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Identification of an Aux/IAA regulator for flesh firmness using combined GWAS and bulked segregant RNA-Seq analysis in watermelon 被引量:1
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作者 Muhammad Anees Hongju Zhu +8 位作者 Muhammad Jawad Umer Chengsheng Gong Pingli Yuan Xuqiang Lu Nan He Mohamed Omar Kaseb Dongdong Yang Yong Zhao Wenge Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第5期1198-1213,共16页
Watermelon is a highly cultivated fruit crop renowned for its quality properties of fruit flesh.Among various quality factors,fruit flesh firmness is a crucial quality parameter influencing the fruit texture,shelf lif... Watermelon is a highly cultivated fruit crop renowned for its quality properties of fruit flesh.Among various quality factors,fruit flesh firmness is a crucial quality parameter influencing the fruit texture,shelf life and its commercial value.The auxin/indole-3-acetic acid(Aux/IAA)plays a significant role in fruit development and ripening of non-climacteric fruits.However,the regulatory mechanism of Aux/IAA in controlling fruit flesh firmness and ripening in watermelon remains unknown.In this study,we employed an integrative approach combining genome-wide association study(GWAS)and bulked segregant RNA-Seq analysis(BSR-Seq)to identify an overlapping candidate region between 12776310 and 12968331 bp on chromosome 6,underlying an auxin-responsive gene(Aux/IAA)associated with flesh firmness in watermelon.Transcriptome analysis,followed by real-time quantitative reverse transcription PCR(qRT-PCR),confirmed that the expression of Aux/IAA was consistently higher in fruits with high flesh firmness.The sequence alignment revealed a single base mutation in the coding region of Aux/IAA.Furthermore,the concomitant Kompetitive/Competitive allele-specific PCR(KASP)genotyping data sets for F2 population and germplasm accessions identified Aux/IAA as a strong candidate gene associated with flesh firmness.Aux/IAA was enriched in the plant hormone signal transduction pathway,involving cell enlargement and leading to low flesh firmness.We determined the higher accumulation of abscisic acid(ABA)in fruits with low flesh firmness than hard flesh.Moreover,overexpression of Aux/IAA induced higher flesh firmness with an increased number of fruit flesh cells while reducing ABA content and flesh cell sizes.Additionally,the allelic variation in Aux/IAA for soft flesh firmness was found to exist in Citrullus mucosospermus and gradually fixed into Citrullus lanatus during domestication,indicating that soft flesh firmness was a domesticated trait.These findings significantly enhanced our understanding of watermelon fruit flesh firmness and consequently the watermelon fruit quality. 展开更多
关键词 WATERMELON Flesh firmness GWAS BSR-Seq KASP marker analysis Transient overexpression
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Innovation and Firm Co-ownership Network in China’s Electric Vehicle Industry
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作者 JIN Zerun ZHU Shengjun 《Chinese Geographical Science》 SCIE CSCD 2024年第2期195-209,共15页
Firms are embedded in complex networks,where diverse ideas combine and generate new ideas.Shareholders of firms are of-ten seen as critical external resources that have significant influence on firm innovation.The cur... Firms are embedded in complex networks,where diverse ideas combine and generate new ideas.Shareholders of firms are of-ten seen as critical external resources that have significant influence on firm innovation.The current literature tends to focus on the rela-tionship between firms and their shareholders,while paying less attention to the connections between firms with the same shareholders.This article identifies two types of network spillover effects,intra-city network effect and inter-city network effect,by visualizing the co-ownership networks in China’s electric vehicle(EV)industry.We find that firms with the same shareholders,which are defined as co-owned EV firms,are more innovative than non-co-owned ones.Furthermore,there are two dominant types of firm co-ownership ties formed by corporate and financial institution shareholders.While corporate shareholders help exploiting local tacit knowledge,financial institutions are more active in bridging inter-city connections.The conclusion is confirmed at both firm and city levels.This paper theor-izes the firm co-ownership network as a new form of institutional proximity and tested the result empirically.For policy consideration,we have emphasized the importance of building formal or informal inter-firm network,and the government should further enhance the knowledge flow channel by institutional construction. 展开更多
关键词 firm co-ownership intra-city network inter-city network technological innovation electric vehicle China
