• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1933-1936
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• 2016

Heavy metals are known to disrupt important physiological processes in living cells, and have been responsible for various pathological conditions with possible contributions to cancer development. Food contamination have been identified as one of the ways humans are exposed to heavy metals. In developing countries like Nigeria, the regulatory framework for enforcing compliance with globally acceptable exposure to deleterious contaminants is poor. In the current study, thirteen samples of cured meat products of diverse origin marketed in South-west Nigeria were evaluated for lead, cadmium, chromium and nickel contents using the atomic absorption spectroscopy technique. All the samples analysed contained cadmium between 0.35 and 1.20 ppm, levels considered higher than acceptable limits in consumable products. Lead, chromium and nickel were not detected in any of the samples. As known cumulative poisons, there is the need for stringent regulatory control of these heavy metals in cured meat products imported into or produced indigenously in the country in order to minimize the risks to public health.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.8
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• pp.116-122
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• 1999

According to the stringent exhaust emission regulation, precise control of air fuel ratio is one of the most important issues on gasoline engine. Although many researches have been carried out to identify the fuel transport phenomena in a port fueled gasoline engine, complexity of fuel film behavior in the intake port makes it difficult. The fuel film behavior was investigated recently by using visualization method and these gave us qualitative understanding. The purpose of this study is to estimate of wall wetting fuel in the intake port and the inducted fuel mass was predicted by using wall wetting fuel model . The model coefficient($\alpha$,$\beta$) and fuel film mass on the port wall were determined from measured in-cylinder HC concentration using FRFID after injection off. The fuel film mass was increased, but $\alpha$(ratio of directly inducted fuel mass into cylinder from injected fuel mass) was decreased with increasing load at the same engine speed. $\beta$is nearly constant value(0.8~0.9). when injected fuel mass is varied at 1500rpm , the calculated air fuel ratio using well wetting fuel model was nearly the same as measured by UEGO.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.93-100
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• 2005

Stringent emission regulations and increasing demands on reductions of noise and vibration of common rail direct injection (CRDI) diesel engines lead to the advent of piezo-actuated injectors. Compared with solenoid-actuated injectors, piezo-actuated injectors generate greater force and give faster response time, resulting in more accurate and faster injections. The accurate and fast response of an injector can offer an opportunity to control the combustion process and pollutant formation. In this study, the mathematical model of a piezo-actuated injector is developed. An estimator of the injection rate of the piezo-actuated injector is designed based on this model. The sliding mode theory is applied to the estimator design in order to overcome model uncertainties. The injector model and the estimator are verified by the injection experiments in an injector test bench. The simulation and the experimental results show that the proposed sliding mode observer can effectively estimate the injection timing and the injection rate of the piezo-actuated injector.

• East Asian Journal of Business Economics (EAJBE)
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• v.4 no.4
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• pp.8-20
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• 2016

Banks are the engines that drive the operations in financial sector, money markets and growth of economy. With growing banking industry in India, frauds in Banks are increasing and fraudsters are becoming more sophisticated and ingenious. Shockingly, banking industry in India dubs rising fraud as "an inevitable cost of doing business." As part of study, a questionnaire-based survey was conducted in 2012-13 among 345 Bank employees "to know their perception towards bank frauds and evaluate factors that influence the degree of their compliance level." The study reveals, "there are poor employment practices and lack of effective employee training; usually over-burdened staff, weak internal control systems, and low compliance levels on the part of Bank Managers, Offices and Clerks. Although banks cannot be 100% secure against unknown threats, a certain level of preparedness can go a long way in countering fraud risk. Internal audit professionals should play an integral role in organization's fraud-fighting efforts. Some other promising steps are: educate customers about fraud prevention, make application of laws more stringent, leverage the power of data analysis technologies, follow fraud mitigation best practices, and employ multipoint scrutiny.

• Journal of Environmental Science International
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• v.17 no.12
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• pp.1413-1419
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• 2008

The Kyoto Protocol, that had been in force from February 16, 2005, requires significant reduction in $CO_2$ emissions for all anthropogenic sources containing transportation, industrial, commercial, and residential fields, etc, and automotive emission standards for air pollutants such as particulate matter (PM) and nitrogen oxides $(NO_x)$ become more and more tight for improving ambient air quality. This paper has briefly reviewed homogeneous charge compression ignition (HCCI) combustion technology offering dramatic reduction in $CO_2,\;NO_x$ and PM emissions, compared to conventional gasoline and diesel engine vehicles, in an effort of automotive industries and their related academic activities to comply with future fuel economy legislation, e.g., $CO_2$ emission standards and corporate average fuel economy (CAFE) in the respective European Union (EU) and United States of America (USA), and to meet very stringent future automotive emission standards, e.g., Tier 2 program in USA and EURO V in EU. In addition, major challenges to the widespread use of HCCI engines in road applications are discussed in aspects of new catalytic emissions controls to remove high CO and unburned hydrocarbons from such engine-equipped vehicles.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.8-15
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• 2014

