PermissibleWind Conditions for Optimal Dynamic Soaring with a Small Unmanned Aerial Vehicle

Dynamic soaring is a flight maneuver to exploit gradient wind field to extend endurance and traveling distance.Optimal trajectories for permissible wind conditions are generated for loitering dynamic soaring as well as for traveling patterns with a small unmanned aerial vehicle.The efficient direct collection approach based on the Runge-Kutta integrator is used to solve the optimization problem.The fast convergence of the optimization process leads to the potential for real-time applications.Based on the results of trajectory optimizations,the general permissible wind conditions which involve the allowable power law exponents and feasible reference wind strengths supporting dynamic soaring are proposed.Increasing the smallest allowable wingtip clearance to trade for robustness and safety of the vehicle system and improving the maximum traveling speed results in shrunken permissible domain of wind conditions for loitering and traveling dynamic soaring respectively.Sensitivity analyses of vehicle model parameters show that properly reducing the wingspan and increasing the maximum lift-to-drag ratio and the wing loading can enlarge the permissible domain.Permissible domains for different traveling directions show that the downwind dynamic soaring benefitting from the drift is more efficient than the upwind traveling pattern in terms of permissible domain size and net traveling speed.

An Ordering Policy for Deteriorating Items with Time-Dependent Quadratic Demand and Salvage Value under Permissible Delay in Payment

The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided.

Studies on permissible levels of breathing resistance for aircraft oxygen equipment（Review）

We have formulated 3 permissible levels of respiratory resistance for aircraft oxygen equipment in China based on a comprehensive analysis of the results of human pkysiological experiments and feasibility of technological design and performance with reference to existing standards and data. The ideal level can be used as a basic human physiological criterion. The applied permissible level is a criterion that must be followed in the process of design and production. The permissible level during maximum flow rate is presented as an extended allowable criterion for possible exceeding of the stable level for a short time.

An Inventory Model for Deteriorating Items under Conditionally Permissible Delay in Payments Depending on the Order Quantity

The purpose of this inventory model is to investigate the retailer’s optimal replenishment policy under permissible delay in payments. In this paper, we assume that the supplier would offer the retailer partially permissible delay in payments when the order quantity is smaller than a predetermined quantity (W). The most inventory systems are usually formed without considering the effect of deterioration of items which deteriorate continuously like fresh fruits, vegetables etc. Here we consider the loss due to deterioration. In real world situation, the demand of some items varies with change of seasons and occasions. So it is more significant if the loss of deterioration is time dependent. Considering all these facts, this inventory model has been developed to make more realistic and flexible marketing policy to the retailer, also establish the result by ANOVA analysis by treating different model parameters as factors.

Origin of Erosion and Hydraulic Problems of the San Roque Underground Arched Culvert Channel and Its Relationship with the Maximum Flow Rate and the Maximum Permissible Velocity

This work presents the hydrologic estimations of the hydraulic underground arched culvert channel (UACC) in Sabinal Basin, Chiapas, México and the hydrological problems associated with it, such as the erosion phenomenon and abrasion cavity formation in it. On the other hand, the maximum flows that the UACC could transport were analyzed, concluding that it no longer has the hydraulic capacity to transport the flow rate associated to return periods equal to or greater than five years and that maximum permissible velocity UACC’s bottom is 3 m/s.

Permissible Stress Level of Brick Masonry under Compressive Cyclic Loading

Laboratory tests revealed that the behavior of brick masonry under compressive cyclic loading is characterized by three distinct stress-strain curves. These three curves are termed as envelope curve, common point curve and stability point curve. The envelope curve is obtained by superimposing the cyclic peaks on the monotonic stress-strain curve. The common point curve is the locus of intersection points of loading and unloading curves of the cycles. If for the same cycle, the loading and unloading are repeated several times, the intersection points of loading and unloading paths will stabilize at a lower bound. The locus of these stabilized points （lower bound points） of all cycles form the stability point curve. Therefore, the stability point curve can be used as a measure for the allowable stress for masonry under cyclic loadings. The proposed cyclic allowable stress level is associated with the accumulation of residual （plastic） strain levels as a result of cyclic loading history. The permissible stress level was found to be about two thirds of the cyclic peak stress of the specimen.

