• CELLMED
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• v.6 no.1
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• pp.3.1-3.4
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• 2016

Consumption of herbal products from the medicinal plants contaminated with heavy metals can cause serious consequences on human health. This is a major concern for traditional and herbal medicine. The present study was carried out to analyze and quantify the levels of six potentially toxic heavy metals namely arsenic, lead, cadmium, mercury, chromium and nickel in ten important Indian medicinal herbs. The air dried raw herbs were processed by microwave assisted wet digestion and analyzed by using atomic absorption spectrophotometer equipped with graphite tube atomizer. Except the chromium content in three plants, all the levels of six heavy metals analyzed were found to be quite below the permissible limits in all the ten raw medicinal herbs analyzed. The present work implies that, regular and systematic screening of raw medicinal herbs is necessary to check the levels of the heavy metal contaminants before using them for consumption or preparation of herbal formulations so that the possible contamination cannot cumulate up to the finished products.

• Resources Recycling
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• v.10 no.4
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• pp.10-17
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• 2001

The present work investigates the possible use of fly ash for the removal of heavy metal ions from aqueous solutions. Batch experiments were conducted and the influences of metal concentration, pH, and fly ash concentration were investigated. Heavy metals used in these studies were lead and zinc. Adsorption studies were done over a range of pH values (3~10) at $25^{\circ}C$ and heavy metal concentrations of 10~400 mg/L using fly ash concentrations of 10 and 20 g/L. Experiments were also conducted without fly ash to determine the extent of heavy metal removal by precipitation. Kinetic and equilibrium experiments were performed and adsorption data were correlated with both Langmuir and Freundlich adsorption models. The results of these studies indicate that 리y ash can be used as an adsorbent for heavy metals in the aqueous solutions, yet the degree of removal depends on the pH.

• Advances in materials Research
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• v.6 no.1
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• pp.79-91
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• 2017

In the present work, a design of experiment (DOE) technique using Taguchi method, has been applied to optimize the properties of ODS tungsten heavy alloys(WHAs). In this work Taguchi method involves nine experiments groups for four processing parameters (compaction pressure, sintering temperature, binding material type, and oxide type) with three levels was implemented. The signal-to-noise (S/N) ratio and analysis of variance (ANOVA) were employed to obtain the optimal process parameter levels and to analyze the effect of these parameters on density, electrical conductivity, hardness and compressive strength values. The results showed that all the chosen factors have significant effects on all properties of ODS tungsten heavy alloys samples. The density, electrical conductivity and hardness increases with the increase in sintering temperature. The analysis of the verification experiments for the physical properties (density and Electrical conductivity) has shown that Taguchi parameter design can successfully verify the optimal parameters, where the difference between the predicted and the verified values of relative density and electrical conductivity is about 1.01% and 1.15% respectively.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.2
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• pp.88-94
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• 2013

The primary objective of the current work is to obviously analyze regarding effects of trim conditions of a ship on resistance performance using model test and CFD. Model tests at a towing tank are conducted to investigate resistance for trim conditions at the given same displacement. Measured resistance shows small but distinct differences according to trim conditions. However, these differences are difficult to be clarified by measured physical quantities and wave pattern analysis from model tests. CFD is employed for the assessment of resistance performance according to trim conditions. The flow computation is conducted considering free surface and dynamic trim using a commercial CFD code (STAR-CCM+). The initiative of the present work is to systematically demonstrate pressure resistance acting on each region of divided finite zones of ship surface along the length and draught direction of surface when pressure distribution on the ship is interpreted. Also, a standard to assess the pressure resistance applied on the divided regions of a ship is established.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.67-73
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• 2016

According to industrial accident analysis of the Ministry of Employment and Labor in 2013, 38 workers were injured by fall accidents on average per day, and one worker died on average per day among them. In various industries such as heavy and construction industry, the full body harness is commonly used to prevent the fall accident. In developing full body harness, the designer considered only the workers' safety, without taking into account comfort and workability. The survey was conducted so as to search the problems of full body harness currently used by workers in heavy and construction industry. The survey questionnaire was given to 565 workers wearing full body harness in heavy and construction industry. The results of study showed that the development of new full body harness considering body size of korean was needed. The impotent factors for developing of new full body harness were the size and the weight of the full body harness. The full body harness taking into account body size was judged to contribute to more comfortable work, work efficiency and safety. The result of this study can be utilized as useful data in the development of new full body harness considering the body size of korean workers.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.130-131
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• 2016

