Pumping Relief Chinese-built water project is a game-changer for local communities in Tanzanian town

When Monica Jiwani relocated to Arusha,the third-largest city in Tanzania,she was dreaming of a happy life in a scenic area.Instead,she was immediately confronted with a harsh and painful reality-scarcity of clean water.The thought of using contaminated water became a constant source of headache.

西藏交通警察道路执法工作的风险与防范

西藏自治区自然、地理与气候环境复杂且特殊,道路交通环境相对恶劣,这导致当地交通警察道路执法工作面临诸多风险,包括警员人身安全和执法效能等风险。对此,文章对西藏交通警察道路执法工作风险进行了调查分析,从地区环境、警员安全意识与技能、执法装备、社会宣传和教育等角度探讨了相关风险的成因,针对性相关风险成因,提出从优化警力配置与道路信息推送、加强警员培训、完善警务装备、加强法治化宣传教育等工作来消除相关风险,以期保障警员安全并改善西藏交通环境。

考虑海洋环境-船体-螺旋桨-主机之间的动态相互作用的船舶在实海况下的油耗预报

The fuel consumption of a ship has always been an important research topic,but nowadays its importance has even increased as it is directly related to a ship’s greenhouse gas(GHG)emissions,which is now tightly regulated.In this paper,such a dynamic model is presented.The ship’s resistance in calm water and propeller’s performance in open water are required as input.The hull efficiency is estimated empirically.The diesel engine is modelled by a first-order transfer function with a delayed response and its performance is calibrated with the data from the manufacturer’s catalogue.A governor is applied to maintain the pre-set engine’s rotational speed and to control the engine fuel rate.A slope limiter is employed to approximate the actual engine operation during engine transients.The default values can be obtained from the manufacturer engine load acceptance diagram.The developed model is implemented in MATLAB SIMULINK environment.After validation against third-party published results,the influence of using different types of governors on ship speed and fuel consumption is investigated.The model is also applied to simulate the fuel consumption of a ship during a typical acceleration manoeuvre and the scenario of a real ship encountering harsh weather conditions.

Scientists Develop Magnetic- Acoustic Actuated CAR-T Cell Robots for Precision Antitumor Immunotherapy

Although chimeric antigen receptor(CAR)T cell therapy has shown incredible success in treating hematological malignancies,its application in solid tumors is unsatisfactory owing to the harsh physical barriers and immunosuppressive microenvironment.The ideal CAR T therapy will require a novel armored CAR T cell engineered to navigate the circulatory system,penetrate tumor tissues,and survive in the harsh tumor microenvironment to exert an adequate immune effect.

车内噪声主动控制发展综述及其在实车上的应用

本文对小型轿车车内噪声分布及其声源进行了分析,对国内外研究者对噪声主动控制研究成果的发展历程作了综述,并介绍了噪声主动控制理论及模型,最后结合具体实车,介绍了目前应用在实车上的车内噪声主动控制范例。

Systematical Development of NVH Engineering for Vehicle Electrical Powertrain Based on an Optimized V-Model

For systematical NVH development of vehicle (especially for mass-production passenger vehicles) electric powertrain, an optimized V-Model is designed and has been implemented in the entire component-vehicle development, which integrates three individual branches: simulation, validation and optimization. Compared to the V-models in the traditional sense, this optimized V-model is not only driven by requirement and task accomplishment but also maximum optimization of NVH system performance. In this case, developing procedures are capable to be efficiently iterated and the NVH engineering can be expanded into 3D with this V-model.

