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EFFECTIVE INDEX PROFILE ALONG THE DEPTH DIRECTION OF Ti∶LiNbO 3 STRIP WAVEGUIDE
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作者 赵慈 胡鸿璋 +1 位作者 詹仰钦 伊晓光 《Transactions of Tianjin University》 EI CAS 1996年第2期79+77-78,共3页
Based on the quasi analytical technique, an analytical expression for the effective index profile in the depth direction in Ti:LiNbO 3 strip waveguide is theoretically derived. It is very u... Based on the quasi analytical technique, an analytical expression for the effective index profile in the depth direction in Ti:LiNbO 3 strip waveguide is theoretically derived. It is very useful for the research into the propagation characteristics of the strip waveguides with metal clad. From this expression, the field distributions and modal indices in typical waveguides are calculated. In addition, the method of how to get the position where the mode field has the maximum value is yielded in this paper. It is very important to the optical coupling between two waveguides or between the waveguide and the fiber. 展开更多
关键词 integrated optics optical waveguide Ti diffusion effective refractive index
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Research on Affordability Modeling of Aircraft Based on Effectiveness Indexes
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作者 YAN Sheng-wen GUO Ji-han 《International Journal of Plant Engineering and Management》 2011年第1期15-20,共6页
With the cost estimation of military aircraft as the research object, this paper aims to study the contradiction between the choice of explanatory variables in index modeling and the maintaining of model validity. It ... With the cost estimation of military aircraft as the research object, this paper aims to study the contradiction between the choice of explanatory variables in index modeling and the maintaining of model validity. It analyzes and establishes a cost estimation modeling concept based on an Effectiveness Index and studies the way to construct Effectiveness Indexes for the sake of cost estimation modeling. Based on a case study, the paper establishes and analyzes the Effectiveness Index-based cost estimation models and DAPCA (Development And Procurement Costs of Aircraft) models developed by the RAND Corparation . The comparison of these models shows that the Effective- ness Index-based cost parameter models not only comprehensively consider the obvious driving parameter indexes of the cost, but reduces the variables of regressive analysis, hence giving the model a higher reliability. 展开更多
关键词 military aircraft effectiveness index AFFORDABILITY COST parameter model
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Automatic Variable Selection for Single-Index Random Effects Models with Longitudinal Data
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作者 Suigen Yang Liugen Xue 《Open Journal of Statistics》 2014年第3期230-237,共8页
We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method share... We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method shares some of the desired features of existing variable selection methods: the resulting estimator enjoys the oracle property;the proposed procedure avoids the convex optimization problem and is flexible and easy to implement. Moreover, we use the penalized weighted deviance criterion for a data-driven choice of the tuning parameters. Simulation studies are carried out to assess the performance of our method, and a real dataset is analyzed for further illustration. 展开更多
关键词 VARIABLE SELECTION Single-index MODEL RANDOM effects Longitudinal DATA
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On the Validity of the Effective Index Method for Long Period Grating Photonic Crystal Fibers
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作者 Dhia Khadri Walid Belhadj +2 位作者 Douha Gamra Fathi AbdelMalek Habib Bouchriha 《Materials Sciences and Applications》 2012年第5期310-316,共7页
This paper focuses on the investigation of modal characteristics and sensing properties of long period grating photonic crystal fibers (LPG-PCFs). An improved effective index method is employed with an objective to st... This paper focuses on the investigation of modal characteristics and sensing properties of long period grating photonic crystal fibers (LPG-PCFs). An improved effective index method is employed with an objective to study its limitations for various designs of LPG-PCFs. Results so obtained with the above method are compared with the corresponding values of multiple multipole (MMP) method results which points the range of validity and applicability of the improved effective index method to LPG-PCFs. It is shown that this method is excellent when the surrounding media is assumed to be air. However, it becomes less accurate when the fiber is immersed into a liquid with a refractive index close to that of the cladding. 展开更多
