bluuebunny/crossref_metadata_2025 huggingface dataset:
1984 Macromarketing Seminar Abstracts
Authors: Klein Thomas A.
Published: November 2009

The 1984 Macromarketing Seminar was hosted jointly by the University of British Columbia and Simon Fraser University at Vancouver, British Columbia, Canada, August 16-19. Nearly 50 participants met to discuss macromarketing research and theory. The Call for Papers included a special request for work on the role of marketing in economic development. Abstracts of papers formally presented at the seminar follow. Readers wishing complete copies of these papers may request them directly from authors.

The Tenth Macromarketing Seminar will be held in Washington, D.C., following the American Marketing Association Educators Conference, in August 1985.
Geographies of tourism: (un)ethical encounters
Authors: Gibson Chris
Published: November 2009

In this report I focus on encounter, and the manner in which tourism catalyses entanglements of people, places and identities. Antecedent were earlier theories of the tourist gaze, and critiques of tourism as neocolonialism. One response was the emergence of an ethical tourism industry — branded as such because of commitments to pay decent wages, respect local cultures and tread lightly on nature. While the ethical tourism industry has made strides on these issues, I critique its reliance on binary thinking, and failure to accommodate contradictions and variable ethical conduct in the moments of encounter. By contrast, recent work in geography has sought to explore the multisensory and affective dimensions of tourism encounters without recourse to ethical essentialism. In research on embodiment, emotions and sensory encounters, risks of diluting critique are weighed against opportunities to sharpen ethical concepts. A focus on encounter enables closer dissection of the moments and spaces in which power is exercised, and relations of care extended.
Effect of operating conditions and input variations on the partitioning of metals in a municipal solid waste incinerator
Authors: Morf Leo S. , Brunner Paul H. , Spaun Sebastian
Published: November 2009

The partitioning of copper, zinc, cadmium and lead between bottom ash and combustion flue gas was investigated in a municipal solid waste (MSW) incinerator. Material balances were established and transfer coefficients were determined for seven 2-h periods. Statistical analysis of the data allowed assessment of the uncertainty and investigation of the effect of waste input variations as well as process conditions. As a result, 6% of Cu, 54% of both Zn and Pb and 90% of Cd in the waste feed were transferred into the combustion flue gas, the rest was found in the bottom ash. The uncertainty of the partitioning in terms of relative width of 95% confidence intervals was estimated as 33% for Cu, 7% for Zn, 7% for Cd and 21% for Pb. Multiple linear regression indicates that, for the incinerator investigated, changes in combustion parameters have a negligible effect on the transfer coefficients of the selected metals; and the partitioning of Cd and Pb does not correlate significantly with changes in the waste composition. A significant positive regression between the transfer of Cu and the chlorine content of the waste feed was observed. The results of this study are instrumental to determine the waste composition by analysing a single combustion product only.
Assessment of two different separation techniques for building wastes
Authors: Schachermayer Elisabeth , Lahner Theresia , Brunner Paul Hans
Published: November 2009

It is a well known fact that construction and demolition wastes (C and D wastes) make up 50% of municipal wastes in countries with a high gross domestic product (GDP). Besides questions about the handling of such enormous amounts of waste, problems also occur with the chemical composition of the C and D wastes. The latter problem is the result of the increasing use of synthetic organic materials and heavy metals in construction engineering during the last decades. In this paper two different treatment technologies for C and D wastes are compared, a wet and a dry separation technique. The comparison yielded the following results: both dry and wet technology are not able to select materials according to their chemical composition with the exception of iron, organic carbon and water soluble substances (in the case of wet sorting). Further, it is shown that there are only small differences in the produced fractions of the two plants. Both plants produce a small grain size fraction with the highest content of trace elements, which should be removed prior to reuse. It became obvious that the (chemical) quality of the input is the most important factor in view of the quality of the output fractions. Consequently, this makes separation of C and D wastes at source, a necessity on the way to multiple recycling steps.
Improvement of municipal solid waste quality for landfilling by means of mechanical-biological pretreatment
Authors: Zach Alexander , Binner Erwin , Latif Muna
Published: November 2009

Municipal solid waste (MSW) was accompanied through a mechanical-biological treatment plant. Over a period of 20 weeks samples were taken at different stages of treatment. Samples were analysed for physico-chemical parameters, reactional behaviour (respiration activity, gas-generating potential) and toxic effects (aquatic toxicity). Results showed that reactional behaviour decreased considerably with the duration of treatment. Gas-generating potential and respiration activity were reduced for more than 90% at the end of the composting process. Total organic carbon (TOC), chemical oxygen demand (COD), biological oxygen demand (BOD5) and ammonia decreased as well. High toxicity could be obtained with the input and short pretreated materials, the output material did not show any toxic effects at all. The results indicate that aerobe treatment of MSW reduces emission behaviour significantly and less reactive waste is left for landfilling.
End-of-life electric and electronic equipment management towards the 21 st century
Authors: Shunli Zhang  , Forssberg Eric , van Houwelingen Jan , Rem Peter , Wei Liu-Ying
Published: November 2009