A Track Initiation Method for the Underwater Target Tracking Environment

A novel efficient track initiation method is proposed for the harsh underwater target tracking environment(heavy clutter and large measurement errors): track splitting, evaluating, pruning and merging method(TSEPM). Track initiation demands that the method should determine the existence and initial state of a target quickly and correctly.Heavy clutter and large measurement errors certainly pose additional difficulties and challenges, which deteriorate and complicate the track initiation in the harsh underwater target tracking environment. There are three primary shortcomings for the current track initiation methods to initialize a target:(a) they cannot eliminate the turbulences of clutter effectively;(b) there may be a high false alarm probability and low detection probability of a track;(c) they cannot estimate the initial state for a new confirmed track correctly. Based on the multiple hypotheses tracking principle and modified logic-based track initiation method, in order to increase the detection probability of a track,track splitting creates a large number of tracks which include the true track originated from the target. And in order to decrease the false alarm probability, based on the evaluation mechanism, track pruning and track merging are proposed to reduce the false tracks. TSEPM method can deal with the track initiation problems derived from heavy clutter and large measurement errors, determine the target’s existence and estimate its initial state with the least squares method. What’s more, our method is fully automatic and does not require any kind manual input for initializing and tuning any parameter. Simulation results indicate that our new method improves significantly the performance of the track initiation in the harsh underwater target tracking environment.

Smart Manipulation of Gas Bubbles in Harsh Environments Via a Fluorinert-Infused Shape-Gradient Slippery Surface

Fundamental research and practical applications have examined the manipulation of gas bubbles on open surfaces in lowsurface-tension,high-pressure,and high-acidity,-alkalinity,or-salinity environments.However,to the best of our knowledge,effi cient and general approaches to achieve the smart manipulation of gas bubbles in these harsh environments are limited.Herein,a Fluorinert-infused shape-gradient slippery surface(FSSS)that could eff ectively regulate the behavior of gas bubbles in harsh environments was successfully fabricated.The unique capability of FSSS was mainly attributed to the properties of Fluorinert,which include chemical inertness and incompressibility.The shape-gradient morphology of FSSS could induce asymmetric driving forces to move gas bubbles directionally on open surfaces.Factors infl uencing gas bubble transport on FSSS,such as the apex angle of the slippery surface and the surface tension of the aqueous environment,were carefully investigated,and large apex angles were found to result in large initial transport velocities and short transport distances.Lowering the surface tension of the aqueous environment is unfavorable to bubble transport.Nevertheless,FSSS could transport gas bubbles in aqueous environments with surface tensions as low as 28.5±0.1 mN/m,which is lower than that of many organic solvents(e.g.,formamide,ethylene glycol,and dimethylformamide).In addition,FSSS could also realize the facile manipulation of gas bubbles in various aqueous environments,e.g.,high pressure(~6.8 atm),high acidity(1 mol/L H 2 SO 4),high alkalinity(1 mol/L NaOH),and high salinity(1 mol/L NaCl).The current fi ndings provide a source of knowledge and inspiration for studies on bubble-related interfacial phenomena and contribute to scientifi c and technological developments for controllable bubble manipulation in harsh environments.

Boosting lithium batteries under harsh operating conditions by a resilient ionogel with liquid-like ionic conductivity

New chemistries are being developed to increase the capacity and power of rechargeable batteries. However, the risk of safety issues increases when high-energy batteries using highly active materials encounter harsh operating conditions. Here we report on the synthesis of a unique ionogel electrolyte for abuse-tolerant lithium batteries. A hierarchically architected silica/polymer scaffold is designed and fabricated through a facile soft chemistry route, which is competent to confine ionic liquids with superior uptake ability (92.4 wt%). The monolithic ionogel exhibits high conductivity and thermal/mechanical stability, featuring high-temperature elastic modulus and dendrite-free lithium cycling. The Li/LiFePO_(4) pouch cells achieve outstanding cyclability at different temperatures up to 150 ℃, and can sustain cutting, crumpling, and even coupled thermal–mechanical abuses. Moreover, the solid-state lithium batteries with LiNi_(0.60)Co_(0.20)Mn_(0.20)O_(2), LiNi_(0.80)Co_(0.15)Al_(0.05)O_(2), and Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2) cathodes demonstrate excellent cycle performances at 60 ℃. These results indicate that the resilient and high-conductivity ionogel electrolyte is promising to realize high-performance lithium batteries with high energy density and safety.

