scholarly journals Reducing Blasting-Induced Ground Vibrations at the Velkolom Čertovy Schody-Západ Quarry

2021 ◽  
Vol 906 (1) ◽  
pp. 012096
Author(s):  
Jakub Šrek ◽  
Milan Mikoláš
Keyword(s):  
Monitoring Network ◽  
Software Modeling ◽  
Ground Vibrations ◽  
Average Value ◽  
Measurement Site ◽  
Limit Value ◽  
Initiation System ◽  
Using Data ◽  
Vector Sum ◽  
Vibration Modeling

Abstract The study discusses the use of the electronic initiation system and software modeling to reduce ground vibrations induced by blasting works. The main part compares non-electric and electronic initiation systems, namely how the system-type affects the peak vector sum (PVS). The study evaluates blasting works conducted between 2011 and 2020 at the Velkolom Čertovy schody quarry. KonĘprusy limestone deposit mined from a quarry Velkolom Certovy schody belongs to one of the most significant mining locations in the Czech Republic. The main mining technology used in breaking rock mass at the Velkolom Čertovy schody quarry is blasting (namely bench blasts and overburden blasts). Blasting generates ground vibrations that affect the surroundings of the quarry. The information on ground vibrations is continuously collected at the predetermined measurement sites through a monitoring network. The network constantly monitors peak particle velocity (PPV), PVS, frequency, and other parameters. The key measurement site appears to be Prošek Dome (M15) in the Koneprusy Caves. At this measurement site, the limit value of the PVS is stipulated at 3.0 mm s-1. If this value is exceeded, it is necessary to establish measures which lead to blasting restrictions (e. g. decrease in the weight of the deck charge, bench blast rows reduction). To meet the criteria, the Velkolom Čertovy schody-západ quarry started to use the electronic initiation system (E*STAR) along with the specialized software Paradigm for vibration modeling. This study, using data collected at the measurement sites Prošek Dome (M15) and KonĘprusy No. 19, compares the PVS generated by the non-electric initiation system (Shock*Star) without modeling and by the electronic initiation system (E*STAR) with modeling. As reference years for non-electric initiation were stipulated years 2011, 2012, 2013, and for electronic initiation years 2018, 2019, and 2020. An analysis of 467 bench blasts executed at the quarry was conducted - or rather, the analysis of the PVS values collected at the pre-selected measurement sites. The analysis shows that the average value of the PVS at the measurement site Prošek Dome (M15) decreased from 2.05 mm s-1 to 1.64 mm s-1 when using the electronic initiation system with vibration modeling. The decrease in the PVS value was observed at the measurement site KonĘprusy No. 19 as well, namely from 0.48 mm s-1 to 0.31 mm s-1. In addition, significantly fewer occasions of exceeding the PVS limit value were reported at the measurement site Prošek Dome (M15), specifically from 6.7 % to 2.7 % of the blasting works conducted within the selected reference years. The study also describes fundamental principles of work with the Paradigm software. Based on the vibration analysis, parameters of the bench blasts need to be adjusted: timing, number of deck charges or rows, etc. Finally, the study summarizes the benefits of the electronic initiation system with modeling.

scholarly journals PENERAPAN MODEL PEMBELAJARAN KOOPERATIF JIGSAW UNTUK MENINGKATKAN MOTIVASI PADA SISWA KELAS V SEKOLAH DASAR

2020 ◽  
Vol 7 (2) ◽  
pp. 56-63
Author(s):  
Bandi Usman ◽  
Khairil Akbar ◽  
Kurnia Dyah Anggorowati
Keyword(s):  
Physical Education ◽  
Student Learning ◽  
Learning Model ◽  
Point Of View ◽  
Learning Motivation ◽  
Fifth Grade ◽  
Motivation To Learn ◽  
Average Value ◽  
Fifth Grade Students ◽  
Using Data

