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Hydrological Simulation Using TRMM and CHIRPS Precipitation Estimates in the Lower Lancang-Mekong River Basin 预览
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作者 LUO Xian WU Wenqi +2 位作者 HE Daming LI Yungang JI Xuan 《中国地理科学:英文版》 SCIE CSCD 2019年第1期13-25,共13页
Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall station... Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall stations are sparse and unevenly distributed, and the transboundary characteristic makes the collection of precipitation data more difficult, which has restricted hydrological processes simulation. In this study, daily precipitation data from four datasets(gauge observations, inverse distance weighted(IDW) data, Tropical Rainfall Measuring Mission(TRMM) estimates, and Climate Hazards Group InfraRed Precipitation with Stations(CHIRPS) estimates), were applied to drive the Soil and Water Assessment Tool(SWAT) model, and then their capability for hydrological simulation in the Lower Lancang-Mekong River Basin were examined. TRMM and CHIRPS data showed good performances on precipitation estimation in the Lower Lancang-Mekong River Basin, with the better performance for TRMM product. The Nash-Sutcliffe efficiency(NSE) values of gauge, IDW, TRMM, and CHIRPS simulations during the calibration period were 0.87, 0.86, 0.95, and 0.93 for monthly flow, respectively, and those for daily flow were 0.75, 0.77, 0.86, and 0.84, respectively. TRMM and CHIRPS data were superior to rain gauge and IDW data for driving the hydrological model, and TRMM data produced the best simulation performance. Satellite-based precipitation estimates could be suitable data sources when simulating hydrological processes for large data-poor or ungauged watersheds, especially in international river basins for which precipitation observations are difficult to collect. CHIRPS data provide long precipitation time series from 1981 to near present and thus could be used as an alternative precipitation input for hydrological simulation, especially for the period without TRMM data. For satellite-based precipitation products, the differences in the occurrence frequencies and amounts of precipitation with different intensities would affect simulation re 展开更多
关键词 hydrological simulation satellite-based PRECIPITATION ESTIMATES spatial distribution of PRECIPITATION international RIVER the LOWER Lancang-Mekong RIVER Basin
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BLOW-UP PHENOMENA FOR A CLASS OF GENERALIZED DOUBLE DISPERSION EQUATIONS 预览
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作者 狄华斐 尚亚东 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第2期567-579,共13页
In this article, we study the blow-up phenomena of generalized double dispersion equations utt-uxx-uxxt + uxxxx-uxxtt= f(ux)x.Under suitable conditions on the initial data, we first establish a blow-up result for the ... In this article, we study the blow-up phenomena of generalized double dispersion equations utt-uxx-uxxt + uxxxx-uxxtt= f(ux)x.Under suitable conditions on the initial data, we first establish a blow-up result for the solutions with arbitrary high initial energy, and give some upper bounds for blow-up time T* depending on sign and size of initial energy E(0). Furthermore, a lower bound for blow-up time T^* is determined by means of a differential inequality argument when blow-up occurs. 展开更多
关键词 DOUBLE dispersion BLOW up UPPER BOUND lower BOUND
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Transurethral resection of prostate for acute urinary retention is linked to shorter survival in younger men
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作者 Jeremy Yuen-Chun Teoh Chi-Kwok Chan +7 位作者 Maggie Haitian Wang Chi-Ho Leung Eddie Shu-Yin Chan Peter Ka-Fung Chiu Chi-Hang Yee Hon-Ming Wong Simon See-Ming Hou Chi-Fai Ng 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第5期468-472,共5页
It is largely unknown whether lower urinary tract symptoms(LUTS)or acute retention of urine(AROU)is linked to shorter life expectancy in men.We conducted a multicenter,retrospective database analysis of patients under... It is largely unknown whether lower urinary tract symptoms(LUTS)or acute retention of urine(AROU)is linked to shorter life expectancy in men.We conducted a multicenter,retrospective database analysis of patients undergoing transurethral resection of prostate(TURP)to study their relationships.Multivariate Cox regression analysis and Kaplan-Meier analysis with stratification to age and indication of TURP were performed.We further performed an age-and sex-matched survival analysis with the general population using data from the Census and Statistics Department of the Hong Kong Special Administrative Region(Hong Kong,China).From January 2002 to December 2012,3496 patients undergoing