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A Selective‑Response Hypersensitive Bio‑Inspired Strain Sensor Enabled by Hysteresis Effect and Parallel Through‑Slits Structures
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作者 Qun Wang Zhongwen Yao +8 位作者 Changchao Zhang Honglie Song Hanliang Ding Bo Li Shichao Niu Xinguan Huang Chuanhai Chen Zhiwu Han Luquan Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期139-153,共15页
Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into... Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into one flexible strain sensor remains a huge challenge.Herein,inspired by the hysteresis strategy of the scorpion slit receptor,a bio-inspired flexible strain sensor(BFSS)with parallel through-slit arrays is designed and fabricated.Specifically,BFSS consists of conductive monolayer graphene and viscoelastic styrene–isoprene–styrene block copolymer.Under the synergistic effect of the bio-inspired slit structures and flexible viscoelastic materials,BFSS can achieve both hypersensitivity and highly selective frequency response.Remarkably,the BFSS exhibits a high gage factor of 657.36,and a precise identification of vibration frequencies at a resolution of 0.2 Hz through undergoing different morphological changes to high-frequency vibration and low-frequency vibration.Moreover,the BFSS possesses a wide frequency detection range(103 Hz)and stable durability(1000 cycles).It can sense and recognize vibration signals with different characteristics,including the frequency,amplitude,and waveform.This work,which turns the hysteresis effect into a"treasure,"can provide new design ideas for sensors for potential applications including human–computer interaction and health monitoring of mechanical equipment. 展开更多
关键词 Bio-inspired strain sensors Hysteresis effect HYPERSENSITIVITY selective frequency response Health monitoring applications
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ZResponse to selection,heritability and genetic correlations between body weight and body size in Pacific white shrimp,Litopenaeus vannamei 被引量:6
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作者 安迪 刘小林 +1 位作者 黄皓 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第2期200-205,共6页
To quantify the response to selection, heritability and genetic correlations between weight and size ofLitopenaeus vannamei, the body weight (BW), total length (TL), body length (BL), first abdominal segment dep... To quantify the response to selection, heritability and genetic correlations between weight and size ofLitopenaeus vannamei, the body weight (BW), total length (TL), body length (BL), first abdominal segment depth (FASD), third abdominal segment depth (TASD), first abdominal segment width (FASW), and partial carapace length (PCL) of 5-month-old parents and of offspring were measured by calculating seven body measurings of offspring produced by a nested mating design. Seventeen half-sib families and 42 full-sib families ofL. vannamei were produced using artificial fertilization from 2-4 dams by each sire, and measured at around five months post-metamorphosis. The results show that heritabilities among various traits were high: 0.515±0.030 for body weight and 0.394±0.030 for total length. After one generation of selection, the selection response was 10.70% for offspring growth. In the 5th month, the realized heritability for weight was 0.296 for the offspring generation. Genetic correlations between body weight and body size were highly variable. The results indicate that external morphological parameters can be applied during breeder selection for enhancing the growth without sacrificing animals for determining the body size and breed ability; and selective breeding can be improved significantly, simultaneously with increased production. 展开更多
关键词 genetic correlation GROWTH HERITABILITY Litopenaeus vannamei selection response
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Path Selection in Disaster Response Management Based on Q-learning 被引量:3
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作者 Zhao-Pin Su Jian-Guo Jiang +1 位作者 Chang-Yong Liang2' 3 Guo-Fu Zhang Guo-Fu Zhang 《International Journal of Automation and computing》 EI 2011年第1期100-106,共7页
Suitable rescue path selection is very important to rescue lives and reduce the loss of disasters, and has been a key issue in the field of disaster response management. In this paper, we present a path selection algo... Suitable rescue path selection is very important to rescue lives and reduce the loss of disasters, and has been a key issue in the field of disaster response management. In this paper, we present a path selection algorithm based on Q-learning for disaster response applications. We assume that a rescue team is an agent, which is operating in a dynamic and dangerous environment and needs to find a safe and short path in the least time. We first propose a path selection model for disaster response management, and deduce that path selection based on our model is a Markov decision process. Then, we introduce Q-learning and design strategies for action selection and to avoid cyclic path. Finally, experimental results show that our algorithm can find a safe and short path in the dynamic and dangerous environment, which can provide a specific and significant reference for practical management in disaster response applications. 展开更多
关键词 Disaster response management path selection AGENT SELF-ORGANIZING Markov decision process Q-learning.