Surface Roughness Modification of Free Standing Single Crystal Silicon Microstructures Using KrF Excimer Laser Treatment for Mechanical Performance Improvement

Single crystal silicon freestanding structures for tensile and fatigue testing were treated with KrF excimer laser to improve surface roughness and accordingly mechanical performance. Sample thickness was 5 μm. Localized laser treatment was successful in eliminating the scallops developed during Bosch process and in reducing surface roughness. Harsh irradiation at laser energies up to 4 J/cm2 was only possible due to localized treatment without significant vibrations occurring on the freestanding samples that led to fracture in preliminary experiments at energies as low as 0.16 J/cm2. Finite element analysis was used to investigate the temperature distribution on the irradiated structures. Atomic force microscopy (AFM) and Raman spectroscopy were also used to assess surface roughness, crystallinity changes and surface stresses developing on surfaces subjected to perpendicular laser irradiation. At a high energy (3.2 J/cm2) the top surface showed a decrease of roughness compared to fabricated samples. Raman spectroscopy showed the dominance of crystalline silicon after laser irradiation. The effects of laser energy, number of

Influence of volcanic activity on vegetation succession and growth environment on the hillslope of Sakurajima Volcano in southern Kyushu,Japan

This study was conducted in order to examine the influence of long-term volcanic activity on vegetative succession and growth on the slope of Sakurajima in southern Kyushu, Japan. We investigated the vegetation,depth of the volcanic ash layer, and dry density and p H of the surface soil at six places on the north-northwestern slope, 2.3–3.4 km from the Minami-dake crater, where a layer of pumice stone was deposited by the Taisho eruption in 1914. The height and diameter at breast height（DBH） of the trees increased with increasing distance from the Minami-dake crater, as did the number of individuals and species, and basal area. The Shannon–Wiener diversity index（H＇） demonstrates that vegetative succession is significantly affected by distance from the Minami-dake crater, as areas farther from the crater exhibited later seral stages. Comparison of the diversity index and species number of the crater region with that of the climax forest in Kagoshima indicates that vegetative growth alone cannot advance succession in the study area, as the local vegetative community is heavily influenced by the harsh environmental conditions associated with continual exposure to long-term volcanic activity. Seral stage, ash layer depth,dry density, and p H of the soil surface layer are governed by distance from the Minami-dake crater. The results of this study indicate that conditions for vegetative growth and succession improve with increasing distance from the source of constant volcanic activity. Thus, soil development is promoted by the acidification of the soil, which decreases the dry density and p H of the soil surface layer.The introduction of plant species resistant to volcanic ash and gas is recommended to promote soil development and improve the infiltration capacity of the soil.

Wireless Network Requirements and Solutions for the Future Circular Collider:A Hostile Indoor Environment

The European organization for nuclear research(CERN)is planning a high performance particle collider by 2050,which will update the currently used Large Hadron Collider(LHC).The design of the new experiment facility includes the definition of a suitable communication infrastructure to support the future needs of scientists.The huge amount of data collected by the measurement devices call for a data rate of at least 1 Gb/s per node,while the need of timely control of instruments requires a low latency of the order of 0.01μs.Moreover,the main tunnel will be 100 km long,and will need appropriate coverage for voice and data traffic,in a special underground environment subject also to strong radiations.Reliable voice,data and video transmission in a tunnel of this length is necessary to ensure timely and localized intervention,reducing access time.In addition,using wireless communication for voice,control and data acquisition of accelerator technical systems could lead to a significant reduction in cabling costs,installation times and maintenance efforts.The communication infrastructure of the Future Circular Collider(FCC)tunnel must be able to circumvent the problems of radioactivity,omnipresent in the tunnel.Current technologies transceivers cannot transmit in such a severely radioactive environment.This is due to the immediate destruction of any active or passive equipment by radioactivity.The scope of this paper is to determine the feasibility of robust wireless transmission in an underground radioactive tunnel environment.The network infrastructure design to meet the demand will be introduced,and the performance of different wireless technologies will be evaluated.