TURP were included in our study,with 1764 patients in the LUTS group and 1732 patients in the AROU group.Old age,ischemic heart disease,cerebrovascular accident,and AROU were risk factors of mortality.Patients aged<70 years(adjusted hazard ratio[HR]:1.52,95%confidence interval[Cl]:1.11-2.09,P=0.010)and 70-80 years(adjusted HR:1.39,95%Cl:1.15-1.70,P-0.001)in the AROU group had worse survival than those in the LUTS group,but such difference was not demonstrated in patients aged>80 years.Compared to the general population,younger patients in the LUTS group appeared to have better survival(<70 years,P=0.091;70-80 years,P=0.011),but younger patients in the AROU group had worse survival(<70 years,P=0.021;70-80 years,P=0.003).For patients aged>80 years,survival was similar with the general population in both the LUTS and AROU groups.In conclusion,AROU at young age was associated with mortality,while early detection and management of LUTS may improve survival. 展开更多
关键词 acute retention of urine lower urinary tract symptoms MORTALITY transurethral resection of prostate
Optimized energy thresholds in a spectral computed tomography scan for contrast agent imaging 预览
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作者 Kai-Xin Huang Zhi Deng +1 位作者 Xiao-Fei Xu Yu-Xiang Xing 《核技术:英文版》 SCIE CAS CSCD 2019年第3期15-27,共13页
Spectral computed tomography (CT) based on photon counting detectors (PCDs) is a well-researched topic in the field of X-ray imaging. When PCD is applied in a spectral CT system, the PCD energy thresholds must be care... Spectral computed tomography (CT) based on photon counting detectors (PCDs) is a well-researched topic in the field of X-ray imaging. When PCD is applied in a spectral CT system, the PCD energy thresholds must be carefully selected, especially for K-edge imaging, which is an important spectral CT application. This paper presents a threshold selection method that yields better-quality images in K-edge imaging. The main idea is to optimize the energy thresholds ray-by-ray according to the targeted component coefficients, followed by obtaining an overall optimal energy threshold by frequency voting. A low-dose pre-scan is used in practical implementations to estimate the line integrals of the component coefficients for the basis functions. The variance of the decomposed component coefficients is then minimized using the Cramer–Rao lower bound method with respect to the energy thresholds. The optimal energy thresholds are then used to take a full scan and gain better image reconstruction with less noise than would be given by a full scan using the non-optimal energy thresholds. Simulations and practical experiments on imaging iodine and gadolinium solutions, which are commonly used as contrast agents in medical applications, were used to validate the method. The noise was significantly reduced with the same dose relative to the non-optimal energy thresholds in both simulations and in practical experiments. 展开更多
关键词 SPECTRAL CT CONTRAST AGENT IMAGING Cramer-Rao LOWER BOUND Thresholds optimization Kedge
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Adaptive Robust Control for a Lower Limbs Rehabilitation Robot Running Under Passive Training Mode 预览
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作者 Xiaolong Chen Han Zhao +1 位作者 Shengchao Zhen Hao Sun 《自动化学报:英文版》 CSCD 2019年第2期493-502,共10页
This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under passive training mode. In reality, uncertainties including modeling... This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under passive training mode. In reality, uncertainties including modeling error, initial condition deviation, friction force and other unknown external disturbances always exist in a LLRR system. So, it is necessary to consider the uncertainties in the unilateral man-machine dynamical model of the LLRR we described. In the dynamical model, uncertainties are(possibly fast) time-varying and bounded. However, the bounds are unknown. Based on the dynamical model, we design an adaptive robust control with an adaptive law that is leakagetype based and on the framework of Udwadia-Kalaba theory to compensate for the uncertainties and to realize tracking control of the LLRR. Furthermore, the effectiveness of designed control is shown with numerical simulations. 展开更多
关键词 Adaptive robust control LOWER LIMBS REHABILITATION ROBOT mechanical system PASSIVE training UNCERTAINTIES
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Geochemistry of upper Permian siliceous rocks from the Lower Yangtze region, southeastern China:implications for the origin of chert and Permian ocean chemistry
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作者 Zhi-Wei Liao Wen-Xuan Hu +1 位作者 Xiu-Gen Fu Zhong-Ya Hu 《石油科学:英文版》 SCIE CAS CSCD 2019年第2期252-266,共15页