关键词 Long Period GRATINGS Photonic Crystal Fiber (LPG-PCF) Improved effective index MMP CLADDING Modes Sensor Sensitivity
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Effects of leaf N concentration and leaf area index on determining rice tillering
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《Chinese Rice Research Newsletter》 1999年第4期8-9,共2页
Relative tillering rate(RTR)increased linear-ly with the increasing of leaf N concentration(NLV)has been already reported.To testwhether this relationship could be used toquantitatively explain the difference in tille... Relative tillering rate(RTR)increased linear-ly with the increasing of leaf N concentration(NLV)has been already reported.To testwhether this relationship could be used toquantitatively explain the difference in tilleringamong a wide range of N application,field ex- periments were conducted at the IRRI farm,Los Banos,Laguna,the Philippines.Two in- dica cultivars,IR 72 and IR68284H wereused.For each cultivar,12 treatments includ- ing 4 N levels(0,60,120,and 180kgN·ha)and 3 transplanting spacing(30×20,20×20,and 10×20cm)were arranged in a ran-domized split-plot design with 4 replications.The N treatments were designated as mainplots and spacings as subplots.Fourteen-day-old seedlings were transplanted with 3seedlings per hill.The subplot area was 20m~2.Nitrogen fertilizer was applied as basal,atmidtillering,and at panicle initiation in threeequal splits.P,K,and Zn were applied asbasal at normal dosage.The field was flooded.Plant samples were taken every 7-14 d from 14d after transplanting to flower 展开更多
关键词 area IR effects of leaf N concentration and leaf area index on determining rice tillering
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Effect of Alligator Pepper on Litter Weight of Rats Fed on High Glycemic Index Diet
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作者 Ute Inegbenebor Festus Eghomwanre 《Food and Nutrition Sciences》 2017年第8期793-800,共8页
This study was carried out to find out if alligator pepper can prevent the development of fetal macrosomia in Sprague-Dawley rats fed with high glycemic index diet. Fifteen adult female Sprague-Dawley rats of proven f... This study was carried out to find out if alligator pepper can prevent the development of fetal macrosomia in Sprague-Dawley rats fed with high glycemic index diet. Fifteen adult female Sprague-Dawley rats of proven fertility were acclimatized for a period of two weeks in a well-ventilated laboratory and fed with grower’s mash and water ad libitum. Thereafter, they were randomly placed in separate cages after which a male Sprague-Dawley rat of proven fertility was introduced into each of the cages containing the female rats. They were left in the cages for three days during, which mating was confirmed to have occurred. The male rats were then withdrawn from the female rats, which were placed in separate maternity cages. The female rats were randomly allocated to three groups A, B and C so there were 5 pregnant rats in each group. The rats in group A were fed with 50 g of grower’s mash daily while the rats in groups B and C were fed with 50 g of cooked fermented cassava respectively. All rats were given water ad libitum throughout the duration of the experiment. The rats in groups A and B were intraperitoneally injected with 13.3 ml per Kg body weight of distilled water while the rats in group C were intraperitoneally injected with 13.3 mg/Kg body weight of aqueous extract of alligator pepper respectively. They were observed for 18 - 25 days. The litters of the rats in group B had a significantly higher mean weight than the rats in group A while the litters of the rats in group C had a significantly lower mean weight than the rats in groups B. It was concluded that intraperitoneally injected aqueous extract of alligator pepper, in the first trimester of pregnancy, can prevent the development of fetal macrosomia in Sprague-Dawley rats. 展开更多
关键词 effect ALLIGATOR PEPPER HIGH Glycemic index DIET LITTER Weight Sprague Dawley Rat
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Study on Multi-effect Time Parameters of Ergonomic Validity Index in Low-carbon Residential Kitchen
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作者 Jun Ji Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期52-58,共7页
In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts... In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation. 展开更多
关键词 functional low-carbon human factors ergonomic validity index basal heart rate increment ratio multi-effect time of kitchen work
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Simulation on Distribution of Photosynthetically Active Radiation in Canopy and Optimum Leaf Rolling Index in Rice with Rolling Leaves 被引量:3