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GHG Emissions of Italian Unlisted Firms and Bank Debt
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作者 Oscar Domenichelli 《Journal of Modern Accounting and Auditing》 2024年第4期190-196,共7页
In this paper I investigate the effect of the greenhouse gas emissions of a sample of 478 Italian unlisted firms on their bank debt,in the context of the growing attention and awareness for climate change issue.My fin... In this paper I investigate the effect of the greenhouse gas emissions of a sample of 478 Italian unlisted firms on their bank debt,in the context of the growing attention and awareness for climate change issue.My findings show that unlisted firms generating low levels of greenhouse gas emissions borrow less long-term,short term,and total bank debt than unlisted firms generating high levels of greenhouse gas emissions,to finance their growth opportunities.Being the first work analyzing this topic,to the best of my knowledge,further empirical research could also investigate the impact of greenhouse gas emissions on the bank financing of unlisted firms of different countries,representing specific cultural and political approaches towards climate change problems. 展开更多
关键词 greenhouse gas emissions greenhouse gas footprint Italian unlisted firms bank debt
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Variation and Probability Grading of Fruit Firmness in Peach Germplasm Resource 被引量:4
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作者 马之胜 王越辉 +2 位作者 贾云云 宣立锋 王建学 《Agricultural Science & Technology》 CAS 2009年第6期91-93,共3页
Objective The aim was to provide basis for further studies on fruit firmness in peach fruits and the standardization and standardization of peach germplasm resource. [ Method] The analysis of fruit firmness of peach g... Objective The aim was to provide basis for further studies on fruit firmness in peach fruits and the standardization and standardization of peach germplasm resource. [ Method] The analysis of fruit firmness of peach germplasm resource was based on the improved firmness measurement, and the probability grading of characteristics was carried out on peach fruit firmness. [Result] The coefficient of variation of peach fruit firmness with skin was less than that of fruit firmness without skin; the fruit firmness with skin and fruit firmness without skin were both fitted the normal distribution; the probability grading of characteristics were divided into five series based on four points of (X-1. 281 8s), (X-0. 524 6s), (X+0. 524 6s) and (X+1.281 8s), so that the probability of 1 -5 were 10%, 20%, 40%, 20% and 10%. [Conclusion] There was more abundant genetic basis in fruit firmness, which held a potential for greater choice. 展开更多
关键词 Peach germplasm Fruit firmness VARIATION Probability grading
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Study on Inheritance Mechanism of Tomato Fruit Firmness 被引量:4
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作者 郭军 郑佳秋 +3 位作者 祖艳侠 吴永成 梅燚 周春霖 《Agricultural Science & Technology》 CAS 2013年第8期1109-1111,1121,共4页
[Objective] This study aimed to investigate the inheritance mechanism of tomato fruit firmness.[Method] Two tomato cultivars significantly different in fruit firmness were selected for investigation of the inheritance... [Objective] This study aimed to investigate the inheritance mechanism of tomato fruit firmness.[Method] Two tomato cultivars significantly different in fruit firmness were selected for investigation of the inheritance mechanism of tomato fruit firmness using combination analysis of six generations (P1,P2,F1,F2,B1 and B2).[Result] The results indicated that the heredity of tomato fruit firmness was consistent with the additive-dominant model controlled by one pair of major genes; the additive effect (d),dominant effect (h) and degree of dominance (h/d) of major genes were 17.37,-7.96 and-0.46,respectively,showing positive additive effect and incompletely dominant-negative effect; the hereditability of major gene effect in B1,B2 and F2 generation was 88.59%,45.81% and 85.62%,respectively.[Conclusion] The heredity of fruit firmness was controlled by one pair of major gene,showing significant additive effect and dominant effect. 展开更多
关键词 Tomato (Lycopersicom esculentum Mill) firmNESS . Mixed major-geneand polygene inheritance
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Absorptive capacity and R&D strategy of labor-managed firms 被引量:1
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作者 罗建利 仲伟俊 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期413-418,共6页
