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Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

《工程管理前沿（英文）》 2014年第1卷第2期页码 160-175 doi: 10.15302/J-FEM-2014024

摘要： This paper proposes an economic growth model based on the Six Basic Factors of Production and Xu Growth Rate Equation for the first time, which fills-in the deficits of the New Classical Economic Growth Model based on the Solow Model. The empirical analysis indicates that over the past three decades, the consumption of six basic factors of production had complicated relations with economic growth. In some years, the consumption rate of the basic factors of production was meager, but the economy witnessed relatively rocketing growth rate; in some years, the factors of production consumption rate was very high, but the economy growth rate slowed down. In general, economy grows at the expenses of huge consumption of four factors. There is an obvious characteristic of huge input and low efficiency. The average contribution rate of technological advance peaks in the middle, while it drops down at two ends. Noticeably, since 2004, the technology contribution rate generally shows a downward trend, reasons of which should be explored systematically in aspects like economic policy and industry structure with a view to boost further transformation of the macro-economy scientific growth model.

关键词： six basic factors of production economic growth model Xu Growth Rate Equation

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Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

GENG Jinju, WANG Qiang, WANG Xiaorong, NIU Xiaojun

《环境科学与工程前沿（英文）》 2007年第1卷第1期页码 120-124 doi: 10.1007/s11783-007-0022-4

摘要： Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4 12. The rates of phosphine production and release from lake sediments varied with temperature. 20?C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes.

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A total torque index for dynamic performance evaluation of a radial symmetric six-legged robot

Kejia LI, Xilun DING, Marco CECCARELL

《机械工程前沿（英文）》 2012年第7卷第2期页码 219-230 doi: 10.1007/s11465-012-0320-9

摘要：

This article focuses on the dynamic index and performance of a radial symmetric six-legged robot. At first the structure of the robot is described in brief and its inverse kinematics is presented. Then the dynamic model is formulated as based on the Lagrange equations. A novel index of total torque is proposed by considering the posture of the supporting legs. The new index can be used to optimize the leg’s structure and operation for consuming minimum power and avoiding unstable postures of the robot. A characterization of the proposed six-legged robot is obtained by a parametric analysis of robot performance through simulation using the presented dynamic model. Main influences are outlined as well as the usefulness of the proposed performance index.

关键词： six-legged robots dynamic modeling performance index

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Factors affecting production of nonaqueous peracetic acid in tubular packed reactors

ZHANG Tengyun, FAN Hongbo, ZHONG Li, CHUANG Karl

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 196-203 doi: 10.1007/s11705-008-0037-9

摘要： The synthesis of nonaqueous peracetic acid in acetone by acetaldehyde oxidation was carried out in a tubular packed reactor. The influencing factors of the reacting system including packing material, oxygen carrier, and reactor configuration were investigated. The results show that porous materials are inappropriate for peracetic acid synthesis and only non porous material with appropriate surface area can provide good peracetic acid selectivity and yield. Among the six kinds of packing material investigated, SA-5118 is the best one. As oxidizing gas, pure oxygen is superior to air. The optimum length-to-inner diameter ratio of the reactor is about 40. Under the proper reaction conditions, the highest peracetic acid yield of 84.15% and the highest selectivity of 93.34% can be achieved which indicates that the novel reacting system is effective and economical for nonaqueous peracetic acid production.

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The computational fluid dynamic modeling of downwash flow field for a six-rotor UAV

Yongjun ZHENG, Shenghui YANG, Xingxing LIU, Jie WANG, Tomas NORTON, Jian CHEN, Yu TAN

《农业科学与工程前沿（英文）》 2018年第5卷第2期页码 159-167 doi: 10.15302/J-FASE-2018216

摘要： The downwash flow field of the multi-rotor unmanned aerial vehicle (UAV), formed by propellers during operation, has a significant influence on the deposition, drift and distribution of droplets as well as the spray width of the UAV for plant protection. To study the general characteristics of the distribution of the downwash airflow and simulate the static wind field of multi-rotor UAVs in hovering state, a 3D full-size physical model of JF01-10 six-rotor plant protection UAV was constructed using SolidWorks. The entire flow field surrounding the UAV and the rotation flow fields around the six rotors were established in UG software. The physical model and flow fields were meshed using unstructured tetrahedral elements in ANSYS software. Finally, the downwash flow field of UAV was simulated. With an increased hovering height, the ground effect was reduced and the minimum current velocity increased initially and then decreased. In addition, the spatial proportion of the turbulence occupied decreased. Furthermore, the appropriate operational hovering height for the JF01-10 is considered to be 3 m. These results can be applied to six-rotor plant protection UAVs employed in pesticide spraying and spray width detection.