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Genetic Parameters of Body Length and Response to Selection for Growth Across Four Generations of Artemia sinica
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作者 KONG Zhangwei KONG Jie +3 位作者 LUAN Sheng ZHANG Zhiwei YU Chifang LUO Kun 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期203-209,共7页
To investigate the genetic components of growth in the brine shrimp Artemia sinica, we estimated the genetic parameters of body length and the response to selection using a fully pedigreed population of A. sinica. The... To investigate the genetic components of growth in the brine shrimp Artemia sinica, we estimated the genetic parameters of body length and the response to selection using a fully pedigreed population of A. sinica. The base population was generated from four wild founder populations. We tested 4160 offspring in 360 families over four generations for growth and survival performance. Across four generations, we produced full-and half-sib families with nested mating, where two dams were mated to the same sire. Individual body length was measured for each nauplius at day 20 post-hatching. Heritability of body length was estimated across four generations with the restricted maximum likelihood method. The heritability of body length in A. sinica was low(0.14 ± 0.05), and the common environmental effect was 0.14 ± 0.02. We estimated the response to selection for body length by calculating the difference in the mean breeding values between different generations. The accumulated genetic gain in body length was 278.94 μm after three generations of selection. This low response to selection was probably caused by the low heritability of body length, small sample size, and the low selection intensity(50%). The results suggest that A. sinica selective breeding programs must be changed to generate any substantial, sustainable genetic increases in body length. We suggest that optimal genetic gains could be achieved by introducing wild strains into the nuclear breeding population to increase genetic variation, and by increasing the size of the breeding population to allow for increased selection intensity. 展开更多
关键词 ARTEMIA SINICA body length HERITABILITY selection responseS
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Responses to two-way selection on growth in mass-spawned F_1 progeny of Argopecten irradians concentricus(Say)
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作者 王辉 刘进 +2 位作者 李艳红 朱晓闻 刘志刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期349-357,共9页
In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop (Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program c... In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop (Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population ofA. i. concentricus, and divided into two groups in shell length (anterior-posterior measurement): large (4.91-6.02 cm, n=74) and small (3.31-4.18 cm, n=72). At the same time, a control group was also randomly sampled (4.21-4.88 cm, n=80). Mass-spawned F1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way (or upward-downward) selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences (P〈0.01) were found in hatching rate, survival rate and daily growth of F~ progenies, but not in fertilization rate (P〉0.05), among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group (P〈0.05), which in turn were larger than those of small-sized group (P〈0.05). Responses to selection by shell length and body weight were 0.32±0.04 cm and 2.18±0.05 g, respectively, for the upward selection, and -0.14±0.03 cm and -2.77±0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38±0.06 cm and 0.22±0.07 g for the upward selection, and 0.24±0.06 cm and 0.37±0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China. 展开更多
关键词 Argopecten irradians concentricus (Say) two-way selection response to selection realized heritability F1 progeny mass-spawned
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A Practical Solution to the Small Sample Size Bias and Uncertainty Problems of Model Selection Criteria in Two-Input Process Multiple Response Surface Methodology Datasets