With the rapid growth of the electronics industry and an ever-growing environmental awareness world-wide, an environmentally sound and economically viable management system for end-of-life (EOL) electric and electronic equipment (EEE) is of great importance for sustainable development. Traditional recycling and processing of EOL electronics directed towards the recovery of copper and precious metals, will be faced with many challenges in the future. It has been recognized by the EOL EEE recycling industry that a new strategy for EOL EEE must be developed. In this paper, current status and future trends in EOL EEE management are presented. Selective dismantling of valuable and hazardous components is evaluated in terms of a grade-recovery (GR) concept. It is concluded that selective dismantling and mechanical processing must be coordinated in such a way as to produce suitable materials for subsequent handling at the lowest cost. Furthermore, new developments in mechanical and thermal processing of EOL EEE are also discussed, which involve water table and eddy current separation techniques and reduction of dioxins and furans during combustion of the plastics containing halogenated flame retardants. In addition, the challenges and perspectives associated with EOL management of plastics and cathode ray tubes (CRTs) encountered in EOL EEE are highlighted in this paper. It is predicted that EEE, being designed for recycling in the 21st century, will be processed and recycled economically and ecologically on becoming obsolete.
A comparative study of the leachates produced by anaerobic digestion in a pilot plant and at a sanitary landfill in Asturias, Spain
Authors: Rodríguez Iglesias J. , Castrillón Peláez L. , Marañón Maison E. , Sastre Andrés H.
Published: November 2009

Leachates produced in a simulated landfill pilot plant were compared with those produced at the Zoreda landfill in Asturias, Spain. Three loads of different amounts of municipal solid waste (MSW) were added to the pilot plant at different stages, thus forming consecutive layers. Up to the present, approximately 3 333 000 t (metric tons) of MSW have been deposited in the landfill in 2.5 m high layers which are covered with soil from the surrounding area. The organic load of the leachates as COD decreased with time in both systems from very high initial values to relatively low ones by the end of the study, although they were higher in the actual landfill (approximately 4 g as opposed to 1.5 g O 2 dm-3 in the pilot plant). The pH decreased initially to values close to 6, but then increased to around 8. Ammoniacal-N (ammoniacal nitrogen) concentrations were high in both systems whereas metal concentrations were low.
Qualitative methods add value to waste characterization studies
Authors: Newenhouse Sonya C. , Schmit Joan T.
Published: November 2009

In order to develop effective waste management plans for a community, an understanding of the composition and quantity of waste in question is required. Quantitative research methods, such as traditional waste characterization studies, have typically been used to provide relevant data. Purely quantitative methods, however, involve limitations. The purpose of this paper is to describe the integration of qualitative methods, such as open-ended interviews and field observation, with quantitative waste characterizations to study communities' waste streams. In a test study at Madeline Island, Wisconsin (USA), many benefits were realized using this integrated approach to waste stream analysis. Benefits relating specifically to the data collection process include the discovery of: new information, site specific details, explanations of waste stream conditions, and potential solutions for reusing, reducing and recycling currently disposed waste materials. The incorporation of qualitative methods was also beneficial in decreasing research biases and provided the added value of increasing community members' awareness of their waste through engaging them in the research process. Detriments of the integrated approach generally rest on cost, yet potential solutions to this issue also exist.
Modelling of waste collection - a general approach to calculate fuel consumption and time
Authors: Sonesson Ulf
Published: November 2009

A model for calculating time and energy consumption during the collection of waste with compacting trucks is presented. The model uses common statistics from a number of households in three different categories of residential area: the average distance from the residential area to treatment facility/transfer station, fuel consumption per km for the truck and average load and speed. This common and easily accessible information is completed with figures for time and energy consumption related to the extra work that is performed on account of stopping and emptying bins. Default values for those parameters are presented in this paper, estimated using data from a Swedish municipality. Data from four areas in Sweden were used for verification. The model predicts the real outcome relatively well: between 5 and 14% deviation for energy consumption and between 10 and 24% deviation for time consumption.
Selective collection of glass containers in the Valencian Community (Spain)
Authors: Llopis González A. , La Orden Gil A. , Morales Suárez-Varela M.M. , Polanco Villalba B.
Published: November 2009

Spanish legislation has recently adopted the norms defined by a directive of the European Parliament and the Council of Ministers, 20 December 1994, concerning containers and container residues. The purpose of the directive is to harmonize national measures for the processing of these products in member states. Thus, contributing to prevent or reduce their impact upon the environment both in the different member states and in third countries. To this effect, the directive requires the compliance within a given period of a series of recycling and processing objectives applicable to all the packaging and container materials on the market, including glass products. The aims of the present study included an evaluation of the selective collection of glass waste products in the Valencian Community (Spain), in order to determine the degree of compliance with the above mentioned recycling objectives. The results obtained show that 24.54% of all municipalities within the triple-province of the Valencian Community fail to comply with these measures, thereby generating changes in the selective collection of such materials.
Xylanase activity and thermostratification during the thermogenic phase of industrial composting in aerated trenches
Authors: Lyon Pierre-François , Beffa Trello , Fischer Johanna Lott , Aragno Michel
Published: November 2009

