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浅谈如何减少产品库压
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作者 高桂庆 《福建轻纺》 2001年第10期63-66,共4页
该文阐明树立“市场观念、顾客至上”思想的重要性 ,并从抓管理、品牌、品种、质量、价格上入手 ,发挥人和设备的最大潜能 。
关键词 市场 产销平衡 企业 产品库压 经营管理
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浅谈压覆登记库矿产资源储量数据清理方法 被引量:2
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作者 许海涛 刘兴龙 +2 位作者 龙承涛 葛长峰 孟冬青 《城市地质》 2020年第3期308-311,共4页
由于近些年建设项目压占矿产资源的情况越来越多,为了保护和合理利用矿产资源,确保建设项目用地正常运行,有必要进一步摸清压覆资源储量情况,为政府决策提供科学准确的依据。在矿产资源储量管理工作中,压覆登记库是压覆信息的重要载体... 由于近些年建设项目压占矿产资源的情况越来越多,为了保护和合理利用矿产资源,确保建设项目用地正常运行,有必要进一步摸清压覆资源储量情况,为政府决策提供科学准确的依据。在矿产资源储量管理工作中,压覆登记库是压覆信息的重要载体。文章结合北京市矿产资源储量数据清理项目,介绍了压覆登记库资源储量的清理方法。通过资料收集整理,判断是否存在新增压覆资源储量、新增压覆量计算是否正确、是否存在压覆登记库,进而根据不同情况做出不同选择,当新增压覆资源储量未计算或计算错误,则需要通过块段分割法进行计算,最后通过修改完善压覆登记库形成清理后的成果数据库。 展开更多
关键词 覆登记 矿产资源 储量数据 清理
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超声诊断卵巢双侧库肯勃格氏肿瘤1例
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作者 林志霞 《国际医药卫生导报》 2002年第02B期107-108,共2页
1 病例报告 患者,女性,36,因发现腹部包块2周而入院,体格检查:神清,全身浅表淋巴结无肿大,腹部隆起如孕5个月,可触及巨大包块,上界平脐,两侧界至腋前线,下界深入盆腔,质中,囊突感,可活动腹软,肝脾未触及。妇检:子宫前位常大,质中,无压痛... 1 病例报告 患者,女性,36,因发现腹部包块2周而入院,体格检查:神清,全身浅表淋巴结无肿大,腹部隆起如孕5个月,可触及巨大包块,上界平脐,两侧界至腋前线,下界深入盆腔,质中,囊突感,可活动腹软,肝脾未触及。妇检:子宫前位常大,质中,无压痛,盆腔内可触及一包块,包块占据盆腔,可移动,囊实感,无压痛。入院后电子胃镜检查:慢性浅表性胃炎伴糜烂(胃窦、胃底为主)。 展开更多
关键词 超声诊断 卵巢双侧勃格肿瘤 临床表现
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高水头弧形闸门伸缩式水封止水试验研究 被引量:5
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作者 白绍学 张绍春 +3 位作者 李一兵 曹以南 罗文强 易春 《云南水力发电》 2009年第5期15-20,共6页
基于小湾水电站高水头闸门水封止水试验,对伸缩式水封的工作原理和止水效果进行了研究。试验证明,如果伸缩式水封及压板体型选择合理、材质选择合适,则可以满足承压水头200 m的止水要求。对伸缩水封的设计、制作和运行提出建议,以供工... 基于小湾水电站高水头闸门水封止水试验,对伸缩式水封的工作原理和止水效果进行了研究。试验证明,如果伸缩式水封及压板体型选择合理、材质选择合适,则可以满足承压水头200 m的止水要求。对伸缩水封的设计、制作和运行提出建议,以供工程参考。 展开更多
关键词 伸缩水封 材质 库压 闸门缝隙
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Construction and compression of Dwarf 被引量:1
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作者 向隆刚 冯玉才 桂浩 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第6期519-527,共9页
There exists an inherent difficulty in the original algorithm for the construction of Dwarf, which prevents it from constructing true Dwarfs. We explained when and why it introduces suffix redundancies into the Dwarf ... There exists an inherent difficulty in the original algorithm for the construction of Dwarf, which prevents it from constructing true Dwarfs. We explained when and why it introduces suffix redundancies into the Dwarf structure. To solve this problem, we proposed a completely new algorithm called PID. It bottom-up computes partitions of a fact table, and inserts them into the Dwarf structure. If a partition is an MSV partition, coalesce its sub-Dwarf; otherwise create necessary nodes and cells. Our performance study showed that PID is efficient. For further condensing of Dwarf, we proposed Condensed Dwarf, a more com- pressed structure, combining the strength of Dwarf and Condensed Cube. By eliminating unnecessary stores of “ALL” cells from the Dwarf structure, Condensed Dwarf could effectively reduce the size of Dwarf, especially for Dwarfs of the real world, which was illustrated by our experiments. Its query processing is still simple and, only two minor modifications to PID are required for the construction of Condensed Dwarf. 展开更多
关键词 Data cube DWARF Suffix coalescing Prefix path MSV partition Condensed Dwarf
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Automatic relational database compression scheme design based on swarm evolution 被引量:1
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作者 HU Tian-lei CHEN Gang +1 位作者 LI Xiao-yan DONG Jin-xiang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第10期1642-1651,共10页
Compression is an intuitive way to boost the performance of a database system. However, compared with other physical database design techniques, compression consumes large amount of CPU power. There is a trade-off bet... Compression is an intuitive way to boost the performance of a database system. However, compared with other physical database design techniques, compression consumes large amount of CPU power. There is a trade-off between the re- duction of disk access and the overhead of CPU processing. Automatic design and adaptive administration of database systems are widely demanded, and the automatic selection of compression schema to compromise the trade-off is very important. In this paper, we present a model with novel techniques to integrate a rapidly convergent agent-based evolution framework, i.e. the SWAF (SWarm Algorithm Framework), into adaptive attribute compression for relational database. The model evolutionally consults statistics of CPU load and IO bandwidth to select compression schemas considering both aspects of the trade-off. We have im- plemented a prototype model on Oscar RDBMS with experiments highlighting the correctness and efficiency of our techniques. 展开更多
