Timing Application Research Articles

Offline supervisory control synthesis: taxonomy and recent developments

This paper surveys recent advances in supervisory control theory since its 30th anniversary in 2017. We performed a systematic literature search and selected 272 relevant papers, with a focus on automata-based approaches. These were fitted into coherent narratives, based in part on a taxonomy of supervisor synthesis methods. The obtained papers show the fast and vast progress of the field, where recent research covers a wide range of new synthesis optimization techniques, different aspects such as fault tolerance, security, and timing, and new and diverse application domains. This survey refrains from in-depth descriptions of techniques, instead focusing on high-level contributions of recent works, how they relate to each other, and future directions for research.

Responses of N2O, CO2, and NH3 Emissions to Biochar and Nitrification Inhibitors Under a Delayed Nitrogen Application Regime

Greenhouse gas and NH3 emissions are exacerbated by the inappropriate timing and excessive application of nitrogen (N) fertilizers in wheat cultivation in China. In this study, the impacts on N2O, CO2, and NH3 emissions of a delayed and reduced N application regime on the Huang-Huai-Hai Plain were investigated. The treatments comprised the control (N0), conventional N at 270 kg N ha−1 (N270) and optimized N application of 180 kg N ha−1 (N180), N180 + biochar at 7.5 t ha−1 (N180B7.5), N180 + biochar at 15 t ha−1 (N180B15), N180 + DMPP (a nitrification inhibitor; N180D), N180D + biochar at 7.5 t ha−1 (N180DB7.5), and N180D + biochar at 15 t ha−1 (N180DB15). Reduced N application (N180) lowered N2O and NH3 emissions. Biochar application resulted in a 4–25% and 12–16% increase in N2O and NH3 emissions, respectively. Application of DMPP significantly decreased N2O emissions by 32% while concurrently inducing a 9% increase in NH3 emissions. Co-application of DMPP and biochar significantly reduced the activity of nitrification enzymes (HAD, NOO), resulting in a reduction of 37–38% in N2O emissions and 13–14% in NH3 emissions. No significant differences in CO2 emissions were observed among the various N treatments except the N0 treatment. Application of DMPP alone did not significantly affect grain yield. However, biochar, in combination with DMPP, effectively increases grain yield. The findings suggest that the N180DB15 treatment has the potential to reduce emissions of N2O and NH3 while concurrently enhancing soil fertility (pH, SOC) and wheat yield.

CNN-LSTM Base Station Traffic Prediction Based On Dual Attention Mechanism and Timing Application

Abstract Energy consumption in 5G base stations remains consistently high, even during periods of low traffic loads, thereby resulting in unnecessary inefficiencies. To address this problem, this paper presents a novel approach by proposing a convolutional neural network (CNN)-long short-term memory (LSTM) traffic prediction model with a dual attention mechanism, coupled with the particle swarm optimization k-means algorithm for intelligent switch timing. The proposed CNN-LSTM model leverages a dual channel attention mechanism to bolster key feature information for long-term traffic data predictions. Specifically, a temporal attention mechanism is added to the LSTM to enhance the importance of temporal information. Moreover, the particle swarm optimization K-Means algorithm is proposed in order to cluster the traffic prediction results, output the corresponding time points of the lower traffic value and to obtain the optimal switch-off periods of the base station. Extensive experiments across multiple base stations over an extended period of time have validated our approach. The results show that this method offers accurate traffic prediction with minimal average errors in traffic prediction and the on/off timings of the base stations are in line with the “tide effect” of traffic, thereby achieving the goal of energy savings.