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作者 Domingo Pavolo Delson Chikobvu 《Open Journal of Statistics》 2019年第1期109-142,共34页
Multiple response surface methodology (MRSM) most often involves the analysis of small sample size datasets which have associated inherent statistical modeling problems. Firstly, classical model selection criteria in ... Multiple response surface methodology (MRSM) most often involves the analysis of small sample size datasets which have associated inherent statistical modeling problems. Firstly, classical model selection criteria in use are very inefficient with small sample size datasets. Secondly, classical model selection criteria have an acknowledged selection uncertainty problem. Finally, there is a credibility problem associated with modeling small sample sizes of the order of most MRSM datasets. This work focuses on determination of a solution to these identified problems. The small sample model selection uncertainty problem is analysed using sixteen model selection criteria and a typical two-input MRSM dataset. Selection of candidate models, for the responses in consideration, is done based on response surface conformity to expectation to deliberately avoid selection of models using the problematic classical model selection criteria. A set of permutations of combinations of response models with conforming response surfaces is determined. Each combination is optimised and results are obtained using overlaying of data matrices. The permutation of results is then averaged to obtain credible results. Thus, a transparent multiple model approach is used to obtain the solution which gives some credibility to the small sample size results of the typical MRSM dataset. The conclusion is that, for a two-input process MRSM problem, conformity of response surfaces can be effectively used to select candidate models and thus the use of the problematic model selection criteria is avoidable. 展开更多
关键词 MULTIPLE response Surface Methodology All POSSIBLE Regressions Model selection CRITERIA Data MATRICES
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Study on the Relation between Selecting and Programming Responses in PRP Paradigm
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《Journal of Modern Transportation》 1997年第2期71-78,共8页
Experiments show that programming response is one of the multimission completed simultaneously in the stage of selecting response. Therefore, a programming response does not constitute a bottleneck. The results indica... Experiments show that programming response is one of the multimission completed simultaneously in the stage of selecting response. Therefore, a programming response does not constitute a bottleneck. The results indicate that if improved performance of an overt response Ri in the set of alternative response R(i.e.RRi|i=1,2,…,n) is expected, it is necessary to simplify the average response complexity of the set. If only the complexity of operation Ri is simplified, little effect will be produced in improving performance. The response selection bottleneck is confirmed by the results of PRP (psychological refractory period) experiments. Based on the results and the selection response bottleneck model, a key assumption about working process of response selection-scanning response selection model is proposed. 展开更多
关键词 PRP paradigm selecting response programming response bottleneck.
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Self-suspended Pure Polydiacetylene Nanoparticles with Selective Response to Lysine and Arginine
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作者 Jun Luo Kai-yu Fu +1 位作者 Hai-yan Dong Dao-yong Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第6期749-753,I0002,共6页
