scholarly journals Quality assessment of Dobson spectrophotometers for ozone column measurements before and after automation at Arosa and Davos

2021 ◽  
Vol 14 (6) ◽  
pp. 4203-4217
Author(s):  
René Stübi ◽  
Herbert Schill ◽  
Eliane Maillard Barras ◽  
Jörg Klausen ◽  
Alexander Haefele
Keyword(s):  
Standard Deviation ◽  
Developed Countries ◽  
Global Network ◽  
Manual Operation ◽  
Operation Procedure ◽  
Before And After ◽  
Mean Differences ◽  
Automated Data Acquisition ◽  
And Control ◽  
Ozone Column

Abstract. The longest ozone column measurement series are based on the Dobson sun spectrophotometers developed in the 1920s by Gordon B. W. Dobson. These instruments still constitute an important part of the World Meteorological Organization's global network due to their optical qualities and ruggedness. The primary drawback of this instrument is the effort needed for its manual operation. In industrialized and some less developed countries, most stations have made the choice to replace the Dobson by the automated Brewer sun spectrophotometers, but some are still relying on the Dobson instrument. One of them is the Arosa station where both instrument types are run in parallel. Here, an automated version of the Dobson instrument was developed and implemented recently. In the present paper, the results of the analysis of simultaneous measurements from pairs of Dobson instruments that were either collocated at Arosa or Davos or operated one at each location are presented for four distinct time periods: 1992–2012 – manual vs. manual operation of collocated Dobson instruments (MMC); 2012–2013 – manual vs. automated operation of collocated Dobson instruments (MAC); 2012–2019 – automated vs. automated operation of collocated Dobson instruments (AAC); 2016–2019 – automated vs. automated operation of distant Dobson instruments (AAD). The direct comparison of two instruments using the standard operation procedure during the MMC period gives a metric necessary to validate the automated version of Dobson instruments. The direct comparison of two collocated instruments using the standard manual operation procedure reveals random differences of coincident observations with a standard deviation of ∼ 0.45 % and monthly mean differences between −1.0 % and +0.8 %. In most cases the observed biases are not statistically significant. The same analysis of two automated Dobson instruments yields significantly smaller standard deviation of ∼ 0.25 % and biases of between −0.7 % and 0.8 %. This demonstrates that the repeatability has improved with the automation, while the systematic differences are only marginally smaller. The analysis of the AAD period of coincident measurements from the distant sites Arosa and Davos reveals a small positive bias (not significant) compatible with the 250 m altitude difference. The description of the automated data acquisition and control of the Dobson instrument is presented in a separate paper (Stübi et al., 2020).

scholarly journals Quality assessment of Dobson spectrophotometers for ozone column measurements before and after automation at Arosa and Davos

2020 ◽  
Author(s):  
René Stübi ◽  
Herbert Schill ◽  
Eliane Maillard Barras ◽  
Jörg Klausen ◽  
Alexander Haefele
Keyword(s):  
Standard Deviation ◽  
Developed Countries ◽  
Global Network ◽  
Manual Operation ◽  
Operation Procedure ◽  
Before And After ◽  
Mean Differences ◽  
Automated Data Acquisition ◽  
And Control ◽  
Ozone Column