Previous crop and herbicide timing application effects on weed population growth rate

AbstractA well‐designed crop rotation can create an unstable environment that disrupts weed population growth rates. In combination with effective herbicide programs, growers may maintain weed populations at levels below competitive and economic thresholds. The objectives of the present study were to evaluate how the preceding rotational crop determines the response of weed populations to in‐season postemergence herbicide programs and the weed population density of the following crop season. The first‐year crop treatments were corn (Zea mays L.), cotton (Gossypium hirsutum L.), peanut (Arachis hypogaea L.), grain sorghum [Sorghum bicolor (L.) Moench.], and soybean [Glycine max (L.) Merr.]. In the second year, all plots were planted with cotton, and herbicide treatments were single applications 2 or 6 weeks after planting (WAP), two sequential applications 2 and 4 or 4 and 6 WAP, three sequential applications 2, 4, and 6 WAP, and a weedy control without herbicides was included. In the absence of herbicides, corn had the lowest population growth rates for broadleaf weeds (λ = 0.8) while peanut and grain sorghum had the highest (λ = 1.7 and 1.3, respectively). The results indicated that herbicide applications focused exclusively on preventing yield loss may not be sufficient to ensure weed population reductions. Thus, the observed population growth rates (λ = 2 for grassy weeds and λ = 1.26 for broadleaved weeds) indicated that weed issues would continue increasing, despite meeting yield goals. Considering population growth rates when assessing weed management strategies is key to determining the sustainability of the crop production operation.

T-RAIM Approaches: Testing with Galileo Measurements.

Several applications rely on time retrieved from Global Navigation Satellite System (GNSS), and this pushes for integrity tailored to timing. Integrity information could be broadcast by GNSS itself, but currently, there are no GNSSs providing such integrity information for a timing application. The integrity provided by GNSS itself could not be timely enough for real time users and does not include local effects due to multipath or other local interferences. In order to fill the gap, integrity can be locally/autonomously computed by the receiver using Timing Receiver Autonomous Integrity Monitoring (T-RAIM) algorithms. Three T-RAIM algorithms have been designed, implemented, and tested; specifically, the algorithms are Forward-Backward (FB), Danish, and Subset. The algorithms are applied to the classical Position Velocity and Timing (PVT) solution and to the time-only case assuming the receiver coordinates are known. Tests using two identical receivers located in different scenarios, open-sky and obstructed, have been carried out to validate the algorithms proposed. The increased redundancy obtained from the knowledge of the receiver coordinates play a fundamental role for the integrity algorithms performance. The benefits of the T-RAIM algorithms activation, in signal degraded conditions, clearly emerged in terms of frequency error and Allan Deviation (ADEV). A small increase of the execution time has been observed when the T-RAIM algorithms are used.

Energy-Barycenter Based Waveform Centroid Algorithm for Pulse Lidar Ranging System

This paper proposes an energy-barycenter-based waveform centroid algorithm (EWCA) for a high-precision Lidar ranging system. Firstly, the emission and echo pulse models of the pulse Lidar ranging system are established. Secondly, based on analyzing the merits and demerits of the conventional waveform centroid algorithm (CWCA) and intensity-weighted waveform centroid discrimination algorithm (IWCD). Moreover, combined with the characteristics of the energy moment distribution, the adaptive strategy is used to select the point with the higher signal as the calculation time series, and we proposed the EWCA to calculate the timing moment. Finally, we compared EWCA with CWCA and IWCD through simulation and actual experiments. The experimental simulation results show EWCA has higher accuracy and robustness than the comparison algorithm with different SNR. EWCA can achieve an average error of 0.1235 ns, a standard deviation of 0.0848 ns, and variance of 0.0072 ns at an SNR of 5 dB. At the same time, the Lidar ranging system is established to compare these methods further, and the ranging error of the proposed method can be within 20 mm when the measured distance is 40 m. This method has higher timing accuracy and application range, which has the potential to handle further ranging tasks.

Effects of timing and nitrogen fertilizer application rates on maize yield components and yield in eastern Ethiopia