The Legally Permissible Traditional Customary Uses of Wildlife and Forests under Kenyan Law

Kenya like most of sub-Saharan Africa is reliant predominantly on agriculture and natural resources;which include land, water, minerals and fisheries, but the most dominant of which are wildlife and forestry. Unlike minerals which are by law vested in the government and can only be extracted by it and not the citizenry, wildlife and forestry are resources that the citizens may utilize in their day to day lives to meet their needs. Apart from their consumptive uses, there are also non-consumptive uses and values of wild animals and forests;such as their intrinsic ecological value as gene banks, as well as their scenic value for viewing. These are essentially conventional values and uses. They are largely formal and universal ones that are universally obtaining across the world irrespective of the levels of civilization or cultural identity, and are even compatible with modernity. Apart from these, there are some wildlife and forestry uses which are unique to the typical African way of life as part of old traditional customs that have existed from earlier times. These are what are in this paper referred to as “traditional customary uses”. These uses are largely informal, rudimentary and archaic. They are nevertheless critical in the endemic African way of life and represent the inextricable rudimentary technologically bereft relationship between the African people and their natural resources. Under the country’s existing laws, some of these uses are prohibited and criminal sanctions prescribed to enforce their proscription, hence cannot be enjoyed or practiced. There are however others that the law has either expressly allowed, or not prohibited, hence may be lawfully enjoyed or practiced. These are what this paper has referred to as the legally permissible traditional customary uses;and are the ones that are its subject. As for wildlife, in the year 1977, the Kenya Government by a Legal Notice in the Kenya Gazette imposed a ban on all forms of hunting of wildlife. The ban is still in force. This therefore means that hunting is illegal, as legal prohibition has in effect prohibited all and any form of off-take or killing of wildlife. By implication therefore, under Kenyan law, only non-consumptive uses of wildlife may be enjoyed, and not the consumptive ones. These include viewing as well as socio-cultural and spiritual uses. In Kenya therefore, the only permissible traditional customary use of wildlife is its non-consumptive use for socio-cultural and spiritual purposes;subject of course to the existing legal prohibition on witchcraft under the Witchcraft Act (Cap 67 Laws of Kenya). This piece of legislation has prohibited the practice and promotion of witchcraft. This in effect means that the socio-cultural and spiritual uses of wildlife though legally permissible, will be enjoyed, provided it is not for witchcraft purposes. With regard to forests, this author has identified the following five as their legally permissible traditional customary uses under Kenyan law: Socio-cultural and spiritual (consumptive and non-consumptive) use, other than for witchcraft;use in herbal folk medicine, other than for witchcraft;use for human food and livestock fodder;use for firewood;and use as raw material in construction and traditional craft. Notably, in Kenya, traditional customary use is subject to the existing legal prohibition on witchcraft. Further, while it is the legally permissible use category that is the focus of this paper, the author nevertheless discusses the prohibited traditional customary uses as well. This paper is based on literature survey as well as data obtained from the author’s previous research whose primary data and findings have been published in recent times. It also draws from the documented research and diverse documented views of other commentators on the subject.

Permissible Minimum Thickness in Asymmetrical Cold Rolling

The minimum rolling thickness in asymmetrical rolling was analyzed compared with that in symmetrical rolling. The differential equilibrium equations on forces were established to calculate the asymmetrical rolling force equation by slab method. An implicit expression of the minimum rolling thickness was then derived from the rolling force equation and Hitehcock equation. The results show that permissible minimum rolling thickness of asymmetrical rolling only exists within a specific range of cross-shear ratio, which is termed the cross-shear zone proportion of the whole de- formation zone. Numerical computation was carried out to obtain a discrete solution of the minimum rolling thick- ness. Experiments were designed to investigate the influence factors on cross-shear ratio. Finally, experimental re- sults prove the correctness of the improved formula given.

