scholarly journals Impact of missing sounding reports on mandatory levels and tropopause statistics: a case study

2006 ◽  
Vol 24 (10) ◽  
pp. 2445-2449 ◽  
Author(s):  
J. C. Antuña ◽  
J. A. Añel ◽  
L. Gimeno
Keyword(s):  
Time Lag ◽  
Mean Values ◽  
Transmission Problems ◽  
Mean Temperature ◽  
Complete Dataset ◽  
The Mean ◽  
Temperature And Pressure ◽  
Incomplete Datasets ◽  
Random Behaviour

Abstract. This paper describes the effect of missing sounding reports on temperature and pressure mean values for mandatory levels using the aerological information from the Camagüey Meteorological Centre. Also it is described the effect of missing data on mean temperature and pressure values at the multiple tropopause levels. The case study belongs to one station for a time lag of eight years. Up to the present these types of studies have been conducted using simulated datasets. The present one uses a real inhomogeneous radiosonde dataset. The main reason for missing reports were transmission problems and possible encoding-decoding difficulties. It has been found that profiles of the mean temperature and altitude show little differences between the complete and incomplete datasets. Moreover, no statistical significant differences were found for the mean values of the variables for the complete and incomplete datasets. The most probable reason for those results is that the cause of the missing reports has a random behaviour. Finally we have found that the only two effects noticed on the statistics were slightly higher values of the mean temperatures in the complete dataset and the decrease in the percent of multiple tropopause reports for the incomplete dataset.

Spontaneous Blinks as a Criterion of Visual Fatigue during Prolonged Work on Visual Display Terminals

2001 ◽  
Vol 92 (1) ◽  
pp. 234-250 ◽  
Author(s):  
Kenichi Kaneko ◽  
Kazuyoshi Sakamoto
Keyword(s):  
Time Lag ◽  
Vertical Direction ◽  
Visual Display ◽  
Hard Copy ◽  
Subjective Feeling ◽  
Visual Fatigue ◽  
Work Time ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean

Visual fatigue caused by prolonged work viewing a Visual Display Terminals (VDT) and of work reading a hard-copy were assessed by electromyogram (EMG) waveform and electrooculogram (EOG) waveform in spontaneous blinks as objective criteria, and by questionnaire of subjective feeling, and by task performance. The duration and the amplitude of the EMG of the orbicularis ocular muscle on the right side and the EOG of the vertical direction to the eyelid were measured for 10 subjects who participated in a figure task consisting of the addition of single-digit numbers on a VDT work or a work with a hard-copy. The mean values of the duration and the amplitude of the EMG and the EOG were evaluated by the averaging of 10 waveforms of the spontaneous blinks for all subjects. The time lag from the EMG to the EOG in the process of the generation of spontaneous blinks was also analyzed. These five parameters were evaluated during the work time. The mean values for the duration of the EMG increased gradually during the work time, but the amplitude did not show significant difference between the prework and a work time. There was no significant change of the duration of the EOG, but the mean amplitude of the EOG decreased as the work time progressed, and the time lag significantly extended. The blinks frequency increased relatively when using a VDT. The rate of fluctuation for these parameters was higher during use of a VDT than use of a hard-copy. The time lag at five hours of VDT work was extended by 90% based on the value at the prework. The symptoms of general fatigue and fatigue of the eyes increased linearly during the VDT work for six hours. The results indicated a significant correlation between the objective parameters for the activity of the spontaneous blinks, i.e., duration and amplitude of EMG and EOG, and the time lag between EMG and EOG, and the subjective feeling was recognized in the time course of the task. These experimental results suggested that the parameters regarding the EMG and the EOG for the spontaneous blinks were effective indices for assessing visual fatigue during prolonged VDT work.

scholarly journals Uncertainty in mass-balance trends derived from altimetry: a case study along the EGIG line, central Greenland

2015 ◽  
Vol 61 (226) ◽  
pp. 345-356 ◽  
Author(s):  
Elizabeth M. Morris ◽  
Duncan J. Wingham
Keyword(s):  
Mass Balance ◽  
Greenland Ice Sheet ◽  
Repeated Measurements ◽  
Elevation Change ◽  
Short Term ◽  
Density Profiles ◽  
Mean Values ◽  
Equivalent Mass ◽  
The Mean

