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Optimization of Compound Coptis Ointment Extraction through the Integration of Pharmacodynamic Indices and Orthogonal Test
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作者 Jin ZHOU Xiuli ZHOU +3 位作者 Yu ZHOU Ming MEI Qiang GAO Xinguo LIU 《Medicinal Plant》 CAS 2023年第5期32-35,共4页
[Objectives]To determine the optimal reflux extraction process conditions for Compound Coptis Ointment.[Methods]The study employed the orthogonal experimental design method and drug-sensitive disc agar diffusion metho... [Objectives]To determine the optimal reflux extraction process conditions for Compound Coptis Ointment.[Methods]The study employed the orthogonal experimental design method and drug-sensitive disc agar diffusion method to evaluate the extraction rate,berberine hydrochloride content,and bacteriostatic ring diameter of the extract as comprehensive indices,and optimized the extraction process conditions of Compound Coptis Ointment using ethanol reflux.[Results]Based on the results of comprehensive indices,the optimal reflux extraction conditions for Compound Coptis Ointment were determined to be soaking in 1.5 times the amount of 70%ethanol for 2 h,followed by two extractions with 6 times the amount of 70%ethanol for 1 h each time.Three verification tests were conducted under the optimal process conditions.The yield of the extract was 28.32%±0.53%,the content of berberine hydrochloride was 4.68%±0.45%,and the diameter of the bacteriostatic ring was(2.5±0.2)cm.[Conclusions]The extract had higher drug content and exhibited better antibacterial effects.The optimized extraction process is simple,stable,and reliable,and can be effectively used to optimize the extraction process of Compound Coptis Ointment. 展开更多
关键词 Compound Coptis Ointment orthogonal test Antibacterial test Extraction process
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Fecal microbial biomarkers combined with multi-target stool DNA test improve diagnostic accuracy for colorectal cancer 被引量:2
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作者 Jin-Qing Fan Wang-Fang Zhao +4 位作者 Qi-Wen Lu Fu-Rong Zha Le-Bin Lv Guo-Liang Ye Han-Lu Gao 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第8期1424-1435,共12页
BACKGROUND Colorectal cancer(CRC)is a major global health burden.The current diagnostic tests have shortcomings of being invasive and low accuracy.AIM To explore the combination of intestinal microbiome composition an... BACKGROUND Colorectal cancer(CRC)is a major global health burden.The current diagnostic tests have shortcomings of being invasive and low accuracy.AIM To explore the combination of intestinal microbiome composition and multi-target stool DNA(MT-sDNA)test in the diagnosis of CRC.METHODS We assessed the performance of the MT-sDNA test based on a hospital clinical trial.The intestinal microbiota was tested using 16S rRNA gene sequencing.This case-control study enrolled 54 CRC patients and 51 healthy controls.We identified biomarkers of bacterial structure,analyzed the relationship between different tumor markers and the relative abundance of related flora components,and distinguished CRC patients from healthy subjects by the linear discriminant analysis effect size,redundancy analysis,and random forest analysis.RESULTS MT-sDNA was associated with Bacteroides.MT-sDNA and carcinoembryonic antigen(CEA)were positively correlated with the existence of Parabacteroides,and alpha-fetoprotein(AFP)was positively associated with Faecalibacterium and Megamonas.In the random forest model,the existence of Streptococcus,Escherichia,Chitinophaga,Parasutterella,Lachnospira,and Romboutsia can distinguish CRC from health controls.The diagnostic accuracy of MT-sDNA combined with the six genera and CEA in the diagnosis of CRC was 97.1%,with a sensitivity and specificity of 98.1%and 92.3%,respectively.CONCLUSION There is a positive correlation of MT-sDNA,CEA,and AFP with intestinal microbiome.Eight biomarkers including six genera of gut microbiota,MT-sDNA,and CEA showed a prominent sensitivity and specificity for CRC prediction,which could be used as a non-invasive method for improving the diagnostic accuracy for this malignancy. 展开更多
关键词 Gut microbiome Colorectal cancer Diagnostic model multi-target stool DNA test Tumor biomarker
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Influence of multiple structural parameters on interior ballistics based on orthogonal test methods 被引量:7
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作者 Chao-bin Hu Xiao-bing Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期690-697,共8页