We demonstrate a very convenient access to self-suspended pure poly(10,12-pentacosadiynoic acid) (PDA) nanoparticles (NPs) simply by adding the ethanol solution of diacetylene monomer to water, followed by UV ir... We demonstrate a very convenient access to self-suspended pure poly(10,12-pentacosadiynoic acid) (PDA) nanoparticles (NPs) simply by adding the ethanol solution of diacetylene monomer to water, followed by UV irradiation. The as-obtained PDA NPs are of high purity because no any initiator, catalyst or stabilizer was used during the whole process. The stabilizer-free PDA NPs are stable in the aqueous suspension. Due to the high purity and stability, the PDA NPs can respond sensitively and selectively to lysine and arginine among 18 kinds of water soluble natural amino acids; without the competitive interaction from the stabilizer, the sensitivity was enhanced. 展开更多
关键词 POLYDIACETYLENE selective response LYSINE ARGININE
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Elucidation of Abnormal Potential Responses of Cation-Selective Electrodes with Solid-State Membranes to Aqueous Solutions of CuCl2 and CdI2
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作者 Yoshihiro Kudo Daisuke Todoroki +3 位作者 Nobukazu Suzuki Naoki Horiuchi Shoichi Katsuta Yasuyuki Takeda 《American Journal of Analytical Chemistry》 2011年第1期9-17,共9页
An empirical solution to abnormal potential responses, showing peaks of emf, of commercial Cu2+- and Cd2+-selective electrodes with solid-state membranes was proposed for aqueous solutions of CuCl2 and CdI2. The two-s... An empirical solution to abnormal potential responses, showing peaks of emf, of commercial Cu2+- and Cd2+-selective electrodes with solid-state membranes was proposed for aqueous solutions of CuCl2 and CdI2. The two-step processes of Mn+ + Yn? (s: solid phase) MY(s) and MY(s) + 2X? X2MY2?(s) (n = 1, 2) at a test solution/electrode-interface were considered as a model. Here, Mn+, Yn?, and X? refer to a divalent or univalent cation, functional groups of electrode materials, and a halide ion (X? = Cl?, Br?, I?), respectively. By applying electrochemical potentials to these processes at n = 2, we derived an equation. Regression analyses based on the equation reproduced well the plots of emf versus log 2(*[M]t) for the Cd(II) and Cu(II) systems: *[M]t denotes a total concentration of species relevant to M2+ in a bulk of the aqueous solution. Also, we obtained log Ks(CdBr2) = 4.28 ? 0.22, log Ks(CdI2) = 6.98 ? 0.05, log Ks(CuCl2) = 3.96 ? 0.09, and log Ks(CuBr2) = 11.4 at 25?C. The magnitude in ?log Ks reflected that in the logarithmic solubility product, log {*[M2+](*[X?])2}, for bulk water, where *[M2+] or *[X?] denotes a molar concentration of the bulk solu-tion of M2+ or X? at equilibrium, respectively. Moreover, a mixture of CuSO4 with NaCl at the molar ratio of 1:1 yielded a plot similar to that of CuCl2. 展开更多
关键词 Cation-selective Electrode SOLID-STATE Membranes Potential response Solubility Product POTENTIOMETRY
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Radiological response and inflammation scores predict tumour recurrence in patients treated with transarterial chemoembolization before liver transplantation 被引量:5
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作者 Daniele Nicolini Andrea Agostini +7 位作者 Roberto Montalti Federico Mocchegiani Cinzia Mincarelli Alessandra Mandolesi Nicola L Robertson Roberto Candelari Andrea Giovagnoni Marco Vivarelli 《World Journal of Gastroenterology》 SCIE CAS 2017年第20期3690-3701,共12页
To investigate the prognostic value of the radiological response after transarterial chemoembolization (TACE) and inflammatory markers in patients affected by hepatocellular carcinoma (HCC) awaiting liver transplantat... To investigate the prognostic value of the radiological response after transarterial chemoembolization (TACE) and inflammatory markers in patients affected by hepatocellular carcinoma (HCC) awaiting liver transplantation (LT).METHODSWe retrospectively evaluated the preoperative predictors of HCC recurrence in 70 patients treated with conventional (n = 16) or doxorubicin-eluting bead TACE (n = 54) before LT. The patient and tumour characteristics, including the static and dynamic alpha-fetoprotein, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio (PLR) measurements, were recorded. Treatment response was classified according to the modified Response Evaluation Criteria in Solid Tumours (mRECIST) and the European Association for the Study of the Liver (EASL) criteria as complete response (CR), partial response (PR), stable disease or progressive disease. After examination of the explanted livers, histological necrosis was classified as complete (100% of the cumulative tumour area), partial (50%-99%) or minimal (< 50%) and was correlated with the preoperative radiological findings.RESULTSAccording to the pre-TACE radiological evaluation, 22/70 (31.4%) and 12/70 (17.1%) patients were beyond Milan and University of San Francisco (UCSF) criteria, respectively. After TACE procedures, the objective response (CR + PR) rates were 71.4% and 70.0% according to mRECIST and EASL criteria, respectively. The agreement between the two guidelines in defining the radiological response was rated as very good both for the overall and target lesion response (weighted k-value: 0.98 and 0.93, respectively). Complete and partial histological necrosis were achieved in 14/70 (20.0%) and 28/70 (40.0%) patients, respectively. Using histopathology as the reference standard, mRECIST criteria correctly classified necrosis in 72.9% (51/70) of patients and EASL criteria in 68.6% (48/70) of cases. The mRECIST non-response to TACE [Exp(b) = 9.2, p = 0.012], exceeding UCSF criteria before TACE [Exp(b) = 4.7, p = 0.033] and a preoperative PLR > 150 [Exp(b) = 5.9, p = 0.046] were independent predictors of tumour recurrence.CONCLUSIONThe radiological response and inflammatory markers are predictive of tumour recurrence and allow the proper selection of TACE-treated candidates for LT. 展开更多
关键词 Liver transplantation Recurrence-free survival Hepatocellular carcinoma Radiological response Locoregional therapies Inflammatory markers selection criteria
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A new look at the response surface method for reliability analysis using chaos theory 被引量:1
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作者 Ding Youliang, Li Aiqun and Deng Yang College of Civil Engineering, Southeast University, Nanjing 210096, China Lecturer Professor PhD Student 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第3期329-335,共7页
To overcome excessive computation errors and convergence failures encountered in an iterative calculation of the reliability index using the response surface method (RSM) for some nonlinear limit state functions, th... To overcome excessive computation errors and convergence failures encountered in an iterative calculation of the reliability index using the response surface method (RSM) for some nonlinear limit state functions, this study investigates an essential factor based on chaotic dynamics theory. The bifurcation diagrams of the reliability index are presented for some typical nonlinear limit state functions, and the computation results from the mapping functions due to the RSM iterations show the complicated dynamic phenomena such as the periodic oscillation, as well as bifurcation and chaos. From the numerical examples, it is concluded that the parameter of selection range fplays an important role in the convergence of the RSM iteration, and an improved RSM iterative algorithm is proposed with regard to the incorporation of the iterative sequential function of selection rangef The proposed method is shown to be efficient and to yield accurate results. 展开更多
关键词 structural reliability response surface method chaotic dynamics convergence failure selection range NONLINEARITY
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Effect of Genetic Connectedness on the Selection Results of Breeding Pigs 被引量:1
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作者 ZHANG Hao LI Jia-qi WANG Chong LIU Xiao-hong CHEN Yao-sheng 《Agricultural Sciences in China》 CAS CSCD 2005年第11期872-876,共5页