Extracellular xylanase activity and thermostratification were monitored during the thermogenic phase of industrial composting (mainly garden waste) in aerated trenches. Xylanase activity was assayed at different temperatures and pH by incubation of clarified compost extracts with xylan. The highest xylanase activity and temperatures were measured during the summer (when waste was rich in freshly cut grass). Xylanase activity was higher in the peripheral layers of the trenches, at moderately high temperatures (48 to 68°C), than in the hottest central layers (70 to 78°C). Optimal temperature for the xylanases was between 60 and 80°C at pH 6, depending on the temperature of the sampling site. The thermostability of the xylanases from surface samples was high until 60°C, moderate at 70°C and weak at 90°C. Our results show a broad thermostratification of the compost mass. Frequent turnings of the compost stimulate xylan degradation by redistributing the substrates, the free enzymes and the microorganisms.
Report: Waste management as a challenge for a laboratory in the rain forest of Ecuador
Authors: Zach Alexander
Published: November 2009

Many developing countries suffer from a lack of collection, treatment and disposal systems for waste. A laboratory in the Amazon basin of Ecuador took the initiative and tried to handle a rising waste problem itself. Solutions for the recycling, treatment and harmless deposition of chemical wastes were developed and applied. Acidic and basic solutions, representing the majority of chemical residues, were disposed of or added to the waste water system after neutralization. The organic solvents could partly be recovered by rectification; others could be re-used. Dissolved heavy metals were precipitated and immobilized in concrete. Cyanides were destroyed and residues of microbiological analysis were thermally detoxified, as were oil-polluted soil samples and irrecoverable organic solvents. Although a description of a particular case, many of these easily applicable solutions could be appropriate for small enterprises or laboratories in a similar situation.
Accelerated hydrolysis and acidification of municipal solid waste (MSW) in a flushing anaerobic bio-reactor using treated leachate recirculation
Authors: Wang Z. , Banks C.J.
Published: November 2009

The efficiency of anaerobic digestion for reducing the solid content of the organic fraction of municipal solid waste (OFMSW) was compared using a conventional single pass reactor (SPR) and a two stage anaerobic-aerobic process. The first stage of the two stage system used an anaerobic hydraulic flush reactor (HFR) in which the solids and liquid retention times were decoupled by retention of solids within the system. The purpose of the hydraulic flush was to wash out rapidly the fermentation intermediates from the anaerobic reactor and thus prevent their accumulation; these were subsequently removed in the second stage aerobic activated sludge system, the effluent from which was then used as the flush liquor to the first stage. The hydraulic flush reactor was operated at hydraulic (liquid) retention times of 2, 3 and 4 days with solids retention times of 30, 25, 20, 15, 10 and 5 days. In all cases the total solid content in the feed was 10% giving loading rates to the reactor in the range 3 to 21 kg total solids per m3 day; this same loading range was used in the single pass reactor. At high loadings the SPR system showed an accumulation of volatile fatty acids, peaking at 13000 mg 1-1, which resulted in process failure and cessation of solids destruction. At the same process loadings the HFR system showed only a slight decline in the rate of solids destruction when using a high hydraulic flush rate.
Changes in the phosphorus availability of a chemically precipitated urban sewage sludge as a result of different dewatering processes
Authors: Kvarnström Elisabeth , Morel Christian , Fardeau Jean-Claude , Morel Jean-Louis , Esa Sahib
Published: November 2009

The objective of this study was to compare the effects of different dewatering processes on the phosphorus (P) availability of an FeCl3-precipitated and lime-conditioned sludge having an initial dry matter content (DMC) of 4%. The sludge was dewatered by either drying (D), freezing/ thawing (FT) or centrifugation (C) until a DMC of about 15% was reached. Thereafter the FT and D sludges were gently dried to obtain a DMC increasing up to 50 to 60%. The plant-available sludge P was assessed by the change in the isotopic dilution of P taken up by ryegrass (Lolium perenne [L]) after sludge amendments to one soil. After the plant experiment, the soil-to-solution transfer of P ions and bicarbonate-and ammonium lactate-extractable P were determined in selected soil samples. The amount of plant-available P (L-value) and the contribution of sludge P to plant nutrition (% Pdfsl) in soil amended with non-dewatered sludge (ND) were not significantly different from the L and percentage Pdfsl values of soils amended with FT, D and C sludges. Nor did the subsequent drying of D and FT sludges significantly change the L and percentage Pdfsl values. Hence, the dewatering processes did not significantly alter the initial sludge P availability. The soil-to-solution transfer of P ions and the chemically extracted P did not significantly differ between the different sludge-amended soil samples. The percentage Pdfsl values can be predicted by percentage Δ E1, since the overall average relative increase (%Δ E1) in the immediate soil-to-solution transfer of P ions did not significantly differ from the percentage Pdfsl values.
Biosolid effects on soil and native plant production in a degraded semiarid ecosystem in central Spain
Authors: Walter I. , Cuevas G. , García S. , Martínez F.
Published: November 2009