The Permian Chert Event is of great significance to understanding the geological evolution of the entire Permian;however,the origin of widespread chert formation is debated. We report new geochemical data from deep-ma... The Permian Chert Event is of great significance to understanding the geological evolution of the entire Permian;however,the origin of widespread chert formation is debated. We report new geochemical data from deep-marine siliceous rocks of the upper Permian Da-long Formation, Lower Yangtze region, southeastern China. Their geochemical results show that these thin-bedded siliceous rocks have a clear biologic origin, with rare to no evidence of hydrothermal influence. The values of Al/(Al + Fe + Mn) and Eu/Eu* are 0.60-0.84(mean = 0.72) and 0.45-1.08(mean = 0.77), respectively, and Mn/Ti ratios are relatively low(mean = 0.72). The correlations of LaN/CeN, LaN/YbN, and Fe203/Ti02 with Al2O3/(Al2O3 + Fe2O3), along with the Ce anomaly, indicate that the Da-long siliceous rocks were deposited at a transitional zone between a continental margin and the open ocean;i.e., relatively close to terrestrial sediment input and far from hydrothermal activity. The accumulation of chert is related to its unique paleogeographic location in an equatorial setting with many submarine paleo-highlands.Intense upwelling and frequent local volcanism are the main factors that promoted the development of siliceous rocks in the studied area. Ocean acidification triggered by large-scale volcanism(Large Igneous Province) during the late Permian led to extensive silica precipitation and preservation. 展开更多
关键词 LOWER YANGTZE region Da-long Formation Siliceous rock Biological chert VOLCANISM
Effects of late diagenesis on primary reservoir quality of a quartz arenite unit: a case study from the lower Cretaceous successions of SW Iran
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作者 Amirhossein Enayati-Bidgoli Elham Saemi 《石油科学:英文版》 SCIE CAS CSCD 2019年第2期267-284,共18页
In this study, a sandstone interval of the lower Cretaceous successions in SW Iran is analyzed regarding the effects of late diagenesis on the alteration of primary reservoir quality and pore system. Petrological and ... In this study, a sandstone interval of the lower Cretaceous successions in SW Iran is analyzed regarding the effects of late diagenesis on the alteration of primary reservoir quality and pore system. Petrological and geochemical analyses indicate dominant quartz mineralogy(quartz arenite) deposited in distributary channel and mouth bar environments which is embedded in delta front to prodelta argillaceous sediments. Rather than mineralogy and some remaining primary(intergranular)porosity, several late(burial) diagenetic processes including multi-phase carbonate cementation, chlorite cementation, and chemical compaction, affected the reservoir quality. Most of the diagenetic processes had a decreasing effect on the primary reservoir quality. All recognized diagenetic features are related to burial diagenesis of the surrounding open marine shales(clay mineral transformation) and expelled diagenetic fluids. 展开更多
关键词 SILICICLASTIC RESERVOIR LATE DIAGENESIS RESERVOIR quality Rock type Lower CRETACEOUS SW Iran
Clinical differentiation of acute appendicitis and right colonic diverticulitis: A case-control study 预览
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作者 Yosuke Sasaki Fumiya Komatsu +9 位作者 Naoyasu Kashima Takahiro Sato Ikutaka Takemoto Sho Kijima Tadashi Maeda Takamasa Ishii Taito Miyazaki Yoshiko Honda Nagato Shimada Yoshihisa Urita 《世界临床病例杂志》 2019年第12期1393-1402,共10页
BACKGROUND Acute right colonic diverticulitis (ARCD) is an important differential diagnosis of acute appendicitis (AA) in Asian countries because of the unusually high prevalence of right colonic diverticula. Due to q... BACKGROUND Acute right colonic diverticulitis (ARCD) is an important differential diagnosis of acute appendicitis (AA) in Asian countries because of the unusually high prevalence of right colonic diverticula. Due to qualitative improvement and the high penetration rate of computed tomography (CT) scanning in Japan, differentiation of ARCD and AA mainly depends on this modality. But cost, limited availability, and concern for radiation exposure make CT scanning problematic. Differential findings of ARCD from AA are based on several small studies that used univariate comparisons from Korea and Taiwan. Previous studies on clinical and laboratory differences between AA and ARCD are limited. AIM To determine clinical differences between AA and ARCD for differentiation of these two diagnoses by creating a logistic regression model. METHODS We performed an exploratory single-center retrospective case-control study evaluating 369 Japanese patients (age ≥ 16 years), 236 (64.0%) with AA and 133 (36.0%) with ARCD, who were hospitalized