The goal of zero defects is pursued by many manufacturing and service companies. In this regard, statistical tools are being used for defect reduction leading to productivity improvement. In this ...work, seven traditional QC tools (flow chart, check sheet, histogram, Pareto chart, cause, and effect diagram, scatter diagram and control chart) have been developed and implemented in an automobile company to assess and improve the defect reduction level in the assembly line. Chassis and trim lined were selected for data collection to assess and improve the defect level for productivity improvement. It was found from the results that after the successful implementation of the QC tools, the defect level reduced by 90% (from 132 to 13 defects) at the chassis line. Similarly, the defect level was reduced by 80% (from 157 to 28 defects) at the trim line. The automobile company implemented only a few of the seven QC tools in their assembly line. It is suggested that the company may need to manage a mechanism for the implementation of all seven QC tools in every section of the company.
Exhaust emissions of a diesel engine are considered to be a substantial source of environmental pollution. Diesel engines are mainly used in vehicles and power generation. The usage of diesel engines ...is unavoidable as they give more power and performance, but at the same time, higher usage of diesel engines leads to increased air pollution, sound pollution, and emissions to the environment. Therefore, various attempts have been made to control the harmful emissions of engines. For this reason, different devices have been made such as catalytic convertors to overcome emission problems and purify the harmful gases. In order to meet these ends, a new system was designed that would contribute to controlling the air pollution of the engines. The system is also known as an aqua silencer, and its design is somehow different but still can be used as a silencer. The newly designed emission controller was installed in a test-bed diesel engine and a total of twenty experiments were conducted with and without the new emission controller at constant speed and at constant load. During these experiments, exhaust gases were analyzed with flue gas analyzers measuring CO2, CO, NO2, NO, and PM. The study concluded that the contaminants of diesel engine exhaust gases were) controlled by the developed emission controller.
Increasing environmental concerns forced us to look for cheaper, reliable and secure sources of energy. Fossil fuels like oil, coal, and natural gas are having limited supplies and are depleting ...fast. Both energy security and environmental concerns have resulted in inclination towards renewable energy sources. Biodiesel does not contain petroleum, but it can be blended with petro-diesel in various mix levels. This research investigated biodiesel produced by the use of cheap waste cooking oil, collected from the local market of Nawabshah, Pakistan. The collected waste oil was converted into biodiesel by trans-esterification process at PCSIR Laboratory, Karachi. The fuel samples were tested in a diesel engine test bed unit at the Thermodynamics Laboratory of Quaid-e-Awam University. Biodiesel blends were compared with the conventional diesel fuel. The comparative analysis of the performance parameters concluded that brake specific fuel consumption of B30 (biodiesel 30%+diesel 70%) mix was 6.9% higher than that of 100% diesel. The brake thermal efficiency of B30 decreased about 4.75% in comparison with conventional diesel.
ISO 9001:2015 is known as the highest quality management standard, enhancing customer and company satisfaction. While the manufacturing industry is playing a vital role in Pakistan’s GDP, the ...implementation of ISO 9001:2015 is not widespread. This study aims to examine the factors that hinder the implementation of ISO 9001:2015 in Pakistan’s manufacturing industry and recommend suggestions to overcome them. An in-depth literature review identified 32 general factors that hinder the implementation of ISO 9001:2015. A structured questionnaire was designed and distributed to 135 respondents to examine the factors hindering the implementation of ISO 9001:2015 in Pakistan’s manufacturing industry. The gathered data were analyzed using the average index formula, and 8 significant factors were identified. These factors were used in the design of a semi-structured questionnaire distributed among high qualified and experienced respondents working in top managerial posts of manufacturing industries in Pakistan. The collected data were analyzed using content analysis. The findings can be helpful in the determination of recommendations regarding the implementation of ISO 9001:2015 in the manufacturing industries of Pakistan.
As the demand for concrete rises, the concrete materials demand increases. Aggregates occupy 75% of concrete. A vast amount of aggregates is utilized in concrete while aggregate natural resources are ...reducing. To overcome this problem, River Indus sand (RIS) and recycled concrete aggregate (RCA) were utilized as fine and coarse aggregate respectively. The aim of this experimental investigation is to evaluate the workability, and compressive and tensile strength of concrete utilizing RIS and RCA. Concrete samples of 1:2:4 proportions were cast, water cured for 7, 14, 21 and 28 days, and tested for compressive and tensile strength. The outcomes demonstrate that concrete possessed less workability when RIS and RCA were utilized. It was predicted that compressive strength of concrete would reduce up to 1.5% when 50% RIS and 50% RCA were utilized in concrete and 11.5% when natural aggregate was fully replaced by RIS and RCA, whereas the tensile strength decreased up to 1.60% when 50% by 12% respectively.