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作者 Hu Ning Lu Chuan-gen +1 位作者 YAO Ke-min Zou Jiang-shi 《Rice science》 SCIE 2009年第3期217-225,共9页
By replacing leaf area index (LAI) with effective leaf area index (ELAI) through introduction of leaf rolling index (LRI), the distributions of photosynthetically active radiation (PAR) in the canopies of thre... By replacing leaf area index (LAI) with effective leaf area index (ELAI) through introduction of leaf rolling index (LRI), the distributions of photosynthetically active radiation (PAR) in the canopies of three hybrid rice combinations, Liangyou E32 with high LRI, Liangyoupeijiu with moderate LRI and Shanyou 63 with non-rolling leaves (normal), were simulated. The model based on ELAI could predict more accurately than that based on LAI. The PAR interception, conversion and utilization efficiency in the three combinations were studied to evaluate their optimal LRI and LAI. The PAR utilization efficiency of Liangyou E32 was lower due to excessive rolling leaves and less ELAI, and that of Shanyou 63 was also lower because of the faulty PAR interception and lower photosynthetic rate and saturation point at lower layer in canopy. Compared with the above two combinations, Liangyoupeijiu showed more appropriate distribution of PAR interception and conversion efficiency in canopy, and higher PAR utilization efficiency. The optimal LRI and LAI for Liangyoupeijiu were 0.11 and 7.6, respectively, which were close to the observed value, 0.11 and 7.9, respectively. However, the optimum LAI was 9.8 for Liangyou E32 and 6.2 for Shanyou 63, larger or smaller than those under the current plant density, which led to lower efficiency of PAR utilization. Besides, the optimum LRI for Liangyou E32 and Shanyou 63 were 0.12 and 0.08, respectively, which were close to the actual LRI for Liangyoupeijiu (0.11). 展开更多
关键词 RICE leaf rolling index effective leaf area index photosynthetically active radiation utilization efficiency population density
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Enthalpies Estimation of Formation of Monosubstituted Alkanes by Interaction Potential Index 被引量:3
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作者 Ya-xin Wu Chen-zhong Cao Hua Yuan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期153-160,I0003,共9页
The interaction potential index IPI(X) of 16 Br, C1, I, NO2, CN, CHO, COOH, CH3, CH: kinds of substituents X (X---OH, SH, NH2, :CH2, C-CH, Ph, COCH3, COOCH3) were proposed, which are derived from the experimenta... The interaction potential index IPI(X) of 16 Br, C1, I, NO2, CN, CHO, COOH, CH3, CH: kinds of substituents X (X---OH, SH, NH2, :CH2, C-CH, Ph, COCH3, COOCH3) were proposed, which are derived from the experimental enthalpies of formation △fHФ (g) values of monosubstituted straight-chain alkanes. Based on the IPI(X) and polarizability effect index, a simple and effective model was constructed to estimate the △fHФ (g) values of monosubstituted alkanes RX (including the branched derivatives). The present model takes into account not only the contributions of the alkyl R and the substituent X, but also the contribution of the interaction between R and X. Its stability and prediction ability was confirmed by the results of leave-one-out method. Compared with previous reported studies, the obtained equation can be used to estimate enthalpies of formation for much more kinds of monosubstituted alkanes with less parameters. Thus, it is recommended for the calculation of the △fHФ(g) for the RX. 展开更多
关键词 Interaction potential index SUBSTITUENT Monosubstituted alkane Enthalpy offormation Polarizability effect index
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Oasis cold island effect and its influence on air temperature: a case study of Tarim Basin, Northwest China 被引量:2
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作者 HAO Xingming LI Weihong 《Journal of Arid Land》 SCIE CSCD 2016年第2期172-183,共12页
Oasis effect can improve the regional climate and habitability of an arid region. In this study, we explored the cold island effects of oases distributed along the edge of Tarim Basin by analyzing the oasis cold islan... Oasis effect can improve the regional climate and habitability of an arid region. In this study, we explored the cold island effects of oases distributed along the edge of Tarim Basin by analyzing the oasis cold island effect (OCIE) intensity, spatial-temporal variation of OCIE, factors influencing the OCIE and impacts of OCIE on air temperature using geographical statistics and GIS methods based on the MODIS land surface temperature, land use/cover change (LUCC) and observed air temperature data. Results showed