Abstrak: This study aims to increase student learning motivation in the field of physical education, sports and health. The learning model used is the application of the learning model through cooperative jigsaw to increase learning motivation in the field of physical education, sports and healthfor fifth grade students. Classroom action research (PTK) is carriedout using data collection techniques, namely motivation tests and questionnaires. The results of this study showed that in cycle 1, the average value of student learning motivation was 73% in the motivated category but not yet complete. Then in cycle II obtained a percentage of learning motivation of 90% categorized as motivated according to the success criteria and seen from the point of view of the maximum completeness criteria (KKM) students are said to be complete. The percentage of increasing learning motivation from cycle I to cycle II was 17%. The jigsaw cooperative learning model can increase student motivation, especially in sports and health physical education subjects.Keywords: learning Model, motivation to learn physical education sports and health.Abstrak: Penelitian ini bertujuan untuk meningkatkan motivasi belajar siswa pada bidang studi Pendidikan Jasmani Olahraga dan Kesehatan. Model pembelajaran yang digunakan adalah penerapan model pembelajaran melalui kooperatif Jigsaw untuk meningkatkan motivasi belajar pada bidang studi Pendidikan Jasmani Olahraga dan Kesehatan pada siswa kelas V, dilakukan penelitian tindakan kelas (PTK) dengan teknik pengumpulan data yakni tes dan angket motivasi. Hasil penelitian ini diperoleh siklus I nilai rata-rata motivasi belajar siswa presentase sebesar 73% kategori termotivasi tetapi belum tuntas. Kemudian pada siklus II diperoleh presentase motivasi belajar sebesar 90% dikategorikan termotivasi sesuai kriteria keberhasilan dan dilihat dari sudut pandang kriteria ketuntasan maksimal (KKM) siswa sudah dikatakan tuntas. Presentase peningkatan motivasi belajar siklus I ke siklus II yaitu 17%. Model pembelajaran kooperatif jigsaw dapat meningkatkan motivasi belajar siswa, terutama pada mata pelajaran Pendidikan Jasmani Olahraga dan Kesehatan.Kata Kunci: Model Pembelajaran, Motivasi Belajar Pendidikan Jasmani Olahraga dan Kesehatan

Spatial attenuation of intensities for central U.S. earthquakes

1976 ◽  
Vol 66 (3) ◽  
pp. 743-751
Author(s):  
Indra N. Gupta ◽  
Otto W. Nuttli
Keyword(s):  
United States ◽  
Ground Motion ◽  
Epicentral Distance ◽  
Near Field ◽  
Mississippi Valley ◽  
Average Value ◽  
Anelastic Attenuation ◽  
Central United States ◽  
Using Data ◽  
Spatial Attenuation

abstract Attenuation of ground motion in the central United States has to be determined principally using the Modified Mercalli (MM) intensity observations because of the absence of instrumental strong ground-motion data. Nuttli's previous studies of Mississippi Valley earthquakes indicate that higher-mode surface waves produce the largest ground motion except possibly in the near-field region. Particle velocity rather than acceleration correlates directly with intensity and the coefficient of anelastic attenuation has an average value of 0.10 per degree. Using data from isoseismals of the November 9, 1968, southern Illinois and the December 16, 1811, New Madrid, Missouri earthquakes and assuming a linear relationship between log(A/T) and MM intensity, attenuation is expressed by the equation, valid for I(R) ≧IV (MM), I ( R ) = I 0 + 3.7 − 0.0011 R − 2.7 log ⁡ R ; for R ≧ 20 k m where R is the epicentral distance in kilometers. This relationship shows fairly good agreement with isoseismals of many large earthquakes in the central United States and may therefore be useful in providing realistic estimates of spatial attenuation and hence of design earthquakes for a given site. It can also be sometimes useful in estimating the epicentral intensity of an earthquake whose maximum intensity is not reliably known.

scholarly journals Analysis of the distributions of hourly NO<sub>2</sub> concentrations contributing to annual average NO<sub>2</sub> concentrations across the European monitoring network between 2000 and 2014