Abstract. The longest ozone column measurements series are based on the Dobson sun spectrophotometers developed in the 1920s by Prof. G. B. W. Dobson. These instruments still constitute an important part of the World Meteorological Organization's global network due to their optical qualities and ruggedness. The primary drawback of this instrument is the effort needed for its manual operation. In industrialized and some lesser developed countries, most stations have made the choice to replace the Dobson by the automated Brewer sun spectrophotometers but some are still relying on the Dobson instrument. One of them is the Arosa station where both instrument types are run in parallel. Here, an automated version of the Dobson instrument was developed and implemented recently. In the present paper, the results of the analysis of simultaneous measurements from pairs of Dobson instruments that were either collocated at Arosa or Davos, or operated one at each location, are presented for four distinct time periods: – 1992–2012 : Manual vs. Manual operation of Collocated Dobson instruments (MMC) – 2012–2013 : Manual vs. Automated operation of Collocated Dobson instruments (MAC) – 2012–2019 : Automated vs. Automated operation of Collocated Dobson instruments (AAC) and – 2016–2019 : Automated vs. Automated operation of Distant Dobson instruments (AAD) The direct comparison of two instruments using the standard operation procedure during the MMC period gives a metric necessary to validate the automated version of Dobson instruments. The direct comparison of two collocated instruments using the standard manual operation procedure reveals random differences of coincident observations with a standard deviation of ∼0.45 % and monthly mean differences between −1.0 and +0.8 %. In most cases the observed biases are not statistically significant. The same analysis of two automated Dobson instruments yields significantly smaller standard deviation of ∼0.25 % and biases of between −0.7 % and 0.8 %. This demonstrates that the repeatability has improved with the automation while the systematic differences are only marginally smaller. The description of the automated data acquisition and control of the Dobson instrument is presented in a separate paper (Stübi et al. , 2020).

scholarly journals A fully Automated Dobson Sun Spectrophotometer for total column ozone and Umkehr measurements

2020 ◽  
Author(s):  
René Stübi ◽  
Herbert Schill ◽  
Jörg Klausen ◽  
Eliane Maillard Barras ◽  
Alexander Haefele
Keyword(s):  
Global Network ◽  
Automated Control ◽  
Total Column Ozone ◽  
Manual Operation ◽  
Clear Sky ◽  
Technical Details ◽  
Column Ozone ◽  
Sky Conditions ◽  
Ozone Column ◽  
Dobson Spectrophotometer

Abstract. The longest ozone column measurements series are based on the Dobson sun spectrophotometers developed in the 1920s by Prof. G. B. W. Dobson. These ingenious and robustly designed instruments still constitute an important part of the global network presently. However, the Dobson sun spectrophotometer needs manual operation which leads to the discontinuation of its use at many stations. To overcome this problem, MeteoSwiss developed a fully automated version of the Dobson spectrophotometer. The description of the data acquisition and automated control of the instrument is presented here with some technical details. The results of different tests performed regularly to control the instrument good working operation are illustrated and discussed. Compared to manual operation, the automation results in higher frequency measurements with lower random error and additional housekeeping information to characterise the measuring conditions. The automated Dobson instrument allows a continuous observation of the ozone column with a resolution of ~1 DU unit under clear sky conditions.

scholarly journals Effect of an Educational-Psychological Intervention on Anxiety, Bodily Embarrassment, Judgment Concern, and Comfort in Female Patients who referred to a Male General Surgeon for Colorectal Examination

2019 ◽  
Vol 5 (1) ◽  
Keyword(s):  
Psychological Intervention ◽  
Intervention Group ◽  
General Surgeon ◽  
Chi Square ◽  
Female Patients ◽  
Significant Difference ◽  
Before And After ◽  
Mean Differences ◽  
And Control ◽  
Educational Psychological

Introduction: Psychological issues are big barriers for female patients referring for colorectal examination. Some interventions might reduce these issues. This study aimed to determine the effect of an educational-pyschyological intervention on anxiety, bodily embarrassment, judgment concern, and comfort in female patients who referred to a male general surgeon for colorectal examination. Methods: This clinical trial with a pre/posttest design was conducted in Imam Hassan Mojtaba Clinic, Darab, Iran. Total of 110 female patients who referred to a male general surgeon for colorectal examination were included in this study. The participants were randomly assigned to an intervention (n=55) and control (n=55) groups. The psychological training program was conducted for 60 minutes (30 minutes for examinations and 30 minutes for the psychological counseling). Beck Anxiety Inventory and Medical Embarrassment Questionnaires were used. The data were analyzed using chi-square, independent and paired t-test. Results: After the intervention, a significant difference was observed between the intervention and control groups in terms of bodily embarrassment and comfort. In addition, a significant difference was found in the intervention group regarding the mean differences of anexity, bodily embarrassment, judgment concern, and comfort scores before and after the intervention (p<0.001). Conclusion: The findings showed that the educational-psychological intervention reduced anxiety, bodily embarrassment, and judgment concern, and it improved comfort in female patients who referred to the male general surgeon for colorectal examination. Hence, this intervention might be used in primary, secondary and tertiary health centers to educate patients when referring to a male surgeon.