that all the oases in the Tarim Basin exhibited cold island effects, with the OCIE intensity highest in summer (-9.08℃), followed by autumn (-4.24℃) and spring (-3.85℃). The total area of oasis cold island (OCI) and the comprehensive OCIE index showed the same seasonal change trend as the OCIE intensity. However, the changing trends in areas of OCI with strong, medium and weak OCIEs were inconsistent across different seasons. Farmland and water areas were found to be the key contributors that affected the OCIE, and the area and aggregation metrics of these two land use/cover types directly contributed to the OCIE. By contrast, natural vegetation, such as forest and grassland, almost had no contribution to the OCIE. Simulation of observed air temperature data showed that if farmland is replaced by forest or grassland in the oasis, the mean, maximum and minimum air temperatures will increase significantly. This heating effect will be higher in summer (reaching 1.14℃ to 2.08℃) and lower in spring and autumn. Moreover, the heating effect of farmland being replaced by forest will be higher than that of farmland being replaced by grassland. These results can provide a basis for understanding the cold island effect of oases in arid regions. 展开更多
关键词 oasis cold island effect comprehensive oasis cold island effect index landscape index oasis evolution arid environment
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Spectrum-Effect Relationship Between High Performance Liquid Chromatography Fingerprints and Anticoccidial Activities of a Compound Chinese Medicine 被引量:5
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作者 XIAO Sui FEI Chen-zhong +3 位作者 ZHANG Li-fang ZHENG Wen-li ZHANG Ke-yu XUE Fei-qun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第5期1082-1089,共8页
Quality control and screening of active substances in traditional Chinese medicines have been performed using fingerprint analysis. The spectrum-effect relationship between chromatography fingerprints and efficacy of ... Quality control and screening of active substances in traditional Chinese medicines have been performed using fingerprint analysis. The spectrum-effect relationship between chromatography fingerprints and efficacy of herbal drugs is considered as a potentially useful method for determining active ingredients in complex mixtures. The study was designed to develop a method for determining the bioactive components of a compound Chinese medicine called Tiefeng based on spectrum-effect relationships between high-performance liquid chromatography (HPLC) fingerprints and anticoccidial activities. Four peaks of the established HPLC fingerprint indicate the main bioactive components of this medicine. In addition, pharrnacodynamic atlas was defined and used to assess the anticoccidial activity of Tiefeng from different sources for the first time. We found that the level of anticoccidial activity of Tiefeng was consistent with the degree of similarity between the pharmacodynamic atlas and chromatogram of any sample. Furthermore, effect of this medicine was related with the main active constituents, along with the origin and the harvesting time. 展开更多
关键词 herb medicine FINGERPRINT anticoccidial index spectrum-effect relationship
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Optical Absorption Enhancement Effects of Silver Nanodisk Arrays in the Application of Silicon Solar Cell 被引量:1
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作者 Xiao-Ping Huang Zao-Jin Zeng Lei Zhong Dan Wu Fang-Chun Yan 《Journal of Electronic Science and Technology》 CAS 2011年第1期35-40,共6页
Surface plasmon resonance of noble metal nanoparticles leads to the optical absorption enhancement effects,which have great potential applications in solar cell.By using the general numerical method of discrete dipole... Surface plasmon resonance of noble metal nanoparticles leads to the optical absorption enhancement effects,which have great potential applications in solar cell.By using the general numerical method of discrete dipole approximation (DDA),we study the absorption and scattering properties of two-dimensional square silver nanodisks (2D SSN) arrays on the single crystal silicon solar cell.Based on the effective reflective index model of the single crystal silicon solar cell,we investigate the optical enhancement absorption of light energy by varying the light incident direction,particle size,aspect ratio,and interparticle spacing of the silver nanodisks.The peak values and position of the optical extinction spectra of the 2D square arrays of noble metal nanodisks are obtained with the different array structures. 展开更多
关键词 effective reflective index model optical absorption enhancement effects silicon solar cell two-dimensional square silver nanodisks arrays.
