human eco-environmental performance. In this paper, the concepts related to the valuation on ecological damage cost are introduced,＂ uncertainties that might arise in the valuation on the loss of ecological damage such as area coverage of valuation, ecological damage quantity, borders of ecological damage cost and data support are analyzed and the valuation approaches for the loss of ecological damage are also discussed As a case study, the economic losses of ecological damage of forest in 2005 in China are valuated.

Creep damage constitutive model of rock based on the mechanisms of crack-initiated damage and extended damage

Since the classical element model cannot describe the nonlinear characteristics of rock during the entire compressive creep process,nonlinear elements and creep damage are generally introduced in the model to resolve this issue.However,several previous studies have reckoned that creep damage in rock only occurs in the accelerated creep stage and is only described by the Weibull distribution.Nevertheless,the creep damage mechanism of rocks is still not clearly understood.In this study,a reasonable representation of the damage variables of solid materials is presented.Specifically,based on the Gurson damage model,the damage state functions reflecting the constant creep stage and accelerated creep stage of rock are established.Further,the one-dimensional and three-dimensional creep damage constitutive equations of rock are derived by modifying the Nishihara model.Finally,the creep-acoustic emission tests of phyllite under different confining pressures are conducted to examine the creep damage characteristics of phyllite.And the proposed constitutive model is verified by analyzing the results of creep tests performed on saturated phyllite.Overall,this study reveals the relationship between the creep characteristics of rocks and the corresponding damage evolution pattern,which bridges the gap between the traditional theory and the quantitative analysis of rock creep and its damage pattern.

Characterization of deep ground geothermal field in Jiahe Coal Mine

Research into the characteristics of geothermal fields is important for the control of heat damage in mines. Based on measured geothermal data of boreholes from 200 m to 1200 m in a Jiahe Coal Mine, we demonstrate non-linear but increasing relations of both geo-temperatures and geothermal gradients with increases depth. Numerically, we fitted the relationship between geo-temperatures and depth, a first-order exponential decay curve, formulated as: T(h) = 4.975 + 23.08 exp(h/1736.1).

Global climate damage in 2℃ and 1.5℃ scenarios based on BCC_SESM model in IAM framework

The quantitative functions for climate damages provide theoretical ground for the cost-benefit analysis in climate change economics,and they are also critical for linking climate module with economic module in the Integrated Assessment Models(IAMs).Nevertheless,it is necessary for IAMs to update sectoral climate impacts in order to catch up the advance in climate change studies.This study updates the sectoral climate damage function at global scale from climate Framework for Uncertainty,Negotiation and Distribution(FUND)model and develops the aggregate climate damage function in a bottom-up fashion.Besides conventional sectors such as agriculture,forestry,water resources,energy consumption and ecosystems,this study expands climate disaster types,assesses human health impacts caused by various air pollutants,and updates coastal damage by sea level rise.The Beijing Climate Center Simple Earth System Model(BCC_SESM)is used to project climate system based on Business-as-Usual(BAU)scenario,and the 2℃ and 1.5℃ scenarios based on RCPs and SSP2 databases.Sectoral results show that the agricultural sector is projected to suffer 63% of the total damage,followed by water resources(16%)and human health(12%)sectors in 2100.The regression results indicate that the aggregate climate damage function is in positive quadratic form for zero discounting.Under BAU scenario,the aggregate climate damage is projected to be 517.7 trillion USD during 2011-2100.Compared to that,the 2℃ and 1.5℃ scenarios are projected to respectively reduce climate damages by 215.6 trillion USD(approximately 41.6%)and 263.5 trillion USD(50.9%)in 2011-2100.

A Comparison of Two Approaches for Damage Evaluation on Optimal Mitigation and Adaptation Responses in China

Climate policies making are strongly impacted by the approach of damage evaluation.China is leading carbon dioxide(CO2)emissions in the world,and has agreed with Paris agreement to reduce CO2 emissions.China is also expected to be negatively impacted by climate change.One of main concerns is how to assess and monetize the climate damage from country-specific level.This paper builds a model comprising two approaches of damage evaluation and assesses China's mitigation and adapt at ion responses by 2100 for both of no policy and Paris agreemen t policy.Tt has the following findings:First,the emissions pathway and nonfossil fuel consumption share of total energy consumption differs slightly between the two approaches of damage evaluation.Second,with the Burkes approach,the climate damage avoided by adaptation is increasingly higher than that by mitigation when investment in adaptation starts to be massively injected with faster increasing trend by 2045.Third,climate expenses should be invested more to address higher level of the climate damage evaluated by the Burkes approach than by the Mannes approach.Fourth,the main findings in this paper are robust in terms of uncertain ties in the parame ters of damage function.