model measurement
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2021 ◽  
Vol 2 (2) ◽  
pp. 44-50
Author(s):  
Shuhada Abdul Raof ◽  
Aede Hatib Musta’amal ◽  
Farid Kamil Zamzuri ◽  
Mohammad Hafiz Salleh

This pilot study aims to produce empirical evidence regarding the validity and reliability of instrument of the perception of vocational college diploma students towards the Outcome Based Education (OBE) approach. Validity and reliability were analysed using Rasch Model Measurement assisted by Winsteps 3.72 software. This research instrument contained 26 items and was distributed to 60 diploma students of vocational college at the Northern Zone. Validity analysis of the instrument was done through four functional testings. For reliability and separation of respondents, it was found that the individual reliability value was 0.91, while that for items demonstrated an item value of 0.94 and item separation index of 3.90. Results from the analysis of polarity item found that 25 items had a positive PMC value between 0.52-0.83. Meanwhile, analysis on item fit found 23 items with an outfit mean-square value between 0.41 and 1.24. This situation suggested three items that require attention. In the analysis on local dependence that determines dependent items based on the standardised residual correlation value, it was shown that the correlation value for the items used did not overlap with that of other items. These findings provided the evidence that the instrument of perception of vocational college diploma students on OBE approach has a high level of validity and reliability to be used in actual studies.                                                                                                                 


2021 ◽  
Vol 3 (4) ◽  
pp. 85-105
Author(s):  
Siti Kustinah ◽  
Muhammad Anggionaldi

The use of school aid funds (BOS) must be accounted for by the beneficiary schools. The performance of a school can be judged by how good the accountability of the school is. The principal plays an important role in realizing accountability in the school he leads. The principal's leadership and motivation are factors that can encourage the achievement of good school accountability. This study aims to determine the effect of leadership and motivation in measuring accountability using the CPA (Calibrating Public Accountability Model) measurement model. The research method used is quantitative verification. The population in this study were all school principals in West Bandung Regency and Cimahi City with the sample technique using a simple random technique. Data collection techniques using questionnaires. Data analysis technique using PLS. The results showed that there was an effect of leadership on accountability, while motivation had no effect on accountability. Simultaneously leadership and motivation affect accountability.


2021 ◽  
Vol 14 (11) ◽  
pp. 7021-7046
Author(s):  
Yao Ge ◽  
Mathew R. Heal ◽  
David S. Stevenson ◽  
Peter Wind ◽  
Massimo Vieno

Abstract. Atmospheric pollution has many profound effects on human health, ecosystems, and the climate. Of concern are high concentrations and deposition of reactive nitrogen (Nr) species, especially of reduced N (gaseous NH3, particulate NH4+). Atmospheric chemistry and transport models (ACTMs) are crucial to understanding sources and impacts of Nr chemistry and its potential mitigation. Here we undertake the first evaluation of the global version of the EMEP MSC-W ACTM driven by WRF meteorology (1∘×1∘ resolution), with a focus on surface concentrations and wet deposition of N and S species relevant to investigation of atmospheric Nr and secondary inorganic aerosol (SIA). The model–measurement comparison is conducted both spatially and temporally, covering 10 monitoring networks worldwide. Model simulations for 2010 compared use of both HTAP and ECLIPSEE (ECLIPSE annual total with EDGAR monthly profile) emissions inventories; those for 2015 used ECLIPSEE only. Simulations of primary pollutants are somewhat sensitive to the choice of inventory in places where regional differences in primary emissions between the two inventories are apparent (e.g. China) but are much less sensitive for secondary components. For example, the difference in modelled global annual mean surface NH3 concentration using the two 2010 inventories is 18 % (HTAP: 0.26 µg m−3; ECLIPSEE: 0.31 µg m−3) but is only 3.5 % for NH4+ (HTAP: 0.316 µg m−3; ECLIPSEE: 0.305 µg m−3). Comparisons of 2010 and 2015 surface concentrations between the model and measurements demonstrate that the model captures the overall spatial and seasonal variations well for the major inorganic pollutants NH3, NO2, SO2, HNO3, NH4+, NO3-, and SO42- and their wet deposition in East Asia, Southeast Asia, Europe, and North America. The model shows better correlations with annual average measurements for networks in Southeast Asia (mean R for seven species: R7‾=0.73), Europe (R7‾=0.67), and North America (R7‾=0.63) than in East Asia (R5‾=0.35) (data for 2015), which suggests potential issues with the measurements in the latter network. Temporally, both model and measurements agree on higher NH3 concentrations in spring and summer and lower concentrations in winter. The model slightly underestimates annual total precipitation measurements (by 13 %–45 %) but agrees well with the spatial variations in precipitation in all four world regions (0.65–0.94 R range). High correlations between measured and modelled NH4+ precipitation concentrations are also observed in all regions except East Asia. For annual total wet deposition of reduced N, the greatest consistency is in North America (0.75–0.82 R range), followed by Southeast Asia (R=0.68) and Europe (R=0.61). Model–measurement bias varies between species in different networks; for example, bias for NH4+ and NO3- is largest in Europe and North America and smallest in East Asia and Southeast Asia. The greater uniformity in spatial correlations than in biases suggests that the major driver of model–measurement discrepancies (aside from differing spatial representativeness and uncertainties and biases in measurements) are shortcomings in absolute emissions rather than in modelling the atmospheric processes. The comprehensive evaluations presented in this study support the application of this model framework for global analysis of current and potential future budgets and deposition of Nr and SIA.


Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1381
Author(s):  
Amy Foulds ◽  
M. Anwar H. Khan ◽  
Thomas J. Bannan ◽  
Carl J. Percival ◽  
Mark H. Lowenberg ◽  
...  

The chemistry of the nitrate radical and its contribution to organo-nitrate formation in the troposphere has been investigated using a mesoscale 3-D chemistry and transport model, WRF-Chem-CRI. The model-measurement comparisons of NO2, ozone and night-time N2O5 mixing ratios show good agreement supporting the model’s ability to represent nitrate (NO3) chemistry reasonably. Thirty-nine organo-nitrates in the model are formed exclusively either from the reaction of RO2 with NO or by the reaction of NO3 with alkenes. Temporal analysis highlighted a significant contribution of NO3-derived organo-nitrates, even during daylight hours. Night-time NO3-derived organo-nitrates were found to be 3-fold higher than that in the daytime. The reactivity of daytime NO3 could be more competitive than previously thought, with losses due to reaction with VOCs (and subsequent organo-nitrate formation) likely to be just as important as photolysis. This has highlighted the significance of NO3 in daytime organo-nitrate formation, with potential implications for air quality, climate and human health. Estimated atmospheric lifetimes of organo-nitrates showed that the organo-nitrates act as NOx reservoirs, with particularly short-lived species impacting on air quality as contributors to downwind ozone formation.


Media Wisata ◽  
2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ali Hasan Budi Hermawan

This paper reviews previous models of economic development of tourism using models such as pentahelix which generally focus more on how synergy and synchronization of government, academic, business, media, and tourism institutional actors, as well as the Tourism Satellite Account which methodologically measures only the end result tourism, while the power of the sector of economic potential and the transition of natural resource-based economic potential into a tourism-based economy has not been taken into account. Therefore such a perspective reflects only a narrative, but there is no model that mathematically explains the effect of the shift of the leading economic sector to GDP. Economic sustainability is a useful and useful purpose for human survival, therefore the model of economic development of tourism in the economic development of this society can complement the previous models, theoretically described the concept of economic development of tourism, model, measurement, program and indicators of development success tourism economy.


2021 ◽  
pp. 1-21
Author(s):  
CHUANFENG HUANG ◽  
RONG WANG ◽  
YAQIN SONG ◽  
PEIYU FENG

This paper proposes a two-dimensional conceptual model of inter-industry competitive pressure, which is constituted of resource competition and market competition. This paper also provides the related measurement method and some basic properties based on the perspective of input–output analysis. Empirical research in the U.S. clearly shows that these pressures obey a lognormal distribution with a power-law tail, and the proportions of the two-dimensional competitive components follow a normal distribution. This analytical framework can be used to explore the structural nature, statistical characteristics and evolutionary mechanism of the regional industrial competition system and provides some decision support for industry competition policies.


