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Background: Rapid advances in mobile technologies and applications and the continued growth in digital network coverage have the potential to transform data collection in low- and middle-income countries. A common perception is that digital data collection (DDC) is faster and quickly adaptable. Objective: The objective of this study was to test whether DDC is faster and more adaptable in a roadside environment. We conducted a reliability study comparing digital versus paper data collection in 3 cities in Ghana, Vietnam, and Indonesia observing road safety risk factors in real time. Methods: Roadside observation of helmet use among motorcycle passengers, seat belt use among 4-wheeler passengers, and speeding was conducted in Accra, Ghana; Ho Chi Minh City (HCMC), Vietnam; and Bandung, Indonesia. Two independent data collection teams were deployed to the same sites on the same dates and times, one using a paper-based data collection tool and the other using a digital tool. All research assistants were trained on paper-based data collection and DDC. A head-to-head analysis was conducted to compare the volume of observations, as well as the prevalence of each risk factor. Correlations (r) for continuous variables and kappa for categorical variables are reported with their level of statistical significance. Results: In Accra, there were 119 observation periods (90-min each) identical by date, time, and location during the helmet and seat belt use risk factor data collection and 118 identical periods observing speeding prevalence. In Bandung, there were 150 observation periods common to digital and paper data collection methods, whereas in HCMC, there were 77 matching observation periods for helmet use, 82 for seat belt use, and 84 for speeding. Data collectors using paper tools were more productive than their DDC counterparts during the study. The highest mean volume per session was recorded for speeding, with Bandung recording over 1000 vehicles on paper (paper: mean 1092 [SD 435]; digital: mean 807 [SD 261]); whereas the lowest volume per session was from HCMC for seat belts (paper: mean 52 [SD 28]; digital: mean 62 [SD 30]). Accra and Bandung showed good-to-high correlation for all 3 risk factors (r=0.52 to 0.96), with higher reliability in speeding and helmet use over seat belt use; HCMC showed high reliability for speeding (r=0.99) but lower reliability for helmet and seat belt use (r=0.08 to 0.32). The reported prevalence of risk factors was comparable in all cities regardless of the data collection method. Conclusions: DDC was convenient and reliable during roadside observational data collection. There was some site-related variability in implementing DDC methods, and generally the productivity was higher using the more familiar paper-based method. Even with low correlations between digital and paper data collection methods, the overall reported population prevalence was similar for all risk factors.

The urgent need for alternative renewable energies to supplement petroleum-based fuels and the reduction of landfill sites for disposal of solid wastes makes it increasingly attractive to produce inexpensive biofuels from the organic fraction of the municipal solid waste. Therefore, municipal waste in the form of newspaper was investigated as a potential feedstock for fermentable sugars production. Hydrolysis of newspaper by dilute phosphoric acid was carried out in autoclave Parr reactor, where reactor temperature and acid concentration were examined. Xylose concentration reached a maximum value of 14 g/100 g dry mass corresponding to a yield of 94% at the best identified conditions of 2.5 wt% H3PO4, 135 degrees C, 120 min reaction time, and at 2.5 wt% H3PO4, 150 degrees C, and 60 min reaction time. For glucose, an average yield of 26% was obtained at 2.5 wt% H3PO4, 200 degrees C, and 30 min. Furfural and 5-hydroxymethylfurfural (HMF) formation was clearly affected by reaction temperature, where the higher the temperature the higher the formation rate. The maximum furfural formed was an average of 3 g/100 g dry mass, corresponding to a yield of 28%. The kinetic study of the acid hydrolysis was also carried out using the Saeman and the two-fraction models. It was found for both models that the kinetic constants (K) depend on the acid concentration and temperature. The degradation of HMF to levulinic acid is faster than the degradation of furfural to formic acid. Also, the degradation rate is higher than the formation rate for both inhibitors when degradation is observed.