AbstractMaize (Zea mays L.) is an important food security crop in Ethiopia. However, low soil fertility and the use of haphazard nitrogen (N) fertilizer with little attention to the rate and timing of N application constrain productivity. Therefore, field experiments were conducted during the 2019 and 2020 cropping seasons to investigate the response of maize to different N application rates and timings. The treatments consisted of six N fertilizer rates (0, 23, 46, 69, 92, and 115 kg N ha−1) and four application timings (all at vegetative stages; one‐half at sowing + one‐half at vegetative stages; one‐third at sowing + one‐third at vegetative stages + one‐third at tasseling; one‐fourth at sowing + two‐fourths at vegetative stages + one‐fourth at tasseling). The experiments were a randomized block design in a factorial arrangement with three replications. The results of the study revealed that ears per plant, ear length, grains per row, grains per ear, stover, and grain yield were significantly (p ≤ .001) influenced by the interaction effects of N application rates and timings. The highest stover (9.99 t ha−1) and grain yield (9.41 t ha−1) were obtained from the application of 92 kg N ha−1 in three split applications of one‐fourth at sowing, one‐half at vegetative stages, and one‐fourth at tasseling. Therefore, it is concluded that 92 kg N ha−1 in three split applications of one‐fourth at sowing, two‐fourths at vegetative stages, and one‐fourth at tasseling was found to be the most economical in the study area.

RESPONSE OF SOME LEGUMINOUS PLANTS TO SPECIFIC RHIZOBIAL INOCULATION TIMING WITHIN GERMINATION STAGE

The present work was conducted to: a) Evaluation the effect of some abiotic stress tolerance of the specific rhizobial strains and its phenotypic characterization. b) Evaluation the effect of the timing application of the specific rhizobial liquid inoculationto some leguminous plants on the nodulation process. c) Evaluation the response of some hybrids of the same leguminous plants to the timing application of its specific rhizobial liquid inoculation., and d) Reflection between the response of some leguminous plants and their hybrids to the timing application of its specific rhizobial liquid inoculation on the plant growth and crop quality. To select the most three efficient strains to employed in the field experiment. Some specific rhizobial strains were subjected to some abiotic stress tolerance and its phenotypic characterization. Antibiotics, temperature, salt (NaCl) lead (Pb) and sodium azide tolerance, IAA, exopolysaccharides (EPS), were determined, as well as morpho-cultural characterization (Gram staining, colony size, shape, border, elevation, color, mucosity, transparency, scanning electron micro graph of the same tested specific rhizobial strains, were performed. Three field experiments were conducted at the same site at Om Saber Village-Tahrir regions - Beheira Governorate, Egypt (Latitude 30o.40´N- Longitude 30o.33´E) (sandy soils presented newly reclaimed soil). The first, second and third experiments were carried out on soybean (Glycine max), common beanplants (Phaseolus vulgarisL.) and peanut (Arachis hypogaea L.), respectively. Each experiment was carried using two cultivars of the cultivated leguminous plants. These treatment of each experiments were complete randomized block plot design. The planting dates were at 15 April and 15 Mai, 1st September 2019 and for Soybean, common and peanut bean plants, respectively.

Misuse, perceived risk, and safety issues of household insecticides: Qualitative findings from focus groups in Arequipa, Peru.

BackgroundThe current body of research on insecticide use in Peru deals primarily with application of insecticides offered through Ministry of Health-led campaigns against vector-borne disease. However, there is a gap in the literature regarding the individual use, choice and perceptions of insecticides which may influence uptake of public health-based vector control initiatives and contribute to the thousands of deaths annually from acute pesticide poisoning in Peru.MethodsResidents (n = 49) of the Alto Selva Alegre and CC districts of peri-urban Arequipa participated in seven focus group discussions (FGD). Using a FGD guide, two facilitators led the discussion and conducted a role-playing activity. this activity, participants insecticides (represented by printed photos of insecticides available locally) and pretended to “sell” the insecticides to other participants, including describing their qualities as though they were advertising the insecticide. The exercise was designed to elicit perceptions of currently available insecticides. The focus groups also included questions about participants’ preferences, use and experiences related to insecticides outside the context of this activity. Focus group content was transcribed, and qualitative data were analyzed with Atlas.ti and coded using an inductive process to generate major themes related to use and choice of insecticides, and perceived risks associated with insecticide use.ResultsThe perceived risks associated with insecticides included both short- and long-term health impacts, and safety for children emerged as a priority. However, in some cases insecticides were reportedly applied in high-risk ways including application of insecticides directly to children and bedding. Some participants attempted to reduce the risk of insecticide use with informal, potentially ineffective personal protective equipment and by timing application when household members were away. Valued insecticide characteristics, such as strength and effectiveness, were often associated with negative characteristics such as odor and health impacts. “Agropecuarios” (agricultural supply stores) were considered a trusted source of information about insecticides and their health risks.ConclusionsIt is crucial to characterize misuse and perceptions of health impacts and risks of insecticides at the local level, as well as to find common themes and patterns across populations to inform national and regional programs to prevent acute insecticide poisoning and increase community participation in insecticide-based vector control campaigns. We detected risky practices and beliefs about personal protective equipment, risk indicators, and safety levels that could inform such preventive campaigns, as well as trusted information sources such as agricultural stores for partnerships in disseminating information.