Two pig populations were simulated with Monte Carlo method; each consisted of 5 boars and 50 sows per generation. Genetic connectedness between herds was established by randomly selecting 1 or 2 boars from one populat... Two pig populations were simulated with Monte Carlo method; each consisted of 5 boars and 50 sows per generation. Genetic connectedness between herds was established by randomly selecting 1 or 2 boars from one population to mate sows of the other population. Breeding pigs were selected within populations according to animal model BLUP. The benefits of genetic connectedness between herds were examined. The results showed that, the average coefficients of inbreeding decreased, while the cumulative selection responses of populations increased, and the higher response occurred randomly in the two populations at generation 5 with the increase of the genetic connectedness between herds. Selection response was affected by genetic connectedness and trait heritability, the lower heritability and higher connectedness, the better selection results. When the number of exchanged litters between populations per generation was 6 litters, the selection results reached a reflection point; if the number of exchanged litters between populations increased further from this point, neither the increase of the cumulative selection responses nor the decrease of coefficients of inbreeding was significant. 展开更多
关键词 PIGS Genetic connectedness Cumulative selection response Coefficient of inbreeding
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Modeling personalized head-related impulse response using support vector regression 被引量:1
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作者 黄青华 方勇 《Journal of Shanghai University(English Edition)》 CAS 2009年第6期428-432,共5页
A new customization approach based on support vector regression (SVR) is proposed to obtain individual headrelated impulse response (HRIR) without complex measurement and special equipment. Principal component ana... A new customization approach based on support vector regression (SVR) is proposed to obtain individual headrelated impulse response (HRIR) without complex measurement and special equipment. Principal component analysis (PCA) is first applied to obtain a few principal components and corresponding weight vectors correlated with individual anthropometric parameters. Then the weight vectors act as output of the nonlinear regression model. Some measured anthropometric parameters are selected as input of the model according to the correlation coefficients between the parameters and the weight vectors. After the regression model is learned from the training data, the individual HRIR can be predicted based on the measured anthropometric parameters. Compared with a back-propagation neural network (BPNN) for nonlinear regression, better generalization and prediction performance for small training samples can be obtained using the proposed PCA-SVR algorithm. 展开更多
关键词 head-related impulse response (HRIR) personalization principal component analysis (PCA) support vector regression (SVR) variable selection
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Light-responsive adsorbentswithtunableadsorbent-adsorbate interactions forselective CO_(2) capture
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作者 Peng Tan Yao Jiang +5 位作者 Qiurong Wu Chen Gu Shichao Qi Qiang Zhang Xiaoqin Liu Linbing Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期104-111,共8页
Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong i... Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong interactions to reach a high efficiency in the adsorption processes.Herein,we fabricated lightresponsive adsorbents with tunable adsorbent–adsorbate interactions for CO_(2) capture.The adsorbents were synthesized by introducing primary and secondary amines into a mesoporous silica that had been grafted with azobenzene groups on the surfaces.The target-specific amine sites render the adsorbents significantly selective in the uptake of CO_(2) over CH_(4),and the azobenzene groups were used as lightresponsive switches to influence the adsorbent–adsorbate interactions.The adsorbents can freely adsorb CO_(2) when the azobenzene groups are in the trans state.Ultraviolet-light irradiation makes the azobenzene groups transform to the cis configuration,which greatly hinders amines in the uptake of CO_(2).The caused difference of adsorption capacity can reach 34.9%.The alternative irradiation by ultravioletand visible-light can lead to a recyclable regulation on adsorption performance.The changes of the electrostatic potentials of amines are responsible for the light-induced regulation on adsorption. 展开更多