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Particulate Matter-Based Air Quality Index Estimate for Abuja, Nigeria: Implications for Health 被引量:2
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作者 Rogers Bariture Kanee Adewale Adeyemi +1 位作者 David Onojiede Edokpa Precious Nwobidi Ede 《Journal of Geoscience and Environment Protection》 2020年第5期313-321,共9页
In recent years, urban air quality in developing countries such as Nigeria has continued to degenerate and this has constituted a major environmental risk to human health. It has been shown that an increase in ambient... In recent years, urban air quality in developing countries such as Nigeria has continued to degenerate and this has constituted a major environmental risk to human health. It has been shown that an increase in ambient particulate matter (PM10) load of 10 μg/m3 reduces life expectancy by 0.64 years. Air Quality Index (AQI) as demonstrated in this study shows how relatively clean or polluted the boundary layer environment of any location can be. The study was designed to measure the level of suspended particulate matter (PM2.5 and PM10) for dry and wet seasons, compute the prevalent air quality index of selected locations in Abuja with possible health implications. Suspended particulate matter (PM2.5 and PM10) was assessed using handheld aerosol particulate sampler. The US Oak Ridge National AQI was adopted for the eleven (11) locations sampled and monitored. The study results showed that the air quality of the selected areas in Abuja were generally good and healthy. Dry season, assessments, showed 15 - 95 μg/m3 and 12 - 80 μg/m3 for PM2.5 and PM10, respectively. While in wet season, 09 - 75 μg/m3 and 07 - 65 μg/m3 were recorded for PM2.5 and PM10. However at Jebi Central Motor Park, there was light air contamination with AQI of 42 for dry season and 31 for wet season. Other locations had clean air with AQI ≤ 11. It is revealed that clean air exists generally during the wet season. Comparing study outcome to other cities in Nigeria, residents of Abuja are likely not to be affected with health hazards of particulate matter pollution. Nonetheless, the high range of PM2.5 and PM10 (fine and coarse particles) ratio evaluated i.e., 1.06 - 1.79 was higher than the WHO recommended standard of 0.5 - 0.8. This ratio remains a health concerns for sensitive inhabitants like pregnant women and their foetus as well as infants below age five whose respiratory airways are noted to have high surface areas and absorption capacity for fine particulate matter. Vegetation known to absorb suspended particulate matter should be planted across Abuja metropolitan areas and air quality monitoring stations installed at strategic locations for continuous monitoring and evaluations. 展开更多
关键词 AIR Pollution PARTICULATE MATTER AIR Quality index Abuja HEALTH effects
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Effect and Mechanism Analysis of Solvent on the Electron Transition of Fluoroquinolones Based on Quantum Chemical Calculation 被引量:1
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作者 陈凤先 海热提 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第12期1931-1946,共16页
Ciprofloxacin(CIP), moxifoxacin(MOX) and enrofloxacin(ENR) were selected as typical fluoroquinolones(FQs) to analyze the excitation-enhancing effect and mechanism of solvents on FQs' electron transition based... Ciprofloxacin(CIP), moxifoxacin(MOX) and enrofloxacin(ENR) were selected as typical fluoroquinolones(FQs) to analyze the excitation-enhancing effect and mechanism of solvents on FQs' electron transition based on quantum chemical calculations. The UV spectra of three FQs in gas and five different solvents(water, cyclohexane, dimethylsulfoxide, methanol, acetone) were calculated using Gaussian 09 software. The transition mechanisms of FQs' main electron transitions were analyzed by natural bond orbital(NBO) theory, and the solvent effect on each electron transition was assessed qualitatively and quantitatively by sensitivity analysis and an established index system. The excitation enhancing mechanism of solvent on electron transitions of FQs was analyzed from the view of photo-induced reactions between solvent and FQs molecules. The results show that there are two main transitions located in the spectrum ranges of 300~380 and 240~300 nm for each FQ in any medium, which are assigned as n →π* and π→π* electron transitions, respectively. By comparison, the n →π* transition is more sensitive to solvent because of the energy transfer between solvent molecules and FQs, but the solvent effect on the π→π* transition is stronger than on the n →π* transition. The sequence of affected extent of solvent effect on electron transition was CIP 〉 MOX 〉 ENR, and the sequence of solvent effect was water 〉 DMSO 〉 methanol 〉 acetone 〉 cyclohexane(stronger solvent effect with increasing the dielectric constant of solvent). From the view of photo-induced reactions, the reaction between FQs*T1 and solvent*T1 has the decisive regulatory effect on the n →π* transition of FQs in solvent, and the reaction between FQsS0 and solvent*TI has an enhancing effect on the π→π* transition. 展开更多