Effect of supplemental irrigation timing and potassium fertilizer on rain-fed fig in micro-catchment: yield and yield quality

In this study, the effect of supplemental irrigation timing (treatments included no supplemental irrigation; supplemental irrigation in middle of March; supplemental irrigation in early May; supplemental irrigation in early August; and two supplemental irrigation events in middle of March and early May) and potassium (K) application (treatments included no-fertilizer; 150 and 250 g fertilizer per tree applied by fertigation method and no-fertilizer; 1.5 and 3.0 kg fertilizer per 1000 L water used by foliar application) on yield and yield quality of rain-fed fig trees were studied at the Estahban fig orchards in Fars province, Iran, through a three-year experiment. Results showed that supplemental irrigation for fig resulted in an increase in yield and fruit size, and improved the fruit peel color. However, it decreased total soluble solid of fruit. For one irrigation during the growing season, irrigation in late winter (March) with 1250 L of applied water per tree was better than irrigation in spring (May) with a similar amount applied water which was used as the supplemental irrigation of rain-fed fig trees under severe drought conditions. Two irrigation in March and May with 1500 L and 1250 L of applied water per tree for each event for the first year and two subsequent years, respectively, was more effective on the yield and fruit quality than single irrigation due to higher applied irrigation water. Using 150 g K per tree by fertigation method or 3.0 kg/1000L foliar K fertilizer resulted in significant effect on the yield and yield quality of fig and improved them.

Mathematical modeling of intervention and low medical resource availability with delays: Applications to COVID-19 outbreaks in Spain and Italy.

Infectious diseases have been one of the major causes of human mortality, and mathematical models have been playing significant roles in understanding the spread mechanism and controlling contagious diseases. In this paper, we propose a delayed SEIR epidemic model with intervention strategies and recovery under the low availability of resources. Non-delayed and delayed models both possess two equilibria: the disease-free equilibrium and the endemic equilibrium. When the basic reproduction number $ R_0 = 1 $, the non-delayed system undergoes a transcritical bifurcation. For the delayed system, we incorporate two important time delays: $ \tau_1 $ represents the latent period of the intervention strategies, and $ \tau_2 $ represents the period for curing the infected individuals. Time delays change the system dynamics via Hopf-bifurcation and oscillations. The direction and stability of delay induced Hopf-bifurcation are established using normal form theory and center manifold theorem. Furthermore, we rigorously prove that local Hopf bifurcation implies global Hopf bifurcation. Stability switching curves and crossing directions are analyzed on the two delay parameter plane, which allows both delays varying simultaneously. Numerical results demonstrate that by increasing the intervention strength, the infection level decays; by increasing the limitation of treatment, the infection level increases. Our quantitative observations can be useful for exploring the relative importance of intervention and medical resources. As a timing application, we parameterize the model for COVID-19 in Spain and Italy. With strict intervention policies, the infection numbers would have been greatly reduced in the early phase of COVID-19 in Spain and Italy. We also show that reducing the time delays in intervention and recovery would have decreased the total number of cases in the early phase of COVID-19 in Spain and Italy. Our work highlights the necessity to consider the time delays in intervention and recovery in an epidemic model.