Anaerobically digested biosolid was surface-applied at three rates, 40, 80 and 120 Mg ha-1, to a degraded semiarid ecosystem of the central region of Spain to determine the effects of biosolids on soil chemical properties, total plant cover and total above ground biomass 1 year after its application. Biosolid amendment had little impact on soil chemistry and nutrient levels. However, available P and N-NO3 increased significantly after application of biosolids. The concentration of total soil heavy metals, Zn, Pb, Cd, Ni, Cr and Cu increased with the application of biosolids as compared against the control plot, but these increases were not statistically significant. The levels of DTPA-extractable soil heavy metals did not change in the treated plots. Total plant cover and total biomass production increased significantly in the biosolid treated plots. The most favourable soil and vegetation results were found in 40 and 80 Mg ha-1 biosolid application rates.
Modelling commercial/industrial waste generation: a Vienna, Austria case study
Authors: Salhofer Stefan
Published: November 2009

A study was done to determine in greater detail the volume of recyclable materials, sector-specific wastes and residual wastes from businesses within the Vienna city limits. To do so, a matrix-type model was applied to classify businesses according to commercial/industrial sector and business size. For small and medium-sized businesses, random samples were taken directly to determine average amounts and types of wastes generated; these figures were then extrapolated based on the number of employees. For large businesses, data taken from obligatory Waste Management Concepts were evaluated and augmented with an extrapolation. Because waste disposal channels were examined along with the volumes of wastes generated, it is possible to determine the impacts on the municipal collection system. The results are compared with data from the literature and other studies.
Kinetic analysis of forced aeration composting- II. Application of multilayer analysis for the prediction of biological degradation
Authors: Bari Quazi H. , Koenig A.
Published: November 2009

Extensive pilot-scale composting tests for organic solid waste were conducted under different modes of aeration, to investigate vertical temperature distributions and their effect on biological degradation at different heights of the composting mass. The modes of aeration applied were upflow, downflow, alternate upflow/downflow, and internal air recirculation. Temperatures at different heights of the composting mass were continuously monitored. Results show that (i) significant variation in temperature and biodegradable volatile solids (BVS) degradation occur in the composting mass along the vertical direction when unidirectional aeration is applied; (ii) application of alternate upflow/downflow aeration or periodic mixing greatly reduces vertical gradients in temperature and biodegradable volatile solids (BVS) degradation; and (iii) the rate and extent of degradation in different layers of the composting mass can be quantitatively predicted by applying a combination of multilayer analysis and a previously established temperature-dependent first-order reaction model.
Waste recycling in Malaysia: problems and prospects
Authors: Mohd Nasir Hassan  , Rakmi Abdul Rahman  , Theng Lee Chong  , Zakaria Zulina , Awang Muhamad
Published: November 2009

Recycling of solid wastes should be integrated into the existing and future waste management plans so as to yield the benefits of conservation of natural resources, saving of fossil fuels and prolonging lifespan times of disposal sites. This paper discusses the current status of waste recycling in Malaysia and its future prospects. Although a large amount of Malaysian wastes could be recycled, less than 5% of the total (almost 10 000 t d-1) is actually separated and recycled. There is a good demand for waste plastics, paper and glass, with resale prices of about US$60 t-1, US$44 t-1 and US$32 t-1, respectively. Recovery of only 5% of the available waste plastics, paper and glass is estimated to yield a total of about US$3.4 million y-1. Recommendations to increase recycling are discussed in the paper.
Optimization studies of waste plastics-lignite catalytic coliquefaction
Authors: Gimouhopoulos K. , Doulia D. , Vlyssides A. , Georgiou D.
Published: November 2009

The optimization studies of an investigation for waste plastics-lignite catalytic coliquefaction are reported in this paper. At first, two SiO2 supported, Pt-Co and Pt-Mo promoted bimetallic catalysts were prepared. Next, catalytic coliquefactions were attempted on 1/1 mixtures of lignite and waste polymers, e.g. polystyrene, polyisoprene and polyethylene in the presence of various organic solvents. Taking into consideration the results obtained from the variables examined, two newer series of experiments were designed and undertaken aiming at the optimization of this complex transformation. In the first series, the best performing catalyst and the selected most-effective waste plastics were employed and different mixtures of the two more active solvents were added. In the second series, coliquefactions of the precedent mixtures in two stages was attempted in order to optimize overall conversion so far attained. It was found that the mentioned catalytic coprocessing is an interesting form of hydrocarbon synthesis, although the efficacy of the conversion achieved was influenced by the chemical characteristics of the polymers added and of the solvents employed.
Recovery of chromate from electroplating sludge
Authors: James Matthew G. , Beattie James K. , Kennedy Brendan J.
Published: November 2009

