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Design and characteristics of electric supercharger for diesel engine acceleration by additional rapid

YAO Chun-de, ZHOU Hong-xiu

《机械工程前沿（英文）》 2006年第1卷第4期页码 409-412 doi: 10.1007/s11465-006-0048-5

摘要： The ES (electric supercharger) driven by a high-speed brushless motor was developed to solve the problem of smoke caused by the turbocharger s sluggish response during acceleration. Its rotation speed was from 6 000 r/min to 24 000 r/min, and the maximum flux was 0.1 kg/s. The structural design of the electric supercharger is novel, which makes it easier to set the lubricating installation and to assemble. The velocity distribution at the outlet of the electric supercharger is determined by hot-wire anemometry under various rotation speeds in steady state. Furthermore, the trends of the flux and charge rate with various speeds were analyzed. In addition, the transient response was detected from the motor setup to smooth running within 10 s, 15 s, 20 s and 25 s respectively, and the characteristic of the transient flux is under pilot study. Research results indicate that the electric supercharger can respond rapidly with the great flux, and it is independent of the operating conditions of a diesel engine. Therefore, it is a feasible way to reduce smoke emission and improve the acceleration performance.

关键词： acceleration velocity distribution high-speed brushless turbocharger electric supercharger

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Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional

Alvyn P. Berg, Ting-An Fang, Hao L. Tang

《环境科学与工程前沿（英文）》 2019年第13卷第1期 doi: 10.1007/s11783-019-1098-3

摘要：

• Swimming pool water was studied for DBPs upon exposure to additional stimulants.

• DBP formation could be induced by residual chlorine and extended incubation.

• Urine led to a massive formation of chloroform with additional stimulants.

• Reactions between chlorine and anthropogenic organics were slow and long-lasting.

• Urine control and air ventilation should be on the priority list for pool management.

关键词： Trihalomethanes Haloacetic acids Chloroform Residual chlorine Anthropogenic organics Swimming pool water

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The clinicopathologic features of intraductal papillary mucinous neoplasms of the pancreas

QIN Xinyu, LIU Fenglin

《医学前沿（英文）》 2007年第1卷第2期页码 121-125 doi: 10.1007/s11684-007-0023-5

摘要： Since first described in 1982, intraductal papillary mucinous neoplasm (IPMN) has been the preferred term to describe the proliferation of the pancreatic ductal epithelium. It is totally different from pancreatic carcinoma in epi demiology, histology, pathology and prognosis. According to the site of involvement, IPMNs are classified into three categories, i.e. main duct type, branch duct type, and combined type. Most branch duct IPMNs are benign, whereas the other two types are often malignant. A large branch duct IPMN and marked dilation of the main pancreatic duct indicate the presence of adenoma at least. The additional existence of large mural nodules increases the possibility of malignancy in all types. The prognosis is more favorable after complete resection of benign and non-invasive malignant IPMNs. Malignant IPMNs that become more aggressive after parenchymal invasion necessitate adequate lymph node dissection. On the other hand, asymptomatic branch duct IPMNs without mural nodules can be observed without the need for resection for a considerable period of time. Our review addresses available data, current understanding, controversy, and future directions about IPMNs.

关键词： available additional existence necessitate intraductal papillary non-invasive

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Modified Bishop method for stability analysis of weakly sloped subgrade under centrifuge model test

《结构与土木工程前沿（英文）》 2021年第15卷第3期页码 727-741 doi: 10.1007/s11709-021-0730-z

摘要： The sliding forms of weak sloped and horizontal subgrades during the sliding process differ. In addition, the sliding form of weakly sloped subgrades exhibits considerable slippage and asymmetry. The accuracy of traditional slice methods for computing the stability safety factor of weakly sloped subgrades is insufficient for a subgrade design. In this study, a novel modified Bishop method was developed to improve the accuracy of the stability safety factor for different inclination angles. The instability mechanism of the weakly sloped subgrade was considered in the proposed method using the “influential force” and “additional force” concepts. The “additional force” reflected the weight effect of the embankment fill, whereas the “influential force” reflected the effect of the potential energy difference. Numerical simulations and experimental tests were conducted to evaluate the advantages of the proposed modified Bishop method. Compared with the traditional slice method, the error between the proposed method and the exact value is less than 32.3% in calculating the safety factor.