scholarly journals A fully automated Dobson sun spectrophotometer for total column ozone and Umkehr measurements

2021 ◽  
Vol 14 (8) ◽  
pp. 5757-5769
Author(s):  
René Stübi ◽  
Herbert Schill ◽  
Jörg Klausen ◽  
Eliane Maillard Barras ◽  
Alexander Haefele
Keyword(s):  
Global Network ◽  
Automated Control ◽  
Total Column Ozone ◽  
Manual Operation ◽  
Clear Sky ◽  
Technical Details ◽  
Column Ozone ◽  
Sky Conditions ◽  
Ozone Column

Abstract. The longest ozone column measurement series are based on the Dobson sun spectrophotometers developed in the 1920s by Prof. G. B. W. Dobson​​​​​​​. These ingenious and robustly designed instruments still constitute an important part of the global network presently. However, the Dobson sun spectrophotometer requires manual operation, which has led to the discontinuation of its use at many stations, thus disrupting long-term records of observation. To overcome this problem, MeteoSwiss developed a fully automated version of the Dobson spectrophotometer. The description of the data acquisition and automated control of the instrument is presented here with some technical details. The results of different tests performed regularly to assess the instrument's good working conditions are illustrated and discussed. Compared to manual operation, automation results in a higher number of daily measurements with lower random error and additional housekeeping information to characterize the measuring conditions. The automated Dobson instrument allows for continuous observation of the ozone column with a resolution of ∼ 1 DU under clear-sky conditions.

EFEKTIVITAS METODE DEMONSTRASI DALAM MENINGKATKAN HASIL BELAJAR SISWA SEKOLAH MENENGAH KEJURUAN PADA PENGAJARAN SISTEM KOLOID

2013 ◽  
Vol 19 (1) ◽  
pp. 28
Author(s):  
Hamda Situmorang ◽  
Manihar Situmorang
Keyword(s):  
High School ◽  
High School Students ◽  
Abstract Concept ◽  
Vocational High School ◽  
School Students ◽  
Lecture Method ◽  
Colloid System ◽  
Before And After ◽  
The Right ◽  
And Control

Abstract Implementation of demonstration method in the teaching of chemistry is assigned as the right strategy to improve students’ achievement as it is proved that the method can bring an abstract concept to reality in the class. The study is conducted to vocational high school students in SMKN1 Pargetteng getteng Sengkut Pakfak Barat at accademic year 2013. The teaching has been carried out three cycles on the teaching of chemistry topic of colloid system. In the study, the class is divided into two class, experiment class and control class. The demontration method is used to teach students in experimental class while the teaching in control class is conducted with lecture method. Both are evaluated by using multiple choise tests before and after the teaching procedures, and the ability of students to answer the problems are assigned as students’ achievements. The results showed that demonstration method improved students’ achievement in chemistry. The students in experimental class who are taughed with demonstration method (M=19.08±0.74) have higher achievements compare with control class (M=12.91±2.52), and both are significantly different (tcalculation 22.85 > ttable 1.66). The effectivity of demostration method in experimental class (97%) is found higer compare to conventional method in control class (91%).

