Coverage Area and Fading Time of Surfactant-Amended Herbicidal Droplets on Cucurbitaceous Leaves

2016 ◽  
Vol 59 (3) ◽  
pp. 829-838 ◽  
Keyword(s):  
2018 ◽  
Vol 61 (6) ◽  
pp. 1881-1888
Author(s):  
Jeng-Liang Lin ◽  
Heping Zhu

Abstract. Understanding reactions of surfactant-amended droplets on difficult-to-wet weed surfaces could help develop application strategies to increase herbicide efficacy. Behaviors of herbicidal droplets containing different emulsifiable anti-evaporation spray adjuvants were investigated by characterizing 250 and 450 µm herbicidal droplet dispersion and fading time on cucurbitaceous leaves placed inside a 20°C chamber at 30% and 60% relative humidity (RH). Droplet maximum coverage area increased with droplet size but not with RH, while droplet fading time increased with both droplet size and RH. Despite 450 µm droplets having greater maximum coverage area than 250 µm droplets, the larger droplets had higher fading rates and lower ratios of maximum coverage area to droplet volume. Droplet maximum coverage area and fading time on leaves were affected by adding spray adjuvants to the herbicide-only solution. The Uptake surfactant was more effective than the other two surfactants (AntiEvap+BS1000 and Enhance) in increasing droplet maximum coverage area and fading time. Compared to the herbicide-only solution, addition of Uptake surfactant to the herbicide solution could increase maximum coverage area by 68% and 52% for 250 and 450 µm droplets, respectively, but addition of AntiEvap+BS1000 or Enhance surfactants did not show significant increase. Similarly, addition of Uptake surfactant to the herbicide-only solution increased droplet fading times by 11.1% and 13.2% at 30% and 60% RH, respectively, for 250 µm droplets and by 34.7% and 2.8% at 30% and 60% RH, respectively, for 450 µm droplets. In contrast, addition of AntiEvap+BS1000 surfactant reduced fading time, and addition of Enhance surfactant did not significantly affect fading time. Therefore, appropriate selection of spray adjuvants for herbicide applications could significantly influence droplet deposit behaviors on cucurbitaceous leaves, leading to improved effectiveness of weed control. Keywords: Herbicide application, Spray deposition, Spray droplet, Surfactant, Weed control.


2019 ◽  
Vol 35 (5) ◽  
pp. 713-721
Author(s):  
Jeng-Liang Lin ◽  
Heping Zhu ◽  
Peter Ling

Abstract.Improving the coverage area and fading time of herbicidal droplets on weeds has the potential to enhance the biological control effectiveness. Droplet spreading and fading behaviors on five different weeds were characterized for spray solutions containing a 1.25% glyphosphate Rodeo herbicide amended with each of three different adjuvants (nonionic surfactant Kinetic, nonionic organosilicone surfactant DyneAmic, and nonionic surfactant and antifoaming agent Preference). The five weeds were ragweed, crabgrass, yellow nutsedge, common purslane, and spurge. Tests were conducted by depositing single 300 and 600 µm herbicidal droplets with different adjuvant concentrations on weed leaves inside an environment control chamber. A droplet at a higher adjuvant concentration had greater coverage area on weed surfaces. Preference-amended herbicidal droplets had the largest coverage area increase for all five weeds, and generally followed by droplets with Kinetic and DyneAmic except for 300 µm droplet on purslane and 600 µm droplet on spurge. In comparison with the herbicidal solution containing Rodeo and water only, with addition of adjuvants the 600 µm droplets increased the coverage area by 2.13 to 5.47, 1.76 to 2.56, 1.84 to 2.07, and 2.40 to 4.49-fold on crabgrass, yellow nutsedge, common purslane, and spurge, respectively, while the 300 µm droplets increased the coverage area on ragweed by 3.88 to 5.86-fold. In contrast, fading times of all 300 µm droplets decreased with the adjuvant addition except for DyneAmic applied on purslane. However, fading times of 600 µm droplets did not have increase or decrease trends with adjuvants, which depended on types of the adjuvant and weed. The overall comparison by integrated index (coverage area × fading time) indicated that a spray droplet at higher adjuvant concentration was likely to have a higher integrated index. In addition, Preference amended droplets had significantly more integrated index increase for crabgrass and nutsedge, while DyneAmic had more increase for purslane. Therefore, appropriate selections of spray adjuvants during herbicide applications could significantly increase droplet deposition effectiveness for controlling specific weeds. Keywords: Spray droplet, Spray additive, Herbicide application, Surfactant, Weed control.