between 2012 and 2016. Diagnoses were confirmed by CT images. We compared age, sex, onset-to-visit interval, epigastric/periumbilical pain, right lower quadrant (RLQ) pain, nausea/vomiting, diarrhea, anorexia, medical history, body temperature, blood pressure, heart rate, RLQ tenderness, peritoneal signs, leukocyte count, and levels of serum creatinine, serum C-reactive protein (CRP), and serum alanine aminotrans-ferase. We subsequently performed logistic regression analysis for differentiating AA from ARCD based on the results of the univariate analyses.RESULTS In the AA and ARCD groups, median ages were 35.5 and 41.0 years, respectively (p=0.011);median onset-to-visit intervals were 1 [interquartile range (IQR): 0-1] and 2 (IQR: 1-3) days, respectively (P < 0.001);median leukocyte counts were 12600 and 11500/mm3, respectively (P = 0.002);and median CRP levels were 1.1 (IQR: 0.2-4.1) and 4.9 (IQR: 2.9-8.5) mg/dL, respectively (P < 0.001). In the logistic regression model, odds ratios (ORs) 展开更多
关键词 Abdominal PAIN Acute ABDOMEN APPENDICITIS CLINICAL difference Creactive protein DIVERTICULITIS RIGHT lower quadrant PAIN
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Optimization of organic light emitting diode for HAT-CN based nano-structured device by study of injection characteristics at anode/organic interface
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作者 Neha JAIN O. P. SINHA Sujata PANDEY 《中国光电子学前沿:英文版》 EI CSCD 2019年第3期268-275,共8页
To increase the current density of the hole only device, 1, 4, 5, 8, 9, 11-hexaazatriphenylene-hexacarbonitrile (HAT-CN) material has been inserted in the device at the indium tin oxide (ITO)/organic interface. Since ... To increase the current density of the hole only device, 1, 4, 5, 8, 9, 11-hexaazatriphenylene-hexacarbonitrile (HAT-CN) material has been inserted in the device at the indium tin oxide (ITO)/organic interface. Since HATCN molecule can withdraw electrons, it can alter electronic properties of the electrodes and hence inserted between the organic/metal interfaces. This paper deals with the optimization of the thickness of organic-metal layers to enhance the efficiency. Also, efforts have been made to increase the current density and reduce the operating voltage of the device. The material 2, 7-bis [N, N-bis (4- methoxy-phenyl) amino]-9, 9-spirobifluorene (Meo-Spiro-TPD) is used to simulate the hole only device because it is a thermally stable hole transport material. Simulated results shows that better current density values can be achieved compared to fabricated one by optimizing the organic metal layer thickness. The best optimized layer thickness of 22 nm for Alq3, 25 nm for *CBP doped with Ir(ppy)3, 9 nm for Meo-Spiro TPD and 4 nm for HAT-CN which results in current density of 0.12 A/cm2 with a reduction in operating voltage by approximately 2 V. 展开更多
关键词 ORGANIC light emitting diode (OLED) 2 7-bis [NV-bis (4-methoxy-phenyl) amino]-9 9-spirobifluorene (Meo-Spiro-TPD) indium tin oxide (ITO) model higher occupied MOLECULAR ORBITAL (HOMO) lower unoccupied MOLECULAR ORBITAL (LUMO)
Distally based peroneus brevis muscle flap: A single centre experience
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作者 Subhash Sahu Amish Jayantilal +3 位作者 Gohil Shweta Patil Shashank Lamba Kingsly Paul Ashish Kumar Gupta 《中华创伤杂志:英文版》 CAS CSCD 2019年第2期108-112,共5页
Purpose: Defects aro und the distal one third of the leg and ankle are difficult to man age by con servative measures or simple split thickness skin graft. Distally based peroneus brevis muscle flap is a well describe... Purpose: Defects aro und the distal one third of the leg and ankle are difficult to man age by con servative measures or simple split thickness skin graft. Distally based peroneus brevis muscle flap is a well described flap for such defects. Methods: This is a retrospective analysis conducted on 25 patients with soft tissue and bony defects of distal third of lower leg and an kle, which were treated using distally based per on eus brevis muscle flap from January 2013 to January 2018. Information regarding patient demographics, etiology, size and location of defects and complications were collected. All patients were followed up for at least 3 months after surgery. Results: There were 21 males and 4 females with the mean age of 39 (5-76) years. The most comm on cause of injuries was road traffic accident, followed by complicated open injury. The average size of defects was 20 (4—50) cm^2. The mean operating time was 75 (60-90) min for flap harvest and inset. We had no patient with complete loss of the flap. Five patients (20%) had marginal necrosis of the flap and two patie nts have graft loss due to un derlyi ng hematoma and required sec on dary split thickness skin grafting. Conclusion: The distally based peroneus brevis muscle flap is a safe optio n w 让h reliable an atomy for small to moderate sized defects following low velocity injury around the ankle. The commonest complication encountered is skin graft loss which can be reduced by primary delayed grafting. 展开更多