Influence of multiple structural parameters on the performance of a gun launch system driven by highpressure reactive gases is important for structural design and performance adjustment.A coupled lumped parameter mode... Influence of multiple structural parameters on the performance of a gun launch system driven by highpressure reactive gases is important for structural design and performance adjustment.A coupled lumped parameter model was utilized to predict the propellant combustion,and a dynamic finite element method was applied to approximate the mechanical interactions between the projectile and the barrel.The combustion and the mechanical interactions were coupled through a user subroutine interface in ABAQUS.The correctness and the capability of the finite element approximations in capturing small structural changes were validated by comparing predicted resistance with experiments.Based on the coupled model,the influence of structural parameters of a medium-caliber gun on the system performance was investigated.In order to reduce the research costs,orthogonal tests were designed to investigate the comprehensive effects of the parameters.According to statistical analysis,the important order of the structural parameters on the launching process was obtained.The results indicate that the influence of the width of the rotating band stands out among the studied parameters in the gun.The work provides a method to investigate the influence of multiple parameters on system performance and gives guidance for controlling the system performance. 展开更多
关键词 MULTIPLE PARAMETERS COUPLED model COMBUSTION Sensitivity analysis orthogonal test
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Orthogonal tests of copper-clad aluminum bimetal continuous casting by nitrogen pressure core-illing 被引量:3
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作者 Xue Zhiyong Liang He +1 位作者 Yu Wanhua Wu Chunjing 《China Foundry》 SCIE CAS 2013年第6期385-390,共6页
To provide theoretical basis and practical guidance for preparing composite rods by direct continuous casting, copper-clad aluminum composite rods of external copper layer diameter 12 mm and inner aluminum core diamet... To provide theoretical basis and practical guidance for preparing composite rods by direct continuous casting, copper-clad aluminum composite rods of external copper layer diameter 12 mm and inner aluminum core diameter 8 mm were manufactured. Orthogonal tests consisted of three factors and three levels were carried out to research the effects of melting copper temperature, continuous casting speed and nitrogen pressure on the performance of composite rods. Results showed that nitrogen pressure is the most important factor in influencing the surface quality; continuous casting speed is the most important factor in influencing copper & aluminum inter diffusion amount. Nitrogen pressure can noticeably improve the surface quality and make the rods easily be drawn out, but the surface quality does not show visible improvement when the nitrogen pressure is above 0.05 MPa. Measured by tests, the compound layer can be divided into three types according to its cladding layer degree: deficient cladding, normal cladding and excess cladding. The diameter of normal copper-clad aluminum composite rods can be successfully drawn less than 0.6 mm without annealing. 展开更多
关键词 copper-clad aluminum nitrogen pressing continuous casting orthogonal test
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Optimization of a Centrifugal Pump Used as a Turbine Impeller By Means of an Orthogonal Test Approach 被引量:3
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作者 Peng Tian Jun Huang +1 位作者 Weidong Shi Ling Zhou 《Fluid Dynamics & Materials Processing》 EI 2019年第2期139-151,共13页
A prototype centrifugal pump with a specific speed of 110 is used to investigate and optimize the performances of a turbine for power generation.Particular attention is given to the design of the internal impeller.The... A prototype centrifugal pump with a specific speed of 110 is used to investigate and optimize the performances of a turbine for power generation.Particular attention is given to the design of the internal impeller.The internal flow field is simulated in the framework of a commercial computational fluid dynamics software(ANSYS).Four geometrical parameters of the impeller are considered,i.e.,the inlet diameter,the inlet width,the blade number,and the blade angle.The optimization is carried out on the basis of a three-level approach relying on an orthogonal test method.The results of the numerical simulations show good agreement with the experimental tests under different flow conditions.In accordance with the L9(34)design table,the head and efficiency under the rated flow rate of the nine designed schemes are calculated and processed with the method of range analysis to obtain an optimized model. 展开更多
关键词 Pump AS TURBINE numerical calculation orthogonal test OPTIMIZATION design
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Mathematical model for abrasive suspension jet cutting based on orthogonal test design 被引量:3
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作者 胡贵华 朱文华 +5 位作者 蔡红霞 徐翀 柏余杰 程俊 苑进 俞涛 《Journal of Shanghai University(English Edition)》 CAS 2009年第1期37-44,共8页