A Note on a One-Parameter Weibull Distributed Deteriorating Item EOQ Inventory Model with Varying Quadratic Demand and Delay in Payments

In this paper, an EOQ inventory model is developed for deteriorating items with variable rates of deterioration and conditions of grace periods when demand is a quadratic function of time. The deterioration rate considered here is a special type of Weibull distribution deterioration rate, i.e., a one-parameter Weibull distribution deterioration rate and it increases with respect to time. The quadratic demand precisely depicts of the demand of seasonal items, fashion apparels, cosmetics, and newly launched essential commodities like android mobiles, laptops, automobiles etc., coming to the market. The model is divided into three policies according to the occurrence of the grace periods. Shortages, backlogging and complete backlogging cases are not allowed to occur in the model. The proposed model is well-explained with the help of a simple solution procedure. The three numerical examples are taken to illustrate the effectiveness of the EOQ inventory model along with sensitivity analysis.

Covalent Bond Based Android Malware Detection Using Permission and System Call Pairs

The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access information.Among the many smartphones available,those operating on the Android platform dominate,being the most widely used type.This widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent years.Therefore,there is an urgent need to develop new methods for detecting Android malware.The literature contains numerous works related to Android malware detection.As far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android applications.We introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious samples.This approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s behavior.We establish covalent bonds between permissions and system calls to assess their combined impact.We introduce a novel technique to determine these pairs’Covalent Bond Strength Score.Each pair is assigned two scores,one for malicious behavior and another for benign behavior.These scores serve as the basis for classifying applications as benign or malicious.By correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful actions.This comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the field.The results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature.

Android Permission机制的实现与安全分析

Permission机制作为Android安全的重要组成部分,受到了越来越多的关注,已有的研究主要集中在对应用程序申请的Permission进行静态分析上。文章从分析Permission机制的实现过程入手,分析了Permission机制自身的安全问题,发现了一个Permission机制漏洞。应用程序利用该漏洞可以绕过权限管理,主动提升应用程序的访问权限,为后续攻击提供支持。同时文章也对Permission机制其它方面的安全特性进行了分析。

POLLUTION TREND IN THE TUMEN RIVER AND ITS INFLUENCE ON REGIONAL DEVELOPMENT

The Tumen River had failed to meet Grade Ⅲ and Ⅳ levels in the environmental quality standard for surface water, and had exceeded Grade Ⅴ level. Surface water pollution is serious. The major excessive standard pollutants were COD Mn and SS. After taking effective treatment steps, the worsening trend of water pollution will be basically under control. But the change of runoff in the Tumen River is large in a year, especially during as long as five month freezing period, smaller flow and lower temperature of river waters led to weak dilution and self purification capacity. The water quality of the Tumen River will not reach the appoint functional water quality standards, even if sewage meets discharge standard, which will influence water resources utilization in the lower reaches of the Tumen River and regional economic development. Therefore water pollution has become the major restrictive factor of the development of the Tumen River area.

一种增强的Android安全机制模型

随着Android系统的日益流行,其安全问题受到了越来越多的关注。尽管Android Permission机制能在一定程度上保证安全性,但在实际应用中却缺乏灵活性,基于此提出了一种与Apex相兼容的策略模型。该方法主要针对Apex的安装程序包Poly。在Ploy安装程序之前先对应用程序和权限进行分析检测,然后将检测分析后的权限呈现给用户。实验结果表明在造成一定性能损失的情况下,新的框架可以有效减少用户所需设置的权限。

Irrigation erosion of irrigated soils in the foothills of southern Kazakhstan

Abstract： This paper presented the results from the study of irrigation erosion of irrigated lands in southern Ka- zakhstan. The main purpose of the work is the conservation of the fertility of irrigated soils, and then the soils of the upper, middle and lower sections of the slopes at the experimental site were studied. Based on field investigations, authors studied the water resistance of aggregates of gray-brown soils and light gray soils before and after irrigation and qualitative indicators of changes in physical and chemical properties of structured soils in irrigation were de- termined by conventional methods of soil research. The results indicated that the changes in the physical properties of soils by using polymeric compounds created a fundamentally new opportunity to control water erosion of soils.

