scholarly journals Radon survey in kindergartens and schools of Dushanbe, Republic of Tajikistan

2021 ◽  
Vol 14 (1) ◽  
pp. 124-132
Author(s):  
S. V. Muminov ◽  
B. B. Barotov ◽  
M. M. Makhmudova ◽  
F. A. Khamidov ◽  
M. Z. Akhmedov ◽  
...  
Keyword(s):  
Warm Season ◽  
Geological Structure ◽  
Mean Value ◽  
Heating Season ◽  
Annual Average ◽  
Average Value ◽  
Limit Value ◽  
Equivalent Concentration ◽  
Radon Survey ◽  
Equilibrium Equivalent Concentration

The paper presents results of the radon survey carried out in preschool and school institutions in Dushanbe, Republic of Tajikistan. Radon concentration was measured using solid state nuclear track detectors Radtrak2. Track detectors were exposed for 3 months during the heating and warm seasons of the year in the same premises. In total, the measurements were performed in 200 premises of 14 kindergartens and 36 schools. The radon equilibrium equivalent concentration during the heating and warm seasons and the annual average radon equilibrium equivalent concentration were calculated. Annual average radon equilibrium equivalent concentration in surveyed buildings ranged from 42 to 331 Bq/m3 with the mean value of 98 Bq/m3 on the first floor and 56 Bq/m3 on the second floor. It was shown that both seasonal values and annual average value of radon equilibrium equivalent concentration in the premises on the second floor are lower than in the premises on the first floor. The annual average effective dose to children from exposure to radon and its progeny in the premises of schools and kindergartens in Dushanbe ranged from 0,64 to 1,64 mSv. The limit value of annual average radon equilibrium equivalent concentration in dwellings and public buildings is set to 100 Bq/m3 for newly built buildings and 200 Bq/m3 for existing buildings in the Radiation safety norms (NRB-06) of the Republic of Tajikistan. This limit was exceeded only on the first floors in one kindergarten during the heating season, in three schools during the warm season and in eight schools during the heating season. When comparing the results of measurements of radon equilibrium equivalent concentration with data on the geological structure of underlying rocks at the locations of the surveyed buildings, no regularity was found. Additional detailed measurements in the buildings, including basements, will help to identify the source of radon entry into the indoor air and to develop recommendations for implementing radon remediation actions separately for each building. The survey results were also used to develop a radon map of Dushanbe.

scholarly journals Spatial Characteristics and Regional Transmission Analysis of PM2.5 Pollution in Northeast China, 2016–2020

2021 ◽  
Vol 18 (23) ◽  
pp. 12483
Author(s):  
Chunsheng Fang ◽  
Liyuan Wang ◽  
Zhuoqiong Li ◽  
Ju Wang
Keyword(s):  
Northeast China ◽  
Industrial Development ◽  
Mean Value ◽  
Liaoning Province ◽  
Hotspot Analysis ◽  
Annual Average ◽  
Air Mass ◽  
Average Value ◽  
Air Mass Trajectories ◽  
Pm2.5 Concentration

Northeast China is an essential industrial development base in China and the regional air quality is severely affected by PM2.5 pollution. In this paper, spatial autocorrelation, trajectory clustering, hotspot analysis, PSCF and CWT analysis are used to explore the spatial pollution characteristics of PM2.5 and determine the atmospheric regional transmission pattern for 40 cities in Northeast China from 2016 to 2020. Analysis of PM2.5 concentration characteristics in the northeast indicates that the annual average value and total exceedance days of PM2.5 concentration in Northeast China showed a U-shaped change, with the lowest annual average PM2.5 concentration (31 μg/m3) in 2018, decreasing by 12.1% year-on-year, and the hourly PM2.5 concentration exploding during the epidemic lockdown period in 2020. A stable PM2.5 pollution band emerges spatially from the southwest to Northeast China. Spatially, the PM2.5 in Northeast China has a high degree of autocorrelation and a south-hot–north-cool characteristic, with all hotspots concentrated in the most polluted Liaoning province, which exhibits the H–H cluster pattern and hotspot per year. Analysis of the air mass trajectories, potential source contributions and concentration weight trajectories in Northeast China indicates that more than 74% of the air mass trajectories were transmitted to each other between the three heavily polluted cities, with the highest mean value of PM2.5 pollution trajectories reaching 222.4 μg/m3, and the contribution of daily average PM2.5 concentrations exceeding 60 μg/m3 within Northeast China. Pollution of PM2.5 throughout the Northeast is mainly influenced by short-range intra-regional transport, with long-range transport between regions also being an essential factor; organized integration is the only fundamental solution to air pollution.