2017 ◽  
Author(s):  
Christopher S. Malley ◽  
Erika von Schneidemesser ◽  
Sarah Moller ◽  
Christine F. Braban ◽  
W. Kevin Hicks ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Monitoring Network ◽  
Average Concentration ◽  
Monitoring Site ◽  
The European Union ◽  
Annual Average ◽  
Limit Value ◽  
Annual Average Concentration ◽  
Standard Set ◽  
Human Health Effects

Abstract. Exposure to nitrogen dioxide (NO2) is associated with negative human health effects, both for short-term peak concentrations and from long-term exposure to a wider range of NO2 concentrations. For the latter, the European Union has established an air quality limit value of 40 µg m−3 as an annual average. However, factors such as proximity and strength of local emissions, atmospheric chemistry and meteorological conditions means that there is substantial variation in the hourly NO2 concentrations contributing to an annual average concentration. The aim of this analysis was to quantify the nature of this variation at thousands of monitoring sites across Europe through the calculation of a standard set of chemical climatology statistics. Specifically, at each monitoring site that satisfied data capture criteria for inclusion in this analysis, annual NO2 concentrations, as well as the percentage contribution from each month, hour of the day, and hourly NO2 concentrations divided into 5 µg m−3 bins were calculated. Across Europe, 2010–2014 average annual NO2 concentrations (NO2AA) exceeded the annual NO2 limit value at 8 % of > 2500 monitoring sites. The application of this chemical climatology approach showed that sites with distinct monthly, hour of day, and hourly NO2 concentration bin contributions to NO2AA were not grouped in specific regions of Europe, and within relatively small geographic regions there were sites with similar NO2AA, but with differences in these contributions. Specifically, at sites with highest NO2AA, there were generally similar contributions from across the year, but there were also differences in the contribution of peak vs moderate hourly NO2 concentrations to NO2AA, and from different hours across the day. Trends between 2000 and 2014 for 259 sites indicate that, in general, the contribution to NO2AA from winter months has increased, as has the contribution from the rush-hour periods of the day, while the contribution from peak hourly NO2 concentrations has decreased. The variety of monthly, hour of day and hourly NO2 contribution bin contributions to NO2AA, across cities, countries and regions of Europe indicate that within relatively small geographic areas different interactions between emissions, atmospheric chemistry and meteorology produce variation in NO2AA and the conditions that produce it. Therefore, measures implemented to reduce NO2AA in one location may not be as effective in others. The development of strategies to reduce NO2AA for an area should consider i) the variation in monthly, hour of day and hourly NO2 concentration bin contributions to NO2AA within that area, and ii) how specific mitigation actions will affect variability in hourly NO2 concentrations.

Groundwater and soil CO2 efflux weekly monitoring network for the surveillance of Cumbre Vieja volcano, Canary Islands

2020 ◽  
Author(s):  
Cecilia Amonte ◽  
Alana Mulliss ◽  
Elizabeth Sampson ◽  
Alba Martín-Lorenzo ◽  
Claudia Rodríguez-Pérez ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Monitoring Program ◽  
Monitoring Network ◽  
Volcano Monitoring ◽  
Co2 Efflux ◽  
Chemical Parameters ◽  
High Concentration ◽  
Average Value ◽  
Physical Chemical ◽  
Cumbre Vieja

