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Purpose - Manufacturing organizations are under pressure to improve productivity and reduce costs through the realization of lean manufacturing. This paper approaches lean manufacturing and aims to identify and measure the intimat...
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Purpose - Manufacturing organizations are under pressure to improve productivity and reduce costs through the realization of lean manufacturing. This paper approaches lean manufacturing and aims to identify and measure the intimately associated parameters of lean manufacturing and also examines the weight of their contribution to overall lean manufacturing. Design/methodology/approach - A questionnaire survey study was performed in Indian manufacturing industries to collect data. The reliability of the survey instrument was pre-tested and an acceptable value of Cronbach's a (a reliability coefficient) was found. Three experts determined the relative weight of various parameters using analytical hierarchy process (AHP). Pearson's coefficient of correlation analysis was used to measure the strength of the relationships between various parameters of lean manufacturing. Findings - The experts found "elimination of waste" to be the most important parameter of lean manufacturing, followed by "just in time deliveries". The survey shows that most of the responding firms are in transition towards the realization of lean manufacturing. These firms believe that the factors that drive the realization of lean manufacturing are "just in time deliveries" and achieving "continuous improvement". This study also revealed that Indian manufacturing industries are still overlooking the elimination of waste, the most important parameter of lean manufacturing. Research limitations/implications - The major limitation of this paper is the sample size (n = 52). Practical implications - The present study provides guidelines to assess the status of leanness in the manufacturing industries. According to conclusions, feeble areas in the manufacturing system can be identified and a suitable course of action might be planned for the improvement. Hopefully this study will help the firm's management to identify the problems to implement an effective lean manufacturing. Originality/value - In this work, the theoretical perspective was used not only to update the original instrument, but also to study the subject from a perspective beyond that usually associated with lean manufacturing.
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Genetic parameters for scale activity score (AS) were estimated from generations 5, 6, and 7 of a randomly selected, composite population composed of Duroc, Large White, and 2 sources of Landrace (n = 2,186). At approximately 156 ...
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Genetic parameters for scale activity score (AS) were estimated from generations 5, 6, and 7 of a randomly selected, composite population composed of Duroc, Large White, and 2 sources of Landrace (n = 2,186). At approximately 156 d of age, pigs were weighed (BW) and ultrasound backfat measurements (BF1, BF2, and BF3) were done. While pigs were in the scale, an AS was assigned, which ranged from 1 (calm) to 5 (highly excited), where 58.1, 28.5, 8.9, 4.0, and 0.5% were scored as 1, 2, 3, 4, and 5, respectively. Statistical model effects were year-week of measurement, sex, covariates of age for AS and BW or BW for BF1, BF2, and BF3, and an animal direct genetic effect. A 5-trait linear mixed model was used. Estimated heritabilities were 0.23, 0.54, 0.56, 0.52, and 0.48 for AS, BW, BF1, BF2, and BF3, respectively. Estimated genetic correlations between AS and BW, AS and BF1, AS and BF2, and AS and BF3 were 0.38, 0.11, 0.12, and 0.16 respectively. Results indicated AS had a heritable genetic component and was genetically correlated with performance traits. Estimated genetic correlations between AS and backfat measurements adjusted to a common BW were negative, as was the genetic correlation of AS with BW. Therefore, selection for more docile animals would be expected to result in fatter, faster growing pigs.
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Many classic chirp signal processing algorithms may show significant performance degradation when the signal-to-noise ratio (SNR) is low. To address this problem, this paper proposes a pre-filtering method in time-domain based on ...
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Many classic chirp signal processing algorithms may show significant performance degradation when the signal-to-noise ratio (SNR) is low. To address this problem, this paper proposes a pre-filtering method in time-domain based on deep learning. Different from traditional signal filtering methods, the proposed denoising convolutional neural network (DCNN) is trained to recover the pure signal from the noisy signal as much as possible. Following denoising, we use two classic chirp signal parameter estimation algorithms to estimate the parameters of the DCNN output. The simulation results show that, compared with no DCNN processing, the parameter estimation accuracy is significantly improved. This is mainly due to the powerful pure signal extraction ability of DCNN, which can significantly improve the SNR and the accuracy of signal parameter estimation.
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Stability parameters were estimated for eight characters of Jasminum sambac (L.) Aiton cv. Single mogra under five nutrient schedules for lean season flowering during three years 2008-11. The analysis of variance showed that the n...
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Stability parameters were estimated for eight characters of Jasminum sambac (L.) Aiton cv. Single mogra under five nutrient schedules for lean season flowering during three years 2008-11. The analysis of variance showed that the nutrient schedules had significant responses towards different environment changes. Significant nutrient schedule x Environment interactions were detected for all the eight characters, ie. number of leaves at flowering, days to flower initiation, number of flower buds/plant, hundred bud weight, yield/plant, bud length, pedicel length and flower diameter. The treatment T-4 (application of 10 kg FYM/plant/year and 120:240:240 g/plant of NPK in four equal splits during February, May, September, December was found to improve lean season yield and is a stable nutrient schedule for the characters, viz. number of leaves at flowering, number of flower buds/plant and yield/plant.