Variations of Climate, Surface Energy Budget, and Minimum Snow/Ice Extent over Canadian Arctic Landmass for 2000–16

2018 ◽  
Vol 31 (3) ◽  
pp. 1155-1172 ◽  
Author(s):  
Alexander P. Trishchenko ◽  
Shusen Wang
Keyword(s):  
Radiant Energy ◽  
Canadian Arctic ◽  
Warm Season ◽  
Correlation Coefficients ◽  
Energy System ◽  
Mean Value ◽  
Surface Energy Budget ◽  
Local Climate ◽  
Average Value ◽  
Snow And Ice

Abstract Snow and ice over land are important hydrological resources and sensitive indicators of climate change. The Moderate Resolution Imaging Spectroradiometer (MODIS) dataset at 250-m spatial resolution generated at the Canada Centre for Remote Sensing (CCRS) is used to derive the annual minimum snow and ice (MSI) extent over the Canadian Arctic landmass over a 17-yr time span (2000–16). The smallest MSI extent (1.53 × 105 km2) was observed in 2012, the largest (2.09 × 105 km2) was observed in 2013; the average value was 1.70 × 105 km2. Several reanalyses and observational datasets are assessed to explain the derived MSI variations: the ERA-Interim reanalysis, North American Regional Reanalysis (NARR), Clouds and the Earth’s Radiant Energy System (CERES) radiative fluxes, and European Space Agency’s GlobSnow dataset. Comparison with the Randolph Glacier Inventory (RGI) showed two important facts: 1) the semipermanent snowpack in the Canadian Arctic that persists through the entire melting season is a significant component relative to the ice caps and glacier-covered areas (up to 36% or 5.58 × 104 km2), and 2) the MSI variations are related to variations in the local climate dynamics such as warm season average temperature, energy fluxes, and snow cover. The correlation coefficients (absolute values) can be as high as 0.77. The reanalysis-based MSI estimates agree with satellite MSI results (average bias of 2.2 × 103 km2 or 1.3% of the mean value).

scholarly journals Thinner Sea Ice Contribution to the Remarkable Polynya Formation North of Greenland in August 2018

2021 ◽  
Author(s):  
Xiaoyi Shen ◽  
Chang-Qing Ke ◽  
Bin Cheng ◽  
Wentao Xia ◽  
Mengmeng Li ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Cover ◽  
Reanalysis Data ◽  
Mean Value ◽  
Ocean Model ◽  
North Coast ◽  
Average Value ◽  
The North ◽  
Wind Sea ◽  
The One

AbstractIn August 2018, a remarkable polynya was observed off the north coast of Greenland, a perennial ice zone where thick sea ice cover persists. In order to investigate the formation process of this polynya, satellite observations, a coupled ice-ocean model, ocean profiling data, and atmosphere reanalysis data were applied. We found that the thinnest sea ice cover in August since 1978 (mean value of 1.1 m, compared to the average value of 2.8 m during 1978–2017) and the modest southerly wind caused by a positive North Atlantic Oscillation (mean value of 0.82, compared to the climatological value of −0.02) were responsible for the formation and maintenance of this polynya. The opening mechanism of this polynya differs from the one formed in February 2018 in the same area caused by persistent anomalously high wind. Sea ice drift patterns have become more responsive to the atmospheric forcing due to thinning of sea ice cover in this region.

