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In modern fulfillment warehouses, agents traverse the map to complete endless tasks that arrive on the fly, which is formulated as a lifelong Multi-Agent Path Finding (lifelong MAPF) problem. The goal of tackling this challenging problem is to find the path for each agent in a finite runtime while maximizing the throughput. However, existing methods encounter exponential growth of runtime and undesirable phenomena of deadlocks and rerouting as the map size or agent density grows. To address these challenges in lifelong MAPF, we explore the idea of highways mainly studied for one-shot MAPF (i.e., finding paths at once beforehand), which reduces the complexity of the problem by encouraging agents to move in the same direction. We utilize two methods to incorporate the highway idea into the lifelong MAPF framework and discuss the properties that minimize the existing problems of deadlocks and rerouting. The experimental results demonstrate that the runtime is considerably reduced and the decay of throughput is gradually insignificant as the map size enlarges under the settings of the highway. Furthermore, when the density of agents increases, the phenomena of deadlocks and rerouting are significantly reduced by leveraging the highway.

Background We aimed to estimate the stage-specific impact of lymph node dissection (LND) on survival for upper urinary tract urothelial carcinoma (UTUC) patients treated with nephroureterectomy (NU). Methods Overall, 7278 UTUC patients undergoing NU within the SEER database from 2004 to 2015 were identified. Kaplan-Meier plots illustrated overall survival (OS) and cancer-specific survival (CSS) rates according to LND status. Multivariable Cox regression analyses assessed the effect of LND on OS and CSS rates stratified by pathological tumor stage. Results LND was performed in 26.9% of patients, and in 18.6, 23.3, 31.2 and 45.9% for pT1, pT2, pT3 and pT4 patients, respectively (P P P > 0.05). LND with 1 to 3 regional lymph nodes removed was prone to a higher OS or CSS only in pT4 compared to no LND (both P P Conclusions The beneficial effect of LND especially LND with 4 or more regional lymph nodes removed on survival was evident in pT3/4 patients. LND can be considered for pT3 and pT4, for pT1/2 remains to be seen, both of which will be verified by further prospective studies.

For the development trend of advanced aircraft wind tunnel tests which require shorter cycle time and lower cost, a new wind tunnel testing process called Modern Design of Experiments (MDOE) is under development at NASA Langley Research Center. This paper presents a case study of application of Modern Design of Experiment methods in high speed wind tunnel tests based on the aerodynamic data of certain type of aircrafts. The full process including experiment design, execution, analysis of variance, and block design is described. Comparisons between MDOE predictions and OFAT measurements were made in the present study. The results show that the MDOE methods have well predictive capability to meet specific test objectives with less data volume, less cost and less time compared to the conventional OFAT methods, which means the MDOE approach established and used in this study is feasible enough to meet specific aerodynamic wind tunnel testing objectives in place of conventional OFAT methods.

Nickel base multi-component alloy Ni-PNi-Cu-PNi-W-P and Ni-Co-P were prepared using electroless plating methodand examined by scanning electronic microscope, x-ray diffractometer and x-ray flourometer respectively on its morphology, component and structure characteristic. Thermodynamic stability of the three samples were also examined by thermal analysis method. Research revealed all three coatings possessed compact and tight surface structure with excellent thermodynamic stability. Also, it was more efficient to enhance the thermodynamic stability of the Ni-P alloy coating by adding atom Cu rather than atom Co or atom W. While Ni-W-P coating demonstrated a microcrystalline structure, both Ni-Co-P and Ni-Cu-P were amorphously structured. After thermal treatment three alloy coatings all experienced transformation from non-crystalline or microcrystalline state to a more stable crystalline state, XDR analysis indicated the reaction products were unit cells and inter metallic compounds of Ni3P.

