• Computers and Concrete
• /
• 제21권4호
• /
• pp.377-384
• /
• 2018

The accelerated increase of the population growth rate in the world and the current lifestyle based on consumerism considerably increased the amount of waste generated by the human activity. Specifically, e-plastic waste causes significant damage to the environment because of its difficult degradation process. This paper aims to establish the feasibility of using e-plastic waste in concrete as a partial replacement of coarse mineral aggregate. Considering a control mix without e-plastic waste designed for a compressive strength of 21 MPa, tests on concrete mixes with 40, 50 and 60% of e-plastic waste aggregate to determine the fresh and hardened properties were carried out. A reduction in the compressive strength as the percentage of e-plastic waste increases was observed, the maximum reduction being 44% with respect to the control mix. In addition, a significant reduction as much as 22% in the density of the concrete mixes with e-plastic waste was recorded, which means that lighter elements can be produced with this type of concrete. Two new equations based on regression analysis of the experimental data from this study were proposed. These equations estimate the reduction in the compressive strength of concrete mixes with e-plastic waste aggregate at 14 and 28 days. A cost analysis and a practical alternative to introduce this waste material into the market are also presented.

• Imaging Science in Dentistry
• /
• 제36권2호
• /
• pp.73-79
• /
• 2006

Purpose : To describe the MRI findings of the antero-superior attachment of the disc in patients with internal derangement. Materials and Methods : One hundred fifty-six MR images from 40 normal subjects and 55 abnormal subjects were classified into three study groups of normal, anterior disc displacement with reduction and anterior disc displacement without reduction. On both closed- and open-mouth proton density sagittal images, the depiction of the antero-superior attachment of the disc and its demarcation from the disc were evaluated in three cuts of lateral, central and medial one thirds of the condyle. Results : The depiction of antero-superior attachment was more frequent by the order of normal, anterior disc displacement with reduction and anterior disc displacement without reduction groups, and the significant differences were found on lateral cut of the closed images and lateral and central cuts of the open images. In study for the demarcation between the antero-superior attachment and the disc the lateral cut of the closed images and all three cuts of the open images showed significant differences. Conclusion : Open images are useful to show the difference in depiction of the antero-superior attachment of the disc among the TMJ groups.

• 한방재활의학과학회지
• /
• 제19권2호
• /
• pp.275-287
• /
• 2009

Objectives : In order to observe clinical effects, carboxytherapy and electroacupuncture, we analyzed relation effect and patients' character, and researched correlation among reduction of BFM(Body Fat Mass), WHR(Waist-Hip Ratio) and AC(Arm Circumference). Methods : Among outpatients who had admitted to department of oriental rehabilitation medicine, Dae-Jeon oriental medicine hospital, Dae-Jeon university from January to September, 2008 for obesity treatment and abdominal fat, 44 subjects were chosen and carboxytherapy and electroacupuncture were practiced concurrently. Results : 1. The group under the concurrent practice of carboxytherapy and electroacupuncture showed significant decrease in BFM, BFR(Body Fat Rate), WHR and AC. 2. The group under the concurrent practice of carboxytherapy and electroacupuncture did not show statistical significance but showed decrease in BFM, WHR. The degree of decrease was proportional to that of obesity. 3. As AC decreased, BFM, WHR reduction tended to increase as well in the group under the concurrent practice of carboxytherapy and electroacupuncture. 4. Compared to the group under the sole practice of electroacupuncture, the group under the concurrent practice of carboxytherapy and electroacupuncture showed less change in BFM reduction and greater change in WHR reduction. Conclusions : From the above results, the concurrent practice of carboxytherapy and electroacupuncture had an effect on obesity and reducing abdominal fat, but did not show statistically significant decrease compare to the sole practice of electroacupuncture.

• 한국물환경학회지
• /
• 제31권4호
• /
• pp.407-417
• /
• 2015

Soil loss is one of the significant disasters which have threatened human community and ecosystem. Particularly, Korea has high vulnerability of soil loss because rainfall is concentrated during summer and mountainous regions take more than 70% of total land resources. Accordingly, the sediment control management plan are required to prevent the loss of soil resources and to improve water quality in the receiving waterbodies. In this regard, the objectives of this study are 1) to quantify the effect of the Vegetative Filter Strip (VFS) on sediment runoff reduction and 2) to analyze the relationship of rainfall intensity and sediment runoff. For this, SATEEC and VFSMOD were used to estimate sediment runoff according to rainfall intensity and to quantify the effect of VFS on sediment runoff reduction, respectively. In this study, the VFS has higher impact on sediment reduction for lower maximum rainfall intensity, which means that the maximum rainfall intensity is one of significant factors to control sediment runoff. Also, the sediment with VFS considered was highly correlated with maximum rainfall intensity. For these results, this study will contribute to extend the applicability of VFS in establishing eco-friendly sediment control plans.