An important strategy to promote a strong sustainable growth relies on an efficient municipal waste management, and phasing out waste landfilling through waste prevention and recycling emerges as a major target. For this purpose, effective collection schemes are required, in particular those regarding selective waste collection, pursuing a more efficient and high quality recycling of reusable materials. This paper addresses the assessment and benchmarking of selective collection schemes, relevant to guide future operational improvements. In particular, the assessment is based on the monitoring and statistical analysis of a core-set of performance indicators that highlights collection trends, complemented with a performance index that gathers a weighted linear combination of these indicators. This combined analysis underlines a potential tool to support decision makers involved in the process of selecting the collection scheme with best overall performance. The presented approach was applied to a case study conducted in Oporto Municipality, with data gathered from two distinct selective collection schemes.

The amount of municipal solid waste (MSW) has been increasing steadily over the last decade by reason of population rising and waste generation rate. In most of the urban areas, disposal sites are usually located outside of the urban areas due to the scarcity of land. There is no fixed route map for transportation. The current waste collection and transportation are already overloaded arising from the lack of facilities and insufficient resources. In this paper, a model for optimizing municipal solid waste collection will be proposed. Firstly, the optimized plan is developed in a static context, and then it is integrated into a dynamic context using multi-agent based modelling and simulation. A case study related to Hagiang City, Vietnam, is presented to show the efficiency of the proposed model. From the optimized results, it has been found that the cost of the MSW collection is reduced by 11.3%.

By using thermogravimetric analysis (TGA), the effects of different additives (MgO, Al2O3 and ZnO) on the pyrolysis characteristics and activation energy of municipal solid waste (MSW), paper sludge (PS) and their blends in N2 atmosphere had been investigated in this study. The experiments resulted that these additives were effective in reducing the initial temperature and activation energy. However, not all the additives were beneficial to reduce the residue mass and enhance the index D. For the different ratios of MSW and PS, the same additive even had the different influences. The catalytic effects of additives were not obvious and the pyrolysis became difficult with the increase of the proportion of PS. Based on all the contrast of the pyrolysis characteristics, MgO was the best additive and 70M30P was the best ratio, respectively.

SummaryWith the adoption of Computerized Patient Order Entry (CPOE), many physicians – particularly consultants and those who are affiliated with multiple hospital systems – are faced with the challenge of learning to navigate and commit to memory the details of multiple EHRs and CPOE software modules. These physicians may resist CPOE adoption, and their refusal to use CPOE presents a risk to patient safety when paper and electronic orders co-exist, as paper orders generated in an electronic ordering environment can be missed or acted upon after delay, are frequently illegible, and bypass the Clinical Decision Support (CDS) that is part of the evidence-based value of CPOE.We defined a category of CPOE Low Frequency Users (LFUs) – physicians issuing a total of less than 10 orders per month – and found that 50.4% of all physicians issuing orders in 3 urban/suburban hospitals were LFUs and actively issuing orders across all shifts and days of the week. Data are presented for 2013 on the number of LFUs by month, day of week, shift and facility, over 2.3 million orders issued.A menu of 6 options to assist LFUs in the use of CPOE, from which hospital leaders could select, was instituted so that paper orders could be increasingly eliminated. The options, along with their cost implications, are described, as is the initial option selected by hospital leaders. In practice, however, a mixed pattern involving several LFU support options emerged. We review data on how the option mix selected may have impacted CPOE adoption and physician use rates at the facilities. The challenge of engaging LFU physicians in CPOE adoption may be common in moderately sized hospitals, and these options can be deployed by other systems in advancing CPOE pervasiveness of use and the eventual elimination of paper orders.

