Acibenzolar-S-methyl (ASM) is a chemical activator of systematic resistance in many plants. The effect of preharvest and postharvest application of ASM was evaluated for its ability to induce resistance in muskmelon...Acibenzolar-S-methyl (ASM) is a chemical activator of systematic resistance in many plants. The effect of preharvest and postharvest application of ASM was evaluated for its ability to induce resistance in muskmelon fruit. The results indicated that 50 and 100 mg L^-1 ASM or 1 mL L^-1 imazalil at 1 week or 1 day before harvest were effective in reducing the lesion area with 100 mg L^-1 ASM the most effective. No treatment inhibited the infection rate. The postharvest results showed that 50 and 100 mg L^-1 ASM, and 0.1 mL L^-1 imazalil were effective in reducing the lesion area with 100 mg L^-1 ASM the most effective. No treatment inhibited the infection rate. There was a clear time-dependent response of the fruit to postharvest ASM treatment, in which treatments applied 1, 3, and 5 day before inoculation provided the best results. ASM did not demonstrate any fungicide effect in vitro and suppressed lesion area in treated muskmelons, indicating that disease resistance was induced. The protection of ASM was associated with the activation of peroxidase (POD) in treated muskmelons.展开更多
针对驾驶员驾驶过程中因疲劳引起的眼睛开度变化问题,在原有PERCLOS(percentage of eyelid closure over the pupil over time)标准的基础上,提出了一种基于有限状态自动机的人眼开度PERCLOS计算方法,并将其应用到疲劳驾驶预警系统中。...针对驾驶员驾驶过程中因疲劳引起的眼睛开度变化问题,在原有PERCLOS(percentage of eyelid closure over the pupil over time)标准的基础上,提出了一种基于有限状态自动机的人眼开度PERCLOS计算方法,并将其应用到疲劳驾驶预警系统中。该系统首先采用红外摄像头实时获取驾驶员的脸部视频图像,使用ASM(active shape models)算法进行人脸检测,在定位到的人脸范围内搜索人眼区域并计算人眼开度,为了避免人与摄像头距离变化影响计算结果,对人眼开度进行归一化处理;然后依据建立的有限状态自动机模型计算PERCLOS值;最后根据制定的预警机制实现基于人眼开度的疲劳预警。实验结果表明本方法能够实时监测驾驶员疲劳状况,具有对光照变化、脸部配饰不敏感的特点。展开更多
In expression recognition, feature representation is critical for successful recognition since it contains distinctive information of expressions. In this paper, a new approach for representing facial expression featu...In expression recognition, feature representation is critical for successful recognition since it contains distinctive information of expressions. In this paper, a new approach for representing facial expression features is proposed with its objective to describe features in an effective and efficient way in order to improve the recognition performance. The method combines the facial action coding system(FACS) and 'uniform' local binary patterns(LBP) to represent facial expression features from coarse to fine. The facial feature regions are extracted by active shape models(ASM) based on FACS to obtain the gray-level texture. Then, LBP is used to represent expression features for enhancing the discriminant. A facial expression recognition system is developed based on this feature extraction method by using K nearest neighborhood(K-NN) classifier to recognize facial expressions. Finally, experiments are carried out to evaluate this feature extraction method. The significance of removing the unrelated facial regions and enhancing the discrimination ability of expression features in the recognition process is indicated by the results, in addition to its convenience.展开更多
The influence of soil moisture on Asian monsoon simulation/prediction was less studied, partly due to a lack of available and reliable soil moisture datasets. In this study, we firstly compare several soil moisture da...The influence of soil moisture on Asian monsoon simulation/prediction was less studied, partly due to a lack of available and reliable soil moisture datasets. In this study, we firstly compare several soil moisture datasets over the Tibetan Plateau, and find that the remote sensing products from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) can capture realistic temporal variations of soil moisture better than the two reanalyses (NCEP and ECMWF) during the pre-monsoon seasons. Using the AMSR-E soil moisture product, we investigate the impacts of soil moisture over the Tibetan Plateau on Asian summer monsoon onset based on a Spectral Atmospheric Model developed at IAP/LASG (SAMIL). Comparison between results with and without the assimilation of remotely sensed soil moisture data demonstrates that with soil moisture assimilated into SAMIL, the land-sea thermal contrast during pre-monsoon seasons is more realistic. Accordingly, the simulation of summer monsoon onset dates over both the Bay of Bengal and South China Sea regions are more accurate with AMSR-E soil moisture assimilated. This study reveals that the application of the soil moisture remote sensing products in a numerical model could potentially improve prediction of the Asian summer monsoon onset.展开更多
文摘Acibenzolar-S-methyl (ASM) is a chemical activator of systematic resistance in many plants. The effect of preharvest and postharvest application of ASM was evaluated for its ability to induce resistance in muskmelon fruit. The results indicated that 50 and 100 mg L^-1 ASM or 1 mL L^-1 imazalil at 1 week or 1 day before harvest were effective in reducing the lesion area with 100 mg L^-1 ASM the most effective. No treatment inhibited the infection rate. The postharvest results showed that 50 and 100 mg L^-1 ASM, and 0.1 mL L^-1 imazalil were effective in reducing the lesion area with 100 mg L^-1 ASM the most effective. No treatment inhibited the infection rate. There was a clear time-dependent response of the fruit to postharvest ASM treatment, in which treatments applied 1, 3, and 5 day before inoculation provided the best results. ASM did not demonstrate any fungicide effect in vitro and suppressed lesion area in treated muskmelons, indicating that disease resistance was induced. The protection of ASM was associated with the activation of peroxidase (POD) in treated muskmelons.