Resistance of a Ship Undergoing Oscillatory Motion

2010 ◽  
Vol 54 (02) ◽  
pp. 120-132
Author(s):  
Lawrence J. Doctors ◽  
Alexander H. Day ◽  
David Clelland
Keyword(s):  
Finite Depth ◽  
Mean Value ◽  
Wave Resistance ◽  
General Effect ◽  
Towing Tank ◽  
Ship Model ◽  
Average Value ◽  
Unsteady Effects ◽  
Oscillatory Cycle ◽  
Resistance Tests

In this paper, we describe extensions to the research of Doctors et al. (Doctors, L. J., Day, A. H., and Clelland, D., 2008, Unsteady effects during resistance tests on a ship model in a towing tank, Journal of Ship Research, 52, 4, 263–273) and Day et al. (Day, A. H., Clelland, D., and Doctors, L. J., 2009, Unsteady finite-depth effects during resistance tests in a towing tank, Journal of Marine Science and Technology, 14, 3, 387–397) in which the oscillations in the wave resistance during the constant-velocity phase of a towing-tank resistance test on a ship model were measured and predicted, in the cases of relatively deep and relatively shallow water. In the current study, the ship model was towed with a harmonic velocity component superimposed on the usual constant forward velocity. This work constitutes a first step in the understanding of the unsteady hydrodynamics of a racing shell (rowing boat). We show here that the unsteady wave resistance varies considerably from the traditional (steady) average value. Indeed, the wave resistance is frequently negative during part of the oscillatory cycle. However, the general effect is an increase in the temporal mean value of the wave resistance; this suggests that every effort should be made to reduce the unsteadiness of the motion. We also demonstrate that the unsteady wave-resistance theory provides an excellent prediction of the measured effects summarized here. These predictions are often within a few percent of the measured values of the resistance.

scholarly journals Mandibular Morphology Differences Between Edentulous And Dentate Assessed By Panoramic Radiographs

2017 ◽  
Vol 16 (2) ◽  
Author(s):  
Lidya Irani Nainggolan ◽  
Aude Layakni Girsang
Keyword(s):  
Panoramic Radiography ◽  
Mechanical Stimulus ◽  
Mean Value ◽  
Notch Depth ◽  
Cross Sectional ◽  
Gonial Angle ◽  
Average Value ◽  
Mandibular Morphology ◽  
Edentulous Patients ◽  
Ramus Height

Introduction: Facial profile can be influenced by edentulous condition that can change mandibular morphology that can affect mastication, digestion and psychosocial life. Edentulism causes absence of occlusal mechanical stimulus, decrease the activity of mastication muscles and increase mandibular bone resorption. These changes can be assessed using panoramic radiography by looking at the vertical dimension of the head of the condyle and its shape, ramus, and the angle of the mandible. The aim of the study was to assess the mean value and differences of mandibular morphology in edentulous and dentate patients using panoramic radiography. Materials and Methods: This was an analytical study with cross-sectional approach using purposive sampling methods. 50 dentate and edentulous patients who came to Dentistry Hospital of University of Sumatera Utara were used as sample. Data analysis was done using Independent T test and MannWhitney test. Results: Results showed that the average value of gonial angle, ramus height, condylar height, antegonial notch depth and ramus notch depth in edentulous patients were 125,38 ± 9,51; 35.98mm ± 4.26; 5.58mm ± 0.90; 2.11mm ± 1.04; and 2.73mm ± 0, 88, and the results showed that the average value of mandibular morphology in dentate patients were 123.34 ± 7.07; 38.15mm ± 3.23; 6.95mm ± 1.25; 1.41mm ± 0.77; and 2.15mm ± 0.59. Conclusion(s): There were significant differences in the values of ramus height, condylar height, antegonial notch depth, and ramus notch depth. Difference was also found in gonial angle value, but was not statistically significant.

scholarly journals Pengembangan LKPD Tema Tanah Airku Sub Tema Kota Palembang untuk Anak Kelompok B