&lt;p&gt;La Palma Island (708.32 km&lt;sup&gt;2&lt;/sup&gt;) is located at the north-western end of the Canary Archipelago and is one of the youngest of the archipelago. In the last 123 ka, volcanic activity has taken place exclusively at Cumbre Vieja, the most active basaltic volcano in the Canaries, which is located at the southern part of the island. Since no visible geothermal manifestations occur at the surface environment of this volcano, during the last 20 years there has been considerable interest in the study of diffuse degassing as a powerful tool in the volcano monitoring program. In this study we have used two different geochemical approaches for volcano monitoring from October 2017 to November 2019. First, we have developed a network of 21 closed static chambers to determine soil CO&lt;sub&gt;2&lt;/sub&gt; effluxes. Additionally, we have monitored physical-chemical parameters (temperature, pH, electrical conductivity -EC-) and chemical/isotopic composition and dissolved gases in the water of two galleries (Pe&amp;#241;a Horeb and Trasvase Oeste) and one water well (Las Salinas). Soil CO&lt;sub&gt;2&lt;/sub&gt; effluxes for the alkaline traps showed an average value of 7.4 g&amp;#183;m&lt;sup&gt;-2&lt;/sup&gt;&amp;#183;d&lt;sup&gt;-1&lt;/sup&gt; for the entire Cumbre Vieja volcano. The gas sampled on the head space of the traps can be considered as CO&lt;sub&gt;2&lt;/sub&gt;-enriched air, showing an average value of 1,942 ppmV of CO&lt;sub&gt;2&lt;/sub&gt;. Regarding the CO&lt;sub&gt;2&lt;/sub&gt; isotopic composition (&amp;#948;&lt;sup&gt;13&lt;/sup&gt;C-CO&lt;sub&gt;2&lt;/sub&gt;), most of the stations exhibited CO&lt;sub&gt;2&lt;/sub&gt; composed by different mixing degrees between atmospheric and biogenic CO&lt;sub&gt;2&lt;/sub&gt; with slight contributions of deep-seated CO&lt;sub&gt;2&lt;/sub&gt;, with an average value of -19.3&amp;#8240;. The results of the physical-chemical parameters measured in waters showed mean temperature values of 23.7&amp;#186;C, 19.6&amp;#186;C and 22.1&amp;#186;C, 7.40, 6.27 and 6.60 for the pH and 1,710 &amp;#181;S&amp;#183;cm&lt;sup&gt;-1&lt;/sup&gt;, 411 &amp;#181;S&amp;#183;cm&lt;sup&gt;-1&lt;/sup&gt; and 41,100 &amp;#181;S&amp;#183;cm&lt;sup&gt;-1&lt;/sup&gt; for the EC, for Pe&amp;#241;a Horeb, Trasvase Oeste and Las Salinas, respectively. The &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C-CO&lt;sub&gt;2&lt;/sub&gt; composition of the dissolved gas has a mean value of -7.8&amp;#8240;, -10.2&amp;#8240; and -3.8&amp;#8240; vs. VPDB for Pe&amp;#241;a Horeb, Trasvase Oeste and Salinas, respectively. The highest values of CO&lt;sub&gt;2&lt;/sub&gt; efflux coincided with the stations showing highest CO&lt;sub&gt;2&lt;/sub&gt; concentration values located at the southern end of Cumbre Vieja, where the most recent volcanic eruption took place, and also on the northwest flank. This is in accordance with the results obtained for Las Salinas well, located in the south of the island, which show a high concentration of dissolved CO&lt;sub&gt;2&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C-CO&lt;sub&gt;2&lt;/sub&gt; values with a strong deep-seated CO&lt;sub&gt;2&lt;/sub&gt; contribution. This study represents an interesting contribution to detect early warning signals of future unrest episodes at Cumbre Vieja.&lt;/p&gt;

AVERAGE VALUE OF SUM OF EXPONENTS OF RUNS IN A STRING

2009 ◽  
Vol 20 (06) ◽  
pp. 1135-1146 ◽  
Author(s):  
KAZUHIKO KUSANO ◽  
WATARU MATSUBARA ◽  
AKIRA ISHINO ◽  
AYUMI SHINOHARA
Keyword(s):  
Upper Bound ◽  
Unit Length ◽  
Closed Formula ◽  
Alphabet Size ◽  
Average Value ◽  
Limit Value ◽  
Value Of It ◽  
Binary Strings

A substring w[i.j] in w is called a repetition of period p if w[k] = w[k + p] for any i ≤ k ≤ j - p. Especially, a maximal repetition, which cannot be extended neither to left nor to right, is called a run. The ratio of the length of the run to its period, i.e. [Formula: see text], is called an exponent. The sum of exponents of runs in a string is of interest. The maximal value of the sum is still unknown, and the current upper bound is 2.9n given by Crochemore and Ilie, where n is the length of a string. In this paper we show a closed formula which exactly expresses the average value of it for any n and any alphabet size, and the limit of this value per unit length as n approaches infinity. For binary strings, the limit value is approximately 1.13103. We also show the average number of squares in a string of length n and its limit value.