Recycling chromium from electroplating waste sludge is attractive both economically and environmentally. Oxidizing chromium(III)-containing electroplating waste with aqueous oxidants in alkaline suspensions did not allow complete recovery of the chromium. Hypochlorite was potentially a suitable oxidant as it could completely oxidize a suspension of chromium(III) hydroxide to chromate at basic pH. From sludge, however, only up to 85% of the chromium was recovered; complete recovery was not achieved despite different experimental conditions and procedures. The unrecovered chromium was found by X-ray photoelectron spectroscopy to have been oxidized and is most likely present as insoluble metal chromates trapped in the sludge. Roasting the sludge followed by aqueous leaching, however, enabled complete recovery of the chromium.
The effects of moisture inputs on landfill gas production and composition and leachate characteristics at the Vancouver Lanclfill Site at Burns Bog
Authors: Wreford K.A. , Atwater J.W. , Lavkulich L.M.
Published: November 2009

Infiltration of water into a landfill affects the process of waste decomposition. An analysis of variation in landfill gas production and composition (%CH4, %CO2) in response to precipitation variations was carried out at the Vancouver Landfill Site at Bums Bog. Results indicate a direct relationship between cumulative precipitation 14 days prior to sampling and CH4 generation (mean r2 = 0.88). This finding suggests that a time lag is in effect, wherein the moisture acts to enhance CH4 production. The ratio of CH4:CO2 production showed a strong direct relationship to cumulative precipitation 7 days prior to sampling ( r2 = 0.85). It is possible that the CO2 acts as an end-product inhibitor during acetate and propionate degradation; therefore, decreased CO2 partial pressures after periods of heavy rainfall would favour enhanced CH4 production.
Relative significance of environmental factors affecting hydrogen production from landfilled refuse samples
Authors: Gurijala Koteswara R. , Ping Sa  , Mormile Melanie R.
Published: November 2009

The relative significance of 11 environmental factors on the apparent steady-state concentration of hydrogen (ASSCH2) achieved during anaerobic degradation of refuse collected from landfills was evaluated by using multiple regression analysis. Simple correlation analysis revealed a significant negative association of ASSCH2 with newsprint moisture content (NMO) and pH of the sample. Application of five different variable selection procedures, which are commonly used in multiple regression analyses, showed that NMO, amylase (AMY), esterase (EST), cellulose to lignin ratio (CLR), volatile solids (VS), and nitrogen content (NIT) were significantly associated with ASSCH2 simultaneously. The other five factors did not show any significant effect on ASSCH 2 in the presence of the six significant factors. Further analysis showed that the influence of AMY and EST on ASSCH2 was weak, hence they were not included in the regression model. CLR was also deleted from the final model because of the multicollinearity resulting from its high correlation with VS. The final model incorporated NMO, NMO2, VS2 and NIT2; it explained 95% of the total variability and predicted 98% of the observed ASSCH2. An assessment of the relative significance of the independent variables indicated that NMO contributed the most, followed by NMO2 and VS2, in that order, and the least by NIT2 towards ASSCH2. The NMO and NIT 2 showed an inhibitory effect on ASSCH2. The results indicated that maintaining optimum moisture, along with optimum organic loading, and nitrogen content in landfills is necessary to achieve and maintain a low ASSCH2 and maximize refuse methanogenesis.
Use of petroleum-contaminated drilling wastes as sub-base material for road construction
Authors: Tuncan Ahmet , Tuncan Mustafa , Koyuncu Hakan
Published: November 2009

In this study, petroleum-contaminated drilling wastes were stabilized by mixing pozzolanic fly ash, lime and cement with them so they could be used as sub-base materials for road construction. This stabilization produced physically, mechanically and chemically stabilized new mixtures. The laboratory study consisted of unconfined compressive strength, permeability, California bearing ratio, freeze/thaw (durability) and leachate on compacted stabilized samples, pH, electrical conductivity, cation exchange capacity and total metal contents on stabilized mixtures. Significant increases in the unconfined compressive strength, California bearing ratio, durability and pH were obtained by treating lime, fly ash and cement with petroleum drilling wastes. Significant decreases were obtained in electrical conductivity, cation exchange capacity, oil content and total metal concentrations both in mixtures and in leachate. The best result in all of the tests conducted was obtained with petroleum-contaminated soil stabilized with 20% lime, 10% fly ash and 5% cement. This mixture can be effectively and safely used as sub-base material.
Cost-benefit analysis of introducing technology to rapidly degrade municipal solid waste
Authors: Clarke William P.
Published: November 2009