Although many metals contaminated sediment from coastal area contain both anionic and cationic heavy metals, the current remediation technologies are not effective for stabilize heavy metals of both anionic and cationic elements from contaminated coastal region. the present work investigated the efficiency and mechanism of immobilization of Fe, Zn, Cr, Cu, Pb and Cd metal solutions in modified zeolite based biostimulant ball. Biostimulant ball containing acetate, nitrate and sulphate which are enhance the activity of marine microorganisms and it can act as electron donors and electron acceptors. Modified zeolite and chelating agent is greatly enhance the metal stabilization due to increased immobility of the analysed metals. The XRD, FT-IR and SEM of modified zeolite which cheating agents containing heavy metals were investigated. The results indicated that heavy metals could be effectively immobilized in modified zeolite and chelating agents in BSB added sediment. The immobilization of heavy metals in modified zeolite and chelating agents along with BSB could be due to stabilize of heavy metal cations. Immobilization of heavy metals using BSB with modified zeolite and chelating agent has lower cost effect and enhance the sediment quality.

• Research in Community and Public Health Nursing
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• v.7 no.2
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• pp.400-409
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• 1996

To investigate industrial fatigue and low back pain, the questionaire survey for subjective symptoms of fatigue and low back pain was carried out among 591 male workers aged 20-55 employed in an automobile industry in Korea. Workers participated to this study were divided into low back pain group(LBP) and control group, according to the self-reports by written questionaires. The subjective sysptoms of fatigue comprised three groups of 10 items each, representing dullness and sleepiness(level of cerebral activation), difficulty in concentration(level of motivation) and bodily projection of fatigue. The resultant data were processed for $\chi^2-test$, t-test and a pearson's correlation coefficient to confirm the relationships. The results were as follows: 1. 30 items of fatigue subjective symptoms exeptone item, 'lack in perseverance', were directly associated with low back pain. 2. The percentage of fatigue complaint were sig nificantly higher in LBP group. 3. Of the 30 items of fatigue subjective symptoms, the highest percentage was accounted for 'eye strain'(27.9%), followed by 'whole body feels tired' and 'legs feel heavy'(22.9%), 'feel like lying'(21.4%), 'feel a pain in the low back'(18.7%), 'feel drowsy'(16.4%) and 'feel stiffness in the neck or the shoulders'(16.2%) in the order of sequence. 4. The average weighted score for the first group of fatigue items(dullness and sleepiness) was the largest among three groups and was followed by the second group(difficulty in concentration) and the third group(bodily projection of fatigue) in the order of sequence, suggesting the heavier shift work stress of the workers. 5. In the groups of the aged 30-40, work duration of 5-7yrs, heavy work amount and irregular work speed, significant high fatigue complaints were revealed in terms of eye strain, whole body feels tired, legs feel heavy, feel like lying, feel a pain in the low back and feel stiffness in the neck or the shoulders. 6. A significant negative correlations were shown between age, work duration and eleven subjective symptoms while positive reciprocal correlations were shown between eleven items with one another.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.397-400
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• 2002

The purpose of this study is to analyze current status and propose improvement scheme of safety management on the heavy construction equipment operation. The research method invloves interview and questionnaire survey for the analysis of practical use status of heavy construction equipment. The results of this study are as fallows: 1) The problem of safety management status on heavy construction equipment operation is surveyed not wearing safety helmet, not keeping work regulations, and not preparing the work before start. 2) Proposed improvement scheme of safety management on heavy construction equipment operation includes strengthening 5 minutes safety education before start, strengthening safety action against falling materials, and strengthening enough preparation before start.

• Journal of Environmental Science International
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• v.6 no.1
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• pp.33-44
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• 1997

In investigating heavy metal contents at specific areas, the method of selecting sampling points is Important A general method is, according to the law , random sampling of zigzag-form in the selected field. In this work, we studied whether the measured values obtained from a certain method of selecting sampling points is a representative of heavy metal contents in the selected field or not. The selected field for this study is located on the lower Yangsan-river: Gasan-li, Mulgum-myon, Yangsan-gun, KyoungNam, 1 km away from the mi, h stream of Nakdong river. The heavy metals investigated were Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn. The inductively coupled plasma(ICPI atomic emission spectrometer was used to measure these metals quantitatively. The number of total sampling points were 24. We compared the total mean values with the mean obtained from various methods of selecting sampling points.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.431-434
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• 2003

Environmental pollution problems due to the wastes from various industrial facilities and activities have become a serious issue. The specific problem associated with heavy metals in the environment is their accumulation in the food chain and their persistence in nature. Present work investigates the possible uses of by-products for the removal of heavy metal ions. Heavy metals used in these studies were cadmium, lead and copper. Experiments were conducted with by-products such as oyster shell and fly ash to evaluate their sorption characteristics. The results of the study indicate that oyster shell can be properly used as an adsorbent for heavy metals because of its outstanding removal rate.