关键词： CFD simulation downwash flow field numerical analysis plant protection six-rotor UAV

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Basic consideration of research strategies for head and neck cancer

null

《医学前沿（英文）》 2012年第6卷第4期页码 339-353 doi: 10.1007/s11684-012-0213-7

摘要：

Head and neck cancer (HNC) consists of a group of malignancies affecting closely related anatomical regions of the upper aerodigestive tract (UADT), including the oral cavity, salivary glands, upper and lower jaw bones and facial skin; the nasal cavity, paranasal sinuses, pharynx, larynx and thyroid gland (although the latter is often excluded and considered as part of endocrine neoplasms). Of these, 90% of HNCs are histologically squamous cell carcinomas originating from the mucosal lining. These malignancies are strongly associated with certain environmental and life-style risk factors, principally tobacco in both smoked and smokeless forms, excessive alcohol consumption, diets poor in antioxidants and essential micronutrients, UV light, chemicals used in certain workplaces, and viruses, principally certain strains of human papillomavirus (HPV) and Epstein-Barr virus (EBV). These cancers are frequently aggressive in their biological behaviour with local invasion and metastasis to lymph nodes in the neck. Since most patients are already at late stages of disease at the time of diagnosis, the desirable practice of early diagnosis (first sign of the malignant lesion at an initial stage ) and early treatment, a critical priority to save lives and retain quality of life, is difficult to implement. Thus, primary prevention has been set as a key goal. This article aims to reinforce the basic knowledge of aetiology, key risk factors related to the development of head and neck cancer, basic features of clinical appearance of this group of cancers, and strategies for prevention and early detection. We also suggest basic research strategies on the basis of current knowledge, which should ultimately lead to the improvement of clinical management.

关键词： clinical management head and neck cancer prevention and early detection research strategies risk factors

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Sorption and desorption of pymetrozine on six Chinese soils

Mingxing GAO,Yingying LI,Hong YANG,Yucheng GU

《环境科学与工程前沿（英文）》 2016年第10卷第1期页码 1-10 doi: 10.1007/s11783-014-0715-4

摘要： Pymetrozine is a selective insecticide with a unique chemical structure and mode to control hemipteran and homopteran. While pymetrozine has brought great benefits to crop production by killing insects, its residues in soil may have a detrimental effect on environment. Therefore, it is of great importance to investigate its behaviors in soil. In this study, the sorption and desorption of pymetrozine on six Chinese soils were investigated using a batch equilibrium approach to understand its mobile behavior in the soils. Both sorption and desorption isotherms of pymetrozine were in good agreement with the Freundlich model. The sorption coefficient varied between 3.37 and 58.32 mL?g and the sorption isotherms were nonlinear, with 1/ ranging from 0.57 to 0.91. A regression equation was proposed to predict the sorption of pymetrozine on six different soil samples: log = 4.3708 − 4.5709 × log (pH in 0.01mol·L CaCl ) + 0.4700 × log OC% + 0.0057 × sand (%) + 0.0022 × CEC(clay), with = 0.9982. The organic carbon content of soil positively affected the sorption of pymetrozine, but soil pH had a negative effect on the sorption. Additionally, effects of CaCl concentration, soil to solution ratio and pesticide form were investigated. The sorption was promoted with an increase in soil to solution ratio and a decrease in CaCl concentration. The possible variation of the five formulated products of pymetrozine was also investigated.