关键词 Adsorbents CO_(2)capture selectivity Light responsiveness AZOBENZENE
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Year-round multi-scale habitat selection by Crested Tit(Lophophanes cristatus)in lowland mixed forests(northern Italy)
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作者 Alessandro Berlusconi Alessio Martinoli +8 位作者 Lucas AWauters Giulia Tesoro Stefania Martini Erminio Clerici Gualtiero Guenzani Gabriele Pozzi Diego Rubolini Michelangelo Morganti Adriano Martinoli 《Avian Research》 SCIE CSCD 2022年第4期461-467,共7页
Determining how animals respond to resource availability across spatial and temporal extents is crucial to understand ecological processes underpinning habitat selection.Here,we used a multi-scale approach to study th... Determining how animals respond to resource availability across spatial and temporal extents is crucial to understand ecological processes underpinning habitat selection.Here,we used a multi-scale approach to study the year-round habitat selection of the Crested Tit(Lophophanes cristatus)in a semi-natural lowland woodland of northern Italy,analysing different habitat features at each scale.We performed Crested Tit censuses at three different spatial scales.At the macrohabitat scale,we used geolocalized observations of individuals to compute Manly's habitat selection index,based on a detailed land-use map of the study area.At the microhabitat scale,the trees features were compared between presence and absence locations.At the foraging habitat scale,individual foraging birds and their specific position on trees were recorded using focal animal sampling.Censuses were performed during both the breeding(March to May)and wintering(December to January)seasons.At the macrohabitat scale,the Crested Tits significantly selected pure and mixed pine forests and avoided woods of alien plant species,farmlands and urban areas.At the microhabitat scale,old pine woods with dense cover were selected,with no significant difference in the features of tree selection between the two phenological phases.At the foraging habitat scale,the species was observed spending more time foraging in the canopies than in the understorey,using mostly the portion of Scots Pine(Pinus sylvestris)canopies closer to the trunk in winter,while during the breeding period,the whole canopy was visited.Overall,breeding and wintering habitats largely overlapped in the Crested Tit.Based on our findings,lowland Crested Tits can be well defined as true habitat specialists:they are strictly related to some specific coniferous woodland features.Noteworthily,compared to other tit species,which normally show generalist habits during winter,the Crested Tit behaves as a habitat specialist also out of the breeding season.Our study stressed the importance of considering multi-scale(both spatial and phenological)habitat selection in birds. 展开更多
关键词 Crested tit Functional response Habitat selection Multi-scale approach Scots pine
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Role of CuO-ZnO Heterojunctions in Gas Sensing Response of CuO-ZnO Thick Films
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作者 Madhavrao K. Deore Vishwas B. Gaikwad Gotan H. Jain 《Journal of Physical Science and Application》 2016年第2期51-60,共10页
The CuO-doped ZnO thick films were prepared by the screen printing technique. The CuO doped ZnO composite materials were obtained by mixing AR grade (99.9% pure) Zinc Oxide powder mechanochemically in acetone medium... The CuO-doped ZnO thick films were prepared by the screen printing technique. The CuO doped ZnO composite materials were obtained by mixing AR grade (99.9% pure) Zinc Oxide powder mechanochemically in acetone medium with various weight percentages of Copper Chloride (CulCI2.2H20) powder (1, 3, 5, 7 and 9wt.%). The prepared materials were sintered at 1,000 ℃ for 12 h in air ambience and ball milled to ensure sufficiently fine particle size. The films were characterized by different techniques with respect to their surface morphology and compositional property by means of SEM (scanning electron microscope) and EDXA (energy dispersive x-ray analysis). The surface morphology of the films was studied by SEM and it shows the films are porous in nature and petal-shaped grains of sizes varies from 220 nm to 250 nm were observed. The final composition of each film was determined by the EDXA analysis. The gas response of undoped ZnO and CuO doped ZnO films was studied for different gases such as CO, C12, NH3, Ethanol, H2S and LPG at operating temperature ranging from 50 ℃ to 400 ℃. The 7wt.% CuO-doped ZnO film shows good response to H2S gas (100 ppm) at 250 ℃. 展开更多