AbstractRepeated measurements of density profiles and surface elevation along a 515 km traverse of the Greenland ice sheet are used to determine elevation change rates and the error in determining mass-balance trends from these rates which arises from short-term fluctuations in mass input, compaction and surface density. Mean values of this error, averaged over 100 km sections of the traverse, decrease with time from the start of observations in 2004, with a half-time of ∼4 years. After 7 years the mean error is less than the ice equivalent mass imbalance.

scholarly journals Using the “mean temperature of the catch” to assess fish community responses to warming in a temperate lake

2021 ◽  
Author(s):  
Külli Kangur ◽  
Erki Tammiksaar ◽  
Daniel Pauly
Keyword(s):  
Fish Community ◽  
Time Lag ◽  
Segmented Regression ◽  
Lake Peipsi ◽  
Data Set ◽  
Preferred Temperature ◽  
Catch Data ◽  
Mean Temperature ◽  
Fish Catch ◽  
The Mean

AbstractThis contribution applies the “mean temperature of the catch” (MTC) concept of Cheung et al. (Nature 497:365–368, 2013) to fish catch data for Lake Peipsi, Estonia/Russia, covering the years 1931 to 2019. The preferred temperature of each of the ten target fish species was obtained from the literature, and combined with the species-specific catch data to obtain MTC values for each year. The analysis of the MTC time series thus obtained with a segmented regression yielded two trend lines, one horizontal at 14.5 °C (1931–1986), and the other (1987–2019) ascending with a slope 0.85 °C·decade−1. Overall, the segmented regression model explains over half of the variance of the MTC data set (multiple R2 = 0.53; adjusted R2 = 0.51). Lake surface water temperatures correlate with MTC, even though weakly (r = 0.30), when considering a 2-year time lag. The fish community of the shallow Lake Peipsi reacts more strongly to temperature changes than marine ecosystems so far studied using the MTC.

scholarly journals Profiling students’ environmental care attitudes taught using Sasak Tribe local wisdom-integrated model

2019 ◽  
Vol 5 (3) ◽  
Author(s):  
H. Hunaepi ◽  
Ika Nuraini Dewi ◽  
S. Sumarjan
Keyword(s):  
Sampling Technique ◽  
Integrated Model ◽  
Descriptive Statistics ◽  
Central Tendency ◽  
Mean Values ◽  
Environmental Care ◽  
Descriptive Research ◽  
Analysis Technique ◽  
The Mean

Sasak Tribe possesses unique local wisdom which is potential to be utilized in term of improving students' care attitudes toward the environment. This study aimed at profiling students' evironmental attitudes who were taught using Sasak Tribe local wisdom-integrated model. This descriptive research was designed with a one-shot case study. The sample used in this study was 140 VII graders chosen using random sampling technique. The sample comprised of 3 classes of SMPN 2 Gunung Sari and 3 classes of SMPN 3 Lingsar placed in West Nusa Tenggara-Indonesia. The data analysis technique used was descriptive statistics in term of central tendency. The measured indicators were environmental awareness (EA), developing empathy (DE), and effect handling (EH). The results showed that the students live in suburb area tended to have better environmental care attitudes, in which the mean values were 86.66 (EA), 75.69 (DE), and 42.66 (EH) compared to those who live in urban area in which the mean values were 68.73 (EA), 57.07 (DE), and 30.62 (EH). Based on this findings, further evaluation in several aspects should be done.

An Investigation of the Lean Operational Limits of Gas-Fueled Spark Ignition Engines

1996 ◽  
Vol 118 (2) ◽  
pp. 159-163 ◽  
Author(s):  
O. A. Badr ◽  
N. Elsayed ◽  
G. A. Karim
Keyword(s):  
Spark Ignition ◽  
Spark Ignition Engines ◽  
Flammability Limit ◽  
Flammability Limits ◽  
Limit Values ◽  
Gaseous Fuels ◽  
Mean Temperature ◽  
Wide Range ◽  
The Mean ◽  
Temperature And Pressure

Examination is made of the operational limits in two variable compression-ratio single-cylinder engines when operating on the gaseous fuels methane, propane, LPG, and hydrogen under a wide range of conditions. Two definitions for the limits were employed. The first was associated with the first detectable misfire on leaning the mixture, while the second was the first detectable firing under motoring condition in the presence of a spark when the mixture was being enriched slowly. Attempts were also made to relate these limits to the corresponding values for quiescent conditions reckoned on the basis of the flammability limits evaluated at the mean temperature and pressure prevailing within the cylinder charge at the time of the spark. The measured limits in the engine were always higher than the corresponding flammability limit values for the three fuels. Both of these limits appear to correlate reasonably well with the calculated mean temperature of the mixture at the time of passing the spark.