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The feed restriction of pigs aims to improve the nutrient utilization of the diet, reduce carcass fat and increase lean meat. Immunocastration is a painless, reversible technique that improves animal welfare, decreases boar taint ...
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The feed restriction of pigs aims to improve the nutrient utilization of the diet, reduce carcass fat and increase lean meat. Immunocastration is a painless, reversible technique that improves animal welfare, decreases boar taint in meat, leading to lower fat deposition and increases lean meat. This study aimed at evaluating either feeding (restricted) programs (FP) and castration categories (surgically castrated x immunocastration) in terms of pig performance, carcass traits and meat quality. Castration category and FP did not influence marbling, initial pH and drip loss in loin and ham. However, immunocastrated pigs presented lighter loins and hams with lower ultimate pH, compared to the surgically castrated pigs. The FP with lower feed volume resulted in higher ultimate pH. Immunocastrated males had a higher live weight than those surgically castrated. Also, the more the feed supply decreased, the better the feed conversion. Immunocastrates had lower carcass yields, however these pigs had their backfat thickness decreased and lean meat increased in the carcass, without affecting the loin depth.
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The purpose of this study was to determine the genetic and environmental correlations between weight, lean mass and bone geometric parameters (sub-periosteal diameter, W; cross-sectional area, CSA; cortical thickness, CT; section ...
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The purpose of this study was to determine the genetic and environmental correlations between weight, lean mass and bone geometric parameters (sub-periosteal diameter, W; cross-sectional area, CSA; cortical thickness, CT; section modulus, Z; and buckling ratio, BR) of femoral neck. The sample was composed of 512 Caucasian pedigrees, including 2667 females and 1822 males. Bivariate quantitative genetic analyses were performed to evaluate the genetic (ρ G ), environmental (ρ E ) and phenotypic (ρ P ) correlations between the study traits. Univariate genetic analyses showed that the heritabilities (h 2) for bone geometric parameters were significant (P < 0.001) ranging from 0.50 to 0.60. The significant common household effects indicated the common environment shared by household members for W, CSA, CT, Z and BR (P < 0.05), but the magnitude was small compared with heritabilities. ρ E , ρ G and ρ P between bone geometric parameters and weight, lean mass were generally significant. Interestingly, lean mass showed both stronger genetic and environmental correlations with the bone geometric parameters than weight. In addition, according to the magnitude of correlation coefficients, the ρ G between body compositions and bone geometric parameters were generally stronger thanρ E (except for that between BR and body compositions). These data suggested that the geometric parameters of femoral neck are under strong genetic control. Furthermore, some common genetic and environmental factors are shared by bone geometric parameters and weight, lean mass. The results may help understand the intertwined relationships between bone metabolisms, mechanical loading and body compositions.
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High cycle-to-cycle variations (CCV) in the spark ignition (SI) engine will not only lead to incomplete combustion and even misfire, but also affect the fuel economy and even influence the drivability and conformability of a vehic...
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High cycle-to-cycle variations (CCV) in the spark ignition (SI) engine will not only lead to incomplete combustion and even misfire, but also affect the fuel economy and even influence the drivability and conformability of a vehicle, particularly at the lean-burn condition. However, the detail information about the root causes of CCV are still relatively limited, particularly the natural gas SI engine. In this paper, the impacts of the key operating and design parameters were investigated on the CCV of the high compression ratio SI natural gas engine under lean mixture condition. The results indicated that the in-cylinder pressure distribution tended to be concentrated, the number of partial burning or incomplete combustion cycles also reduced with increasing the engine speed. With increasing the load, the in-cylinder pressure distribution, peak combustion pressure and its location were tended to be concentrated. Furthermore, the number of the partial combustion or post combustion cycles declined from low-load to medium- and high-load zones. Moreover, the relationship between the peak combustion pressure and its location was almost linear with increasing the engine load. Unfortunately, with further increasing engine load, in-cylinder pressure traces started to disperse slightly. Under the low-load condition, in-cylinder pressure traces were tended to be concentrated with increasing compression ratio (CR). As CR continually increased, its influence on the in-cylinder pressure distribution decreased. In addition, the number of the partial combustion or post combustion cycles decreased with increasing CR. However, under the high-load condition, increasing the CR has slightly effects on the in-cylinder pressure distribution.
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In this study, computed tomography (CT) technology was used to measure body composition on live pigs for breeding purposes. Norwegian Landrace (L; n=3835) and Duroc (D; n=3139) boars, selection candidates to be elite boars in a br...