Based on copper foil, this paper takes electrodeposition to prepare tin-nickel alloy based anode material, which is of Sn 81.23% (Mass Fraction, the same as below), and Ni 18.77% (Mass Fraction, the same as below). It also studies the plating state, and plating structures and its electrochemical properties under heat treatment at different temperatures. The X-ray diffraction analysis (XRD) shows that the plating structures are all Ni3Sn4 and unalloyed individual-phase Sn under plating state and 200 oC heat treatment, and are Ni3Sn2 , Sn, Ni3Sn2 , Ni3Sn4 under 300 oC and 450 oC heat treatment respectively. In a button cell, which was made up with lithium slice, the results of charge-discharge cycle test and cyclic voltammetric curves test indicate that tin-nickel alloy’s specific capacity and charge-discharge cycle performance are related to the heat treatment temperature and structure of lithium battery anode material. The plating under plating state and 200oC heat treatment has high specific capacity, and its charge-discharge stability is well above that of the plating under other temperatures. Under 200 oC heat treatment, the plating could crystallize better and increase its content of Ni3Sn4. Its charge-discharge stability would be well above that of the original plating state. The scanning electron microscope (SEM) shows that before discharging, the plating of tin-nickel alloy was made up of small spherical particles, which are uniform and dense. The plating began to swell and crack after 50 times charge-discharge, which may lead to rapidly attenuate the plating’s specific charging capacity.

The present study measures the nutritional status and the blood pressure to assess their relationship in a group of children and adolescents in the Hainan province, China. A total of 5,456 students aged 7 to 18 years were recruited from 10 public schools in Hainan province of South China during the period March 2009 to December 2009. Height, weight, systolic blood pressure, and diastolic blood pressure were measured by health-care professionals. Body mass index (BMI) was calculated and used to define thinness, overweight, and obesity according to the existing standards. Prevalence of thinness, overweight, obesity, pre-hypertension, and hypertension was computed, and logistical regression model was used to examine the association of BMI with elevated blood pressure. A high prevalence of thinness was observed in male and female children and adolescents (34.0% and 34.3%, respectively). The percentage of overweight and obesity was 2.7% and 1.3%, respectively. Pre-hypertension and hypertension were detected in 3.9% and 3.3% children and adolescents, respectively. Multivariate logistical regression analysis showed that obesity was positively associated with both pre-hypertension and hypertension, with adjusted odds ratio of 1.44 (95% confidence interval (CI) = 1.08–1.92, P = 0.014) and 2.00 (95%CI = 1.53–2.60, P

The purpose of this study was to research the effect of tin-nickel alloy plating solution temperature, the dosage of graphite powder on the structure and composition of tin-nickel –graphite composite materials prepared by electrodeposition, discuss the relationship between carbon content and the specific capacity composite plating, charge and discharge efficiency, cyclic reversibility. The results show: control the tin-nickel alloy plating solution at 55-60°C, dosage of graphite powder below 10g.L-1 , [Sn2+]/[Ni2+]=1.7, then by electodeposition, a tin-nickel–graphite composite plating with about 80% of tin content ( mass fraction, similarly hereinafter) and carbon content below 7.82% can be obtained. The SEM shows that the composite plating is consist of small spherical particles forming network structure, with status of porous clusters. The charge/discharge cycle testing and cyclic voltammetry testing of the button cell composed of composite anode and lithium slices indicate: when the carbon content in composite plating increases, the specific capacity, charge/discharge efficiency and cyclic reversibility are obviously increased. When the carbon content reaches to 7.82%, the initial specific capacity is 1034.4mAh•g-1 , after 13 cycles, the specific capacity is 603.4mAh•g-1 , after 50 cycles, the specific capacity is 218.3mAh•g-1. The specific porous structure of composite plating and a good charge/discharge performance of graphite powder improve the electrochemical properties of composite anode materials.