Taking absorptive capacity effects on research spillovers into consideration, this paper focuses on the R&D investment decisions and the output decisions of labor-managed firms. Based on the general model of the cost... Taking absorptive capacity effects on research spillovers into consideration, this paper focuses on the R&D investment decisions and the output decisions of labor-managed firms. Based on the general model of the cost-reducing R&D, the strategic interactions of output and R&D investment between labor-managed firms in a duopoly are analyzed. Moreover, the impact of absorptive capacity effects on optimal output in the production stage is discussed. In the R&D stage, the impacts of absorptive capacity effects on the equilibrium R&D investment in cooperative and non-cooperative R&D are analyzed. Finally, the R&D strategy of labor-managed firms is compared with the behavior of profit-maximizing firms. The results show that equilibrium R&D investment is always higher than that in the exogenous spillover rate, which is similar to the behavior of the profit-maximizing firms. However, unlike the profit-maximizing firms, the impact of the absorptive capacity that affects the relationship between the optimal output and its own(rival' s)R&D is shown to be dependent upon a return-to-scale of the production. 展开更多
关键词 absorptive capacity labor-managed firm R&D strategic interaction
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Security investment and information sharing for complementary firms with heterogeneous monetary loss
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作者 蔡传晰 梅姝娥 仲伟俊 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期241-248,共8页
Two complementary firms' information sharing and security investment are investigated. When two complementary firms with heterogeneous assets are both breached, it is assumed that they suffer different losses which a... Two complementary firms' information sharing and security investment are investigated. When two complementary firms with heterogeneous assets are both breached, it is assumed that they suffer different losses which are associated with their information assets. Some insights about optimal strategies for the firms and the attacker are obtained by the game theory, which forms a comparison with those derived from substitutable firms, and those derived from complementary firms with homogenous loss. In addition, both the unit transform cost of investment and the extent of firms'loss affect the optimal strategies.Assuming that firms can control information sharing, security investments and both of them, respectively, the effect of the social planner is further analyzed on the information sharing, firms' aggregate defence, the aggregate attack and social total cost. Finally, some policy advice is provided through numerical simulation. Results show that firms are willing to choose security investment centrally rather than individually, but an intervention in information sharing by the social planner may not necessarily be preferable. 展开更多
关键词 complementary firm contest success function security investment information sharing leakage cost
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R&D subsidy policy of domestic firm considering foreign firm competition
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作者 张伟 仲伟俊 梅姝娥 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期513-519,共7页
Taking the advanced technology of the foreign firm into account, a mixed duopoly three-stage game model is established in the context of research and development(RD)investment subsidies and product subsidies for dom... Taking the advanced technology of the foreign firm into account, a mixed duopoly three-stage game model is established in the context of research and development(RD)investment subsidies and product subsidies for domestic firms provided by the government, and the RD subsidy policy of domestic firms in competition with foreign firms is analyzed.The equilibrium output, RD investment of the domestic firm, social welfare and the value of government subsidies are derived, in the case of the two policies, RD investment subsidies and product subsidies for domestic firms, provided by the government. The results show that, the equilibrium output and the optimal social welfare under the RD investment subsidy policy are both less than those under the product subsidy policy; the optimal RD investment under the RD investment subsidy policy is less than that under the product subsidy policy; and the RD product subsidy has a more obvious incentive effect on firm RD investment. Under the background of the leading edge of technology of foreign firms, the product subsidy policy drawn up by the government to encourage RD innovation of domestic firms is more effective than the RD investment subsidy policy. 展开更多
关键词 research and development(R&D) investment investment subsidy product subsidy technology gap foreign firm competition
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FIRM序列在胎儿肠道病变诊断中的应用价值
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作者 王世琦 吉木阿拉 +1 位作者 刘寅 王齐艳 《中国科技期刊数据库 医药》 2022年第11期1-4,共4页