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In this study, computed tomography (CT) technology was used to measure body composition on live pigs for breeding purposes. Norwegian Landrace (L; n=3835) and Duroc (D; n=3139) boars, selection candidates to be elite boars in a breeding programme, were CT-scanned between August 2008 and August 2010 as part of an ongoing testing programme at Norsvin's boar test station. Genetic parameters in the growth rate of muscle (MG), carcass fat (FG), bone (BG) and non-carcass tissue (NCG), from birth to ~100 kg live weight, were calculated from CT data. Genetic correlations between growth of different body tissues scanned using CT, lean meat percentage (LMP) calculated from CT and more traditional production traits such as the average daily gain (ADG) from birth to 25 kg (ADG1), the ADG from 25 kg to 100 kg (ADG2) and the feed conversion ratio (FCR) from 25 kg to 100 kg were also estimated from data on the same boars. Genetic parameters were estimated based on multi-trait animal models using the average information-restricted maximum likelihood (AI-REML) methodology. The heritability estimates (s.e.=0.04 to 0.05) for the various traits for Landrace and Duroc were as follows: MG (0.19 and 0.43), FG (0.53 and 0.59), BG (0.37 and 0.58), NCG (0.38 and 0.50), LMP (0.50 and 0.57), ADG1 (0.25 and 0.48), ADG2 (0.41 and 0.42) and FCR (0.29 and 0.42). Genetic correlations for MG with LMP were 0.55 and 0.68, and genetic correlations between MG and ADG2 were -0.06 and 0.07 for Landrace and Duroc, respectively. LMP and ADG2 were clearly unfavourably genetically correlated (L: -0.75 and D: -0.54). These results showed the difficulty in jointly improving LMP and ADG2. ADG2 was unfavourably correlated with FG (L: 0.84 and D: 0.72), thus indicating to a large extent that selection for increased growth implies selection for fatness under an ad libitum feeding regime. Selection for MG is not expected to increase ADG2, but will yield faster growth of the desired tissues and a better carcass quality. Hence, we consider MG to be a better biological trait in selection for improved productivity and carcass quality. CT is a powerful instrument in conjunction with breeding, as it combines the high accuracy of CT data with measurements taken from the selection candidates. CT also allows the selection of new traits such as real body composition, and in particular, the actual MG on living animals.Digital Object Identifier http://dx.doi.org/10.1017/S1751731111001455
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Meat quality is of increasing economic importance to the pork industry today, which is in contrast with the more traditional focus of pig selection for lean growth. Meat quality is however determined by many factors with a complex...
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Meat quality is of increasing economic importance to the pork industry today, which is in contrast with the more traditional focus of pig selection for lean growth. Meat quality is however determined by many factors with a complex mutual relationship. In this regard, PPARGC1A is a very interesting candidate gene because it not only plays a crucial role in energy and fat metabolism but also has an important influence on the muscle fibre type composition. However, only little is known about the regulation of expression of this gene in the pig and its usefulness in pig selection. In order to get a better understanding of the regulation of PPARGC1A expression, 1 898 base pairs (bp) from the promoter region and the complete 3'UTR (3 826 bp) were sequenced and screened for mutations in 7 diverse pig breeds. Respectively 5 and 6 new mutations were discovered in these regions, of which several were in complete linkage disequilibrium with each other. None of the detected SNPs appeared to be located in any conserved part of the sequence when comparing different species. In an association analysis with intramuscular fat percentage, leaf fat weight or last rib backfat depth carried out in a Landrace-Duroc-Yorkshire commercial research population (n = 960), no associations were detected for the new SNPs from this study or for 2 previously described SNPs in exon 8 and 9. The results from this study provide essential information on the sequence of the promoter region and 3'UTR of porcine PPARGC1A, necessary for unravelling the complex regulation of expression and functioning of this gene in the pig. Although no association with meat quality and fat deposition parameters was found for the newly discovered SNPs in the regulatory regions, these need to be used in future studies to (further) assess their usefulness as new selection criteria for improving meat quality while maintaining the leanness of the carcass.
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Turbulent jet ignition (TJI) has been proven to effectively improve the burning rate and expand the lean-burn limit of gasoline engines. In this work, based on a single-cylinder engine, injection parameters in the prechamber were ...
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Turbulent jet ignition (TJI) has been proven to effectively improve the burning rate and expand the lean-burn limit of gasoline engines. In this work, based on a single-cylinder engine, injection parameters in the prechamber were investigated, combustion characteristics were studied, and pollutant emissions were optimized. Results show that the injection timing in the pre-chamber should be carefully controlled to generate a well-mixed air-fuel mixture and to avoid the diffusion of fuel from the pre-chamber to the main chamber. Therefore, the injection event should be set at the early stage of the compression stroke. Besides, excessive fuel supply in the pre-chamber should be avoided to get optimal engine performance and low pollutant emissions. The lowest indicated specific fuel consumption (ISFC) is achieved when the), is between 1.5 and 1.6, because lean combustion reduces the heat dissipation but too lean combustion causes more fuel to be burned incompletely. Moreover, to further improve the engine performance and reduce the pollutant emissions, three types of optimized pre-chamber are tested, and results show that with lower pre-chamber volume, better engine performance and lower pollutant emissions are both realized because smaller pre-chamber volume leads to less heat dissipation and less fuel burning around stoichiometric equivalence ratio in the pre-chamber. Furthermore, the prechamber with one jet hole is effective to improve the burning rate and to expand the lean-burn limit compared with the 7-hole pre-chamber, and the lean-burn limit of), is expanded to 2.2 by the optimized pre-chamber, when the minimum NOx of 0.15 g/kWh is achieved.
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