• 산업기술연구
• /
• 제27권B호
• /
• pp.229-233
• /
• 2007

This research investigated the way of generating the flowing of water in case of artificial fluctuation of river width by the unidimensional numerical analysis in order to reconstruct vertical and expanse features of flowing, and the problem of existing numerical analysis in accordance with local enlargement and reduction of river through hydraulic model experiments with results of numerical analysis. The result revealed that when the local section change in the same river is exist, it showed 0.93m in the case of no change of local section in the hydraulic model experiments and numerical analysis, however, it presented 1.645m on the occasion of local section changes in the hydraulic model experiments and numerical analysis. In other words, there was a significant difference in the existing numerical analysis, when there was a local section change. As a result of the experimental section for the enlargement and reduction of local river width, due to the sensitive change for fluctuation of flood discharge, there was a significant difference between numerical analysis and hydraulic model experiments. In addition, the result of comparison between the enlargement and reduction of local river width confirmed that the result of numerical analysis with hydraulic model experiments showed larger generation of deviation in case of enlargement of section than in case of reduction of section.

• Nuclear Engineering and Technology
• /
• 제47권7호
• /
• pp.849-858
• /
• 2015

This study set the pyroprocess facility at an engineering scale as a cost object, and presented the cost consumed during the unit processes of the pyroprocess. For the cost calculation, the activity based costing (ABC) method was used instead of the engineering cost estimation method, which calculates the cost based on the conceptual design of the pyroprocess facility. The calculation results demonstrate that the pyroprocess facility's unit process cost is $194/kgHM for pretreatment, $298/kgHM for electrochemical reduction, $226/kgHM for electrorefining, and $299/kgHM for electrowinning. An analysis demonstrated that the share of each unit process cost among the total pyroprocess cost is as follows: 19% for pretreatment, 29% for electrochemical reduction, 22% for electrorefining, and 30% for electrowinning. The total unit cost of the pyroprocess was calculated at $1,017/kgHM. In the end, electrochemical reduction and the electrowinning process took up most of the cost, and the individual costs for these two processes was found to be similar. This is because significant raw material cost is required for the electrochemical reduction process, which uses platinum as an anode electrode. In addition, significant raw material costs are required, such as for $Li_3PO_4$, which is used a lot during the salt purification process.

• 소성∙가공
• /
• 제18권5호
• /
• pp.410-415
• /
• 2009

Experimental and numerical studies were performed to examine the effect of material temperature and reduction ratio on friction coefficient during hot flat rolling. We carried out a single pass pilot hot flat rolling test at the temperatures range of $900{\sim}1200^{\circ}C$ and measured the spread of deformed material while reduction ratio varied from 20% to 40%. Materials used in this study were a high carbon steel and two alloy steels. The dimension of specimen used in hot rolling experiment was $50mm{\times}50mm{\times}300mm$. We performed a series of finite element simulation of the hot rolling process to compute the friction coefficient change in terms of steel grade and reduction ratio. Results showed that temperature dependency of friction coefficient is not noteworthy but the effect of reduction ratio on friction coefficient is quite large. For high carbon steel, friction coefficient at reduction ratio of 30% is lower than that at that of 20%. Meanwhile friction coefficient at reduction ratio of 40% was one and half times large compared with that at that of 20%. The effect of steel grade on friction coefficient was significant when reduction ration was large, e.g., 40%.