Composite materials have been used to resolve industrial problems. Considerable attention from the industrial side started in the 1960s with the introduction of polymer-based composite materials. ...Their advantages such as low weight (density), resistance to corrosion, high strength and low maintenance cost made composite materials an attractive substitute to conventional materials. A new composite material was developed with 10% natural fiber at 0o, 90o and 0/90o orientations resulting in ample improvements in the mechanical properties as compared to previous studies. The sample at 0/90o orientation gives the best results with tensile, tensile strength, tensile elongation and Young's Modulus values of 2458.19N, 4594.5MPA, 4.7% and 23.0 respectively
Multivariate statistical techniques, cluster analysis (CA) and principal component analysis (PCA) were applied to the data on water quality of Manchar Lake (Pakistan), generated during 2005–06, with ...monitoring at five different sites for 36 parameters. This study evaluated and interpreted complex water quality data sets and apportioned of pollution sources to get better information about water quality and to design a monitoring network. The chemical correlations were observed by PCA, which were used to classify the samples by CA, based on the PCA scores. Three significant sampling locations—(sites 1 and 2), (site 4) and (sites 3 and 5)—were detected on the basis of similarity of their water quality. The results revealed that the major causes of water quality deterioration were related to inflow of effluent from industrial, domestic, agricultural and saline seeps into the lake at site 1 and also resulting from people living in boats and fishing at sites 2 and 3.
The aim of present study was to develop a database of arsenic (As) in lake water, ground water, sediment, soil, vegetables, grain crops and fish to evaluate the potential human health risks posed by ...higher level of As, in south east part of Sindh, Pakistan during 2005–2007. The total concentration of As in various samples under study was determined by electrothermal atomic absorption spectrophotometry (ETAAS). The reliability and accuracy of technique was checked by different certified reference materials. The concentration of As in lake and ground water samples exceeded the WHO guideline values. The concentration of As in lake sediment and agricultural soil samples ranged between 11.3–55.8 and 8.7–46.2
mg/kg while acid soluble As (acetic acid 0.11
mol/L) was observed in the range of 1.48–3.54 and 0.34–3.78
mg/kg, respectively. It was observed that the leafy vegetables (spinach, coriander and peppermint) contain higher As levels (0.90–1.20
mg/kg) as compared to ground vegetables (0.048–0.25) and grain crops (0.248–0.367
mg/kg) on dried weight basis. The estimated daily intake of total As in the diet was 9.7–12.2
μg/kg body weight/day.
The objective of this study was to evaluate the association between trace and toxic elements zinc (Zn), cadmium (Cd), nickel (Ni) and lead (Pb) in biological samples (scalp hair, blood and urine) of ...smoker and nonsmoker hypertensive patients (n=457), residents of Hyderabad, Pakistan. For the purpose of comparison, the biological samples of age-matched healthy controls were selected as referents. The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference materials and by the conventional wet acid digestion method on the same certified reference materials and real samples. The recovery of all the studied elements was found to be in the range of 97.8-99.3% in certified reference materials. The results of this study showed that the mean values of Cd, Ni and Pb were significantly higher in scalp hair, blood and urine samples of both smoker and nonsmoker patients than in referents (P<0.001), whereas the concentration of Zn was lower in the scalp hair and blood, but higher in the urine samples of hypertensive patients. The deficiency of Zn and the high exposure of toxic metals as a result of tobacco smoking may be synergistic with risk factors associated with hypertension.
The concentrations of heavy metals (HMs) in plants served to indicate the metal contamination status of the site, and also revealed the abilities of various plant species to take up and accumulate ...them from the soil dressed with sewage sludge. A study to comprehend the mobility and transport of HMs from soil and soil amended with untreated sewage sludge to different newly breaded varieties of wheat (Anmol, TJ-83, Abadgar and Mehran-89) in Pakistan. A pot-culture experiment was conducted to study the transfer of HMs to wheat grains, grown in soil (control) and soil amended with sewage sludge (test samples). The total and ethylenediaminetetraaceticacid (EDTA)-extractable HMs in agricultural soil and soil amended with domestic sewage sludge (SDWS) and wheat grains were analysed by flame atomic absorption spectrometer/electrothermal atomic absorption spectrometer, prior to microwave-assisted wet acid digestion method. The edible part of wheat plants (grains) from test samples presented high concentration of all HMs understudy (mg
kg
−1). Significant correlations were found between metals in exchangeable fractions of soil and SDWS, with total metals in control and test samples of wheat grains.
The bio-concentration factors of all HMs were high in grains of two wheat varieties, TJ-83 and Mehran-89, as compared to other varieties, Anmol and Abadgar grown in the same agricultural plots.
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