2021 ◽  
Author(s):  
Daniel J. Ruiz ◽  
Michael J. Prather

Abstract. Stratosphere-troposphere exchange (STE) is an important source of tropospheric ozone, affecting all of atmospheric chemistry, climate, and air quality. Observations and the theory of tracer correlations provide only coarse (±20 %) global-mean constraints. For fluxes resolved by latitude and month we rely on global chemistry-transport models (CTMs), and unfortunately, these results diverge greatly. Overall, we lack guidance from model-measurement metrics that inform us about processes and patterns related to the STE flux of ozone. In this work, we use modeled tracers (N2O, CFCl3) whose distributions and budgets can be constrained by satellite and surface observations, allowing us to follow stratospheric signals across the tropopause. The satellite derived photochemical loss of N2O on annual and quasi-biennial cycles can be matched by the models. The STE flux of N2O-depleted air in our CTM drives surface variability that closely matches observed fluctuations on both annual and quasi-biennial cycles, confirming the modeled flux. The observed tracer correlations between N2O and O3 in the lowermost stratosphere provide a seasonal, hemispheric scaling of the N2O flux to that of O3. For N2O and CFCl3, we model greater southern hemispheric STE fluxes, a result supported by some metrics, but counter to prevailing theory of wave-driven stratospheric circulation. The STE flux of O3, however, is predominantly northern hemispheric, but observational constraints show that this is only caused by the Antarctic ozone hole. Here we show that metrics founded on observations can better constrain the STE O3 flux which will help guide future model assessments.


2021 ◽  
Author(s):  
Yao Ge ◽  
Mathew R. Heal ◽  
David S. Stevenson ◽  
Peter Wind ◽  
Massimo Vieno

Abstract. Atmospheric pollution has many profound effects on human health, ecosystems, and the climate. Of concern are high concentrations and deposition of reactive nitrogen (Nr) species, especially of reduced N (gaseous NH3, particulate NH4+). Atmospheric chemistry and transport models (ACTMs) are crucial to understanding sources and impacts of Nr chemistry and its potential mitigation. Here we undertake the first evaluation of the global version of the EMEP MSC-W ACTM driven by WRF meteorology (1° × 1° resolution), with a focus on surface concentrations and wet deposition of N and S species relevant to investigation of atmospheric Nr and secondary inorganic aerosol (SIA). The model-measurement comparison is conducted both spatially and temporally, covering 9 monitoring networks worldwide. Model simulations for 2010 compared use of both HTAP and ECLIPSEE (ECLIPSE annual total with EDGAR monthly profile) emissions inventories; those for 2015 used ECLIPSEE only. Simulations of primary pollutants are somewhat sensitive to the choice of inventory in places where regional differences in primary emissions between the two inventories are apparent (e.g. China), but much less so for secondary components. For example, the difference in modelled global annual mean surface NH3 concentration using the two 2010 inventories is 18 % (HTAP: 0.26 μg m−3; ECLIPSEE: 0.31 μg m−3) but only 3.5 % for NH4+ (HTAP: 0.316 μg m−3; ECLIPSEE: 0.305 μg m−3). Comparisons of 2010 and 2015 surface concentrations between model and measurement demonstrate that the model captures well the overall spatial and seasonal variations of the major inorganic pollutants NH3, NO2, SO2, HNO3, NH4+, NO3−, SO42−, and their wet deposition in East Asia, Southeast Asia, Europe and North America. The model shows better correlations with annual average measurements for networks in Southeast Asia (Mean R for 7 species:  = 0.73), Europe ( = 0.67) and North America ( = 0.63) than in East Asia ( = 0.35) (data for 2015), which suggests potential issues with the measurements in the latter network. Temporally, both model and measurement agree on higher NH3 concentrations in spring and summer, and lower concentrations in winter. The model slightly underestimates annual total precipitation measurements (by 13–34 %) but agrees well with the spatial variations in precipitation in all four world regions (0.65–0.78 R range). High correlations between measured and modelled NH4+ precipitation concentrations are also observed in all regions except East Asia. For annual total wet deposition of reduced N, the greatest consistency is in North America (R = 0.75), followed by Southeast Asia (R = 0.68) and Europe (R = 0.61). Model-measurement bias varies between species in different networks; for example, bias for NH4+ and NO3− is most in Europe and North America and least in East and Southeast Asia. The greater uniformity in spatial correlations than in biases suggests that the major driver of model-measurement discrepancies (aside from differing spatial representativeness and uncertainties and biases in measurements) are shortcomings in absolute emissions rather than in modelling the atmospheric processes. The comprehensive evaluations presented in this study support the application of this model framework for global analysis of current and potential future budgets and deposition of Nr and SIA.


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