2017 ◽  
Vol 5 (1) ◽  
pp. 63
Author(s):  
Maria Ulfah
Keyword(s):  

Author(s):  
Agel Vidian Krama ◽  
Nurul Qamilah

Location Hospital and Health Center in Bandar Lampung and the District Pesawaran not currently mapped by conventional or digital. And there is no data base that provides information about the location and distribution of hospitals and health centers in Bandar Lampung City, and the uneven number of health facilities to ensure the availability of health services for all citizens, by optimizing existing health care facilities. Contributions utilization of spatial studies in the health field is used for mapping and modeling of health in order to facilitate access, provision of efficiency and planning of health services in order to take policy related to determining the location of health facilities. The research method uses spatial model approach with descriptive research type and analysis through the use of Huff Model. The results of the regionization shows the coverage area of hospital services serving 33 points in the District Pesawaran and 24 point Population in Bandar Lampung with the spread of regionization is divided into 3 regions. Keywords: Health Service, Regionalization


Author(s):  
A. Suresh Babu ◽  
B. Anand

: A Linear Feedback Shift Register (LFSR) considers a linear function typically an XOR operation of the previous state as an input to the current state. This paper describes in detail the recent Wireless Communication Systems (WCS) and techniques related to LFSR. Cryptographic methods and reconfigurable computing are two different applications used in the proposed shift register with improved speed and decreased power consumption. Comparing with the existing individual applications, the proposed shift register obtained >15 to <=45% of decreased power consumption with 30% of reduced coverage area. Hence this proposed low power high speed LFSR design suits for various low power high speed applications, for example wireless communication. The entire design architecture is simulated and verified in VHDL language. To synthesis a standard cell library of 0.7um CMOS is used. A custom design tool has been developed for measuring the power. From the results, it is obtained that the cryptographic efficiency is improved regarding time and complexity comparing with the existing algorithms. Hence, the proposed LFSR architecture can be used for any wireless applications due to parallel processing, multiple access and cryptographic methods.


2014 ◽  
Vol 8 (1) ◽  
pp. 668-674
Author(s):  
Junguo Zhang ◽  
Yutong Lei ◽  
Fantao Lin ◽  
Chen Chen

Wireless sensor networks composed of camera enabled source nodes can provide visual information of an area of interest, potentially enriching monitoring applications. The node deployment is one of the key issues in the application of wireless sensor networks. In this paper, we take the effective coverage and connectivity as the evaluation indices to analyze the effect of the perceivable angle and the ratio of communication radius and sensing radius for the deterministic circular deployment. Experimental results demonstrate that the effective coverage area of the triangle deployment is the largest when using the same number of nodes. When the nodes are deployed in the same monitoring area in the premise of ensuring connectivity, rhombus deployment is optimal when √2 < rc / rs < √3 . The research results of this paper provide an important reference for the deployment of the image sensor networks with the given parameters.


Author(s):  
Muhammad Danish Siddiqui ◽  
Arjumand Z Zaidi

<span>Seaweed is a marine plant or algae which has economic value in many parts of the world. The purpose of <span>this study is to evaluate different satellite sensors such as high-resolution WorldView-2 (WV2) satellite <span>data and Landsat 8 30-meter resolution satellite data for mapping seaweed resources along the coastal<br /><span>waters of Karachi. The continuous monitoring and mapping of this precious marine plant and their <span>breeding sites may not be very efficient and cost effective using traditional survey techniques. Remote <span>Sensing (RS) and Geographical Information System (GIS) can provide economical and more efficient <span>solutions for mapping and monitoring coastal resources quantitatively as well as qualitatively at both <span>temporal and spatial scales. Normalized Difference Vegetation Indices (NDVI) along with the image <span>enhancement techniques were used to delineate seaweed patches in the study area. The coverage area of <span>seaweed estimated with WV-2 and Landsat 8 are presented as GIS maps. A more precise area estimation <span>wasachieved with WV-2 data that shows 15.5Ha (0.155 Km<span>2<span>)of seaweed cover along Karachi coast that is <span>more representative of the field observed data. A much larger area wasestimated with Landsat 8 image <span>(71.28Ha or 0.7128 Km<span>2<span>) that was mainly due to the mixing of seaweed pixels with water pixels. The <span>WV-2 data, due to its better spatial resolution than Landsat 8, have proven to be more useful than Landsat<br /><span>8 in mapping seaweed patches</span></span></span></span></span></span></span></span></span></span></span></span></span></span><br /><br class="Apple-interchange-newline" /></span></span></span></span></span>


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1098.2-1099
Author(s):  
O. Russell ◽  
S. Lester ◽  
R. Black ◽  
C. Hill