Influence of fertilizer application timing and reduced herbicide dosage on weed infestation and maize grain yield

A field trial was conducted in the southern Guinea savanna of Nigeria during 2018 and 2019 to determine the better time of fertilizer application and identify effective weed management options to manage weed infestation and increase maize grain yield. The treatments consisted of two fertilizer application timings and six weed control treatments. The experiment was a 2 x 6 factorial in a randomized complete block design and replicated three times. The fertilizer application at 0 and 6 weeks after seeding (WAS) was found better than application at 2 and 6 WAS in minimising weeds, however both the application timings had no significant influence on maize grain yield. The formulated ready-mixtures (RM) of metolachlor (373 g) + atrazine (375 g) at 1.5 kg/ha followed by (fb) one hoeing at 6 WAS, metolachlor (375 g) + atrazine (373 g) at 1.5 kg/ha fb nicosulfuron 0.03 kg/ha at 6 WAS, metolachlor + atrazine (RM) 1.5 kg/ha fb paraquat 0.7 kg/ha at 6 WAS and metolachlor + atrazine (RM) at 1.5 kg/ha fb 2,4-D (900 g) at 1.5 kg/ha significantly (p=0.05) reduced weed infestation by 89.3, 63.8, 48.2 and 39.8%, respectively. The use of metolachlor + atrazine (RM) 1.5 kg/ha fb one hoeing at 6 WAS, metolachlor + atrazine (RM) 1.5 kg fb nicosulfuron 0.03 kg/ha increased maize grain yield by 82.5 and 69.7%, respectively. These treatment combinations integrated with fertilizer timing application at 0 and 6 WAS may be used for efficient, economical and more eco-friendly management of weeds for increasing maize grain yield.

Effectiveness of Indaziflam and Glyphosate Tank Mix to Control Weed in Mature Oil Palm

Tank mixing of pre and post emergence herbicides with proper timing application is one potential way to reduce the rotation of herbicide application per year. An experiment was conducted in the field of 10 years old mature oil palm using the mixture of indaziflam 50 - 150 g a.i./ha and glyphosate 135 g a.i./ha. The standard herbicide used in the estate (mixture of methyl-metsulfuron 10 g a.i/ha and glyphosate 135 g a.i./ha) was used as a comparison. The experiment was designed by randomized block of 6 treatments and 4 repetitions. Herbicides were applied in rotation based on the designed timetable following field condition and certain policy in the estate. Indaziflam had shown its ability to suppress the growth of weed up to 9 months after application, just by the lowest dosage of 50 g b.a./ha. Indaziflam is safe to be used in the plantation as it showed no toxic nor negative effects to the oil palm. The mixture of indaziflam and standard herbicide have also reduced the rotation of herbicide application to twice a year.

Modeling and assessment of real-time precise point positioning timing with multi-GNSS observations

Real-time precise point positioning (PPP) method is of great interest for global navigation satellite systems (GNSS) time application with multi-GNSS observations. In this study, a multi-GNSS precise timing approach using Centre National d’Etudes Spatiales (CNES) real-time products was presented to improve the reliable of precise timing. Users can obtain the difference between the local time (time of rover receiver) and UTC(k) directly using a GNSS receiver, once the CNES products are aligned to UTC(k) by a multi-GNSS PPP approach. In other words, the reference times of the realigned products for GPS, GLONASS, BDS-2 and Galileo are UTC (k). Then, users can obtain the difference between the local time and UTC(k) directly using any single-system or multi-GNSS combination. Note that the receiver hardware delay needs to be calibrated before timing application. Numerical analyses clarify how the multi-GNSS precise timing approach performs. First, the standard deviation (STD) of the difference between the multi-GNSS timing results and the clock difference from the IGS final products is shown to be less than 0.5 ns. The multi-GNSS solutions outperform that of a single system. Furthermore, GPS-only PPP timing solutions perform better than that of GLONASS and Galileo-only. In addition, the maximum reductions of STD values are up to 33.6%, 11.6%, 14.6%, 25.6% for GPS-only, GLONASS-only, Galileo-only and multi-GNSS timing, respectively, using a receiver clock model. Second, the frequency stability of the multi-GNSS scheme is slightly better than GPS-only. For single-system PPP timing, GLONASS-only performs worst, while GPS-only performs best. The maximum improvements of frequency stability are up to 61.9%, 67.1%, 90.6%, 65.8% for GPS-only, GLONASS-only, Galileo-only and multi-GNSS timing, respectively, with a receiver clock model using the realigned products. More interestingly, we found that the performance Galileo-only was improved with the observations on 2019 as compared to Galileo with the observations on 2018.