Effects of Time and Perceptual Orientation on Actors' and Observers' Attributions

1984 ◽  
Vol 58 (1) ◽  
pp. 23-30
Author(s):  
Donald S. Martin ◽  
Ming-Shiunn Huang
Keyword(s):  
Video Recording ◽  
Control Group ◽  
Control Groups ◽  
Video Recordings ◽  
Before And After ◽  
Perceptual Orientation ◽  
Initial Difference ◽  
Variety Show ◽  
And Control ◽  
Unrelated Variety

The actor/observer effect was examined by Storms in a 1973 study which manipulated perceptual orientation using video recordings. Storms' study was complex and some of his results equivocal. The present study attempted to recreate the perceptual reorientation effect using a simplified experimental design and an initial difference between actors and observers which was the reverse of the original effect. Female undergraduates performed a motor co-ordination task as actors while watched by observers. Each person made attributions for the actor's behaviour before and after watching a video recording of the performance. For a control group the video recording was of an unrelated variety show excerpt. Actors' initial attributions were less situational than observers'. Both actors and observers became more situational after the video replay but this effect occurred in both experimental and control groups. It was suggested the passage of time between first and second recording of attributions could account for the findings and care should be taken when interpreting Storms' (1973) study and others which did not adequately control for temporal effects.

Stick Figure and Think, Talk And Write: Integrating Media With Teaching Strategy For A Better Writing Competence

2017 ◽  
Vol 2 (1) ◽  
pp. 46
Author(s):  
Eva Sudarwati ◽  
Shynta Amalia
Keyword(s):  
Teaching Strategy ◽  
T Test ◽  
Narrative Writing ◽  
Control Groups ◽  
Stick Figure ◽  
Significant Difference ◽  
Quasi Experimental ◽  
Mean Differences ◽  
And Control ◽  
Writing Competence

Abstract This study attempts to see the effect of Think, Talk, and Write strategy on the students’ narrative writing competence. Considering the importance of the use of teaching media, this study tries to integrate Stick Figure as a teaching media in Think, Talk, and Write Strategy. A quasi experimental study was conducted to see the improvement of the students’ narrative writing competence. It involved 42 students who were selected on the basis of convenience sampling and assigned into two groups; experimental and control groups. The statistical analyses of paired sample t-test in experimental group showed that there was significant improvement on the students’ writing competence before (M=5.77, SD= 2.342) and after (M= 11.79, SD= 2.342), t(21)=12.059, p<0.05.Moreover, the result of independent t-test between experimental and control groups showed a significant difference. It can be seen that the mean differences was 3.79545 and the significance value is lower than 0.05, 0.000<0.05.

The Effect of Using Flipped Classroom Model to Improve Iraqi EFL Learners’ Pronunciation in English at University Level

2020 ◽  
Vol 1 (40) ◽  
pp. 631-654
Author(s):  
Khaldoon Waleed Husam Al-Mofti
Keyword(s):  
Language Learning ◽  
Flipped Classroom ◽  
Efl Learners ◽  
English Pronunciation ◽  
Before And After ◽  
Quasi Experimental ◽  
University Level ◽  
The University ◽  
And Control ◽  
Experimental Group

For Iraqi EFL learners who are studying English pronunciation in a traditional instruction method often requires more effort and hard work. Thus, using new methods of teaching such as the flipped classroom model (FCM) is necessary to facilitate learning and improve performance. Hence, this study reports on explanatory research that investigates the effect of using the FCM in the teaching of English pronunciation for Iraqi EFL learners at the university level. The study implemented mixed research methods for data collection in a quasi-experimental analysis. Therefore, two tests were conducted on the assigned groups to measure the effect of the FCM before and after the intervention. Besides, a questionnaire and interviews were used on the experiment group students to collect data about their perceptions of the FCM. The study length (lasted)  was 15 weeks and is comprised of 60 students from the department of English, College of Arts at the University of Anbar. The students were divided into two groups, experimental, and control with 30 students in each group. The findings revealed that there was a significant statistical difference between the two groups in favour of the experimental group with better performance, indicating that the FCM has considerably assisted the Iraqi EFL learners to improve their English pronunciation. Moreover, the students expressed their positive feedback and satisfaction on the use of the FCM in their responses to the questionnaire and the interviews. As such, the current study recommends further research to study the effect of applying the FCM in areas and disciplines other than language learning.