In order to satisfy stringent future emission regulation in diesel engines, systematic approaches to mitigate the harmful exhaust emissions were developed, such as engine hardware, fuel injection equipment, engine control, and after-treatment system. In this study, to improve the nano-particle and NOx emissions from a state-of-the-arts diesel engine, effect of various EGR and fuel injection pressure with combustion analysis were evaluated. Size-resolved nano-particle and NOx emissions showed trade-off characteristics with various EGR rate and increment of fuel injection pressure.

• International Journal of Automotive Technology
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• v.6 no.2
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• pp.95-105
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• 2005

Diesel engines have low specific fuel consumption, but high particulate emissions, mainly soot. Diesel soot is suspected to have significant effects on the health of living beings and might also affect global warming. Hence stringent measures have been put in place in a number of countries and will be even stronger in the near future. Diesel engines require either advanced integrated exhaust after treatment systems or modified engine models to meet the statutory norms. Experimental analysis to study the emission characteristics is a time consuming affair. In such situations, the real picture of engine control can be obtained by the modeling of trend prediction. In this article, an effort has been made to predict emissions smoke and NO$_{x}$ using cylinder combustion derived parameters and diesel particulate filter data, with artificial neural network techniques in MATLAB environment. The model is based on three layer neural network with a back propagation learning algorithm. The training and test data of emissions were collected from experimental set up in the laboratory for different loads. The network is trained to predict the values of emission with training values. Regression analysis between test and predicted value from neural network shows least error. This approach helps in the reduction of the experimentation required to determine the smoke and NO$_{x}$ for the catalyst coated filters.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.3
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• pp.263-271
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• 2010

A reaction wheel is commonly used, as an important actuator, to control the attitude of a satellite. Operation of the reaction wheel plays a role of an excitation source to loading equipment inside the satellite. As requirements for environmental vibration to manifest the performance of precision equipment are getting more stringent, the research for analysis or reduction of unwanted action force in high frequency range when operating the reaction wheel is necessary. In this paper, the procedure to extract input forces and damping of a rotor system of reaction wheel is suggested. The analysis for measured action forces of reaction wheel is accomplished and important higher harmonics of action forces are determined. The input forces and damping of the rotor system are, then, extracted by curve-fitting and a particular solution for input force.

• Environmental Engineering Research
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• v.23 no.4
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• pp.397-405
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• 2018

As regulations governing the control of volatile organic compounds (VOCs) have become increasingly stringent in China, regenerative thermal oxidizers (RTOs) have been more frequently applied in medium- and high-concentration VOCs treatments. However, due to the lack of existing RTO-related research, experience remains a dominant factor for industrial application. This paper thus aimed to establish a model for industrial RTOs, using a transient simulation method and thermal equilibrium model to simulate the internal velocities and temperature distributions of an RTO across multiple cycles. A comparison showed an error of less than 5% between most correlating simulated and experimental measurement points, verifying that the simulation method was accurate. After verification, the velocity and temperature fields inside the RTO were simulated to study the uniformity of temperature and velocity within the packed beds: both fields displayed high uniformity after gas flowed through the honeycomb regenerator. The effects of air volume, VOCs concentrations, and valve switching times on the oxidation chamber temperature, RTO outlet temperature, and thermal efficiency (as well as their averages) were studied. The VOCs removal rate in this study was constantly above 98%, and the average thermal efficiency reached 90%.

• Journal of ILASS-Korea
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• v.25 no.4
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• pp.188-195
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• 2020

To meet stringent emission regulations of automotive engines, fuel injection control techniques have advanced based on reliable and fast computing prediction models. This study aims to develop a reliable lightweight prediction model of fuel injection rates using a small number of input parameters and based on simple fluid dynamic theories. The prediction model uses the geometry of the injector nozzle, needle motion data, injection conditions and the fuel properties. A commercial diesel injector and US No. 2 diesel were used as the test injector and fuel, respectively. The needle motion data were measured using X-ray phase-contrast imaging technique under various fuel injection pressures and injection pulse durations. The actual injector rate profiles were measured using an injection rate meter for the validation of the model prediction results. In the case of long injection durations with the steady-state operation, the model prediction results showed over 99 % consistency with the measurement results. However, in the case of short injection cases with the transient operation, the prediction model overestimated the injection rate that needs to be further improved.