Impacts of lower‐leaf removal timing, number, and nitrogen application to flue‐cured tobacco

AbstractThe removal and exclusion of lower‐stalk tobacco (Nicotiana tobacum L.) from harvest continues to be encouraged by industry. Very little information addresses the timing aspect of leaf removal, specifically when it occurs near floral initiation. Research was conducted in 2016 and 2017 to evaluate each possible treatment combination of two lower‐leaf removal programs (0 and 8 leaves/plant), three removal timings (2 wk before topping, at topping, and 2 wk after topping), and two N application rates (0 and 10 lb/ac). Soil plant analysis development (SPAD) measurements consistently revealed a lighter leaf color in treatments consisting of leaf removal 2 wk before topping, regardless of N application rate. Foliar cured leaf samples from upper‐stalk positions also contained less total N when eight leaves (2.25%) were removed relative to zero leaves (2.32%). These results indicate that subsequent N fertilizer application did not supply N as efficiently as remobilization from lower, older leaves. In the 8‐leaf removal program, both cured leaf yield and value declined by 27% relative to the 0‐leaf program. Despite significant losses in yield and value, the 8‐leaf program completely eliminated lug grades of tobacco. Leaf removal timing and N application rate did not affect yield, quality, value, or grade distribution. Our results suggest that there is no agronomic or cost to removing lower leaves 2 wk before or after topping; however, commercial farmers may find this information to be of use from a time management perspective, should they decide to implement this practice.

Effects of pesticides on farmers’ health in Tu Ky district, Hai Duong province, Vietnam

The survey on 300 farming households in Tu Ky district, Hai Duong province, Vietnam show that their knowledge about plant protection drugs is still very limited. Farmers do not understand the meaning of the colors and the contours on the packaging. The treatment of excess drugs and hygiene activities after pesticide application show that farmers' awareness is not high, thereby leading to environmental pollution and reduction in the physical health of farmers. The results about the effects of pesticides and herbicides on the health of farmers in Tu Ky district show that farmers often suffer from diseases such as eyes, ears, nose, and throat diseases, skin diseases, and gastrointestinal disorders. The proportion of farmers suffering from common diseases in communes specializing in vegetable production is higher than that of communes specializing in rice production. In particular, the proportions of deaths from cancer in Hung Dao and Ngoc Ky communes were 48.5% and 43.6%, respectively, much higher than that of An Thanh Commune (7.9%). In addition to the number of farmers and the high incidence of cancer deaths in the vegetable production area is compared to those in rice production area. COI of households at Hung Dao is 7,493 thousand VND (318 USD) and 5,996 thousand VND (255 USD) as compared to 1,742 thousand VND (74 USD) of An Thanh; The relative number is an increase of 340% - 430% compared to the pure rice production commune. This study aims to analyze and evaluate the types of pesticides, dosage, preparation method, timing, spraying time and behaviors after spraying of rice producers (An Thanh) and vegetable producers in Ngoc Ky and Hung Dao; The study results point out and confirm the special role of management, usage instructions, enhancement of production knowledge, types of drugs used, and non-used drugs and spraying tools, especially for vegetable production areas. For vegetable production areas, it is necessary to plan separate production areas for each type of vegetables, not intercropping vegetables, to provide detailed guidance on the specific type of drugs, the dosage, the time, timing, frequency, and pesticide application method for each type of vegetables. It is also of importance for farmers not to use pesticides leftover of this type of vegetable to other types of vegetables or spray the field borders. Vegetables are usually processed and consumed immediately, which means the time of delivery to consumers is very short, so it is important to help farmers fully understand the degree of negative impact on not only themselves, producers, but also on consumers, on society in the short run and in the long run. Producers and consumers even pay for their lives when using plant protection drugs, using agricultural products, especially vegetables. Health insurance is an important method of sharing disease risks of farmers in general and vegetable producers in particular.