关键词 Database compression Automatic physical database design Swarm evolution
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Simplified Computation of Reflective Overpressure in Closed Cuboid Space Due to Internal Explosion 被引量:2
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作者 田力 李忠献 周清 《Transactions of Tianjin University》 EI CAS 2010年第6期395-404,共10页
A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all node... A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all nodes on the walls of a cube with a side-length of 2 m are computed under a reference-charge explosion at each node of its inner space using the LS-DYNA software, and then are collected to form a reference database. Next, with the thought of the isoparametric finite element, an interpolating algori... 展开更多
关键词 closed cuboid space reference database reflective overpressure charge weight
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Experimental Study on Uniaxial Compressive Strength of Reservoir Ice 被引量:4
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作者 张丽敏 李志军 +1 位作者 贾青 黄文峰 《Transactions of Tianjin University》 EI CAS 2012年第2期112-116,共5页
Uniaxial compression experiments on horizontal and ervoir were conducted at different temperatures and strain rates vertical samples of first-year freshwater ice in a res- with an electronic universal machine equipped... Uniaxial compression experiments on horizontal and ervoir were conducted at different temperatures and strain rates vertical samples of first-year freshwater ice in a res- with an electronic universal machine equipped with low temperature cabinet. The results show that there is no difference between the strengths of two horizontal samples with grain sizes ranging from 1 to 4 mm and 4 to 14 mm, while the strength of the 1--4 mm vertical samples is 1.4 times higher than that of the 4--14 mm vertical samples because of the change of crystal structure. For different load- ing directions, the strengths of the horizontal samples do not differ from those of the vertical samples with the same grain sizes. The relation among the uniaxial compressive strength, strain rate and temperature was established through data analysis in both the ductile and brittle regions. 展开更多
关键词 freshwater ice compressive strength strain rate TEMPERATURE grain size
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Active earth pressure acting on retaining wall considering anisotropic seepage effect 被引量:4
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作者 HU Zheng YANG Zhong-xuan Stephen Philip WILKINSON 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1202-1211,共10页
This paper presents a general solution for active earth pressure acting on a vertical retaining wall with a drainage system along the soil-structure interface. The backfill has a horizontal surface and is composed of ... This paper presents a general solution for active earth pressure acting on a vertical retaining wall with a drainage system along the soil-structure interface. The backfill has a horizontal surface and is composed of cohesionless and fully saturated sand with anisotropic permeability along the vertical and horizontal directions. The extremely unfavourable seepage flow on the back of the retaining wall due to heavy rainfall or other causes will dramatically increase the active earth pressure acting on the retaining walls, increasing the probability of instability. In this paper, an analytical solution to the Laplace differential governing equation is presented for seepage problems considering anisotropic permeability based on Fourier series expansion method. A good correlation is observed between this and the seepage forces along a planar surface generated via finite element analysis. The active earth pressure is calculated using Coulomb's earth pressure theory based on the calculated pore water pressures. The obtained solutions can be degenerated into Coulomb's formula when no seepage exists in the backfill. A parametric study on the influence of the degree of anisotropy in seepage flow on the distribution of active earth pressure behind the wall is conducted by varying ratios of permeability coefficients in the vertical and horizontal directions,showing that anisotropic seepage flow has a prominent impact on active earth pressure distribution. Other factors such as effective internal friction angle of soils and soil/wall friction conditions are also considered. 展开更多