Due to an increasing awareness of the true economic and environmental cost of conventional landfilling, recent interest has developed in Australia in technologies that accelerate the degradation of the organic fraction of municipal solid waste (MSW). The management of the organic waste stream, which typically makes up 60 to 70% of MSW in Australia, is central to reducing the reliance on landfill space. One option is to digest the organic fraction prior to landfilling, or preserve landfill space by accelerating the decomposition of the organic fraction within the landfill. This paper quantifies the benefits of digestion as a function of the degradation time, td. The analysis considers both invessel and landfill-based bioreactor technologies and calculates net economic impact, expressed as $US t-1 MSW, as the sum of enhanced and more rapid biogas retrieval, saved landfill space, reduced environmental disamenity and reduced postclosure costs, minus the capital and operating costs to implement the technology. The benefits, on a per tonne basis, are shown to be insensitive to the size of the waste stream while costs diminish as the waste stream size increases. A conventional landfill with td = 20 yr is used as a basis of comparison. At 1800 t day-1, the maximum level of benefit is 13 $US t-1 at td = 2 months, diminishing monotonically to zero at td = 20 yr. The cost of achieving td = 2 months is the cost of invessel digestion, estimated to be 99 $US t-1, resulting in an overall increase of 86 $US t -1 in waste management costs. Similarly, degradation times of 2 < td < 5 yr provide a benefit of 8 to 11 $US t-1 for a waste stream of 1800 t day-1. This rate of degradation can be achieved with landfill-based bioreactor technology. The cost of additional infrastructure needed to implement accelerated degradation, such as pretreatment pads, internal leachate distribution networks and additional gas wells and generators, is estimated to be less than 1 $US t-1. Bioreactor technology is therefore appealing, although their is uncertainty about the additional operating costs needed to run a landfill as a bioreactor. Additional operations would mainly revolve around segmenting the waste mass to tightly control leachate distribution. The cost of these additional operations are unlikely to exceed the operating cost of a modern conventional landfill, estimated at 9 $US t-1. Therefore, landfill bioreactor technology should be cost effective.
Modelling national solid waste management
Authors: Ljunggren Maria
Published: November 2009

The MWS model (MIMES/Waste for Sweden) is a systems engineering model for strategic planning of national solid waste management systems. It was developed for Sweden, but the general approach can be applied to other countries as well. The MWS model integrates cost minimization and emissions accounting and is intended for evaluating, from economic and environmental points of view, waste treatment technologies and waste management policies. The potential users of the model are, e.g. government agencies, companies, trade associations and funding authorities. In the MWS model, the Swedish waste management system is represented by 10 generalized municipal waste management systems. The integration of the generalized systems into a national model allows an analysis on a national level as well as on a generalized municipal level. A case study of the Swedish solid waste management system illustrates the application of the MWS model.
Solid waste management solutions for Semarang, Indonesia
Authors: Supriyadi Slamet , Kriwoken Lorne K. , Birley Imogen
Published: November 2009

Semarang, the capital city of the Central Java Province, Indonesia, has been struggling to overcome its municipal solid waste problem. The current waste disposal system covers about 60% of the total waste generated. The paper begins by introducing the solid waste problem in Semarang with particular attention to the Five Year Development Plans. The Adipura program is introduced and recent measures for improving urban infrastructure assessed. The socioeconomic role of scavengers in the waste management process is detailed and the existing solid waste management system in Semarang is critiqued. The paper then introduces the Semarang study area. Waste characteristics are examined and the market value of recyclable materials is estimated at about Rp. 8 billion ($A 3.6 million) per year. The socioeconomic importance of scavengers is recognized in the reduction of domestic solid waste. The final section of the paper recommends that Semarang should consider source separation, home and large-scale composting as a means to deal with its solid waste problem.
Pentachlorophenol degradation in landfill drainage models
Authors: Kostova Irina , Todorova Ivanka
Published: November 2009

The paper describes a laboratory experiment on the biological activity of bacterial populations derived from landfill waste and established on granular materials under conditions similar to those in a landfill drainage system. Two perspex laboratory columns were used to model the landfill drainage system. Artificially formulated leachate was recycled through the columns and the composition of the leachate and the gas produced was measured.

The objectives of the research are to show that the landfill drainage system model can act as a fixed bed anaerobic reactor producing gas and to investigate the effect of a hazardous chemical, pentachlorophenol in particular, on microbial activity and the potential for its degradation by bacteria.

The results have shown that bacteria derived from landfill waste and established once on landfill drainage aggregates have the ability to survive at low levels of activity and rapidly revive after the addition of nutrients in the form of recirculating leachates.
A Paradox in Pattern Analysis
Authors: Silverstein A. B.
Published: November 2009

Intuition suggests that when the score on one subtest is compared with the average score on a group of subtests, the outcome ought to depend on whether the score in question is included in or excluded from the average. In fact, it does not. The equivalence of the two procedures, inclusion and exclusion, is demonstrated for three varieties of pattern analysis. In addition, some historical observations are offered that testify to the almost irresistible intuitive appeal of the notion that inclusion or exclusion does make a difference.
Confirmatory Factor Analysis of the WAIS-R: Plausibility of Models
Authors: Plake Barbara S. , Gutkin Terry B. , Kroeten Terrence
Published: November 2009