关键词 Peroneus brevis FLAP REVERSE SURAL ARTERY Tendoachilles Lower LEG defects
Dynamical characteristic of measurement uncertainty under Heisenberg spin models with Dzyaloshinskii-Moriya interactions
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作者 Ying-Yue Yang Wen-Yang Sun +3 位作者 Wei-Nan Shi Fei Ming Dong Wang Liu Ye 《物理学前沿:英文版》 SCIE CSCD 2019年第3期123-131,共9页
The dynamics of measurement's uncertainty via entropy for a one-dimensional Heisenberg XYZ mode is examined in the presence of an inhomogeneous magnetic field and Dzyaloshinskii-Moriya (DM) interaction. It shows t... The dynamics of measurement's uncertainty via entropy for a one-dimensional Heisenberg XYZ mode is examined in the presence of an inhomogeneous magnetic field and Dzyaloshinskii-Moriya (DM) interaction. It shows that the uncertainty of interest is intensively in connection with the filed's temperature, the direction-oriented coupling strengths and the magnetic field. It turns out that the stronger coupling strengths and the smaller magnetic field would induce the smaller measurement's uncertainty of interest within the current spin model. Interestingly, we reveal that the evolution of the uncertainty exhibits quite different dynamical behaviors in antiferromagnetic (Ji> 0) and ferromagnetic (Ji< 0) frames. Besides, an analytical solution related to the systematic entanglement (i.e., concurrence) is also derived in such a scenario. Furthermore, it is found that the DM-interaction is desirably working to diminish the magnitude of the measurement's uncertainty in the region of high-temperature. Finally, we remarkably offer a result ful strategy to govern the ent ropy-based uncertainty through utilizing quantum weak measurements, being of fundamentally importance to quantum measurement estimation in the context of solid-state-based quantum information processing and comp ut at ion. 展开更多
关键词 MEASUREMENT uncertainty CONCURRENCE HEISENBERG XYZ chain WEAK MEASUREMENT lower BOUND
New Lower Bounds to Wrap-around L2-discrepancy for U-type Designs with Three-level
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作者 Zheng-hong WANG Hong QIN 《应用数学学报:英文版》 SCIE CSCD 2019年第3期513-520,共8页
The objective of this paper is to study the issue of uniformity on three-level U-type designs in terms of the wrap-around L2-discrepancy.Based on the known formula,we present a new lower bound of wrap-around L2-discre... The objective of this paper is to study the issue of uniformity on three-level U-type designs in terms of the wrap-around L2-discrepancy.Based on the known formula,we present a new lower bound of wrap-around L2-discrepancy for three-level U-type designs and compare it with those existing ones through figures,numerical simulation and illustrative examples. 展开更多
关键词 U-type DESIGNS wrap-around L2-discrepancy lower BOUND
Health concerns of veterans with high-level lower extremity amputations
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作者 Elahe Faraji Mostafa Allami +4 位作者 Nafiseh Feizollahi Amir Karimi Amir Yavari Mohammadreza Soroush Majid Moudi 《军事医学研究:英文版》 CAS CSCD 2019年第2期117-127,共11页
Background: To identify health concerns of veterans with high-level lower extremity amputations.Methods: Through a cross-sectional study, general practitioners, an orthopedic specialist, psychologists, psychiatrists,p... Background: To identify health concerns of veterans with high-level lower extremity amputations.Methods: Through a cross-sectional study, general practitioners, an orthopedic specialist, psychologists, psychiatrists,physiotherapist and prosthetists examined 100 veterans using a short-form health-related quality of life questionnaire(SF-36) that assessed their ability to perform activities of daily living(ADL), instrumental activities of daily living(IADL) and life satisfaction(SWLS) after hip disarticulation or hemi-pelvectomy amputations. The assessment tool was designed to gather statistically useful information about their health needs.Results: The means of the Physical Component Summary(PCS), Mental Component Summary(MCS), SWLS, ADL and IADL were 48.58±29.6, 33.33±22.0, 19.30±7.7, 48.10±10.5 and 5.08±1.8, respectively. Somatization, depression, and anxiety were the most prevalent disorders;among the veterans who were visited by psychiatrists, 11.6% had a history of hospitalization in a psychiatry section, and 53.2% had a psychiatric visit. Regardless of their injury in battle, 34% of veterans were hospitalized. Hearing problems were common, and about four-fifths of the participants suffered from at least one orthopedic condition. Neuroma(49%) was