研究中选取胎儿肠道病变患儿,为精确病变的位置及病变诊断的准确性,提出FIRM序列,就FIRM序列在胎儿肠道病变诊断中的应用价值及主要的应用思路进行研究。方法 回顾性分析379例胎儿腹部MRI,包括快速反转恢复运动抑制(FIRM)、扰相位梯度回... 研究中选取胎儿肠道病变患儿,为精确病变的位置及病变诊断的准确性,提出FIRM序列,就FIRM序列在胎儿肠道病变诊断中的应用价值及主要的应用思路进行研究。方法 回顾性分析379例胎儿腹部MRI,包括快速反转恢复运动抑制(FIRM)、扰相位梯度回波(SPGR)、稳态梯度回波(FIESTA)序列,对各序列图像进行质量评价。结果 379例中169例胎儿腹部FIRM序列清晰显示肠道解剖结构,胎儿腹部病变正常显示,余210例未扫FIRM序列的病例受母体及胎儿运动干扰,图像信噪比低,伪影严重。结论 从研究结果中看出,FIRM序列是SPGR序列的补充,对于诊断胎儿腹部病变,提升诊断的准确性及效果等具有积极意义。 展开更多
关键词 firm序列 SPGR 胎儿 肠道病变 诊断 应用价值
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Leveraging core capabilities and environmental dynamism for food traceability and firm performance in a food supply chain: A moderated mediation model 被引量:13
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作者 SONG Mo-xi YANG Morgan Xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第8期1820-1837,共18页
This paper develops a moderated mediation model in which the interactive effects of food traceability and environmental dynamism on firm performance are mediated by the core capabilities(operating capabilities and mar... This paper develops a moderated mediation model in which the interactive effects of food traceability and environmental dynamism on firm performance are mediated by the core capabilities(operating capabilities and marketing capabilities)in food supply chain context, by invoking the indirect view of organizational learning theory. Our hypotheses were tested using hierarchical regression and bootstrapping methods with a sample of 216 food manufacturing firms in China, and a survey-based, two-informant design was used to collect data. The results revealed that operating and marketing capabilities fully mediate the food traceability-performance link. In addition, environmental dynamism positively moderates the food traceability-core capabilities link. Moreover, it is found that operating and marketing capabilities transform the interactive impacts of environmental dynamism and food traceability into firm performance. Our study offers a fine-grained picture of the essential food traceability-performance link by revealing for the first time that there is an interactive impacts of food traceability and environmental dynamism on firm performance via core capabilities. 展开更多
关键词 FOOD TRACEABILITY operating capabilities marketing capabilities ORGANIZATIONAL learning environmental DYNAMISM FOOD firm performance China
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Prediction of kiwifruit firmness using fruit mineral nutrient concentration by artificial neural network(ANN) and multiple linear regressions(MLR) 被引量:8
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作者 Ali Mohammadi Torkashvand Abbas Ahmadi Niloofar Layegh Nikravesh 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1634-1644,共11页
Many properties of fruit are influenced by plant nutrition. Fruit firmness is one of the most important fruit characteristics and determines post-harvest life of the fruit, in recent decades, artificial intelligence s... Many properties of fruit are influenced by plant nutrition. Fruit firmness is one of the most important fruit characteristics and determines post-harvest life of the fruit, in recent decades, artificial intelligence systems were employed for developing predictive models to estimate and predict many agriculture processes. In the present study, the predictive capabilities of multiple linear regressions (MLR) and artificial neural networks (ANNs) are evaluated to estimate fruit firmness in six months, including each of nutrients concentrations (nitrogen (N), potassium (K), calcium (Ca) and magnesium (Mg)) alone (P1), com- bination of nutrients concentrations (P2), nutrient concentration ratios alone (P3), and combination of nutrient concentrations and nutrient concentration ratios (P4). The results showed that MLR model estimated fruit firmness more accuracy than ANN model in three datasets (P1, P2 and P4). However, the application of P3 (N/Ca ratio) as the input dataset in ANN model improved the prediction of fruit firmness than the MLR model. Correlation coefficient and root mean squared error (RMSE) were 0.850 and 0.539 between the measured and the estimated data by the ANN model, respectively. Generally, the ANN model showed greater potential in determining the relationship between 6-mon-fruit firmness and nutrients concentration. 展开更多
关键词 artificial neural network firmNESS FRUIT KIWI multiple linear regression NUTRIENT
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Firmness evaluation of melon using its vibration characteristic and finite element analysis 被引量:12
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作者 NOURAIN Jamal 应义斌 +2 位作者 王剑平 饶秀勤 余朝刚 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第6期483-490,共8页