scholarly journals Study of dissolve oxygen, salinity and temperature around western offshore- A case study around North Bombay of ONGC’s offshore Filed, Arabian Sea, India

2021 ◽  
Vol 02 (01) ◽  
pp. 091-100
Author(s):  
Rajkumar Mandal ◽  
Gada Lal Das
Keyword(s):  
Dissolve Oxygen ◽  
Arabian Sea ◽  
Preventive Measure ◽  
Biological Productivity ◽  
Mean Values ◽  
Environmental Status ◽  
Increasing Trend ◽  
Oil And Natural Gas ◽  
The Mean

Marine ecosystems cover approximately 71% of the Earth's surface and contain approximately 97% of the planet's water. Dissolve oxygen, which is a vital parameter in Ocean’s primary production, is having a sensitive integrating property reflecting physical and biogeochemical changes in the marine environment. The other parameters like temperature, though conservative, has a great impact upon biological productivity and salinity is important to understand the dynamics of water column. By analyzing the variation of dissolve oxygen, temperature and salinity, environmental status of that particular study area can be assessed. As a preventive measure to protect water bodies, Oil and Natural Gas Corporation Limited, India is regularly conducting Offshore Environment Monitoring around western continental shelf of Arabian Sea, where ONGC’s Platforms and Installations are located. The paper includes the output of monitoring activities of ONGC around north Bombay considering these three parameters i.e. temperature, salinity and dissolved oxygen for assessing the environmental health of the study area. A trend analysis of the three parameters around North Bombay of ONGC’s offshore Filed (NA & NQ platform) has been done considering the monitoring data from the year 2017-18 to 2020-21 and their variation has been studied. It has been observed from the study that there is an increasing trend of dissolve oxygen and salinity for both platform (NA & NQ). It is observed that trend of temperature for NA platform is decreasing whereas around NQ it is increasing. The mean values of three parameters are comparable with reference mean values and the variations are insignificant.

scholarly journals Case study of geochemical clustering as a tool for tracing sources of clays for archaeological and modern bricks

Baltica ◽  
2019 ◽  
Vol 32 (2) ◽  
pp. 139-155
Author(s):  
Ričardas Taraškevičius ◽  
Vaidotas Kazakauskas ◽  
Saulius Sarcevičius ◽  
Rimantė Zinkutė ◽  
Sergej Suzdalev
Keyword(s):  
Organic Matter ◽  
Hierarchical Clustering ◽  
Clay Material ◽  
Clustering Methods ◽  
Geochemical Composition ◽  
Complete Linkage ◽  
Mean Values ◽  
Pair Group ◽  
The Mean

The study was conducted using 14 hierarchical clustering ways and combining them with 4 inter-related sets of elements, i.e. the contents of Al, Ba, Ca, Fe, Ga, K, Mg, Mn, Na, Nb, P, Rb, Si, Sr, Th and Ti determined by EDXRF in 44 splits of 10 archaeological and 4 modern bricks, as well as in 38 clay samples from two quarries. Empirical scoring of tree dendrograms of archaeological samples helped to identify Complete Linkage, Weighted Pair Group Average and Ward’s methods as the most suitable for sourcing. Successful identification of geochemical clustering methods for fingerprinting sources of bricks is determined by the intrinsic features of the geochemical composition of stonework or quarries: their similarity, determined by the geochemical peculiarities of clay indicators, such as Al, Rb, Ga, K, Th, Fe, Ti and Nb, and differences, expressed by the elements that are more abundant in sands and silts (Si, Na), carbonates (Ca, Sr, Mg), organic matter (P) and other lithological-mineralogical tracers. It has been found that the mean values of the geochemical composition of the allied objects have much more useful fingerprinting properties. It is strongly recommended for source fingerprinting to select not only typical lithological-mineralogical samples, but also homogeneous sampling sets excluding possible outliers. It has been shown that each raw clay material has its own specific geochemical features. This is an essential useful feature for source fingerprinting using clustering of the objects of interest.