关键词 Active earth pressure Seepage Anisotropic permeability Retaining wall Fourier series expansion Cohesionless soils
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Experimental study on repair characteristics of damaged rock salt of underground gas storage 被引量:1
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作者 YIN Hong-wu MA Hong-ling +3 位作者 SHI Xi-lin LI Hao-ran GE Xin-bo GAO Ang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2185-2196,共12页
Damage in rock salt has significant implication on permeability, which affects the tightness of underground salt cavern gas storage in further. During the leaching of a salt cavern, the brine with formation temperatur... Damage in rock salt has significant implication on permeability, which affects the tightness of underground salt cavern gas storage in further. During the leaching of a salt cavern, the brine with formation temperature and pressure can promote the self-healing of rock salt in the excavation damage zone (EDZ). Laboratory tests were conducted to study the promoting effect. The permeability of two intact rock salt specimens was tested. Then they were damaged into two kinds of the state respectively through uniaxial compression. After that, they were put in saturated brine (with a temperature of 50℃ and pressure of 12 MPa, which we called the repair environment in this paper) for 7 d. Finally, the permeability and mechanical properties were obtained after the damaged specimens being repaired. The results show that the permeability of intact rock salt is below 10^-19 m^2;the permeability increases by more than two orders because of damage;the permeability decreases significantly after being repaired, which can be comparable to its intact state. Discussions of the repair mechanisms are presented (especially the mechanism of recrystallization), which may help to provide significant guidance for the study of the tightness and stability of gas storage facilities in China. 展开更多
关键词 gas storage rock salt PERMEABILITY DAMAGE uniaxial compression SELF-HEALING
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Comments on the editorial by Riggio&Ageloni on the ascitic fluid analysis
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作者 Anastasios Koulaouzidis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第48期6137-6138,共2页
Angeloni et al published a landmark study on the use of Coulter counters in spontaneous bacterial peritonitis(SBP)diagnosis.Riggio and Angeloni have recently published an editorial on the ascitic fluid analysis in dia... Angeloni et al published a landmark study on the use of Coulter counters in spontaneous bacterial peritonitis(SBP)diagnosis.Riggio and Angeloni have recently published an editorial on the ascitic fluid analysis in diagnosis and monitoring of SBP.Herein,some points of interest are discussed. 展开更多
关键词 PERITONITIS REAGENT DIPSTICK PARACENTESIS Guidelines ASCITES
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Experimental Performance of TJR02 as an Alternative Refrigerant to R22 in a Small-Scale Cold Storage
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作者 马洪亭 宋肖的 +1 位作者 杨国利 张于峰 《Transactions of Tianjin University》 EI CAS 2012年第5期330-334,共5页
A refrigerant mixture TJR02 was developed and the comparison experiment was performed on a singlestage vapor compression refrigeration system originally designed for R22.Experimental results show that TJR02 can be dir... A refrigerant mixture TJR02 was developed and the comparison experiment was performed on a singlestage vapor compression refrigeration system originally designed for R22.Experimental results show that TJR02 can be directly used in the system without modifying the original system or changing lubricant.By replacing R22 with TJR02,cooling rate gets faster and at least 20% of energy is saved.The actual detection in the standard test-bed verifies the experimental results and indicates that the adoption of TJR02 leads to greater efficiency and wider application.And the lower the refrigeratory temperature is,the more obvious the energy saving effects will be. 展开更多
关键词 alternative refrigerant TJR02 energy saving refrigeration capacity coefficient of performance
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Non-cooperative Space Target Estimation Algorithm Without Prior Information Dependence Based on Temporal Line of Sight Constraint
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作者 XIAO Hui ZHU Chongrui +3 位作者 LIU Xinqi YU Yifan SHENG Qinghong YANG Rui 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2024年第4期526-540,共15页
Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a p... Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning. 展开更多
关键词 motion parameter estimation estimation of impact point infrared early warning boost phase modeling trajectory database construction
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Finite element investigation of the poroelastic effect on the Xinfengjiang Reservoir-triggered earthquake 被引量:16
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作者 CHENG HuiHong ZHANG Huai +4 位作者 ZHU BoJing SUN YuJun ZHENG Liang YANG ShaoHua SHI YaoLin 《Science China Earth Sciences》 SCIE EI CAS 2012年第12期1942-1952,共11页
Coulomb failure stress changes (ΔCFS) are used in the study of reservoir-induced seismicity (RIS) generation.The threshold value of ΔCFS that can trigger earthquakes is an important issue that deserves thorough rese... Coulomb failure stress changes (ΔCFS) are used in the study of reservoir-induced seismicity (RIS) generation.The threshold value of ΔCFS that can trigger earthquakes is an important issue that deserves thorough research.The M s 6.1 earthquake in the Xinfengjiang Reservoir in 1962 is well acknowledged as the largest reservoir-induced earthquake in China.Therefore, it is a logical site for quantitative calculation of ΔCFS induced by the filling of the reservoir and for investigating the magnitude of CFS that can trigger reservoir seismic activities.To better understand the RIS mechanism, a three-dimensional poroelastic finite element model of the Xinfengjiang Reservoir is proposed here, taking into consideration of the precise topography and dynamic water level.We calculate the instant changes of stress and pore pressure induced by water load, and the time variation of effective stresses due to pore water diffusion.The CFS on the seismogenesis faults and the accumulation of strain energy in the reservoir region are also calculated.Primary results suggest that the reservoir impoundment increases both pore pressure and CFS on the fault at the focal depth.The diffusion of pore pressure was likely the main factor that triggered the main earthquake, whereas the elastic stress owing to water load was relatively small.The magnitude of CFS on seismogenesis fault can reach approximately 10 kPa, and the ΔCFS values at the hypocenter can be about 0.7-3.0 kPa, depending on the fault diffusion coefficient.The calculated maximum vertical subsidence caused by the water load in the Xinfengjiang Reservoir is 17.5 mm, which is in good agreement with the observed value of 15 mm.The accumulated strain energy owing to water load was only about 7.3×10 11 J, even less than 1% of the seismic wave energy released by the earthquake.The reservoir impoundment was the only factor that triggered the earthquake. 展开更多
关键词 Xinfengjiang Reservoir reservoir triggered seismicity Coulomb failure stress poroelasticity model finite element method
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Cotunneling transport in ultra-narrow gold nanowire bundles 被引量:1
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作者 Anais Loubat Walter Escoffier +5 位作者 Lise-Marie Lacroix Guillaume Viau Reasmey Tan Julian Carrey Benedicte Warot-Fonrose Bertrand Raquet 《Nano Research》 SCIE EI CAS CSCD 2013年第9期644-651,共8页
We investigate the charge transport in close-packed ultra-narrow (1.5 nm diameter) gold nanowires stabilized by oleylamine ligands. We give evidence of charging effects in the weakly coupled one-dimensional (1D) n... We investigate the charge transport in close-packed ultra-narrow (1.5 nm diameter) gold nanowires stabilized by oleylamine ligands. We give evidence of charging effects in the weakly coupled one-dimensional (1D) nanowires, monitored by the temperature and the bias voltage. At low temperature, in the Coulomb blockade regime, the current flow reveals an original cooperative multi-hopping process between 1D-segments of Au-NWs, minimising the charging energy cost. Above the Coulomb blockade threshold voltage and at high temperature, the charge transport evolves into a sequential tunneling regime between the nearest- nanowires. Our analysis shows that the effective length of the Au-NWs inside the bundle is similar to the 1D localisation length of the electronic wave function (of the order of 120 nm _+ 20 nm), but almost two orders of magnitude larger than the diameter of the nanowire. This result confirms the high structural quality of the Au-NW segments. 展开更多
关键词 ultra-narrow goldnanowires 1D nano-objects electronic transport variable cotunneling Coulomb blockade
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