文摘针对驾驶员驾驶过程中因疲劳引起的眼睛开度变化问题,在原有PERCLOS(percentage of eyelid closure over the pupil over time)标准的基础上,提出了一种基于有限状态自动机的人眼开度PERCLOS计算方法,并将其应用到疲劳驾驶预警系统中。该系统首先采用红外摄像头实时获取驾驶员的脸部视频图像,使用ASM(active shape models)算法进行人脸检测,在定位到的人脸范围内搜索人眼区域并计算人眼开度,为了避免人与摄像头距离变化影响计算结果,对人眼开度进行归一化处理;然后依据建立的有限状态自动机模型计算PERCLOS值;最后根据制定的预警机制实现基于人眼开度的疲劳预警。实验结果表明本方法能够实时监测驾驶员疲劳状况,具有对光照变化、脸部配饰不敏感的特点。
基金supported by National Natural Science Foundation of China(No.61273339)
文摘In expression recognition, feature representation is critical for successful recognition since it contains distinctive information of expressions. In this paper, a new approach for representing facial expression features is proposed with its objective to describe features in an effective and efficient way in order to improve the recognition performance. The method combines the facial action coding system(FACS) and 'uniform' local binary patterns(LBP) to represent facial expression features from coarse to fine. The facial feature regions are extracted by active shape models(ASM) based on FACS to obtain the gray-level texture. Then, LBP is used to represent expression features for enhancing the discriminant. A facial expression recognition system is developed based on this feature extraction method by using K nearest neighborhood(K-NN) classifier to recognize facial expressions. Finally, experiments are carried out to evaluate this feature extraction method. The significance of removing the unrelated facial regions and enhancing the discrimination ability of expression features in the recognition process is indicated by the results, in addition to its convenience.
基金supported by the 973 Program of China (2006CB403607)the Chinese Academy of Sciences (ZKCX2-YW-Q11-04)+3 种基金the National Natural Science Foundation of China (40805038,40821092, 40890054)the National Science & Technology Pillar Program of China (2007BAC29B03)the Chinese Academy of Sciences (KZCX2-YW-Q11-04)LASG Free Exploration Fund
文摘The influence of soil moisture on Asian monsoon simulation/prediction was less studied, partly due to a lack of available and reliable soil moisture datasets. In this study, we firstly compare several soil moisture datasets over the Tibetan Plateau, and find that the remote sensing products from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) can capture realistic temporal variations of soil moisture better than the two reanalyses (NCEP and ECMWF) during the pre-monsoon seasons. Using the AMSR-E soil moisture product, we investigate the impacts of soil moisture over the Tibetan Plateau on Asian summer monsoon onset based on a Spectral Atmospheric Model developed at IAP/LASG (SAMIL). Comparison between results with and without the assimilation of remotely sensed soil moisture data demonstrates that with soil moisture assimilated into SAMIL, the land-sea thermal contrast during pre-monsoon seasons is more realistic. Accordingly, the simulation of summer monsoon onset dates over both the Bay of Bengal and South China Sea regions are more accurate with AMSR-E soil moisture assimilated. This study reveals that the application of the soil moisture remote sensing products in a numerical model could potentially improve prediction of the Asian summer monsoon onset.