Perceived Benefits of Congestion Pricing for Trucks

2003 ◽  
Vol 1833 (1) ◽  
pp. 59-65 ◽  
Author(s):  
Kazuya Kawamura
Keyword(s):  
Congestion Pricing ◽  
Value Of Time ◽  
Perceived Benefits ◽  
Mean Values ◽  
Toll Lanes ◽  
Travel Time Savings ◽  
Mode Share ◽  
The Mean ◽  
Time Savings

Empirically derived value-of-time distributions are used to calculate the perceived benefits from the time saved by trucks in using toll lanes. The conditions on the SR-91 congestion pricing facility in California are used in a case study. Assuming that the value of time for trucks is lognormally distributed, the probabilistic truck mode share for the toll lanes was estimated separately for in-house and for-hire trucks. The mean values of time for toll-lane users and nonusers were estimated using Monte Carlo simulations. The benefits were calculated as the value of travel time savings that accrue for both toll-lane users and nonusers. The analyses found that the opening of the congestion pricing facility in 1995 has resulted in more than $2 million in annual savings for trucks. Trucks would realize an added $660,000 annually if the toll lanes were open to trucks. The disproportional share of the benefit goes to a few trucks with very high values of time, especially when the toll is expensive. Also, forhire trucks receive, on average, greater benefit than in-house carriers because of higher values of time.

scholarly journals Factor Analysis Techniques for the Assessment of Water Quality: A Case Study of Okun River, Ilorin, Kwara State

2019 ◽  
Vol 8 (1) ◽  
Author(s):  
H. K. Okoro ◽  
G. B. Adebayo ◽  
O.D Saliu ◽  
A. O. Adebayo
Keyword(s):  
Heavy Metals ◽  
Principal Component ◽  
Total Hardness ◽  
Temperature Conductivity ◽  
Mean Values ◽  
Copper Zinc ◽  
The Mean ◽  
Rapid Industrialization

Okun River caters for diverse needs. Resulting from rapid industrialization and urbanization, the quality of the river is significantly affected. The study of impact of discharged industrial wastewaters into Okun River was carried out. Physicochemical properties such as temperature, turbidity, conductivity, total suspended solids, total dissolved solids, colour, odour, pH, total hardness, chloride, and concentrations of heavy metals (chromium, manganese, iron, copper, zinc and cadmium) were assessed. The mean concentrations of heavy metals and the physicochemical parameters determined were compared with standards and tolerance limit. Cr was not detected in all the samples while Mn, Fe, Cu, Zn and Cd concentrations varied from 0.10-3.47 mg/L, 2.64-9.65 mg/L,0.37-3.79 mg/L, 0.22-1.53 mg/L and 0.00-0.03 mg/L respectively. The mean values of pH, temperature, conductivity, turbidity, TSS, TDS, total hardness and chloride ranged between 6.33-7.77, 25.0-29.0 oC, 325-815 mS/cm, 14.80-209.33 NTU, 733.33-1033.33 mg/L, 133-395.67 mg/L, 137.50-962.50 mg/L and 11.52- 49.04 mg/L respectively. The principal component analysis confirmed the heavy metals to be from anthropogenic and industrial origin.

scholarly journals An Italian Case Study for Assessing Nutrient Intake through Nutrition-Related Mobile Apps

Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 3073
Author(s):  
Lorenza Mistura ◽  
Francisco Javier Comendador Azcarraga ◽  
Laura D’Addezio ◽  
Deborah Martone ◽  
Aida Turrini
Keyword(s):  
Mobile Apps ◽  
Dietary Exposure ◽  
Dietary Survey ◽  
Mean Values ◽  
Italian Case ◽  
Nutrition Policies ◽  
The Mean ◽  
Google Play ◽  
Good Agreement

National food consumption surveys are crucial for monitoring the nutritional status of individuals, defining nutrition policies, estimating dietary exposure, and assessing the environmental impact of the diet. The methods for conducting them are time and resource-consuming, so they are usually carried out after extended periods of time, which does not allow for timely monitoring of any changes in the population’s dietary patterns. This study aims to compare the results of nutrition-related mobile apps that are most popular in Italy, with data obtained with the dietary software Foodsoft 1.0, which was recently used in the Italian national dietary survey IV SCAI. The apps considered in this study were selected according to criteria, such as popularity (downloads > 10,000); Italian language; input characteristics (daily dietary recording ability); output features (calculation of energy and macronutrients associated with consumption), etc. 415 apps in Google Play and 226 in the iTunes Store were examined, then the following five apps were selected: YAZIO, Lifesum, Oreegano, Macro and Fitatu. Twenty 24-hour recalls were extracted from the IV SCAI database and inputted into the apps. Energy and macronutrient intake data were compared with Foodsoft 1.0 output. Good agreement was found between the selected apps and Foodsoft 1.0 (high correlation index), and no significant differences were found in the mean values of energy and macronutrients, except for fat intakes. In conclusion, the selected apps could be a suitable tool for assessing dietary intake.

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