Using advanced control, post-denitrification and equalisation to improve the performance of a submerged filter

2000 ◽  
Vol 41 (4-5) ◽  
pp. 177-184 ◽  
Author(s):  
K.H. Sørensen ◽  
D. Thornberg ◽  
K.F. Janning
Keyword(s):  
Energy Consumption ◽  
Total N ◽  
Control Loops ◽  
Effluent Quality ◽  
Advanced Control ◽  
Before And After ◽  
And Control ◽  
Side Flow ◽  
Configuration Control ◽  
Control Post

In 1998, the capacity of the BIOSTYR® submerged biofilter at Nyborg WWTP was extended from 48,000 PE to 60,000 PE including advanced sensor based control, post-denitrification in BIOSTYR® and equalization of side flows. The existing configuration with 8 BIOSTYR® DN/N cells is based on pre-denitrification and an internal recirculation of 600–800%. The extended plant comprises 7 BIOSTYR® DN/N cells with 50–225% recirculation followed by 3 BIOSTYR DN cells for post-denitrification. The advanced control loops include blower control, control of the number of active cells (stand-by), automatic switch to high load configuration, control of the side flow equalization, control of the internal recirculation and control of the external carbon source dosing. In this paper, the achieved improvements are documented by comparing influent and effluent data, methanol and energy consumption from comparable periods before and after the extension. Although the nitrogen load to the plant was increased by 20% after the extension, the effluent quality has improved significantly with a reduction of Total-N from 7–8 mg/l to 3–4 mg/l. Simultaneously, the methanol consumption has been reduced by more than 50% per kg removed nitrogen. The energy consumption remained constant although the nitrogen load was increased by 20% and the inflow by 80%.

Melatonin Improves Erythropoietin Hyporesponsiveness via Suppression of Inflammation

2019 ◽  
Vol 14 (3) ◽  
pp. 203-208
Author(s):  
Evan Noori Hameed ◽  
Haydar F. Hadi AL Tukmagi ◽  
Hayder Ch Assad Allami
Keyword(s):  
Iron Status ◽  
Transferrin Saturation ◽  
Control Group ◽  
Base Line ◽  
Inadequate Response ◽  
Inflammatory Parameters ◽  
Tnf Α ◽  
Before And After ◽  
And Control ◽  
Controlled Clinical Study

Background: Inadequate response to Erythropoietin Stimulating Agents (ESA) despite using relatively larger doses regimen represents a potential risk factor of Cardiovascular (CV) related mortality in addition to health-care economic problems in anemic patients with Chronic Kidney Disease (CKD). Erythropoietin (EPO) hyporesponsiveness related to inflammation has been increased progressively. Melatonin is well known as a potent anti-inflammatory agent. Therefore, the current study was designed to evaluate whether melatonin could improve anemic patients response to EPO. Methods: This single controlled clinical study was carried out in 41 CKD patients with hemoglobin (Hb) levels less than 11g/dl divided randomly in a 1:1 ratio into 2 groups; treatment group who received 5mg melatonin plus their regular treatments and control group who received their regular treatments only. Hematological and iron status parameters include Hb level, serum iron (S. iron), Transferrin Saturation Ratio (TSAT) and serum ferritin (S. ferritin) in addition to inflammatory parameters that include tissue necrotic factor alfa (TNF-α), interleukin-1beta (IL-1β) and interleukin-6 (IL-6) determined before and after 12 weeks of treatment. Results: Melatonin remarkably increases the Hb level with a significant increase in S. iron and TSAT compared to baseline. The elevation of S. iron and TSAT was significantly higher in the melatonin group. Additionally, all inflammatory markers estimated were reduced significantly by melatonin compared to base line and control group. Conclusion: The results of the current study showed that melatonin has an advantageous effect on improving EPO response in anemic patients with CKD.

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