Background:Socioeconomic status (SES) influences disease outcomes in rheumatoid arthritis (RA) patients. (1, 2) Differences in medication use could partly explain this association. (3) A scoping review was used to identify research conducted on this topic and determine what knowledge gaps remain.Objectives:To determine what research has been conducted on this topic, how this research has defined SES and medication use, and establish what knowledge gaps remain.Methods:MEDLINE, EMBASE and PsychInfo were searched from their inception until May 2019 for studies which assessed SES and medication use as outcome variables. Studies were included if they measured medication use and incorporated an SES measure as a comparator variable.SES was defined using any of the “PROGRESS” framework variables (4) including patients’ stated gender, age, educational attainment, employment, occupational class, personal income, marital status, health insurance coverage, area- (neighbourhood) level SES, or patients’ stated race and/or ethnicity. Medication use was broadly defined as either prescription or dispensation of a medicine, medication adherence, or delays in treatment. Data was extracted on studies’ primary objectives, measurement of specific SES measures, patients’ medication use, and whether studies assessed for differences in patients’ medication use according to SES variables.Results:1464 studies were identified by this search from which 74 studies were selected for inclusion, including 52 published articles. Studies’ publication year ranged from 1994-2019, and originated from 20 countries; most commonly from the USA.Studies measured a median of 4 SES variables (IQR 3-6), with educational achievement, area level SES and race/ethnicity the most frequently recorded.Likelihood of disease modifying antirheumatic drug (DMARD) prescription was the most frequent primary objective recorded.96% of studies reported on patients’ use of DMARDs, with glucocorticoids and analgesics being reported in fewer studies (51% and 23% respectively.)Most included studies found at least one SES measure to be significantly associated with differences in patients’ medication use. In some studies, however, this result was not necessarily drawn from the primary outcome and therefore may not have been adjusted for covariates.70% of published studies measuring patients’ income (n=14 of 20) and 58% of those that measured race/ethnicity (n=14 of 24) documented significant differences in patients’ medication use according to these SES variables, although the direction of this effect – whether it led to ‘greater’ or ‘lesser’ medication use – varied between studies.Conclusion:Multiple definitions of SES are used in studies of medication use in RA patients. Despite this, most identified studies found evidence of a difference in medication use by patient groups that differed by an SES variable, although how medication use differed was found to vary between studies. This latter observation may relate to contextual factors pertaining to differences in countries’ healthcare systems. Further prospective studies with clearly defined SES and medication use measures may help confirm the apparent association between SES and differences in medication use.References:[1]Jacobi CE, Mol GD, Boshuizen HC, Rupp I, Dinant HJ, Van Den Bos GA. Impact of socioeconomic status on the course of rheumatoid arthritis and on related use of health care services. Arthritis Rheum. 2003;49(4):567-73.[2]ERAS Study Group. Socioeconomic deprivation and rheumatoid disease: what lessons for the health service? ERAS Study Group. Early Rheumatoid Arthritis Study. Annals of the rheumatic diseases. 2000;59(10):794-9.[3]Verstappen SMM. The impact of socio-economic status in rheumatoid arthritis. Rheumatology (Oxford). 2017;56(7):1051-2.[4]O’Neill J, Tabish H, Welch V, Petticrew M, Pottie K, Clarke M, et al. Applying an equity lens to interventions: using PROGRESS ensures consideration of socially stratifying factors to illuminate inequities in health. J Clin Epidemiol. 2014;67(1):56-64.Acknowledgements:This research was supported by an Australian Government Research Training Program Scholarship.Disclosure of Interests:None declared


2021 ◽  
Vol 13 (5) ◽  
pp. 939
Author(s):  
Yongan Xue ◽  
Jinling Zhao ◽  
Mingmei Zhang

To accurately extract cultivated land boundaries based on high-resolution remote sensing imagery, an improved watershed segmentation algorithm was proposed herein based on a combination of pre- and post-improvement procedures. Image contrast enhancement was used as the pre-improvement, while the color distance of the Commission Internationale de l´Eclairage (CIE) color space, including the Lab and Luv, was used as the regional similarity measure for region merging as the post-improvement. Furthermore, the area relative error criterion (δA), the pixel quantity error criterion (δP), and the consistency criterion (Khat) were used for evaluating the image segmentation accuracy. The region merging in Red–Green–Blue (RGB) color space was selected to compare the proposed algorithm by extracting cultivated land boundaries. The validation experiments were performed using a subset of Chinese Gaofen-2 (GF-2) remote sensing image with a coverage area of 0.12 km2. The results showed the following: (1) The contrast-enhanced image exhibited an obvious gain in terms of improving the image segmentation effect and time efficiency using the improved algorithm. The time efficiency increased by 10.31%, 60.00%, and 40.28%, respectively, in the RGB, Lab, and Luv color spaces. (2) The optimal segmentation and merging scale parameters in the RGB, Lab, and Luv color spaces were C for minimum areas of 2000, 1900, and 2000, and D for a color difference of 1000, 40, and 40. (3) The algorithm improved the time efficiency of cultivated land boundary extraction in the Lab and Luv color spaces by 35.16% and 29.58%, respectively, compared to the RGB color space. The extraction accuracy was compared to the RGB color space using the δA, δP, and Khat, that were improved by 76.92%, 62.01%, and 16.83%, respectively, in the Lab color space, while they were 55.79%, 49.67%, and 13.42% in the Luv color space. (4) Through the visual comparison, time efficiency, and segmentation accuracy, the comprehensive extraction effect using the proposed algorithm was obviously better than that of RGB color-based space algorithm. The established accuracy evaluation indicators were also proven to be consistent with the visual evaluation. (5) The proposed method has a satisfying transferability by a wider test area with a coverage area of 1 km2. In addition, the proposed method, based on the image contrast enhancement, was to perform the region merging in the CIE color space according to the simulated immersion watershed segmentation results. It is a useful attempt for the watershed segmentation algorithm to extract cultivated land boundaries, which provides a reference for enhancing the watershed algorithm.


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