By electron energy spectrometer,X-ray diffractometer,transmission elec-tron microscopy andmicro-hardometer,the depositing speed of electrolessNi-Co-P plating baths,chemical composition,crystal structure and microhardness of the alloy coatings were inspected and analyzed with ultrasonic and rare earth metalcerium intervening in electroless Ni-Co-P plating•The results show that the depositing speed of electroless Ni-Co-P plating isobviously increased under the effect of ultrasonic.The chemical compositions of electroless Ni-Co-P plating are changed，The XRD of coating has a diffuse sexual diffraction peak closing to typical amorphous structure.the obtained Ni-Co-P coating has more fine crystal grain, even and dense surface morphology. Its wear resistance and hardness have been improved obviously.

The action mechanism of ultrasonic was investigated when the ultrasonic wave as a new kind of energy importation way was introduced in the technology of electroless plating at low temperature. Compared with common electroless plating coatings, influence factors of improving the properties of the Ni-Cu-P Alloy coating under ultrasonic were analyzed through hardness, dense nitric acid spot testing metallographic structure observation and EDS. Experimental results show that, under the effect of ultrasonic, the obtained Ni-Cu-P coating has more fine crystal grain, even and dense surface morphology. Its corrosion resistance and hardness have been improved obviously.

In order to obtain stable and homogeneous diamond-Ni-P composite electroless plating, dispersants were selected by determining the height of emulsion in the colorimetric cylinder after standing different time.The structure,elemental contents and properties of the diamond-Ni-P composite electroless plating coating were investigated by SEM and EDS. Experimental results show that OP-10 of 50mL•L-1 and softex kw of 1g•L-1 have better dispersing effect to diamond powder of 1g•L-1 in water. This composite electroless plating solution can keep stable for more than twelve or eight hours respectively at 85°C. While in the electroless plating solution, Softex kw of 1g•L-1 has better dispersing effect and can be stable for more than two hours at 85°C. The diamond powder grains in the composite coating are homogeneous and the content of carbon is 2.261 wt% under the certain amount of the selected dispersant. When the content of diamond was 5g•L-1 in the solution, the diamond powders were dispersed non-homogeneously in plating and cluster phenomena were appeared. The composite electroless plating coating consists of amorphous Ni-P and diamond powder. Its hardness and porosity are similar to those of the electroless plating Ni-P coating. The wear-resisting is improved greatly,which is 2.6 times of electroless plating Ni-P or 2 times of that after heat treatment at 400°C for one hour.

To improve the performances of LiFePO4, a positive material in lithium battery, research on the influence of doping amount and doping form of carbon nanotubes (CNTS) on electrical resistivity, specific capacity, specific surface area and particle size distribution of LiFePO4 powder was conducted. The results indicated that, addition of CNTS significantly reduced the electrical resistivity no matter in pure LiFePO4 or LiFe0.98Mg0.02PO4; with same usage, coating of CNTS as carbon source performed better than mechanical grinding and mixing with LiFePO4. With the increase of CNTS content, a rising trend of both specific surface area (BET) and particle size (D50) in LiFePO4 powder was observed, but seeing a slight drop in discharge capacity under the rates of 0.2C and 0.5C. When the content of CNTS reached 3% (by mass) respectively through mechanical mixing and being added as carbon source, electrical resistivity of pure LiFePO4 dropped from over 105Ω•cm to 1868Ω•cm and 27Ω•cm accordingly, and that of LiFe0.98Mg0.02PO4 dropped from over 105Ω•cm to 4800Ω•cm.

Dispersants are selected and optimized by determining the height of emulsion in the colorimetric cylinder after standing in order to ensure the homogeneity of the powder and the stability of electroless plating solution. Experimental results show that non-ionic surfactants such as PEG6000,PEG10000,OP-10 have stronger emulsifying ability to α-Al2O3 powder in ordinary condition and IW has more stability at 80~90°C. The optimum conditions are suggested as PEG6000 8g, IW 0.95g and ethanol 3mL per 50mL solution. Moreover, this composite electrolessplating solution is stable for seven days under 90°C. Therefore it has more dispersing ability. The SEM images show that the powder in the coating is homogeneous. The electroless plating coating consists of α-Al2O3 and amorphous Ni-P that will change into crystal Ni3P and Ni-base solid solution after heat treatment at 400°C for one hour, the α-Al2O3 powders are dispersed evenly in the nickel matrix.