The “Huang gua” melons were measured for their physical properties including firmness and static elastic modulus. The vibrational characteristics of fruits and vegetables are governed by their elastic modulus (firmn... The “Huang gua” melons were measured for their physical properties including firmness and static elastic modulus. The vibrational characteristics of fruits and vegetables are governed by their elastic modulus (firmness), mass, and geometry. Therefore, it is possible to evaluate firmness of fruits and vegetables based on their vibrational characteristics. Analysis of the vibration responses of a fruit is suggested for measuring elastic properties (Firmness) non-destructively. The impulse response method is often used to measure firmness of fruits. The fruit was excited using three types of balls (wooden, steel and rubber) and the vibration is detected by an accelerometer. The Instron device was used to measure the static elastic modulus of the inner, middle and outer portions of melon flesh. Finite element (FE) technique was used to determine the optimum excitation location of the chosen measurement sensor and to analyze the mode shape fruits. Four types of mode shapes (torsional or flexural mode shape, first-type, second-type spherical mode and breathing mode shape) were found. Finite element simulation results agreed well with experimental results. Correlation between the firmness and resonant frequency (r2=0.91) and between the resonant frequency and stiffness factor (r2=0.74) existed. The optimum location and suitable direction for excitation and response measurement on the fruit were suggested. 展开更多
关键词 MELON SENSING Finite element Experimental modal analysis firmNESS
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How Chinese Financial Centers Integrate into Global Financial Center Networks:An Empirical Study Based on Overseas Expansion of Chinese Financial Service Firms 被引量:17
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作者 PAN Fenghua HE Ziyun +2 位作者 Thomas SIGLER Kirsten MARTINUS Ben DERUDDER 《Chinese Geographical Science》 SCIE CSCD 2018年第2期217-230,共14页
The increasing globalization of the Chinese economy has been enabled by both Chinese financial institutions operating globally as well as international firms operating within China. In geographical terms, this has bee... The increasing globalization of the Chinese economy has been enabled by both Chinese financial institutions operating globally as well as international firms operating within China. In geographical terms, this has been organized through a number of strategic cities serving as gateways for the exchange of financial functions, products and practices between China and the global economy. Drawing on location data of financial service firms in China listed on stock exchanges in Shenzhen, Shanghai and Hong Kong, this paper shows that Chinese financial firms are expanding globally and how Chinese financial centers are positioned and connected in the urban networks shaped by these financial service firms. It is found that Hong Kong, China, holds strategic positions in the integration of Chinese cities into global financial center networks, and that establishing a foothold in global financial centers such as New York and London has been a priority for Chinese financial institutions. The increasing capital flows directed by Chinese financial institutionssuggests a shifting global financial geography, with numerous Chinese cities playing increasingly important roles within global financial center networks. 展开更多
关键词 urban networks corporate networks financial service firms global financial centers China
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Identification of Behavior of Voluntary Traceability and Analysis of Its Determinants: A Case Study of Hog Slaughtering and Processing Firms in Zhejiang Province,China 被引量:2
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作者 ZHOU Jie-hong YAN Zhen LIU Qing-yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第6期1112-1121,共10页
In recent years, the Chinese government has highlighted the importance of adopting hog safety/quality traceability, and a growing amount of research continues to entice firms to adopt traceability systems. In this stu... In recent years, the Chinese government has highlighted the importance of adopting hog safety/quality traceability, and a growing amount of research continues to entice firms to adopt traceability systems. In this study, a survey was conducted on a sample of pig slaughtering and processing firms in Zhejiang, China through personal interviews and emails. The aim of this study was to examine the determinants of firm behavior on the implementation of voluntary traceability systems with more stringent standards and controls than those of the mandatory system in China. The results revealed that motivation based on product quality improvement, capital