Heat Management System for Long-term Continuous Observation of Electronic Instrumentation in Deep Earth

Deep penetration into the Earth’s interior and direct monitoring of weak changes in physical fields and their cumulative processes and effects in the deep Earth can enhance the identification of deep Earth targets and deepen the degree of knowledge of the details of the deep Earth structure and deep processes(Moskvitch,2014),which is important for promoting the development of Earth system science.

欧·亨利的《警察与赞美诗》

《警察与赞美诗》(The Cop and the Anthem)是欧·亨利的优秀短篇小说之一,反映了现实的悲惨,提出了尖锐的问题。这个短篇写的是一个流浪汉,衣食无着,想去监狱度过寒冬,有意犯法,警察却不去抓他。但他听了赞美诗,深受感动,决心忏悔过去。

Late for work迟到

Tucked up warm and fast asleep,Wandering in the land of dreams.While the daylight, filtering through,Says good-bye to moonlight beams.

Vehicle Dynamics with Additional Entry Lane of a Roundabout

This research is dedicated to the study of dynamics of vehicles moving through the additional entry lanes of a roundabout. Using the data created on the base of that model the constant coefficients of the sixth-degree polynomial function, previously proposed by us, have been found. In result of this there were obtained two analytic equations of vehicles’ movement, where one of them presented with the positive sign of the leading coefficient and the other one negative. These two equations allowed to make comprehensive investigation of the delays and the kinematics of the vehicles moving by such kinds of lanes. Based on the appropriate calculations it is determined vehicles’ consequent delays, velocities, accelerations and decelerations. Analyzing the delays, the dynamics of accelerations and decelerations, it is done an assumption that if the leading coefficient of algorithm of movement of vehicles is negative than it will lead to larger deceleration and consequently higher environmental pollutions and higher noises.

Can Sense of Coherence Indicate Resilience and Mitigate the Cycle of Violence in Parenting?

Background: Harsh parenting practices during childhood have long-term negative effects on children’s mental health. A focus of nursing care on women’s resilience should be implemented because mothers who have experienced violence tend to be harsh parents. Aim: This study investigated the association between mothers’ violent experiences and harsh parenting (HP) and examined the effects of a sense of coherence (SOC) on this association, assuming that SOC can be an indicator of resilience. Method: In this prospective cohort study of 487 mothers, data were collected on SOC and history of intimate partner violence (IPV) at 1 year after childbirth and HP of their child at 18 months after childbirth. Results: In the 277 responses analyzed by multiple logistic regression analysis, a strong SOC moderating the effect on HP was observed for current IPV and witnessing IPV in childhood, but not for experiencing childhood corporal punishment. Discussion: SOC is a useful indicator of resilience in female victims of violence and is effective in regulating stress spillover. However, its effects are weakened by the learned acquisition aspect of violence. Conclusion: In nursing, providing support to alleviate stress and relearn parenting based on an assessment of the mother’s history of violence and SOC as the resilience indicator is important in curbing HP.

SYMBOLS IN THE SCARLET LETTER

Plot Summary of The Scarlet Letter: The Scarlet Letter has as its setting Puritan Boston during the mid-17th century.Young Hester Prynne,a“fallen woman”,is sentenced towear a scarlet A,signifying“adultery,”because she has a lover whenher aged husband is not with her.Consequently she is driven out of theordinary relations with humanity,and is thus able to view critically thevarious aspects of the society.Hester is not overwhelmed by the

Seismic Evaluation of Reinforced Concrete Frames in the Harsh Environment Using Pushover Analysis

The main objective of this paper is to evaluate the seismic response of buildings of typical reinforced concrete frames when concrete starts to deteriorate gradually and to make a comparison between the base shear and the displacement at different stages of earthquake loading. Typical 5, 15, 20 and 30-storey reinforced concrete frames have been designed for seismicity according to the recently adopted seismic code in Abu Dhabi, ACI 318-08/IBC 2009 code. A pushover analysis has been performed to these four buildings by using SAP 2000. Twenty-four models have been created (6 models for each building) by decreasing the concrete strength gradually from 4000 psi (281 kg/cm2) to 1500 psi (105 kg/cm2). This is to simulate the effect of harsh environment on the strength of concrete in existing buildings.