The crystallization behaviors and microstructural developments in the CaO-MgO- Al2O3-SiO2 glass with Fe2O3, ZrO2 and F as additives were investigated by using scanning electron microscopy, X-ray diffraction and differential scanning calorimetry techniques. In the glass sample with 1.0wt% Fe2O3, only surface crystallization were observed, in which a three-layer compound surface containing the fine dendrite, finer fibrous morphology and particle-shaped crystals was formed respectively from the near free surface to the inner region. The crystalline phases precipitated were anorthite and wollastonite at 1000°C, and diopside at 1040°C. The addition of ZrO2 suppressed the nucleation and growth of the crystalline phases. The addition of another 4.0wt% fluorine into the glass with a pair of 1.0wt% Fe2O3 and 2.0wt% ZrO2 induced the bulk crystallization, the surface and bulk crystallizations were both observed at 1040°C. At the surface, a three-layer morphology, which had similar morphology to the glass with 1.0wt% Fe2O3 was formed. In the bulk region, the block-shaped crystalline phases were precipitated homogeneously in the residual glass.

We investigate the nonlinear correlations of protein sequences by using the nonlinear prediction method developed in nonlinear dynamical theory. It is found that a lot of protein sequences show strong nonlinear correlations and have deterministic structures. Further investigations show that the strong nonlinear correlations of these protein sequences are due to the symmetries of their tertiary structures. Furthermore, the correlation lengths of the sequences are related to the degrees of the symmetries. These results support the duplication mechanism of protein evolution and also reveal one aspect how amino acid sequences encode their spatial structures.

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: 1. Aortic intramural hematoma (IMH) is an important component of acute aortic syndrome. A crescent-shaped area along the aorta wall with higher attenuation than that of blood on the noncontrast CT scan No contrast enhancement effect within the area...

Fixed field experimental studies are carried out on daily variations of the undisturbed community and soil respiration fluxes in different phenological phases of 2001―2002 in semiarid Aneurolepidium chinense steppe of Inner Mongolia, China using static black chamber method. Corresponding statistical analysis of the contributions of the water-heat factors (air temperature, ground temperature, surface soil water content) and ecological factors (aboveground biomass, underground biomass, litter biomass) to daily variation law of the undisturbed community and soil respiration fluxes as well as differences in daily respiration are also conducted. The results indicate that undisturbed community and soil respiration have apparent daily variation laws, daily variation patterns of respiration fluxes during different phenological phases are basically the same, and the variations of environmental factors only exert effect on CO 2 emission intensities, while the effect on daily variation pattern of grassland CO 2 emission fluxes is relatively small. The daily total respiration of the undisturbed community in different phenological phases ranges from 1.34―10.13 g·m −2 ; soil daily total respiration ranges from 0.98―5.17 g·m −2 ; both daily variations of undisturbed community and soil respiration fluxes are significantly correlated ( p p < 0.01) with air temperatures and ground surface temperatures, but the correlativity with the soil temperature at 5 and 10 cm depths is relatively weak; multiple regression analysis indicates that about 80% of the difference in daily respiration of the undisturbed community among different phenological phases is induced by the variation of the aboveground biomass, while the variations of the remaining factors can jointly explain around 20% of the daily respiration variations of the whole grassland ecosystem; about 83% of the soil daily respiration variation of the different phenological phases is caused by 0―20 cm underground biomass. Besides, surface soil water content is also an important environmental factor affecting soil daily respiration variations of the Aneurolepidium chinense steppe, but its partial correlation coefficient with soil daily respiration amount does not reach the significance level of 0.05.