关键词 FLUOROQUINOLONES electron transition solvent effect index system photo-induced reaction
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AIRCRAFT CONCEPT EVALUATION AND EFFECTIVENESS-BASED DECISION-MAKING 被引量:2
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作者 赵锁珠 杨伟 +1 位作者 李军 刘纪福 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第1期8-16,共9页
Based on effectiveness analysis , a novel method is presented for combat aircraft top-hierarchy concept evaluation and decision-making. Applying multi-criterion decision-making ( MCDM ) and analytic hierarchy process ... Based on effectiveness analysis , a novel method is presented for combat aircraft top-hierarchy concept evaluation and decision-making. Applying multi-criterion decision-making ( MCDM ) and analytic hierarchy process , the new method can help to overcome the limitations of existing evaluation systems and decision-make methods.The proposed method includes the following process :( 1 ) Establish a multi-criterion and multi-hierarchy evaluation attribute system by introducing combat effectiveness ;( 2 ) Assign weight to the attributes and normalize them ;( 3 ) Evaluate and decision-make top-hierarchy aircraft concept based on effectiveness to reach a satisfactory design by comprehensively applying four multi-criterion decision-making methodologies , i.e.grey correlation projection method , weighted summation method , weighted quadrature method and ideal solution decision-making method , while considering the attribute hierarchy system and the logical relations among the attributes.Finally , an example is given to indicate the validity and feasibility of the proposed method. 展开更多
关键词 combat aircraft effectIVENESS evaluation index system multi-criterion decision-making
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Design of an Index System for Deep Groundwater Management Efficiency Evaluation: A Case Study in Tianjin City, China 被引量:1
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作者 NAN Tian SHAO Jingli +2 位作者 CAO Xiaoyuan ZHANG Qiulan CUI Yali 《Chinese Geographical Science》 SCIE CSCD 2016年第3期325-338,共14页
An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index s... An effective evaluation system can provide specific and practical suggestions to the deep groundwater management. But such kind of evaluation system has not been proposed in China. In this study, an evaluation index system is specifically developed to evaluate deep groundwater management efficiency. It is composed of three first-level indicators(law enforcement capability, management ability, and management effectiveness) and eleven second-level indicators. The second-level indicators include seven mandatory indicators and four optional indicators. Piecewise linear function is used to normalize the quantitative indicators, and expert scoring method and questionnaire survey method are used to normalize the qualitative indicators. Then a comprehensive indicator weighting evaluation method is used to evaluate the first-level indicators and the target topic. A case study is carried out to evaluate deep groundwater management efficiency in Tianjin City. According to the evaluation score in each period, the management efficiency of every district in Tianjin City gradually improved. The overall evaluation score in the early deep groundwater extraction period is 0.12. After a series of deep groundwater protection efforts, this score reached to 0.61 in 2007, and met the regulation criteria. The evaluation results also showed that the further groundwater management efforts in Tianjin City should be focused on building a dynamic database to collect comprehensive deep well-log data; and on a reasonable design and distribution of the groundwater monitoring network. It demonstrated that the index system is suitable to locate the deficiencies of current groundwater management systems and to guide further improvements. It can then be used to protect deep groundwater. 展开更多
关键词 deep groundwater management evaluation index system law enforcement capability management ability management effectiveness
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Effect of Mathematical Expression of Vegetation Indices on the Estimation of Phenology Trends from Satellite Data 被引量:1
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作者 ZUO Lu LIU Ronggao +1 位作者 LIU Yang SHANG Rong 《Chinese Geographical Science》 SCIE CSCD 2019年第5期756-767,共12页