关键词： desorption pymetrozine sorption soil

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A novel six-legged walking machine tool for

Jimu LIU, Yuan TIAN, Feng GAO

《机械工程前沿（英文）》 2020年第15卷第3期页码 351-364 doi: 10.1007/s11465-020-0594-2

摘要： The manufacture and maintenance of large parts in ships, trains, aircrafts, and so on create an increasing demand for mobile machine tools to perform operations. However, few mobile robots can accommodate the complex environment of industrial plants while performing machining tasks. This study proposes a novel six-legged walking machine tool consisting of a legged mobile robot and a portable parallel kinematic machine tool. The kinematic model of the entire system is presented, and the workspace of different components, including a leg, the body, and the head, is analyzed. A hierarchical motion planning scheme is proposed to take advantage of the large workspace of the legged mobile platform and the high precision of the parallel machine tool. The repeatability of the head motion, body motion, and walking distance is evaluated through experiments, which is 0.11, 1.0, and 3.4 mm, respectively. Finally, an application scenario is shown in which the walking machine tool steps successfully over a 250 mm-high obstacle and drills a hole in an aluminum plate. The experiments prove the rationality of the hierarchical motion planning scheme and demonstrate the extensive potential of the walking machine tool for operations on large parts.

关键词： legged robot parallel mechanism mobile machine tool in-situ machining

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能源生产革命的若干问题研究

黄其励,袁晴棠,韩涛

《中国工程科学》 2015年第17卷第9期页码 105-110

摘要：

坚持节约资源和保护环境，推动能源生产和消费革命，是实现我国能源工业可持续发展的重要保障。本文在对我国能源生产现状和世界能源发展趋势分析的基础上，凝练了我国能源生产革命的若干基本判断，回答了包括绿色煤炭、石油产量稳定并有增长、天然气产量较大幅度增长、大比例可再生能源、核能、CO2捕集利用与封存（CCS/CCUS）和新能源汽车等在内的能源生产革命的内涵和战略思路，提出了近期、中期、远期的战略目标、重点任务、政策支撑和若干重大建议。

关键词：能源生产革命；基本判断；战略思路；重点任务；政策建议

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舰船修理文件编制六维度管理方法研究

陈志敏,阳斌

《中国工程科学》 2015年第17卷第5期页码 83-89

摘要：

针对舰船基地级修理文件编制规律与技术特点，提出了成系统、科学的基地级修理文件编制六维度管理方法。在分析舰船装备基地级修理文件国外编制现状的基础上，针对修理文件编制难度大、内容多、涉及外协单位多、质量和进度管理难度大的特点，梳理出基地级修理文件体系，提出了从要求、样例、维修分析、知识库、质量管理、进度管理六个维度对修理文件编制的质量和进度进行管理的创新方法，从工程可操作性上对修理文件的编制管理方法进行了阐述，其研究成果对落实舰船装备基地级修理文件编制工作具有重要意义。

关键词：舰船；修理文件；六维度管理方法；维修分析

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Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

《医学前沿（英文）》 2009年第3卷第4期页码 452-458 doi: 10.1007/s11684-009-0080-z

摘要： The authors performed a meta-analysis of case-control studies that addressed whether reproductive factors and oral contraceptive use were associated with breast cancer by searching the MEDLINE, PubMed, Proquest, Embase, ScienceDirect, African Healthline, BMJ Health Intelligence and Chinese Periodical net databases for all English-language and Chinese-language papers published from January 1, 1997 to December 31, 2007. A total of 15 studies calculating pool ORs indicated that menopausal age >50yr [odds ratio (OR), 1.39; 95% confidence interval (CI), 1.22―1.57] and oral contraceptive use (OR, 2.12*, “*”: summary OR was adjusted; 95% CI, 1.24―3.62) were correlated with the increase in breast cancer risk while the summary OR based on number of full-term pregnancies ≥1 (OR, 0.63*; 95% CI, 0.60―0.68) and breast-feeding (OR, 0.76; 95% CI, 0.64―0.90) indicated no association with breast cancer risk. The correlation was statistically significant. Menopausal age >50yr and oral contraceptive use are positively correlated with an increase in breast cancer risk while breast-feeding and number of full-term pregnancies ≥1 are protective factors.

关键词： meta-analysis breast cancer risk factors reproductive factors oral contraceptive use

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Ultrasonic emulsification: basic characteristics, cavitation, mechanism, devices and application

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1560-1583 doi: 10.1007/s11705-022-2160-4

摘要： Emulsion systems are widely applied in agriculture, food, cosmetic, pharmaceutical and biomedical industries. Ultrasound has attracted much attention in emulsion preparation, especially for nanoemulsion, due to its advantages of being eco-friendly, cost-effective and energy-efficient. This review provides an overview for readers to the area of ultrasonic emulsification technology. It briefly introduces and summarizes knowledge of ultrasonic emulsification, including emulsion characteristics, acoustic cavitation, emulsification mechanism, ultrasonic devices and applications. The combination of microfluidics and ultrasound is highlighted with huge advantages in controlling cavitation phenomena and emulsification intensification. A novel scale of dμ_C^0.6/μ_D^0.33−E_V is proposed to be able to compare the energy efficiency of emulsion preparation in different devices.