the most common stump-related complication during orthopedic evaluations, though the prevalence of phantom pain was 81% during the pain assessment. A total of 87% of the participants had a history of wearing a prosthesis, but only 29% wore a prosthesis at the time of the present study.The Canadian-type of prosthesis was uncomfortable and not useful(27%) and excessively heavy(10%) according to the amputees.Conclusions: Understanding veterans’ characteristics and special needs are important to make sure that enough facilities and services are afforded to them. These findings emphasize the importance of paying close attention to different dimensions of health in veterans and can help health providers identify health needs and make regular assessments. 展开更多
关键词 War-related trauma High level lower EXTREMITY AMPUTATION HEALTH needs assessment
Designing Uniform Computer Sequential Experiments with Mixture Levels Using Lee Discrepancy
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作者 ELSAWAH A M 《系统科学与复杂性学报:英文版》 SCIE EI CSCD 2019年第2期681-708,共28页
Computer experiments are constructed to simulate the behavior of complex physical systems. Uniform designs have good performance in computer experiments from several aspects. In practical use, the experimenter needs t... Computer experiments are constructed to simulate the behavior of complex physical systems. Uniform designs have good performance in computer experiments from several aspects. In practical use, the experimenter needs to choose a small size uniform design at the beginning of an experiment due to a limit of time, budget, resources, and so on, and later conduct a follow up experiment to obtain precious information about the system, that is, a sequential experiment. The Lee distance has been widely used in coding theory and its corresponding discrepancy is an important measure for constructing uniform designs. This paper proves that all the follow up designs of a uniform design are uniform and at least two of them can be used as optimal follow up experimental designs. Thus, it is not necessary that the union of any two uniform designs yields a uniform sequential design. Therefore, this article presents a theoretical justification for choosing the best follow up design of a uniform design to construct a uniform sequential design that involves a mixture of ω≥ 1 factors with β_k ≥ 2, 1 ≤ k ≤ωlevels. For illustration of the usage of the proposed results, a closer look is given at using these results for the most extensively used six particular cases, three symmetric and three asymmetric designs, which are often met in practice. 展开更多
关键词 COMPUTER experiment LEE DISCREPANCY LEE distance lower bound SEQUENTIAL DESIGN UNIFORM DESIGN
Estimations on upper and lower bounds of solutions to a class of tensor complementarity problems
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作者 Yang XU Weizhe GU Zheng-Hai HUANG 《中国数学前沿:英文版》 SCIE CSCD 2019年第3期661-671,共11页
We introduce a class of structured tensors, called generalized row strictly diagonally dominant tensors, and discuss some relationships between it and several classes of structured tensors, including nonnegative tenso... We introduce a class of structured tensors, called generalized row strictly diagonally dominant tensors, and discuss some relationships between it and several classes of structured tensors, including nonnegative tensors, Btensors, and strictly copositive tensors. In particular, we give estimations on upper and lower bounds of solutions to the tensor complementarity problem (TCP) when the involved tensor is a generalized row strictly diagonally dominant tensor with all positive diagonal entries. The main advantage of the results obtained in this paper is that both bounds we obtained depend only on the tensor and constant vector involved in the TCP;and hence, they are very easy to calculate. 展开更多
关键词 TENSOR complementarity problem (TCP) generalized ROW STRICTLY diagonally DOMINANT TENSOR upper and lower BOUNDS of SOLUTIONS
Asymptotic behavior for sums of non-identically distributed random variables 预览
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作者 YU Chang-jun CHENG Dong-ya 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2019年第1期45-54,共10页
For any given positive integer m,let Xi,1≤i≤m be m independent random variables with distributions Fi,1≤i≤m.When all the summands are nonnegative and at least one of them is heavy-tailed,we prove that the lower li... For any given positive integer m,let Xi,1≤i≤m be m independent random variables with distributions Fi,1≤i≤m.When all the summands are nonnegative and at least one of them is heavy-tailed,we prove that the lower limit of the ratio P(∑i=1^mXi>x)/∑i=1^mFi(x)equals 1 as x→∞.When the summands are real-valued,we also obtain some asymptotic results for the tail probability of the sums.Besides,a local version as well as a density version of the above results is also presented. 展开更多