This paper describes the application of orthogonal test design coupled with non-linear regression analysis to optimize abrasive suspension jet (AS J) cutting process and construct its cutting model. Orthogonal test ... This paper describes the application of orthogonal test design coupled with non-linear regression analysis to optimize abrasive suspension jet (AS J) cutting process and construct its cutting model. Orthogonal test design is applied to cutting stainless steel. Through range analysis on experiment results, the optimal process conditions for the cutting depth and the kerr ratio of the bottom width to the top width can be determined. In addition, the analysis of ranges and variances are all employed to identify various factors: traverse rate, working pressure, nozzle diameter, standoff distance which denote the importance order of the cutting parameters affecting cutting depth and the kerf ratio of the bottom width to the top width. ~rthermore, non-linear regression analysis is used to establish the mathematical models of the cutting parameters based on the cutting depth and the kerr ratio. Finally, the verification experiments of cutting parameters' effect on cutting performance, which show that optimized cutting parameters and cutting model can significantly improve the prediction of the cutting ability and quality of ASJ. 展开更多
关键词 abrasive suspension jet (AS J) orthogonal test design cutting depth the kerf ratio of the bottom width to the top width non-linear regression analysis verification experiment
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Orthogonal Test About Biogas Upgrading by Pressured Water Scrubbing 被引量:1
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作者 HUANG Li JIAO Youzhou +1 位作者 LEI Tingzhou ZHANG Quanguo 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第4期50-55,共6页
Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential ofbiogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization ... Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential ofbiogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization of it is monotonous. The suitable operation term about biogas upgrading by pressurized water scrubbing was researched through the orthogonal test in this study. Two sorts of scrubber packing included the random multidimensional hollow sphere packing and the structured screen packing were also used, and the effects of experiment factors included packing, water temperature, gas flow speed, water flow speed and washing pressure were studied. The results showed that better effect was got when the screen structured packing was used; all the five test factors affected the processing significantly in the arrange as before and had better and better significant effects. 展开更多
关键词 BIOGAS UPGRADING pressured water scrubbing orthogonal test
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Optimization of Ultrasonic Extraction Process of Oenanthe benghalensis Polysaccharide by Orthogonal Test 被引量:1
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作者 Liufu LU Aiyue LUO +6 位作者 Bingyang LIN Zhenlian XIE Guangyu GAN Xiuzhen HUANG Zhidong LEI Shimei CHEN Suoyi HUANG 《Medicinal Plant》 CAS 2018年第5期23-26,共4页
[Objectives] The research aimed to explore extraction method of Oenanthe benghalensis polysaccharide,and determine the optimal process of its ultrasonic extraction by orthogonal test. [Methods] Phenol-sulfuric acid me... [Objectives] The research aimed to explore extraction method of Oenanthe benghalensis polysaccharide,and determine the optimal process of its ultrasonic extraction by orthogonal test. [Methods] Phenol-sulfuric acid method was used to determine polysaccharide's content. Based on single-factor experiment and orthogonal test,the influences of solid-liquid ratio( A),ultrasonic extraction temperature( B),ultrasonic power( C) and ultrasonic time( D) on extraction rate of O. benghalensis polysaccharide were studied,and the optimal process of ultrasonic extraction was selected. [Results] The influence order of solid-liquid ratio( A),ultrasonic extraction temperature( B),ultrasonic power( C) and ultrasonic time( D) on extraction rate of O. benghalensis polysaccharide was A > D > B > C. Via the orthogonal test,it was determined that the optimal extraction condition of O. benghalensis polysaccharide was as below: solid-liquid ratio 1∶ 25( g/mL),extraction temperature 60℃,extraction power 80 W,extraction time 40 min. Under the condition,extraction rate of O. benghalensis polysaccharide was9. 80%. [Conclusions] The process could provide the reference basis for extracting and producing O. benghalensis polysaccharides. 展开更多
关键词 orthogonal test OENANTHE benghalensis POLYSACCHARIDE ULTRASONIC method
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Optimization of Extraction Process of Prunellae Spica Compound by Orthogonal Test 被引量:1
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作者 Dongyan LIAO Jie HUANG Xiaocong MA 《Medicinal Plant》 CAS 2019年第3期60-62,共3页