2019 ◽  
Vol 1 (2) ◽  
pp. 129-141
Author(s):  
Gustiana Yuantini ◽  
Hasmalena Hasmalena ◽  
Syafdaningsih Syafdaningsih
Keyword(s):  
Small Group ◽  
Mean Value ◽  
Average Score ◽  
Self Evaluation ◽  
Average Value ◽  
Expert Review ◽  
Group Evaluation ◽  
Observation Methods ◽  
Evaluation Stage ◽  
Group B

This research aims to develop valid and practical student worksheet. Subjects in this research were B2 and B3 groups in state kindergarten of Pembina 2 Palembang. The model developed in this development was Rowntree consisting of One to one evaluation and small group evaluation. It was aimed to see the practicality and it used the Tessmer evaluation stage which consisted of self evaluation, expert review. Data collection techniques used in this research were interview, walkthrough and observation methods. According to the results of the research, it showed that the validity of the material and design obtained an average value of 3.77 in very valid categories. Student worksheet practicality test in terms of observations with a mean value of 95% in very practical category. The small group evaluation stage obtained an average score of 92% in the very practical category. Questionnaire result was 97% in valid category. From the result, it can be concluded that student worksheet theme of my homeland and sub-theme of Palembang city for group B children is valid and practical. It is also worth to use as learning student worksheet with Theme of my homeland

scholarly journals Pengaruh Model Pembelajaran Problem Based Learning pada Materi Hukum-Hukum Dasar Kimia terhadap Hasil Belajar Siswa Kelas X MAN 2 Model Palu

2018 ◽  
Vol 7 (3) ◽  
pp. 102
Author(s):  
Tri Sulistiyawati Lamalat ◽  
Supriadi Supriadi ◽  
Siti Nuryanti
Keyword(s):  
Statistical Analysis ◽  
Learning Outcomes ◽  
Problem Based Learning ◽  
Sampling Technique ◽  
Learning Model ◽  
Mean Value ◽  
Control Group ◽  
Control Group Design ◽  
Average Value ◽  
Quasi Experimental

Research on the effect of the problem-based learning model in the basic laws of chemistry on student’s learning outcomes in class X MAN 2 Model Palu has been done. This study aimed to determine the effect of the application of the problem-based learning model in the basic laws of chemistry on student’s learning outcomes in class X MAN 2 Model Palu. The type of research was a quasi-experimental study non-randomized design with pretest-posttest control group design. The sample was conducted with a purposive sampling technique. The study sample was students in class X MIA 6 as an experimental group (n = 22) and students in class X MIA 3 as a control group (n = 22). The data testing of students' learning outcomes used a non-parametric statistical analysis, the analysis of Mann-Whitney U-Test. The research results indicated that the mean value of the experiment class was high compared to the control class, 22.61 >18.39. The statistical analysis obtained that sig. 2-tailed (0,032) ˂ 0.05 and Zcalculation (-2.149) ˂ Ztable (-1.96). The average value of the experiment class was 82.95 while the average value of the control class was 73.64. So it can be concluded that there is the effect of applying the problem-based learning model in the basic laws of chemistry on student’s learning outcomes. 

scholarly journals Effects of the Dictogloss Method in Teaching Listening Skills to Students

2019 ◽  
Vol 8 (2) ◽  
pp. 69
Author(s):  
Muhaiminah Akib ◽  
Dian Saputra
Keyword(s):  
Mean Value ◽  
Control Group ◽  
Test Results ◽  
Listening Skills ◽  
Initial Test ◽  
Final Test ◽  
Learning Skills ◽  
Average Value ◽  
Quasi Experimental ◽  
Experimental Group

The purpose of this study was to investigate the effect of the dictogloss method in teaching listening to students' listening skills. This research was designed as a quasi-experimental. This study aims to investigate whether a material or treatment yields a different outcome for participants. There are two classes in this study, namely the experimental class (which is a sample to be treated with the dictogloss method) and the control class (using a method other than dictogloss). The results of this study are the results of data analysis showing that the results of learning skills in listening to the experimental group obtained the average value for the initial test of 60.33 and 71 for the final test score. While the control group using conventional methods has a mean value for the initial test of 60.1 and 70 for the final test. T test results also indicate that the significance value is 0,000. The significance value states smaller 0.05, it can be stated that Ha is accepted and Ho is rejected, which means that there is an influence of the dictogloss method in improving listening skills in students