ability and role perception (business type) had significantly positive relationships with a firm's voluntary traceability. Other incentives, such as operation improvement, recall risk reduction, reduced occurrence of safety issues, and technical strength were not found to be supportive in our study. This study provides an opportunity to better understand the determinants of firm behavior on voluntary traceability, particularly in light of the fact that some Chinese firms are facing the threat of criminal action for the use of illegal additives and the abuse of Clenbuterol. Policy recommendations on encouraging the implementation of pork safety voluntary traceability by hog slaughtering and processing firms are also discussed. 展开更多
关键词 voluntary traceable behavior product quality improvement capital ability role perception hog slaughtering and processing firm
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Application of NIR spectroscopy for firmness evaluation of peaches 被引量:9
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作者 Xia-ping FU Yi-bin YING Ying ZHOU Li-juan XIE Hui-rong XU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第7期552-557,共6页
The use of near infrared (NIR) spectroscopy was proved to be a useful tool for quality analysis of fruits. A bifurcated fiber type NIR spectrometer, with a detection range of 800-2500 nm by InGaAs detector, was used... The use of near infrared (NIR) spectroscopy was proved to be a useful tool for quality analysis of fruits. A bifurcated fiber type NIR spectrometer, with a detection range of 800-2500 nm by InGaAs detector, was used to evaluate the firmness of peaches. Anisotropy of NIR spectra and firmness of peaches in relation to detecting positions of different parts (including three latitudes and three longitudes) were investigated. Both spectra absorbency and firmness of peach were influenced by longitudes (i, ii, iii) and latitudes (A, B, C). For modeling, two thirds of the samples were used as the calibration set and the remaining one third were used as the validation or prediction set. Partial least square regression (PLSR) models for different longitude and latitude spectra and for the whole fruit show that collecting several NIR spectra from different longitudes and latitudes of a fruit for NIR calibration modeling can improve the modeling performance. In addition, proper spectra pretreatments like scattering correction or derivative also can enhance the modeling performance. The best results obtained in this study were from the holistic model with multiplicative scattering correction (MSC) pretreatment, with correlation coefficient of cross-validation γcv=0.864, root mean square error of cross-validation RMSECV=6.71 N, correlation coefficient of calibration r=0.948, root mean square error of calibration RMSEC=4.21 N and root mean square error of prediction RMSEP=5.42 N. The results of this study are useful for further research and application that when applying NIR spectroscopy for objectives with anisotropic differences, spectra and quality indices are necessarily measured from several parts of each object to improve the modeling performance. 展开更多
关键词 Near infrared (NIR) ANISOTROPY PEACH firmNESS Partial least square regression (PLSR)
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Firm embedding behavior of annular grooved projectiles impacting ductile metal targets 被引量:1
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作者 Qi Huang Shun-shan Feng +3 位作者 Xu-ke Lan Chao-nan Chen Yong-xiang Dong Tong Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期768-778,共11页
Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal plates.They could become embedded solidly in the target surface dur... Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal plates.They could become embedded solidly in the target surface during low-velocity impact.In this investigation,the firm embedding behavior of AGP was observed by impact experiments.Corresponding numerical simulations provided a better understanding of this process.Experimental and numerical results indicated that the firm embedding behavior of AGP was mainly due to the filling-material in the groove rather than the friction between the projectile and target,unlike traditional shape such as conical projectile.According to observation,firm embedding process can generally be subdivided into four stages:initial-cratering stage,groove-filling stage,fillingmaterial failure stage and rebound vibration stage.Moreover,the damage mechanics of target material around crater was obtained through microscopic tests.A comparison of the cross-sectional figures between the experiment and simulation proved that the analysis and the proposed method were reasonable and feasible,which further demonstrated that the firm embedding behavior has application potential in new concept warheads. 展开更多