[Objectives] The study aimed to optimize the extraction process of Prunellae Spica compound to provide an experimental basis for the development and utilization of the compound. [Methods]Through orthogonal test,the op... [Objectives] The study aimed to optimize the extraction process of Prunellae Spica compound to provide an experimental basis for the development and utilization of the compound. [Methods]Through orthogonal test,the optimal extraction process of Prunellae Spica compound was chosen by using the yield of dry paste and ursolic acid content as evaluation indicators. [Results]The optimal extraction process of Prunellae Spica compound is as follows: solvent dosage was 16 times,and extraction frequency was 3 times,while extraction time was 1 h.[Conclusions]The extraction process of Prunellae Spica compound was stable and feasible,and this study can provide a theoretical basis for further preparation of the compound. 展开更多
关键词 orthogonal test Prunellae Spica Ursolic ACID EXTRACTION PROCESS
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Optimization of Extraction Process of Zihua Qinghuo Capsule by Orthogonal Test 被引量:2
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作者 Yan WU Hai ZHAO Maoguo YU 《Agricultural Biotechnology》 CAS 2018年第5期229-231,共3页
With quercetin content and yield of dry extract as investigation indices, three factors, amount of water added, decoction time and decoction times were investigated by an orthogonal test, so as to select the optimal w... With quercetin content and yield of dry extract as investigation indices, three factors, amount of water added, decoction time and decoction times were investigated by an orthogonal test, so as to select the optimal water extraction process for Zihua Qinghuo Capsule. The determined extraction process was adding 8 times of water in five herbs including Viola philippica and decocting for 2 times, 1.5 h each time. Pilot scale test demonstrated that the selected process is stable and feasible, and could provide reliable reference for practical production. 展开更多
关键词 Zihua Qinghuo Capsule Extraction process QUERCETIN orthogonal test
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Study on the insecticidal activities of the extracts from four plants under orthogonal test 被引量:1
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作者 WEN Pu-hong ZHAO Wei-xing WANG Yan ZHAO Yong-chun LI Zong-xiao 《宝鸡文理学院学报(自然科学版)》 CAS 2012年第1期14-16,共3页
Aim To prepare dry powder insecticide by mixing the plant samples of Aconitum ochranthum Mey.,Aconitum hemsleyanum Pritz.and Dictamnus dasycarpus Turcz.Method The dosage ratios of the break stocks from the plants ment... Aim To prepare dry powder insecticide by mixing the plant samples of Aconitum ochranthum Mey.,Aconitum hemsleyanum Pritz.and Dictamnus dasycarpus Turcz.Method The dosage ratios of the break stocks from the plants mentioned above are installed as four factors,and three levels are selected for every factor.The test is actualized according to L 9(3 4) orthogonal array.Results An optimized recipe A 3 B 3 C 3 D 1 has been obtained after considering multifarious factors such as the resources of these plants and the water-solubility of samples.Conclusion The dry powder insecticide prepared by mixing the plant samples mentioned above as 1∶1∶1mass ratio revealed that insecticidal activities for cickets,grasshopper,aphid,and 3rd instar Mythimna separata walker are significant,respectively. 展开更多
关键词 insecticidal activities nature plants orthogonal test
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Orthogonal tests of lead-clad tin bimetal continuous casting by air pressure core-filling 被引量:1
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作者 梁贺 赵永龙 +1 位作者 臧勃林 吴春京 《Journal of Central South University》 SCIE EI CAS 2011年第5期1340-1348,共9页
To provide theoretical basis and practical guidance for preparing composite rods of external diameter no larger than 12 mm by directly continuous casting,low melting point materials of lead and tin were selected to pr... To provide theoretical basis and practical guidance for preparing composite rods of external diameter no larger than 12 mm by directly continuous casting,low melting point materials of lead and tin were selected to prepare composite rods of external diameter 12 mm and inner diameter 8 mm with air pressing core filled continuous casting process.The orthogonal tests consisting of three factors and three levels were designed to investigate the parameters of melting lead temperature,continuous casting speed and air pressure that affect the performance of the composite rods.The results show that melting lead temperature is the most important factor that influences the solid/liquid interface location;continuous casting speed is the most important factor that influences the surface quality and lead and tin inter-diffusion amount;air pressure can improve the surface quality obviously and make the rods easily drawn out,but the surface quality cannot get obvious improvement when the air pressure is above 0.03 MPa.The composite rods have excellent surface quality,obvious intermediate layer,even thick clad,and metallurgical bonding interface under the condition of melting lead temperature of 375 °C,continuous casting speed of 10 mm/min,and air pressure of 0.03 MPa. 展开更多