Vegetation indices(VIs) from satellite remote sensing have been extensively applied to analyze the trends of vegetation phenology. In this paper, the NDVI(normalized difference vegetation index) and SR(simple ration),... Vegetation indices(VIs) from satellite remote sensing have been extensively applied to analyze the trends of vegetation phenology. In this paper, the NDVI(normalized difference vegetation index) and SR(simple ration), which are calculated from the same spectral bands of MODIS data with different mathematical expressions, were used to extract the start date(SOS) and end date(EOS) of the growing season in northern China and Mongolia from 2000 to 2015. The results show that different vegetation indices would lead to differences in vegetation phenology especially in their trends. The mean SOS from NDVI is 15.5 d earlier than that from SR, and the mean EOS from NDVI is 13.4 d later than that from SR. It should be noted that 16.3% of SOS and 17.2% of EOS derived from NDVI and SR exhibit opposite trends. The phenology dates and trends from NDVI are also inconsistent with those of SR among various vegetation types. These differences based on different mathematical expressions in NDVI and SR result from different resistances to noise and sensitivities to spectral signal at different stage of growing season. NDVI is prone to be effected more by low noise and is less sensitive to dense vegetation. While SR is affected more by high noise and is less sensitive to sparse vegetation. Therefore, vegetation indices are one of the uncertainty sources of remote sensing-based phenology, and appropriate indices should be used to detect vegetation phenology for different growth stages and estimate phenology trends. 展开更多
关键词 VEGETATION PHENOLOGY VEGETATION index TREND CONSISTENCY noise effect spatially temporal comparability NORTHERN China Mongolia
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老年营养风险指数对腹膜透析相关性腹膜炎患者治疗效果的评估价值 被引量:1
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作者 于龙丽 隋小妮 李垟 《中国血液净化》 CSCD 2024年第7期520-523,共4页
目的探讨老年营养风险指数(geriatric nutritional risk index,GNRI)对腹膜透析相关性腹膜炎(peritoneal dialysis associated peritonitis,PDAP)患者治疗效果的评估价值。方法选取2020年1月—2023年1月于青岛市市立医院就诊的PDAP患者... 目的探讨老年营养风险指数(geriatric nutritional risk index,GNRI)对腹膜透析相关性腹膜炎(peritoneal dialysis associated peritonitis,PDAP)患者治疗效果的评估价值。方法选取2020年1月—2023年1月于青岛市市立医院就诊的PDAP患者147例作为研究对象,根据患者治疗效果分为治愈组和治疗失败组,比较2组间GNRI分值及临床特征差异,分析GNRI分值与PDAP患者治疗效果的关系。结果治愈组患者102例,治疗失败组患者45例,其中患者死亡25例、拔管10例、转院治疗10例。与治愈组相比,治疗失败组患者GNRI分值、体质量指数、血红蛋白、白蛋白(ALB)降低(t=5.134、7.517、2.336、3.259,P<0.001、<0.001、0.021、0.001),透析龄高于治愈组(t=10.924,P<0.001)。Logistic多因素回归分析显示GNRI分值下降(OR=0.541,95%CI:0.335~0.872,P<0.001)、ALB下降(OR=0.638,95%CI:0.494~0.825,P<0.001)和透析龄延长(OR=1.674,95%CI:1.081~2.591,P<0.001)是PDAP患者治疗失败的独立危险预测因素。ROC曲线分析显示GNRI分值预测PDAP患者治疗失败的ROC曲线下面积为0.735,敏感度为89.55%,特异度为75.43%,约登指数为0.649,最佳预测值为90.53分。结论GNRI分值下降是PDAP患者治疗失败的独立危险预测因素,且对PDAP患者治疗失败具有较高的预测效能,及早纠正患者营养状态可改善患者治疗效果。 展开更多
关键词 腹膜透析相关性腹膜炎 老年营养风险指数 治疗效果 危险因素
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The Mathematical Analysis on the Risk Management Effect of Crop Insurance Plan
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作者 Youzhi Liu 《Chinese Business Review》 2003年第2期68-71,共4页
As a variant index, variation has an inherent shortcoming that it can only reflect the static fluctuation of the crop. This paper makes complementary analysis about it on the basis of the comment on Miranda's approac... As a variant index, variation has an inherent shortcoming that it can only reflect the static fluctuation of the crop. This paper makes complementary analysis about it on the basis of the comment on Miranda's approach of β index and goes on to analyze the β index approach under the condition of three kinds of crop insurance plans, β index approach has the advantage that it can dynamically reflect the risk transfer effect of crop insurance plan. At the same insurance level, the smaller the β index is, the better the corresponding risk transfer effect of crop insurance plan is; And vice versa. 展开更多
关键词 crop insurance plan β index approach risk transfer effect
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Quantitative Study on the Templating Effect in the Formation of ZSM-5 Molecular Sieve
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作者 Song Tianyou and Xu Ruren (Department of Chemistry, Jilin University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期391-393,共3页
Since the discovery of ZSM-5 molecular sieves as a promising catalyst material, the synthesis of ZSM-5 has been investigated in great detail. In the first synthesis of ZSM-5,tetrapropylammonium(TPA) was used as the te... Since the discovery of ZSM-5 molecular sieves as a promising catalyst material, the synthesis of ZSM-5 has been investigated in great detail. In the first synthesis of ZSM-5,tetrapropylammonium(TPA) was used as the templating agent. However, the industrial manufacture and application of ZSM-5 molecular sieves arc limited because TPA, the templating agent, is expensive. In the attempt to search for a suitable substitute for TPA, 展开更多
关键词 ZSM-5 Templating effect Templating index
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