3D Diamond Tracking Detectors: numerical analysis for Timing applications with TCAD tools

In view of the HL-LHC upgrade the use of Chemical Vapor Deposited (CVD) diamond has been proposed as an efficient alternative to conventional silicon-based devices. Diamond detectors are more robust to radiation damage, since the high carriers' mobility allows faster signal collection when compared to silicon, while retaining extremely low leakage currents. These properties could be of particular interest in particle detection applications where stringent timing and radiation tolerance requirements need to be fulfilled. A suitable implementation of such a class of detector is that of 3D pixelated CVD diamond with graphitic parallel columns/trenches contact scheme, fabricated through a focused laser beam technology. TCAD simulations can be exploited to assess the effect of different electrode configurations and/or biasing scheme on the electric field profiles, aiming at minimizing the effects of inefficient field regions in terms of charge collection. For timing application purposes, the transport effects along the graphitic columns can be accounted for, aiming at evaluating the performance and limitations of such a class of detectors. The equivalent “load” effect of graphitic columns of different size/resistivity can be taken into account by means of device/circuit-level simulations including measured resistances and capacitances.

Aging-Aware Instruction-Level Statistical Dynamic Timing Analysis for Embedded Processors

CMOS miniaturization and timing faults due to factors, such as aging, emphasize that embedded processor reliability is a major concern. Among the various aging mechanisms, negative bias temperature instability (NBTI) is encountered as the dominant factor. Techniques against NBTI are mostly based on aggressive $V_{\text {dd}}$ scaling, decelerating aging at the expense of performance degradation. Traditionally, designers use conservative guard-bands to combat timing faults, leading to loss of efficiency. Some other reactive approaches use sensors, requiring hardware modification and large area and debug overheads. According to the literature, two opportunities exist to compensate for the performance loss: instruction timing slacks imposed by static timing analysis (STA) and application computational error resiliency. This article proposes an efficient estimation model for the instruction-level timing slack probability distribution function (PDF) and gives a dynamic approach for statistical timing analysis, which is used for dynamic frequency management to improve performance of both error-resilient and error-sensitive applications. To this aim, we introduce a metric called architecture timing-fault vulnerability factor, considering NBTI and $V_{\text {dd}}$ effects. Simulation results show that the proposed timing slack PDF estimation model has an accuracy of about 94%, which can be used to increase throughput of error-resilient applications up to 3.2 times compared with when the traditional STA is used.

Novel timing application using microchannel plate with phosphor screen

A signal tapping circuit has been designed to derive the fast timing signal from the Chevron type, 2 stage MCP having phosphor screen as a readout device. Using this, the timing property of the MCP-BaF2 system has been studied using the digital storage oscilloscope in which a timing resolution of ~ 500 ps has been obtained. The applicability of MCP with phosphor screen configuration for timing measurements has been demonstrated.

Response of sweetpotato to pendimethalin application rate and timing

AbstractField trials were conducted near Pontotoc, Mississippi; Chase, Louisiana; and Clinton, North Carolina, in 2017 and 2018 to determine the effect of pendimethalin rate and timing application on sweetpotato crop tolerance, yield, and storage root quality. Treatments consisted of five pendimethalin rates (266, 532, 1,065, 1,597, and 2,130 g ai ha−1) by two application timings (0 to 1 or 10 to 14 d after transplanting). Additionally, a nontreated check was included for comparison. Crop injury (stunting) was minimal (≤4%) through 6 wk after transplanting (WAP) and no injury was observed from 8 to 14 WAP, regardless of application timing or rate. The nontreated check yielded 6.6, 17.6, 5.5, and 32.1 × 103 kg ha−1 of canner, no. 1, jumbo, and total grades, respectively. Neither pendimethalin application timing nor rate influenced jumbo, no. 1, marketable, or total sweetpotato yield. Overall, these results indicate that pendimethalin will be a valuable addition to the toolkit of sweetpotato growers.