Defluoridation of Water by a Biomass: <i>Tinospora cordifolia</i>

This research is focused on the search of a biomass for the sequestration of fluoride from drinking water. Defluoridation of water was studied by batch experiments in biosorption process. The biomass was found to reduce fluoride to permissible limit 1.5 mg/L as prescribed by WHO. The efficiency of the sorption process was investigated under different experimental parameters such as pH 7, standing time 120 min and biomass doses 7.0 g with 5 mg/L concentration of fluoride. Neutral pH was identified as the optimum condition of the medium and 120 minutes was the best contact time for maximum fluoride adsorption. The experimental data was found good fitting to Langmuir and Freundlich isotherm models. In interference study tolerable effect was found with 50 mg/L concentration of co-ions, whereas increasing the concentration of co-ions retarded the fluoride removal capacity in some extent. FT-IR spectrum analysis showed fluoride binding in the different frequency ranges of the biomass. Eventually, this plant biomass is recommended as a suitable and low cost adsorbent to reduce fluoride into standard permissible limit.

Android操作系统的安全机制研究

Android系统自推出以来，就以明显的优势逐渐扩大市场占有份额。Android是一个开放性的系统，备受开发者的青睐，其安全性至关重要。研究了Android系统的用户ID机制、应用程序签名机制、沙箱隔离机制等安全策略，分析了它在硬件方面、Linux内核方面及Android自身权限机制方面存在的安全隐患。

浅谈司法公证材料的英译

司法公证翻译因关系到当事人在境内外的权利和义务而应格外严谨准确。笔者近年来受有关部门及当事人的委托承担了部分公证材料的翻译,从各国签证官和国外机构获得了大量有益的信息反馈,现不揣冒昧从文体特征。

The Impact of Some Uncontrolled Landfill Sites on the Ecosystems of Surrounding Areas of Eastern and Western Parts of Georgia

The most visible uncontrolled landfill sites were selected in the western and eastern parts of the territory of Georgia. Particularly, in eastern Georgia the regions of Mtskheta-Mtianeti and Kvemo Kartli have been researched;and in western Georgia Imereti and Samtskhe-Javakheti correspondingly. Both chemical and microbiological analyses were conducted in the samples taken from their adjacent territories. In case the landfill site is located near the river, during field works using portable equipment main physical-chemical indicators of surface waters were determined. After processing of the obtained results the corresponding estimations were provided. The risks due to the environmental pollution and negative impacts on population health were assessed.

Optimization of geothermal water exploitation in Xinji,Hebei Province,P.R.China

Geothermal with features of large reserves and non-pollution has been one of the most important energy. China has significant geothermal resources. There are rich hydrothermal resources in Xinji, which has been in development for 5 years. However, hot water continues to decrease because of extensive exploitation and utilization. We selected exploration area as study area, build a set of numerical models of Guantao formation on the basis of actual geological conditions. We get the distribution of hydraulic conductivity from 1.7 m/d to 1.9 m/d by parameter inversion using historical water level monitoring data, and simulation effect is good. We calculate the maximum permissible exploitation under the limitation of 200 m in depth in 50 years which is about 2.2 million m3/a. The results will provide theoretic support for plan making of geothermal exploitation.

Data Mining and Machine Learning Methods Applied to A Numerical Clinching Model

Numerical mechanical models used for design of structures and processes are very complex and high-dimensionally parametrised.The understanding of the model characteristics is of interest for engineering tasks and subsequently for an efficient design.Multiple analysis methods are known and available to gain insight into existing models.In this contribution,selected methods from various fields are applied to a real world mechanical engineering example of a currently developed clinching process.The selection of introduced methods comprises techniques of machine learning and data mining,in which the utilization is aiming at a decreased numerical effort.The methods of choice are basically discussed and references are given as well as challenges in the context of meta-modelling and sensitivities are shown.An incremental knowledge gain is provided by a step-bystep application of the numerical methods,whereas resulting consequences for further applications are highlighted.Furthermore,a visualisation method aiming at an easy design guideline is proposed.These visual decision maps incorporate the uncertainty coming from the reduction of dimensionality and can be applied in early stage of design.