A confirmatory factor analysis was used to determine the respective viability of factor structure models for the WAIS-R standardization data. The traditional Verbal-Performance split was compared to an alternative model proposed by Gutkin, Reynolds, and Galvin (1984). The confirmatory analysis indicated that the Gutkin model provides a superior fit to the data at all age levels and for the total sample. In addition, the results from Gutkin model analyses at each age level were iterated, yielding a refinement in the respective age-specific fits of the model. Implications for test interpretation are discussed.
The Validity of Bannatyne's Acquired Knowledge Category as a Separate Construct
Authors: Matheson David W , Mueller Horst H. , Short Robert H.
Published: November 2009

The validity of Bannatyne's recategorization of WISC-R subtests was tested by applying multiple group factor analysis to the intercorrelation matrices of the 7.5-, 10.5-, and 13.5-year samples from the WISC-R standardization. Although the Acquired Knowledge category had a high reliability coefficient, it was almost completely linearly dependent on the other categories, particularly Conceptualization. Consequently, differences between these two categories will be unreliable. It was concluded that scores on Acquired Knowledge provide no unique information, and their interpretation as a measure of educational attainment, apart from verbal ability, was discouraged.
Comparison of Three Intelligence Tests as Predictors of Academic Achievement and Classroom Behaviors of Mexican-American Children
Authors: Johnson Dale L. , McGowan Ronald J.
Published: November 2009

The school performance of low-income Mexican-American children was predicted from scores on three intelligence tests. The Stanford-Binet (S-B) was given at 3 years, S-B and McCarthy Scales of Children's Abilities (MSCA) at 4 years, and the Wechsler Intelligence Scale for Children-Revised (WISC-R) at 7-9 years. School grades, Iowa Test of Basic Skills (ITBS) scores, and the Classroom Behavior Inventory (CBI) comprised the school performance measures. Grades were predicted significantly by S-B, but there were no significant correlations for the other tests. All the intelligence tests had some significant correlations with some of the ITBS and CBI scores. The S-B and MSCA were about equal as preschool predictors of ITBS and CBI scores. The controversy over the value of the WISC-R in assessing minority-group children was discussed in view of the finding that WISC-R scores were significantly correlated with the ITBS but not with grades.
A Search for the Mathematical Component of Math Anxiety
Authors: Kagan Dona M.
Published: November 2009

This study tested the hypothesis that numeric anxiety is associated with rigidity in problem solving and with deficiencies in spatial skills. Subjects were 204 college students, who completed an assortment of attitude tests as well as tests of mathematical or spatial skills. All variables were controlled statistically for prior exposure to math. The hypothesis was moderately supported among males and only marginally supported among females. Moreover, numeric anxiety could not be distinguished from test anxiety. Correlational patterns suggested that anxiety was a more pervasive, significant, and monolithic factor for females than it was for males. A possible inference was that females are particularly sensitive to evaluative situations.
Sustained Attention as a Predictor of Low Academic Readiness in a Preschool Popultion
Authors: Edley Richard S. , Knopf Irwin J.
Published: November 2009

This study examined a measure of sustained attention, the Continuous Performance Task (CPT), as an early predictor of low academic readiness. One hundred and sixty kindergarteners were given the CPT, the Peabody Picture Vocabulary Test (PPVT-R), and the Metropolitan Readiness Test (MRT) in the first weeks of school. The readiness criterion was the Emory Teachers Ratings of Academic Development (TRAD), completed at mid-year. All three predictors were correlated significantly with each other and with the TRAD. High, average, and low readiness scores on the predictors significantly predicted TRAD ratings, while combining the data significantly increased forecasting efficiency. In predicting low readiness, only the CPT and MRT proved significant. The MRT was the best predictor, but the CPT was hindered by a ceiling effect and tapped a variable, sustained attention, that the MRT and TRAD do not. It was concluded that the CPT has promise as a useful, objective, and efficient preschool screener.
Stability of the WISC-R and WRAT Factor Structures for an Intellectually Retarded Sample: A 3-Year Follow-Up
Authors: Wiese Martin J. , Struer Joseph H. , Piersel Wayne C. , Schwarting F. Gene
Published: November 2009

The stability of the factor structure of the WISC-R and the WRAT is investigated over a 3-year period for a sample of educable mentally handicapped and mentally retarded students. Factor analyses indicated stable factors for intelligence and achievement across time. Similar factor structures emerged from both initial assessment and re-evaluation data. The argument that intelligence and achievement tests measure similar constructs is not supported in an intellectually retarded sample. Additional support is provided for stability of the factor structures of the WISC-R and WRAT over time.
Joint Factor Structure of the WISC-R and K-ABC for Referred School Children
Authors: Keith Timothy Z. , Novak Christine G.
Published: November 2009