International Collaborative Study for the Calibration of a Proposed Reference Preparation for Thromboplastin, Human Recombinant, Plain

1998 ◽  
Vol 79 (02) ◽  
pp. 439-443 ◽  
Author(s):  
Veena Chantarangkul ◽  
Barbara Negri ◽  
Marigrazia Clerici ◽  
Pier Mannuccio Mannucci ◽  
Armando Tripodi
Keyword(s):  
Collaborative Study ◽  
Mean Value ◽  
World Health ◽  
Practical Reasons ◽  
Calibration Model ◽  
Average Value ◽  
Reference Preparation ◽  
International Collaborative ◽  
Health Organization ◽  
International Collaborative Study

SummaryStocks of the International Reference Preparation (IRP) for thromboplastin, human, plain, coded BCT/253 and held by the World Health Organization (WHO) are nearly exhausted and must be replaced. For practical reasons the choice of the replacement candidate was restricted to two available human recombinant preparations which were coded as X/95 and Y/95 and calibrated in an international collaborative study involving 19 laboratories from Europe, Australia, Canada and Argentina. To minimize the differences between routes of calibration, the two candidates were calibrated against the existing WHO-IRP from human, rabbit and bovine origin and the final ISI was the resultant average value. On the basis of predefined criteria (i.e., within- and between-laboratory precision of the calibration and the conformity to the calibration model), X/95 was the preferred candidate. The assigned ISI (SE of the mean) value is 0.940 (0.0060) and the interlaboratory coefficient of variation 4.7%.

scholarly journals PENGEMBANGAN KUESIONER UNTUK MENGEVALUASI USABILITAS E-LEARNING

1970 ◽  
Vol 2 (1) ◽  
Author(s):  
Amalia Kiswandari ◽  
Rini Dharmastiti ◽  
Andi Rahadiyan Wijaya
Keyword(s):  
Interface Design ◽  
Effective Interaction ◽  
Main Tool ◽  
Mean Value ◽  
User Characteristics ◽  
Average Value ◽  
Existing Problems ◽  
Usability Problems ◽  
E Learning ◽  
Measuring Tool

Interface design of e-learning sometimes people see only as a choice, not the main point. But, the basic thing about interface is it the main tool that have function to give user direction about how is using e-learning because it covers all element in e-learning. Usability is the tool that can measure the effective interaction between user and interface to achieve specific purpose. Questionnaire is a tool that practical, efficient and the most using tool to evaluate the usability. But, there is not yet a specific questionnaire in Indonesia that can evaluate usability of e-learning in general.The purpose of this study is to develop a measuring tool which is questionnaire that can capture usability problems in e-learning, know the usability questions attributes that become themost influence on the evaluation of the usability case studies in e-learning, and evaluate the problem of usability in the case study with the questionnaires which have been developed. The object of this study is an e-learning developed by the University of Gadjah Mada, namely eLisa, Synthesis (Faculty of Economics and Business), Gamel (Faculty of Medicine), and Papyrus (Department of Electrical Engineering and Information Technology). A sample of 317 respondents.The results of this study are valid and reliable questionnaire, and obtained 14 usability dimensions with 56 variables question from factor analysis result. This questionnaire has the consistency and relevance with the problems that reflected in open-ended questions, covered views from the mean value of merit usability. The comparison of four e-learning is a consistent ratings between the average value of variable merit 56 questions on the contents of the variable 5 questions in the concluding section. The result of comparisons with other questionnaires showed that the questionnaire is more effective because it can cover 73.21% of the existing problems in a more specific eLisa and evaluate a problem of usability.This research can still be developed and refined from research object of e-learning are more general by a combination of respondents from several countries to prove the relationship of user characteristics in terms of preference, culture, and language affect the evaluation of each individual to the usabiltity of e-elarning.

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