关键词 CuO-ZnO heterojunctions H2S thick film gas response selectIVITY response and recovery time.
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Choosing a Method to Reduce Selection Bias: A Tool for Researchers
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作者 Claire Keeble Graham Richard Law +1 位作者 Stuart Barber Paul D. Baxter 《Open Journal of Epidemiology》 2015年第3期155-162,共8页
Selection bias is well known to affect surveys and epidemiological studies. There have been numerous methods proposed to reduce its effects, so many that researchers may be unclear which method is most suitable for th... Selection bias is well known to affect surveys and epidemiological studies. There have been numerous methods proposed to reduce its effects, so many that researchers may be unclear which method is most suitable for their study;the wide choice may even deter some researchers, for fear of choosing a sub-optimal approach. We propose a straightforward tool to inform researchers of the most promising methods available to reduce selection bias and to assist the search for an appropriate method given their study design and details. We demonstrate the tool using three examples where selection bias may occur;the tool quickly eliminates inappropriate methods and guides the researcher towards those to consider implementing. If more studies consider selection bias and adopt methods to reduce it, valuable time and resources will be saved, and should lead to more focused research towards disease prevention or cure. 展开更多
关键词 selection BIAS PARTICIPATION BIAS NON-response METHODOLOGY
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中国式刑事证明结构:分段包干与选择性接力 被引量:1
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作者 李昌盛 《浙江工商大学学报》 北大核心 2024年第1期60-71,共12页
1979年颁行的《刑事诉讼法》确立了我国分段包干与选择性接力的证明结构。它既体现在侦诉审关系中,也体现在上下审关系中。在这一结构中,公检法在各自主导的诉讼阶段只有调查程序和方式的差异,并无查证责任和目标的差异。后端办案机关... 1979年颁行的《刑事诉讼法》确立了我国分段包干与选择性接力的证明结构。它既体现在侦诉审关系中,也体现在上下审关系中。在这一结构中,公检法在各自主导的诉讼阶段只有调查程序和方式的差异,并无查证责任和目标的差异。后端办案机关有接力查证的责任。接力者具有依照法定证明标准选择是否接力的判断权,也有选择接力主体、范围和方法的裁量权。《刑事诉讼法》虽然历经多次修改,但均朝着优化结构的方向前行。我国刑事证明结构具有如下鲜明特色:一是事实认定权力的去中心主义,二是专门机关查证责任的同质化,三是查证范围认定权的单元化,四是“调查”真相演变为“接着查”真相,五是作为查明真相协助者的辩方。 展开更多
关键词 刑事证明结构 分段包干 选择性接力 查证责任
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煤层H_(2)S与煤脱硫协同治理研究
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作者 高飞 张芸鸣 +2 位作者 杨玉龙 侯渊 申佳琦 《安全与环境学报》 CAS CSCD 北大核心 2024年第8期3116-3125,共10页
为研究煤层H_(2)S与煤脱硫的协同治理,自制装置对复配碱液进行H_(2)S吸收和煤脱硫试验。采用离子色谱法、X射线光电子能谱、形态硫测试对吸收液和煤样进行表征,分析协同治理机理,利用响应面法分析各因素对H_(2)S吸收和煤脱硫的影响程度... 为研究煤层H_(2)S与煤脱硫的协同治理,自制装置对复配碱液进行H_(2)S吸收和煤脱硫试验。采用离子色谱法、X射线光电子能谱、形态硫测试对吸收液和煤样进行表征,分析协同治理机理,利用响应面法分析各因素对H_(2)S吸收和煤脱硫的影响程度。结果显示:单一碱液均可吸收H_(2)S,但脱硫效果微弱;添加NaClO后,协同治理效果显著且能避免H_(2)S二次逸散,其中NaOH+NaClO协同治理效果最优。在反应后,H_(2)S及煤中低价态硫噻吩、硫醇和硫醚减少,吸收液中SO_(4)^(2-)及煤中高价态硫(亚)砜增加,表明NaOH为元素硫歧化提供碱性条件,元素硫继而被NaClO氧化。NaOH质量浓度对H_(2)S吸收影响最大,NaClO质量浓度对煤脱硫影响最大,NaOH和NaClO交互对煤脱硫与H_(2)S吸收影响显著。利用Design-Expert软件确定最佳参数:NaOH质量浓度为54 g/L、NaClO质量浓度为54 g/L、温度为21.4℃。 展开更多
关键词 安全工程 煤炭脱硫 硫化氢吸收 碱性次氯酸钠溶液 响应面方法 最佳参数选择
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能量选择电磁防护方法理论与应用
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作者 刘培国 虎宁 《电波科学学报》 CSCD 北大核心 2024年第3期385-394,431,共11页
随着信息技术的发展,电磁空间逐渐成为国家重大公共基础设施及信息网络的基石。近年来,强电磁源生成技术加速发展,对电磁空间安全形成严重威胁,开展强电磁防护技术研究具有迫切的现实需求。能量选择防护方法是一种新型自适应强电磁防护... 随着信息技术的发展,电磁空间逐渐成为国家重大公共基础设施及信息网络的基石。近年来,强电磁源生成技术加速发展,对电磁空间安全形成严重威胁,开展强电磁防护技术研究具有迫切的现实需求。能量选择防护方法是一种新型自适应强电磁防护方法,突破了电子设备前门防护“能防”和“兼容”的难题,为强电磁防护提供了新的技术思路。本文对能量选择防护方法进行了系统综述,首先详细介绍了能量选择防护的内涵和相关概念;其次以能量选择表面为例阐述了其工作原理与实现方式,在此基础上对能量选择防护方法的研究现状和最新成果进行介绍,梳理了能量选择防护方法的发展脉络;最后,对能量选择防护方法的未来研究方向进行了展望。 展开更多
关键词 电磁安全 强电磁防护 前门防护 能量选择 自适应响应
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