Recycling of materials from municipal solid waste is commonly considered to be superior to any other waste treatment alternative. For the material fractions with a significant energy content this might not be the case if the treatment alternative is a waste-to-energy plant with high energy recovery rates. The environmental impacts from recycling and from incineration of six material fractions in household waste have been compared through life cycle assessment assuming high-performance technologies for material recycling as well as for waste incineration. The results showed that there are environmental benefits when recycling paper, glass, steel and aluminium instead of incinerating it. For cardboard and plastic the results were more unclear, depending on the level of energy recovery at the incineration plant, the system boundaries chosen and which impact category was in focus. Further, the environmental impact potentials from collection, pre-treatment and transport was compared to the environmental benefit from recycling and this showed that with the right means of transport, recyclables can in most cases be transported long distances. However, the results also showed that recycling of some of the material fractions can only contribute marginally in improving the overall waste management system taking into consideration their limited content in average Danish household waste.

The recovery and utilization of recovered paper have increased over past decades all over the world due to economic, environmental, and social issues. However, it is well known that an extended recovered paper collection is detrimental to its quality, either by the exploitation of lower quality sources such as households, or the spreading of commingled systems instead of selective collection systems. The influence of these two factors was assessed by analyzing the quality of different recovered paper grades used as raw material in a mill located in Madrid (Spain) producing newsprint and light weight coated paper from recovered paper. Part 1 of the paper deals with the impact of increased collection rates on the quality of recovered paper and Part 2 with the use of commingled collection systems. Results of Part 1 show that increased collection rates have a large impact on the quality of the recovered paper. The quality, measured as total unusable material and moisture contents, had deteriorated very rapidly in only four years (2005-2008) as a consequence of increased collection rates. Collection rates increased in Spain from 58.5% to 68.6% during this period, resulting in more than 50% increase of total unusable material and 25% of moisture content. The downgrading of the quality of recovered paper is one of the major threats for extending the current limits of paper recycling. Therefore, future challenge is to increase its availability but maintaining its quality.

Moisture distributions in municipal sewage sludge, printing and dyeing sludge and paper mill sludge were experimentally studied based on four different methods, i.e., drying test, thermogravimetric-differential thermal analysis (TG-DTA) test, thermogravimetric-differential scanning calorimetry (TG-DSC) test and water activity test. The results indicated that the moistures in the mechanically dewatered sludges were interstitial water, surface water and bound water. The interstitial water accounted for more than 50% wet basis (wb) of the total moisture content. The bond strength of sludge moisture increased with decreasing moisture content, especially when the moisture content was lower than 50% wb. Furthermore, the comparison among the four different testing methods was presented. The drying test was advantaged by its ability to quantify free water, interstitial water, surface water and bound water; while TG-DSC test, TG-DTA test and water activity test were capable of determining the bond strength of moisture in sludge. It was found that the results from TG-DSC and TG-DTA test are more persuasive than water activity test.

A review of results of the research involving the quantitative and composition analyses of household waste conducted in Poland in recent years is presented in this paper. For these analyses various methodologies have been employed, as there is not one obligatory methodology how to characterise municipal solid waste. The results of the research in large Polish cities indicate great variability, which is difficult to be reasonably explained. This situation is affected by a number of factors, such as various methods and places for sample collection, various methods for tests, fractional character of most of the studies (studies carried out only in some periods during a year). Consequently, it is neither possible to measurably compare their results, nor to generalise them. Hence, within this article only individual data for large cities is provided. It is therefore necessary to standardise methodology for such analyses in Europe, taking into account local variability (such as different housing patterns, climate and waste collection schemes) to allow comparison of results. Reported yearly household waste generation in Polish cities varies from 238 to 309 kg per inhabitant. Biodegradable waste is a strongly dominated fraction in household waste from Polish cities, followed by paper/cardboard and plastics. Historical data shows that waste composition has undergone profound changes, the most significant being an increase of the share of plastics and decrease of fine fraction. The presented data indicates that waste composition strongly depends on the type of housing and its heating system. In the new multi-family buildings with central heating the share of paper and plastics is higher than in old houses with individual heating. In the latter ones the share of fine fraction is higher.