关键词： weakly sloped subgrade stability analysis additional force influential force modified Bishop method

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Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

ZHOU Hongbo, CHEN Zhuchang

《结构与土木工程前沿（英文）》 2007年第1卷第4期页码 458-463 doi: 10.1007/s11709-007-0062-7

摘要： Based on the comparative analysis of end effect on skin friction of displacement-pile (driven pile), the end effect on skin friction of bored pile is studied. The end effect on skin friction between driven pile and bored pile is different and the end effect on skin friction of bored pile is reduce of skin friction in the soil layer adjacent to the pile end. The degradation degree of skin friction is deduced with the increase of the distance from pile end. The concept of additional mud cake formed by the effect of cushion at the bottom of borehole during pouring concrete is introduced to explain the mechanism of end effect on skin friction of the bored pile. The test results of post-grouting piles indicate that the post-grouting technique is an effective way to improve the end effect on skin friction of bored pile.

关键词： distance different concept additional bottom

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施工与运营初期厚表土立井井壁受力实测研究

温德华

《中国工程科学》 2012年第14卷第2期页码 80-84

摘要：

采用井筒内外井壁现场埋设传感器的方法，建立由计算机控制的自动监测系统，实测大屯矿区某混合井井壁施工过程及之后一段时间的受力和变形演变规律。对实测结果进行分析，研究内外井壁的综合变形规律，可以预测井壁的长期安全性，为井壁破裂的预防和治理提供科学决策的依据。

关键词：井壁监测厚表土应变附加力

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Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

《机械工程前沿（英文）》 2022年第17卷第2期 doi: 10.1007/s11465-022-0676-4

摘要： The control system presently used in shield posture rectification is based on driver experience, which is marginally reliable. The study of the related theory is flawed. Therefore, a decision-making approach for the deviation correction trajectory and posture rectification load for an earth pressure balance (EPB) shield is proposed. A calculation model of posture rectification load of an EPB shield is developed by considering the interactions among the cutter head, shield shell, and ground. The additional position change during the shield attitude correction is highlighted. The posture rectification loads and shield behaviors results can be solved by the proposed method. The influences of the stratum distribution (i.e., bedrock height in the upper-soft and lower-hard strata) on shield behaviors and posture rectification loads are analyzed. Results indicated that the increase of pitch angle in the upper-soft and lower-hard strata causes a sharp rise in vertical displacement. The bedrock height increases the magnitudes of the required posture rectification moments when h_r/D > 0.5. For a tunnel with h_r/D ≤ 0.5, the variation of h_r/D has little effect on the posture rectification moments. Finally, the posture rectifying curves based on the theoretical model are compared with the target ones based on the double circular arc interpolation method. The required results can be obtained regardless of the soil–rock compound stratum distribution. The maximum rectification moment in the rock layer is almost 12.6 times that in the soil layer. Overall, this study provides a valuable reference for moment determination and the trajectory prediction of posture rectification in compound strata.

关键词： additional position change deviation correction trajectory earth pressure balance shield mechanical model posture rectification

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区域性沉降对高速铁路基础设施影响的研究

康高亮

《工程（英文）》 2016年第2卷第3期页码 374-379 doi: 10.1016/J.ENG.2016.03.014

摘要：

本文对高速铁路线路基础沉降及差异沉降的主要影响因素进行了分析，提出局部地下水开采是影响线路差异沉降的直接诱因。通过对不同差异沉降量下无砟轨道附加荷载及高速行车过程中车辆、轨道和桥梁动力响应的研究，初步提出了运营期线路基础差异沉降控制标准。

关键词：区域沉降差异沉降无砟轨道附加荷载车辆&ndash 轨道动力学

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基于微笑曲线理论的中国建筑业核心竞争力研究

叶娟,刘宏蛟

《中国工程科学》 2008年第10卷第12期页码 86-91

摘要：

建国以来，中国建筑业产值一直稳步提高，但低效率、低收益问题仍然没有得到解决。基于拓展服务领域、增加附加价值以提高我国建筑业核心竞争力的思路，从“广义的建筑业”和“广义的建设项目生命周期”出发，构建了建筑业的工程价值体系，并定义了相对附加经济价值这一概念。根据对目前我国建筑业现状的分析结果，研究了建设项目生命周期各个不同阶段附加价值的增值特点，做出了我国不同时期建筑业的微笑曲线，预测了我国建筑业未来的发展方向，最后探讨了提升我国建筑业核心竞争力的上、中、下游和整体发展战略。

关键词：建筑业核心竞争力微笑曲线相对附加经济价值全生命周期