关键词 空气压力 正交试验 直接连铸 双金属 表面质量 包钢
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Decompositions of Symmetry Using Generalized Linear Diagonals-Parameter Symmetry Model and Orthogonality of Test Statistic for Square Contingency Tables
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作者 Kouji Yamamoto Motoki Ohama Sadao Tomizawa 《Open Journal of Statistics》 2013年第6期9-13,共5页
For square contingency tables with ordered categories, the present paper gives several theorems that the symmetry model holds if and only if the generalized linear diagonals-parameter symmetry model for cell probabili... For square contingency tables with ordered categories, the present paper gives several theorems that the symmetry model holds if and only if the generalized linear diagonals-parameter symmetry model for cell probabilities and for cumulative probabilities and the mean nonequality model of row and column variables hold. It also shows the orthogonality of statistic for testing goodness-of-fit of the symmetry model. An example is given. 展开更多
关键词 umulative Probability Global SYMMETRY LINEAR Diagonals-Parameter SYMMETRY Mean Equality Ordinal Category orthogonal test Statistic
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Optimization of the Ethanol Extraction Method of Monoester Alkaloids from Radix Aconiti Preparata Based on HPLC-MS and Orthogonal Test
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作者 Changkai ZHOU Rui ZHANG +13 位作者 Xiuling SHANG Lihua ZHOU Zukang ZHANG Jing GAO Hongxia YU Hongyan JI Xiaomin XING Qie GUO Donghua LIU Fangang MENG Jingchun YAO Na ZHANG Yongjun LIU Fanbo JING 《Agricultural Biotechnology》 CAS 2020年第3期73-77,共5页
[Objectives] This study was conducted to optimize the ethanol extraction technology of monoester alkaloids from Radix Aconiti Preparata. [Methods]On the basis of defined extraction times,ethanol concentration,ethanol ... [Objectives] This study was conducted to optimize the ethanol extraction technology of monoester alkaloids from Radix Aconiti Preparata. [Methods]On the basis of defined extraction times,ethanol concentration,ethanol times and extraction time were investigated by HPLC-MS combined with orthogonal test to optimize extraction process using the content of monoester alkaloids( the sum of benzoyl neoaconitine,benzoyl hypoaconitine and benzoyl aconitine) as an index.[Results]The optimum ethanol extraction technology was as follows: 75% ethanol,ethanol amount 25 times of the medicinal material,and each extraction for 1. 5 h.[Conclusions] The optimal extraction technology is simple,feasible,stable and reliable. It can provide reference for the industrial production and quality control of monoester alkaloids from Radix Aconiti Preparata. 展开更多
关键词 Radix aconiti preparata monoester alkaloid HPLC-MS orthogonal test
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Research on Treatment of Landfill Leachate Polluting Groundwater by Orthogonal Test
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作者 Shan Changqing Li Jialiang 《Meteorological and Environmental Research》 CAS 2014年第9期53-56,共4页
Through PRB simulated device and orthogonal test,we discussed the treatment effect of groundwater polluted by landfill leachate with three reaction mediums of zero-valent iron powder,activated carbon and zeolite. We c... Through PRB simulated device and orthogonal test,we discussed the treatment effect of groundwater polluted by landfill leachate with three reaction mediums of zero-valent iron powder,activated carbon and zeolite. We considered four factors of iron powder mass,activated carbon mass,particle size of iron powder and zeolite mass,and designed a two-level orthogonal test. It concluded that effluent pH appeared to fall or rise as the reaction proceeded,which changed during 7- 8. The removal rates of CODCrin eight reactors were during 60. 7%- 78. 3%,and the removal rates of NH3-N were during 34. 0%- 58. 8%. Activated carbon mass and the interaction of iron powder mass and activated carbon mass had significant influences on the removal of CODCr,while iron powder mass,particle size of iron powder and zeolite mass had insignificant influences on the removal of CODCr. Zeolite mass and activated carbon mass had significant influences on the removal of NH3,while iron powder mass,particle size of iron powder and the interaction with activated carbon mass had insignificant influences on the removal of NH3-N. 展开更多
关键词 Landfill leachate Groundwater Treatment orthogonal test China
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Test case generation based on orthogonal table for software black-box testing
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作者 刘久富 杨忠 +1 位作者 杨振兴 孙琳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第3期365-368,共4页