Prevalent Change in Overweight and Obesity in Children and Adolescents From 1995 to 2005 in Shandong, China

2010 ◽  
Vol 23 (6) ◽  
pp. 904-916 ◽  
Author(s):  
Yingxiu Zhang ◽  
Shurong Wang
Keyword(s):  
Public Health Problem ◽  
Skinfold Thickness ◽  
Overweight And Obesity ◽  
Shandong Province ◽  
Screening Criteria ◽  
Average Value ◽  
The Past ◽  
Periodic Monitoring ◽  
The Government ◽  
Using Data

Background: There is strong evidence of a positive secular trend in body mass index (BMI) and skinfold thickness (SFT) in most of the world over the past 10 years. However, no studies on this trend have been reported in Shandong Province, China. Aim: The present study assessed the decennial change in BMI and SFT in Shandong Province during the past 10 years and the prevalence of overweight and obesity among adolescents. Subjects and methods: The BMI and SFT of adolescents aged 7 to 18 years was calculated using data from 2 national surveys on students’ constitution and health carried out by the government in 1995 and 2005 in Shandong Province, China. The distribution of BMI and SFT was reported, and the prevalence of overweight and obesity were obtained according to the screening criteria of overweight and obesity for Chinese students using BMI. Results: In the past 10 years, the P50 (50th percentile) of BMI and SFT increased rapidly. The average increments of BMI and SFT were 0.91 kg/m2, 7.99 mm for boys and 0.55 kg/m2, 7.13 mm for girls, respectively. The prevalence of overweight and obesity increased rapidly: for overweight from 7.53% (boys), 4.89% (girls) in 1995 to 14.28% (boys), 8.75% (girls) in 2005; and for obesity from 2.92% (boys), 1.72% (girls) in 1995 to 10.78% (boys), 5.76% (girls) in 2005. Conclusion: The average value of BMI and SFT has increased over time; overweight and obesity among adolescents has become a serious public health problem. Comprehensive evidence-based strategies of intervention should be introduced, including periodic monitoring.

scholarly journals PERAN GUIDED INQUIRY DALAM PEMAHAMAN KONSEP SISWA KELAS VIII PADA PEMBELAJARAN TEOREMA PYTHAGORAS

2020 ◽  
Vol 3 (2) ◽  
pp. 111-122
Author(s):  
Hanifah Oktinasari ◽  
Rully Charitas Indra Prahmana
Keyword(s):  
Learning Outcomes ◽  
Inquiry Learning ◽  
Student Learning Outcomes ◽  
Pythagorean Theorem ◽  
Guided Inquiry ◽  
Average Value ◽  
Class Viii ◽  
Using Data ◽  
Mastery Criteria

This study aims to determine the role of Guided Inquiry in understanding students' concepts in learning the Pythagorean theorem, through student worksheet-based guided inquiry learning models. This study uses descriptive qualitative research methods, which were carried out in class VIII D at SMP Muhammadiyah 1 Gamping. Data collection techniques used were documentation, observation, and written tests. Data obtained in this study were analyzed using data triangulation techniques. The results showed that the Guided Inquiry had a role in helping students to understand the concept of the Pythagorean theorem formula, through several stages of learning. In learning that uses guided inquiry, students can understand the Pythagorean theorem formula by finding it on their own and being facilitated by the teacher. Also, student learning outcomes indicate that the average value obtained by students is above the Minimum Mastery Criteria score for mathematics subjects of 65.