关键词 ANNULAR grooved projectile (AGP) Impact firm EMBEDDING BEHAVIOR Flow characteristics Microscopic tests
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加权firm阈值奇异值分解及其旋转机械故障诊断 被引量:2
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作者 常妍 蔡改改 胡耀阳 《噪声与振动控制》 CSCD 北大核心 2023年第5期135-141,187,共8页
奇异值分解(Singular value decomposition,SVD)作为一种有效的信号降噪方法广泛应用于旋转机械振动信号周期性瞬态冲击提取中。传统SVD以能量为导向,无法提取出能量较弱但含故障信息丰富的奇异分量(Singular Component,SC)。为此,提出... 奇异值分解(Singular value decomposition,SVD)作为一种有效的信号降噪方法广泛应用于旋转机械振动信号周期性瞬态冲击提取中。传统SVD以能量为导向,无法提取出能量较弱但含故障信息丰富的奇异分量(Singular Component,SC)。为此,提出加权firm阈值奇异值分解(Weighted Firm Singular Value Decomposition,WFSVD)方法。该方法首先引入平方包络谱峭度(Squared Envelope Spectrum Kurtosis,SESK)作为量化故障敏感度的指标,以评估各个SC所含故障信息的丰富程度;其次,将SESK作为权重因子引入到基于firm阈值的SC去噪中,设计基于SESK的加权firm阈值SC去噪策略;最后,重构信号,实现信号降噪并有效提取故障特征。对于仿真信号与试验数据的分析验证了所提方法在周期性微弱瞬态冲击提取及旋转机械故障诊断中的有效性。 展开更多
关键词 故障诊断 奇异值分解 平方包络谱峭度 瞬态冲击提取 加权firm阈值
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基于(m,k)-firm约束规范的混合任务调度算法研究 被引量:1
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作者 廖义林 吕英 沈崧 《计算机工程与设计》 CSCD 北大核心 2008年第19期4894-4897,4902,共5页
讨论了在准实时环境下,包括准实时周期任务和准实时非周期任务在内的混合任务调度算法HTSF。HTSF算法是在满足周期任务(m,k)-firm约束规范的前提下提高非周期任务可调度性,同时合理利用可用空闲时间,提高整个系统的服务质量。HTSF算法... 讨论了在准实时环境下,包括准实时周期任务和准实时非周期任务在内的混合任务调度算法HTSF。HTSF算法是在满足周期任务(m,k)-firm约束规范的前提下提高非周期任务可调度性,同时合理利用可用空闲时间,提高整个系统的服务质量。HTSF算法给出了非周期任务的可调度性分析方法,同时采用静态调度与动态调度相结合的方法调度周期任务和非周期任务。模拟测试结果显示,系统对非周期任务的接收率比同类相关算法的接收率高。 展开更多
关键词 准实时任务 混合任务调度 周期任务 非周期任务 服务质量 截止期限单调调度策略
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Does board gender diversity affect firm performance?Empirical evidence from Standard & Poor’s 500 Information Technology Sector 被引量:2
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作者 Liliana Nicoleta Simionescu Ştefan Cristian Gherghina +1 位作者 Hiba Tawil Ziad Sheikha 《Financial Innovation》 2021年第1期1124-1168,共45页
The essence of this study is to investigate the influence of the board gender diversity on firms’accounting and market-based performance using a sample of Standard&Poor’s 500 companies belonging to the informati... The essence of this study is to investigate the influence of the board gender diversity on firms’accounting and market-based performance using a sample of Standard&Poor’s 500 companies belonging to the information technology sector over 12 years.Using the pooled ordinary least squares(OLS)method,the outcomes provide evidence for a positive influence of women on corporate boards on both measures of company performance,except for the percentage of female executives in the case of return on assets(ROA).After estimating the fixed effects and random-effects through panel data,the econometric outcomes show no statistically significant association among board gender diversity and ROA but a positive influence of the number and percentage of women on board on price-to-earnings ratio. 展开更多
关键词 Gender diversity firm performance Pooled OLS Fixed-effects Randomeffects
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Game theory model of exit selection in pedestrian evacuation considering visual range and choice firmness 被引量:1
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作者 Wei-Li Wang Fang-Fang Wan Siu-Ming Lo 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期355-362,共8页
Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much infor... Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much information a pedestrian can perceive,thus the number of pedestrians within the visual field can be used to estimate waiting time at the exit.Besides,the choice firmness that reflects the degree to which a pedestrian would persist in his/her previous choice of exit is proposed.By integrating game theory into a cellular automata simulation framework,the pedestrian exit choice mechanism is investigated and explicitly modeled in this paper.A systematic analysis of the key factors influencing pedestrian evacuation is conducted,including visual radius and choice firmness of a pedestrian,initial crowd distribution of the room,exit layout as well as exit width.It is found that low choice firmness level can lead to unnatural pedestrian behavior such as wandering,which is adverse to evacuation.The longer the pedestrian's visual radius,the earlier the pedestrian can determine his/her final selection of the exit.Compared with the scenario where the pedestrians are randomly distributed,pedestrians clustered together in a corner of the room lead to high crowd density and imbalanced use of exits.Furthermore,the exit layout and exit width also have a certain influence on pedestrian evacuation process.The results of this paper may be of benefit to the formulation of behavioral rules in other pedestrian simulation models. 展开更多
关键词 game theory exit selection visual range choice firmness
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