关键词 lower limits UPPER limits heavy-tailed DISTRIBUTIONS local DISTRIBUTIONS DENSITIES
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Mandated health insurance increases rates of elective knee surgery 预览
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作者 Daniel Kim Woo Do +3 位作者 Shahein Tajmir Brandon Mahal Joe DeAngelis Arun Ramappa 《世界骨科杂志(英文版)》 2019年第2期81-89,共9页
BACKGROUND The recent federal ruling to against Affordable Care Act(ACA),specifically the mandate requiring people to buy insurance,has once again brought the healthcare reform debate to the spotlight.The ACA increase... BACKGROUND The recent federal ruling to against Affordable Care Act(ACA),specifically the mandate requiring people to buy insurance,has once again brought the healthcare reform debate to the spotlight.The ACA increased the number of insured Americans through the development of subsidized healthcare plans and health insurance exchanges.Insurance-based differences in the rate of upper extremity elective orthopaedic surgery have been described before and after healthcare reform in Massachusetts,where a similar mandate was put into place years before the ACA was passed.However,no comprehensive study has evaluated insurance-based differences of knee elective surgery before and after reform.AIM To investigate how an individual mandate to purchase health insurance affects rates of knee surgery.METHODS A retrospective review was performed within an orthopaedic surgery department at a tertiary-care,academic medical center in Massachusetts.The rate of elective knee surgery performed before and after the healthcare reform(2005-2006 and 2007-2010,respectively)was calculated.The patients were categorized by insurance type(Commonwealth Care,Medicare,Medicaid,private insurance,Workers’Compensation,TriCare,and Uninsured).Usingχ^2 testing,differences in rates of surgery between the pre-reform and post-reform period and among insurance subgroups were calculated.RESULTS Rate of surgery increased in the post-reform period(pre-reform 8.07%(95%CI:7.03%-9.11%),post-reform 9.38%(95%CI:8.74%-10.03%)(P=0.04)and was statistically significant.When the insurance groups and insurance types were compared,the rates of surgery are not significantly different before or after reform.CONCLUSION The increase in the rate of elective knee surgery in the post-reform period suggests that health care reform in Massachusetts has been successful in decreasing the uninsured population and may increase health care expenditures.This is a hypothesis generating study that suggests further avenues of study on how mandated coverage may change healthcare utiliz 展开更多
关键词 Healthcare reform ELECTIVE SURGERY LOWER EXTREMITY Affordable Care Act ORTHOPAEDIC SURGERY
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Early Jurassic basal sauropodomorpha dominated tracks from Guizhou,China:Morphology,ethology,and paleoenvironment 预览
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作者 Lida Xing Martin G.Lockley +4 位作者 Dongjie Tang Hendrik Klein Guangzhao Peng Yong Ye Baoqiao Hao 《地学前缘:英文版》 CAS CSCD 2019年第1期229-240,共12页
The newly discovered large(350 m^2) Yantan dinosaur tracksite, in the Lower Jurassic Ziliujing Formation of Guizhou Province, China, reveals at least 250 footprints of which ~97 can be resolved into trackways of sauro... The newly discovered large(350 m^2) Yantan dinosaur tracksite, in the Lower Jurassic Ziliujing Formation of Guizhou Province, China, reveals at least 250 footprints of which ~97 can be resolved into trackways of sauropodomorphs. All the trackways are sub parallel likely indicating gregarious behavior. One theropod track(cf. Grallator) was recorded. The sauropodomorph tracks predominantly represent quadrupedal progression(Morphotype A), and footprint morphology is similar to the ichnospecies Liujianpusshunan, characterized by outward pes rotation. Three trackways indicate bipedal progression, and two of these(Morphotype B) indicate inward pes rotation, accompanied by elongate pes digit scratch marks. For the latter phenomenon three possible scenarios are discussed:(1) significant rotation changes accompanying changes in gait,(2) swimming behavior,(3) formation of undertracks.Sedimentological evidence indicates the tracks were made on a linguloid rippled, muddy, immature sandstone substrate characterized by significant differences in substrate consistency across the trackbearing surface. Microbially induced sedimentary structures(MISS) characterized by distinctive wrinkle marks indicate a stressed, probably semi-arid, paleoenvironment that was not conducive to habitation by invertebrate organisms. This is consistent with other evidence that Lower Jurassic sauropodomorph tracks are often associated with semi-arid paleoenvironments. 展开更多