• 대한의용생체공학회:의공학회지
• /
• 제28권1호
• /
• pp.46-54
• /
• 2007

Objective: The first aim of this study is to determine the effects of acupuncture on the autonomic nervous system (ANS) via Heart Rate (HR) and Pupil Size (PS), and to compare the effects of acupuncture on the subjects' ANS when they are in a sitting position with the effects when they are in a supine position. Methods: Ten healthy male subjects were randomized to receive either verum acupuncture stimulation in a sitting position (SitV), verum acupuncture stimulation in a supine position (SupV), sham acupuncture stimulation in a sitting position (SitS), and sham acupuncture stimulation in a supine position (SupS). Acupuncture stimulation was applied to Neguan point (PC6) on the forearm. The subject's electrocardiogram (ECG) and pupil size were recorded continuously from 5 min before stimulation to 12 min after stimulation. Results: Verum and sham acupuncture stimulation were found to have reduced heart rate (p<0.01) and to have increased pupil size (p<0.01) in all the subjects. But when the reduction in HR and the increment in PS after verum acupuncture stimulation (both sitting and supine position) were compared with those after sham acupuncture stimulation, it was found that the reduction in HR (74.48 and 73.47 bpm, p<0.063) and the increment of PS (7.32 and, 6.10 mm, p<0.001) after verum acupuncture stimulation were greater than those after sham acupuncture stimulation, and that the corresponding values were statistically significant. In addition, at the baseline, it was found that the subjects had a larger PS and a faster HR in a sitting position than when they did so in a supine position. And then the reduction and increment ratio in the subject's HR and PS when they underwent acupuncture stimulation in a sitting position was significantly different from the reduction and increment in their HR and PS when they underwent the procedure in a supine position-i.e., the reduction ratio in HR was greater when they underwent the procedure in a sitting position, and such reduction ratio was statistically significant (p<0.05). As for the increment in PS, it was greater when the subjects underwent the procedure in a supine position, and such increment was significant (p<0.05). Conclusion: Manual acupuncture stimulation on Neguan point (PC6) has more significant influence on the autonomic nervous system rather than sham acupuncture (tactile stimulation). And the position-induced different states of ANS have different influence on the acupuncture effect.

• Journal of Nutrition and Health
• /
• 제40권7호
• /
• pp.630-638
• /
• 2007

This study was performed to examine the combined effects of L-carnitine and isoflavone supplementation on weight reduction and body fat distribution in overweight women. Overweight/obese women (body mass index > $23kg/m^2$) who were not diagnosed any type of diseases were included in this study and sixty subjects ($41.1{\pm}1.5$ years, $25.9{\pm}0.3kg/m^2)$ were randomly assigned to a placebo (n=30) or a supplement group (n=30, L-carnitine 300 mg+isoflavone 40 mg/day). We measured anthropometric parameters, abdominal fat distribution by computerizd tomography and blood components before and after the 12 week intervention period. After the 12 weeks of supplementation, subjects in L-carnitine and isoflavone supplement group showed a significant reduction of body weight (p < 0.001), body fat % (p < 0.05), and waist to hip ratio (p < 0.01) whereas placebo group did not show any changes. In a CT-scanned results, total fat area at L4 level was significantly reduced by 8.1% (p < 0.01) with the reduction of visceral fat area (-11.1%, p < 0.001) and subcutaneous fat area (-7.0%, p < 0.05) in the supplement group. The supplementation of L-carnitine and isoflavone showed the significant improvement of HDL-C (p < 0.01) and apoB (p < 0.05) concentrations, however, change values in those markers were not significant compared with those of the placebo group. In addition, a significant increase of adiponectin level (p<0.001) was observed in the supplement group after the intervention. The result of present study demonstrated that supplementation of 300 mg L-carnitine and 40 mg isoflavone per day fur 12 weeks can give beneficial effects on weight reduction and visceral fat accumulation. These potential antiobesity supplement can produce more favorable effects when combined with lifestyle modification.

• Journal of Periodontal and Implant Science
• /
• 제36권3호
• /
• pp.693-703
• /
• 2006

The purpose of this study was to evaluate the efficacy of the Sonicare $Elite^{(R)}$ power toothbrush in plaque removal and reduction of gingivitis from hard-to-reach sites of the moderate periodontitis compared to regular manual toothbrush in 12 week follow-up. 82 subjects with incipient to moderate periodontitis were randomly assigned to use either the manual or sonic brush, instructed in its use, and asked to brush 2 times a day for 2 minutes. Plaque scores were taken at baseline, 1, 4, 12 weeks using Silness & $L\ddot{o}e$ plaque index and gingival inflammation was assessed by the $L\ddot{o}e$ & Silness gingival index. The results were as follows. 1. The Sonicare $Elite^{(R)}$ power toothbrush showed a significant reduction(p<0.0001) of the plaque(Silness & $L\ddot{o}e$) and gingival inflammation(Loe & Silness). 2. The Sonicare $Elite^{(R)}$ power toothbrush showed a significant better reduction of plaque and gingivitis(p<0.05) than the manual toothbrush after 1, 4, and 12 weeks. 3. The Sonicare $Elite^{(R)}$ power toothbrush demonstrated a significant reduction(p<0.0001) of the plaque in interproximal sites(p<0.0001), buccal sites(p<0.0001) and the lingual sites(p=0.00l8) of the teeth. 4. The Sonicare $Elite^{(R)}$ power toothbrush demonstrated a significant reduction(p<0.0001) of the gingival inflammation in the interproximal sites(p<0.0001), the buccal sites(p<0.0001) and the lingual sites(p<0.0001) of the teeth. The results of this study support the findings that Sonicare $Elite^{(R)}$ power toothbrush has a great potential to remove the plaque and resolve the gingival inflammation during the period of 12 week.