RESPONSE OF THE CZECH RMN NETWORK TO THUNDERSTORM ACTIVITY

2019 ◽  
Vol 186 (2-3) ◽  
pp. 215-218
Author(s):  
J Šlegl ◽  
J Minářová ◽  
P Kuča ◽  
I Kolmašová ◽  
O Santolík ◽  
...  
Keyword(s):  
Czech Republic ◽  
Monitoring Network ◽  
Thunderstorm Activity ◽  
Radiation Monitoring ◽  
Radon Progeny ◽  
Radiation Background ◽  
The Czech Republic ◽  
Charge Structure ◽  
Gamma Background ◽  
Using Data

ABSTRACT Thunderstorm ground enhancement (TGE) is a phenomenon that enhances radiation background on the ground related to thunderstorm activity and charge structure of the thundercloud. On the other hand, the rise of gamma background is connected with precipitation by the washout of radon progeny from the atmosphere. In our analysis, we examined known enhancements of gamma background, previously attributed solely to radon progeny, using data from the Czech Radiation Monitoring Network (RMN) to investigate the enhancements with respect to thunderstorms and TGE phenomena. We also used radar precipitation data and data from the lightning location network to analyze their influences on the radiation background enhancement during three thunderstorm events that occurred in summer 2016 over the Czech Republic (Central Europe). We state that the RMN might have detected TGE over the Czech Republic.

Electric Conductivity and Power of Hydrogen Value of Processed Seawater Using a Distillation Tool

2021 ◽  
Vol 9 (1) ◽  
pp. 49-59
Author(s):  
Muliyadi Muliyadi ◽  
Idayani Sangadjisowohy
Keyword(s):  
Electrical Conductivity ◽  
Ph Value ◽  
Liquid Waste ◽  
Residential Areas ◽  
Average Value ◽  
Data Processing Software ◽  
Before And After ◽  
Post Test ◽  
Using Data ◽  
Distillation Equipment

Water pollution in the coastal areas of Ternate has shown a serious increase. It can be seen from the amount of garbage and the appearance of water turbidity in areas near residential areas. Based on a preliminary study, several residents behind the mountain also complained about the brackishness of their wells due to seawater intrusion. This study aims to determine the effectiveness of the distillation method on decreasing the value of electrical conductivity and power of hydrogen (pH) in seawater. This research is an experimental study with a post-test only group control design with a sample of 10 litres of liquid waste from three places, namely Muara Maliaro, Muara Pasar Sayur, Muara Pelabuhan Besar. The results of this study were processed using data processing software with paired T-test and Wilcoxon. The average value of DHL in samples 1, 2, 3 after distillation was carried out successively was 116 mhos/cm, 109.33 mhos/cm, 109.66 mhos/cm. The average pH value in samples 1, 2, 3 after distillation in all samples have shown normal values ​​with an average of  7. There is a difference in the DHL value before and after distillation with the Sig value (2-tailed), which is <0.05. There is a different pH value before and after distillation with the Sig value (2-tailed) <0.05. Distillation equipment can reduce the value of electrical conductivity and pH in seawater.

Assessment for Urban Environmental Status Based on Nuclear Approximation

2017 ◽  
Vol 6 (4) ◽  
pp. 13-20
Author(s):  
Екатерина Бельская ◽  
Ekaterina Belskaya ◽  
А. Медведев ◽  
A. Medvedev ◽  
Е. Михов ◽  
...  
Keyword(s):  
Ecological Status ◽  
Monitoring Network ◽  
Space Distribution ◽  
Nonparametric Model ◽  
State Monitoring ◽  
Atmospheric Air ◽  
Correct Definition ◽  
Ecological Problems ◽  
Using Data ◽  
Definition Of

In the work has been demonstrated the importance of the process of revealing and forecasting for existing ecological problems related to urban environment (on the example of Krasnoyarsk city). Have been considered the main sources of atmospheric air pollution. Has been argued the need for building the model for urban environment’s ecological state assessment in the context of new type of models (named H-models). In the construction of mathematical models for ecological problems solution the correct definition of variables essentially acting on considered environment’s ecological status is playing an important part. A novel way for determining of the most informative variables has been proposed. Based on presented by the authors approach to the modeling has been developed a nonparametric model for formaldehyde space distribution along city’s territory using data of atmospheric air state monitoring network. Modeling velocity allows use this method in the real-time.

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