关键词 Sauropodomorph TRACKS Ziliujing formation Lower JURASSIC GUIZHOU Province
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Major breakthrough of Well Gaotan 1 and exploration prospects of lower assemblage in southern margin of Junggar Basin, NW China 预览
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作者 DU Jinhu ZHI Dongming +5 位作者 LI Jianzhong YANG Disheng TANG Yong QI Xuefeng XIAO Lixin WEI Lingyun 《石油勘探与开发:英文版》 2019年第2期216-227,共12页
Well Gaotan 1 was tested a high yield oil and gas flow of more than 1 000 m~3 a day in the Cretaceous Qingshuihe Formation,marking a major breakthrough in the lower assemblage of the southern margin of Junggar Basin. ... Well Gaotan 1 was tested a high yield oil and gas flow of more than 1 000 m~3 a day in the Cretaceous Qingshuihe Formation,marking a major breakthrough in the lower assemblage of the southern margin of Junggar Basin. The lower assemblage in the southern margin of the Junggar Basin has favorable geological conditions for forming large Petroleum fields, including:(1) Multiple sets of source rocks, of which the Jurassic and Permian are the main source rocks, with a large source kitchen.(2) Multiple sets of effective reservoirs,namely Cretaceous Qingshuihe Formation, Jurassic Toutunhe Formation and the Khalza Formation etc.(3) Regional thick mudstone caprock of Cretaceous Tugulu Group, generally with abnormally high pressure and good sealing ability.(4) Giant structural traps and litho-stratigraphic traps are developed. The northern slope also has the conditions for large-scale litho-stratigraphic traps.(5) Static elements such as source rocks, reservoirs and caprocks are well matched, and the dynamic evolution is suitable for large oil and gas accumulation. The lower assemblage of the southern margin of the Junggar Basin has three favorable exploration directions, the Sikeshu Sag in the west part, the large structures in the middle and eastern part, and the northern slope. 展开更多
关键词 southern MARGIN of JUNGGAR Basin WELL Gaotan 1 LOWER ASSEMBLAGE accumulation condition exploration direction
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Structural Characteristics of Lycium ruthenicum Community & Soil Properties on Different Types of Desert Rangeland in the Lower Reaches of Shiyang River 预览
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作者 Chunxiu GUO Lide WANG +5 位作者 Fanglan HE Junmei MA Jinhui LI Fubo AN Hongbo YUAN Kailin LIU 《药用植物研究(英文版)》 2019年第2期58-65,共8页
[Objectives] To study structural characteristics of Lycium ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River, and provide theoretical basis for ecolo... [Objectives] To study structural characteristics of Lycium ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River, and provide theoretical basis for ecological protection and management in the lower reaches of Shiyang River.[Methods] One-way ANOVA analysis and correlation analysis were carried out with the aid of SPSS19.0 software for different types of desert rangeland soils.[Results](i) Among the communities surveyed, there are 31 species belonging to 9 families and 28 genera, including 12 shrub plants, 8 perennial herbs and 11 annual herbs. There are more single genus, occupying 50% of total genus. L. ruthenicum occupies an important position in the community with relatively higher importance value. It plays a dominated role in the community.(ii) In the soils with depths of 0-10 cm, 10-20 cm, 20-40 cm and 40-60 cm in different types of desert rangeland, the organic carbon contents in the saline alkali soil were the highest, with the values of 1.08%, 0.98%, 0.89% and 0.972%, respectively. Compared with that in sandy land, soil organic carbon in saline alkali land(0-10 cm) had the significant difference(P<0.05), available soil potassium in saline alkali land(except the depth of 20-40 cm) and the total phosphorus content in saline alkali land(0-10 cm) had the significant difference(P<0.05), the total soil nitrogen, alkali-hydrolyzable nitrogen, available phosphorus and the total potassium content had no significant difference(P>0.05). Soil organic carbon, available soil phosphorus in saline alkali land, total soil potassium on sand dune and total soil phosphorus in saline alkali land and gravel in different soil layers of the same type of desert rangeland had distinct aggregation effect.(iii) The soil microbial biomass in different types of desert rangeland displayed from high to low as saline alkali land > sandy land > fixed and semi fixed sandy land > gravel. The discrepancy of soil microbial biomass varied in different types of desert rangeland. Th 展开更多
关键词 Lower reaches of Shiyang River DESERT RANGELAND LYCIUM ruthenicum COMMUNITY VEGETATION characteristics Soil properties
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