关键词： nanoemulsion ultrasound microreactor multiphase energy

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Risk factors of prognosis after acute kidney injury in hospitalized patients

null

《医学前沿（英文）》 2017年第11卷第3期页码 393-402 doi: 10.1007/s11684-017-0532-9

摘要：

The risk factors, especially laboratory indicators, of prognosis after acute kidney injury (AKI) remain unclear. We conducted a retrospective survey of Chinese People’s Liberation Army General Hospital from January 1, 2012 to December 31, 2012 according to the AKI diagnosis standard issued by Kidney Disease Improving Global Outcomes. The epidemiological features and factors influencing hospital mortality and renal function recovery were evaluated through logistic regression analysis. Among 77 662 cases of hospitalized patients, 1387 suffered from AKI. The incidence rate and mortality of AKI were 1.79% and 14.56%, respectively. Multivariate logistic regression analysis revealed that high AKI stage, age greater than 80 years, neoplastic disease, low cardiac output, increased white blood cell count, and decreased platelet count and serum albumin levels were the risk factors affecting the mortality of AKI patients. Conversely, body mass index between 28 and 34.9 was a protective factor. Increased AKI stage, tumor disease, post-cardiopulmonary resuscitation, and RRT were the risk factors of renal function recovery upon discharge. In addition to traditional risk factors, white blood cell count, platelet count, albumin, and BMI were the predictors of the mortality of AKI patients. No laboratory indicators were found to be the risk factors of renal function recovery in AKI patients.

关键词： acute kidney injury risk factors prognosis

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“一带一路”沿线六大经济走廊优势产业及制造业国际合作现状分析

汤永川,潘云鹤,张雪,黄江杰

《中国工程科学》 2019年第21卷第4期页码 60-68 doi: 10.15302/J-SSCAE-2019.04.003

摘要：

“一带一路”建设正在从谋篇布局的“大写意”阶段转向精耕细作的“工笔画”阶段，这一转向升级对我国制造业国际合作提出更高的要求。本文基于联合国发布的国际贸易数据，以“一带一路”沿线六大经济走廊为重点研究对象，运用显性比较优势指数方法综合分析了六大经济走廊沿线国家比较优势产业。同时，应用多维尺度分析方法探讨了我国与六大经济走廊沿线国家总体贸易和制造业合作情况。最后，聚焦六大经济走廊沿线国家优势产业和要素禀赋，提出了我国与“一带一路”沿线国家制造业高质量合作的发展方向。

关键词： “一带一路”，制造业，六大经济走廊，显性比较优势指数，多维尺度分析

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Essential training steps to achieving competency in the basic intraoperative transesophageal echocardiography

null

《医学前沿（英文）》 2015年第9卷第1期页码 123-128 doi: 10.1007/s11684-014-0366-7

摘要：

Guidelines for the intraoperative transesophageal echocardiography (TEE) examination have defined a detailed standard for medical professionals, particularly anesthesiologists, on how a TEE exam should proceed. Over the years, TEE has gained substantial popularity and emerged as a preferred monitoring modality to aid in perioperative management and decision making during hemodynamic instability situations or critical care settings. TEE training pathways and practice guidelines have been well established in western countries and many regions of the world. However, TEE training and practice information for anesthesiologists are lacking in China. As innovative technologies develop, other educational models have emerged to aid in obtaining competency in basic TEE exam. Hence, establishing a consensus on the ideal TEE training approach for anesthesiologists in China is urgently needed. Developing an effective curriculum that can be incorporated into an anesthesiology resident’s overall training is also necessary to provide knowledge and skills toward competency in basic TEE exam. With evolving medical system reforms and increasing demands for intraoperative hemodynamic monitoring to accommodate surgical innovations, anesthesiology professionals are increasingly obliged to perform intraoperative TEE exams in their current and future practices. To overcome obstacles and achieve significant progress in using the TEE modality to help in intraoperative management and surgical decision making, publishing basic TEE training guidelines for China’s anesthesiologists is an important endeavor.

关键词： transesophageal echocardiography guidelines training competency