The K-ABC has been the focus of considerable research and controversy, much of which has focused on understanding the constructs measured by this new test. Factor analyses of the K-ABC have found support for the test as a measure of simultaneous and sequential mental processing and achievement, but also have supported alternative interpretations, such as nonverbal reasoning, verbal memory, and verbal reasoning. The present study examined further the factorial validity of the K-ABC through joint factor analysis with the WISC-R. Of particular interest were several of the WISC-R subtests that should load differently if the K-ABC simultaneous/sequential model were valid than if an alternative interpretation were valid. Results were somewhat more supportive of a nonverbal reasoning/verbal memory interpretation of the K-ABC, but either interpretation could be supported by this research. The present study was less supportive of the K-ABC Achievement scale as a measure of school achievement. The K-ABC Achievement scale split into two factors: Reading achievement and verbal reasoning (with the WISC-R Verbal subtests). When analyzed with both the WISC-R and the WRAT, the K-ABC Reading subtests joined the WRAT tests on an achievement factor; the remaining K-ABC “achievement” tests loaded on a separate verbal reasoning factor with the WISC-R Verbal tests. Finally, the unrotated factor solutions support the notion of the K-ABC g factor as a measure of general intelligence rather than general achievement.
Content, Construct and Criterion-Related Validity of the National College of Education Test of Word Finding (TWF)
Authors: German Diane , Perney Jan
Published: November 2009

The National College of Education Test of Word Finding (TWF) measures a child's ability to name target words when presented with various pictorial and auditory stimuli. The article first deals with the issue of content validity. Evidence for construct validity then is established by showing that the TWF is unidimensional and that the instrument discriminates between children with and without word finding problems. Finally, the TWF is shown to correlate significantly with other instruments used to identify word finding problems. Overall, the results support the validity of the TWF as an assessment tool of word finding skills for children in first through sixth grades.
The Relationship between the K-ABC and the Stanford Achievement Test with Reading Disabled Children
Authors: Hooper Stephen R.
Published: November 2009

This study examined the relationship between the Kaufman Assessment Battery for Children (K-ABC) and the Stanford Achievement Test (SAT) in a sample of reading disabled children. The sample included 87 reading disabled children (48 males and 39 females), who ranged in age from approximately 8 through 12 and were enrolled in grades 2 through 6. All children were in the Average range of intellectual functioning and were at least two grade levels below their current grade placement on a word recognition screening test. The SAT was administered to all children as part of a routine group achievement testing procedure in the school district. All K-ABC testing occurred within a 2-month period after administration of the SAT. Results indicated that the K-ABC Achievement Factor significantly correlated with SAT Reading, Math, and Vocabulary, and the specific K-ABC reading and arithmetic subtests were related significantly to their respective SAT subtests. The K-ABC Cognitive Factors and their respective subtests did not relate significantly to the SAT in any particular manner. The utility of the K-ABC with specific populations is discussed, particularly as it may relate to routine assessment procedures used in the schools.
The Kaufman Assessment Battery for Children: A Validity Study with At-Risk Preschoolers
Authors: Allard AnnaMary Frank , Pfohl William
Published: November 2009

Sixty at-risk children aged 3 years, 0 months to 5 years, 11 months were assessed at two Kentucky Head Start Programs and at the University of Louisville Child Evaluation Center. At-risk status was defined by a delay on one or more areas on the Denver Developmental Screening Test. The children who met the criteria for at-risk were then administered the Kaufman Assessment Battery for Children (K-ABC). Data were analyzed by correlating subtest scores with total test scores, which resulted in an indication of internal consistency and, thus, provided partial evidence of the test's construct validity. For both the Mental Processing Scale and the Achievement Scale, evidence of construct validity was found with this sample. Findings were consistent with previous research on the K-ABC. Future areas of research are discussed.
Is the Factor Structure of the WISC-R Different for Anglo- and Mexican-American Children?
Authors: Geary David C. , Whitworth Randolph H.
Published: November 2009

A two-step procedure was employed to assess the dimensional structure of the WISC-R for samples of Anglo- and Mexican-American children. The first step involved the assessment of the goodness-of-fit of two- and three-common-factor models of the WISC-R, by using confirmatory factor-analytic procedures, for the Anglo sample. The three-common-factor solution provided the best fit for the Anglo sample data: Verbal Comprehension, Perceptual Organization, and Freedom from Distractability. Using the just-cited model, the second step employed a simultaneous multi-sample confirmatory factor analysis and evaluated the equality of factor solutions for the Anglo- and Mexican-American samples. The factor solutions, with very slight modifications, were found to be invariant across samples. Implications for the assessment of abilities that underlie the performance of Anglo- and Mexican-American children on the WISC-R were discussed.
Subgroups Based on Bender-Gestalt Error Scores
Authors: Snow Jeffrey H. , Desch Larry W.
Published: November 2009

Bender-Gestalt error scores were cluster analyzed for a large group of children and adolescents evaluated because of learning difficulties. The results indicated two subgroups; one had a relatively high percentage of Bender-Gestalt errors, while the other had a relatively low percentage of Bender-Gestalt errors. The subgroups were compared on medical, developmental and growth, social, and intelligence variables. Several significant differences were found, particularly on developmental variables. Results are discussed in terms of the clinical utility of Bender-Gestalt error scores and in relation to developmental neuropsychological theory.