Software testing is an important means to assure the software quality. This paper presents a practicable method to generate test cases of software testing, which is operational and high efficient. We discuss the ident... Software testing is an important means to assure the software quality. This paper presents a practicable method to generate test cases of software testing, which is operational and high efficient. We discuss the identification of software specification categories and choices and make a classification tree. Based on the orthogonal array, it is easy to generate test cases. The number of this method is less than that of all combination of the choices. 展开更多
关键词 软件质量 软件可靠性 软件测试 正交阵列
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Warm Compaction Process of P/M Steels by Orthogonal Testing Method
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作者 叶途明 YI Jianhong +2 位作者 PENG Yuandong XIA Qinglin WANG Hongzhong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第1期105-108,共4页
为了用 die 完成 P/M 钢的更高的密度,围在温暖的压缩过程压缩方法或粉末润滑剂的润滑油,温暖的压缩样品的绿密度上的不同过程参数的影响被学习。根据直角的测试方法,作者系统地学习不同压缩压力的影响,润滑油的状况;在温暖的压缩... 为了用 die 完成 P/M 钢的更高的密度,围在温暖的压缩过程压缩方法或粉末润滑剂的润滑油,温暖的压缩样品的绿密度上的不同过程参数的影响被学习。根据直角的测试方法,作者系统地学习不同压缩压力的影响,润滑油的状况;在温暖的压缩过程的样品的绿密度上的压缩温度,;提出温暖的压缩实验的最佳的进程参数。它被发现那,一个高压缩压力(≥ 7 00 MPa ) ,死墙润滑油与内部润滑剂的小数量结合了,;由润滑油的不同状况的恰当的压缩温度,是在温暖的压缩的最佳的参数过程。 展开更多
关键词 粉末冶金钢 热压过程 正交测试方法 模壁润滑
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Influence of Factors on Dechromisation of a Cu-Cr alloy in HCl Solution by Orthogonal Test
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作者 Yan Chen Panpan Zhai +2 位作者 Guirong Peng Jianhua Liu Ruijun Zhang 《材料科学与工程(中英文版)》 2010年第10期56-59,共4页
关键词 盐酸溶液 铜铬合金 正交试验 影响因素 溶液浓度 温度上升 HCI 变形
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STUDIES ON CULTURE CONDITIONS OF BENTHIC DIATOMS FOR FEEDING ABALONE Ⅲ. EFFECTS OF IRON AND SILICON NUTRIENTS AND OF ORTHOGONAL COMBINATIONS OF NITROGEN,PHOSPHORUS,IRON AND SILICON ON GROWTH RATE 被引量:5
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作者 王起华 李雅娟 李梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第2期105-111,共7页
Effects of iron and silicon nutrients and of orthogonal combinations of nitrogen, phosphorus, iron and silicon on the growth rate of three benthic diatoms were studied by using an in situ OD measurement method. The re... Effects of iron and silicon nutrients and of orthogonal combinations of nitrogen, phosphorus, iron and silicon on the growth rate of three benthic diatoms were studied by using an in situ OD measurement method. The results of monofactor tests of ironand silicon shawed that Fe-EDTA was bettef than ferric citrate in the culture of these diatoms;that the favourable concentration of Fe-EDTA was about 0.5 mg/L of Fe and that of silicate was 2.5 mg/L of Si or more.The orthogonal test showed that the optimal concentration ratios(mg/L)of nitrogen, phosphorus, iron and silicon were: 5. 0: 0. 25: 0.5: 2. 0 for Cocconeis scutellum var. parva; 2.5: 1.0: 1.0: 2.0 for Amphora coffeaeformis; and 5.0: 0. 15: 0.5: 2.0 for N. mollis. 展开更多
关键词 BENTHIC diatoms NUTRIENTS orthogonal test growth rate
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Labyrinth Seal Design Optimization Based on Quadratic Regression Orthogonal Experiment 被引量:1
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作者 Lihua Cao Heyong Si +1 位作者 Pan Li Yong Li 《Energy and Power Engineering》 2017年第4期204-215,共12页
The influence of labyrinth seal structure parameters and their interaction on the characteristics of leakage amount are numerically investigated by conducting a quadratic regression orthogonal experiment. To determine... The influence of labyrinth seal structure parameters and their interaction on the characteristics of leakage amount are numerically investigated by conducting a quadratic regression orthogonal experiment. To determine the optimal structure parameters of the steam seal for minimizing the leakage amount, a reliable regression equation that does not lack of fit is established. The flow characteristics of the fluid in the labyrinth seal are analyzed in detail. Results show that the leakage amount is greatly influenced by seal cavity depth, convex platform height, seal tooth thickness, and tooth tip clearance, with the tip clearance having the most significant effect. The interaction among the four items exerts a certain impact on the leakage amount. The proposed regression equation exhibits a good significance and does not lack of fit. After optimization, the labyrinth seal demonstrates increased entropy and energy dissipation at the tip of the seal tooth, as well as decreased speed and inertia effect in the cavity, suggesting that the resistance leakage performance of the optimized labyrinth seal is improved. 展开更多
关键词 LABYRINTH SEAL Structure PARAMETERS Regression orthogonal test LEAKAGE AMOUNT Optimization
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