Inorganic urban solid waste (IUSW) is a serious problem in developing countries, and IUSW in the street that does not have adequate final disposal is responsible for serious environmental effects. The aim of this work was to determine the dynamics of the generation of IUSW in the streets of two neighborhoods of different socioeconomic strata in Mexico City during 5 weeks in 2006. The amount of IUSW was recorded every day from 9:00 to 12:00 h, separated, classified, and registered. It was found that plastic (50%) and paper (44.5%) wastes were found most frequently, whereas, textiles (0.4%) and glass (0.5%) wastes were present less frequently in all samples. The IUSWs without commercial brands were more abundant. Branded plastic wrappers of PepsiCo and Bimbo, as well as polyethylene terephthalate (PET) containers of Coca Cola, registered the highest values, while Gatorade, Barrilitos, and Peñafiel registered the lowest. The neighborhood with a higher income and more vegetation on sidewalks or in jardinières, which are used to hide solid waste, had more IUSW than the neighborhood with lower income, where IUSW was thrown out directly into the street. The knowledge of the real generation and composition of IUSW will contribute to the prevention of its negative environmental and social impacts, as well as guarantee the efficiency of its sustainable management.

This paper analyzes the generation and composition of municipal solid waste in Spanish towns and cities with more than 5000 inhabitants, which altogether account for 87 % of the Spanish population. To do so, the total composition and generation of municipal solid waste fractions were obtained from 135 towns and cities. Homogeneity tests revealed heterogeneity in the proportions of municipal solid waste fractions from one city to another. Statistical analyses identified significant differences in the generation of glass in cities of different sizes and in the generation of all fractions depending on the hydrographic area. Finally, linear regression models and residuals analysis were applied to analyze the effect of different demographic, geographic, and socioeconomic variables on the generation of waste fractions. The conclusions show that more densely populated towns, a hydrographic area, and cities with over 50,000 inhabitants have higher waste generation rates, while certain socioeconomic variables (people/car) decrease that generation. Other socioeconomic variables (foreigners and unemployment) show a positive and null influence on that waste generation, respectively.

This paper deals with the characteristics and composition of municipal solid waste (MSW) generated in Sangamner city. The composition of solid waste was studied by segregating it into different component, i.e., kitchen waste, paper, earth and fine material, slaughter house waste, leaves, metals, etc. These components were categorised into organic waste and inorganic waste. It was observed that Sangamner city produces around 61% organic waste, and the rest is inorganic waste. The characteristics of organic solid waste, i.e., pH, electrical conductivity, moisture content, organic carbon, nitrogen, phosphorus and potassium were evaluated. The analysis of organic content of MSW indicates that it is good source of nutrients for the agriculture sector whereas inorganic material can be used for landfill.

Article, WASTE MANAGEMENT. 29(3):1192-1197 (2009)

Local authorities need updated and reliable data on the quantity and the quality of the waste generated in their area, in order to establish an integrated solid waste management system capable of fulfilling regional and national waste management targets. This paper presents information about the quantity and the characteristics of the municipal solid waste generated in Thessaloniki, which is the second largest city in Greece. It is based on the results of three research programs investigating the evolution of municipal solid waste. The investigations were carried out over the last 20 years at the landfill of Thessaloniki by the same research group using statistically acceptable practices for sampling and hand sorting. The results show a great increase in the incoming quantities during the last years and a significant increase of the per capita generation. There is also a significant change in the composition, demonstrated mainly by a decrease in the organic fraction followed by an increase of packaging materials (paper and plastic).

The effects of joint openings and in-pipe sediment on exfiltration losses in an experimental sewer are reported and the influence of flow and head on loss rates are also evaluated. Exfiltration rates tend to be exponential with changes in head for clean-water tests but exhibit power functions when the pipe is subject to sedimentation. In-pipe sediment leads to an effective sealing of joints especially if the invert deposits are both organic in nature and contain saturated adhesive material such as shredded toilet tissue. Simple tracer techniques are described to quantify exfiltration losses and the potential effects of tracer adsorption by pipe solids are evaluated.