• Korean Journal of Digital Imaging in Medicine
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• v.12 no.2
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• pp.97-101
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• 2010

This experimental study is carried out one of the General Hospital in Kyungbok providence. Abdomen Phantom being located Anterior-posterior(AP) position on portable bed, and the portable X-ray generating device was placed the phantom at $-90^{\circ}$ direction. The experiment were set 65 kVp, 10 mAs, $10{\times}10\;cm^2$, 100 cm(FOD) for the measurement. Digital proportional counting tube survey meter was used for measuring the space scatter dose. Measurement points of horizontal distribution was set up at $30^{\circ}$ interval by increasing 50 cm radius of upside, downside, left and right. Vertical distribution of measurement points were set up for the vertical plane with a radius of at $30^{\circ}$ intervals with 50cm increments. It is concluded that longer distance from the soure of X-ray significantly decrease radiation dose to the patient and use of the radiation protection device should be applied in clinical practice to reduce dose to the patient.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.423-429
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• 2000

The water conditioning experiments of brown rice were performed to verify the effect of brown rice conditioner and to decide the optimum operating variables for the conditioner. The initial moisture contents of 13-14%(wb) brown rice were used as experimental samples. The flow rate of brown rice passing through the conditioner was 2,940 kg/hr and water was supplied proportionally from 80 cc/min to 240 cc/min. The differences between expected and measured moisture contents were neglected except 0.25%(wb) of the maximum differences at 0.2920((cc/min)-water/(kg/min)'%-brown rice) of water supply rate. For the initial moisture contents of 13-14%(wb) brown rice, it was found that a proper water supply rate was 0.2415((cc/min)-water/(kg/min).%-brown rice) and the increments of whole rice was 2.3% compared to non conditioned ones. It was considered that the conditioning process did not influence the whiteness of milled rice because the whiteness differences between conditioned and non-conditioned milled rice were negligible.

• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.503-510
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• 2000

To improve the milling condition of brown rice a continuous type conditioning equipment was developed. To validate the performance of this machine the experimental operation was done at Sa-cheon RPC(Rice Processing Complex) using short grain rough. The initial moisture contents of brown rice were 15.0∼16.5%(w.b) and the flow rate of brown rice passing through the conditioner were 4,370kg per hour. The moisture content differences of brown rice between conditioned and non-conditioned were showed within 0.5%(w.b) This results means that the water injected to brown rice were absorbed to the surface of brown rice evenly. The moisture contents of conditioned treated milled rice were showed slightly higher than that of non-conditioned ones but it was considered that the conditioning process did not affected the weight increasing of milled rice by water supply. For initial moisture contents of 15.0∼16.5%(wb) brown rice it was found that the proper water supply rate was 0.115(cc-water)/(kg·%-brown rice) and the increments of whole rice were 2.2% compared to the non-conditioned ones. it was considered that the conditioning process did not influenced the whiteness of milled rice because the whiteness differences between conditioned and non-conditioned milled rice were negligible. About 18% of electric power which drives the abrasive type rice milling machine was saved at 0.115(cc-water)/(kg·%-brown rice) of water supply rate.

• Laser Solutions
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• v.9 no.3
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• pp.15-21
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• 2006

A Polypropylene (PP) film was ablated using a femtosecond laser with a center wavelength of 785 nm, a pulse width of 184 fs and a repetition rate of 1 kHz. Increments of both pulse energy and the shot number of pulses lead to co-occurrence of photochemical and thermal effect, demonstrated by the spatial expansion of rim on the surface of PP. The shapes of the laser-ablated PP films were imaged by a scanning electron microscope (SEM) and measured a 3D optical measurement system (NanoFocus). And, the oxygen transmission rate (ORT) of periodically laser-ablated PP film were characterized by oxygen permeability tester for modified atmosphere packaging (MAP) of fresh fruit and vegetable. Our results demonstrate that femtosecond pulsed laser is efficient tools for breathable packaging films in modifying the flow of air and gas into and out of a fresh produce container, where the micropatterns are specifically tailored in size, location and number which are easily controlled by laser pulse energy and pulse patterning system.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.90-96
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• 1999

Biodegradable films were prepared by solution blending method in the weight ratio of Chitosan and Algin for the purpose of useful bioimplants. The possibility of bioimplants, which prepared from natural polymers as a skin substitute and food wrapping materials were evaluated by measuring the biodegradability. these biodegradable films were inserted in the back of rats and their biodegradability was investigated by hematological change as a function of time. Rats study showed that low-Chitosan induced increments of monocyte and basophil after 48 hours of implantation. And medium-Chitosan showed increase of lymphocyte and decreased neutrophil counts after 48 hours of implantation. Low, medium Chitosan showed high hemoglobin contents, medium and high Chitosan showed high hematocrit value after 48 hours of implantation. As a result, medium, high-Chitosan induced potential incompatibility in the tissue after 48 hours, but there was little effects to the skin inflammation. The values of biodegradable films, which prepared from natural polymers measured in this study were some satisfiable results at short period with those of ideal skin bioimplants and artificial skin.

• Journal of Preventive Medicine and Public Health
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• v.53 no.3
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• pp.198-204
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• 2020

Objectives: This study aimed to analyze the mortality of heart disease (HD), ischemic heart disease (IHD), and cerebrovascular disease (CeVD) through an age-period-cohort (APC) analysis. Methods: We used data on mortality due to cardiovascular disease from 1995 to 2018 in Japan, as determined by Vital Statistics. Age groups from 0 years to 99 years were defined by 5-year increments, and cohorts were defined for each age group of each year with a 1-year shift. We used Bayesian APC analysis to decompose the changes in the diseases' mortality rates into age, period, and cohort effects. Results: The period effects for all diseases decreased during the analyzed periods for both men and women. The cohort effects for men increased substantially in cohorts born from around 1940 to the 1970s for all types of cardiovascular diseases. The cohort effects of HD decreased in the cohorts born in the 1970s or later for both men and women. Regarding IHD and CeVD, either a non-increase or decrease of cohort effects was confirmed for cohorts born in the 1970s or later for men, but the effects for women showed a continuously increasing trend in the cohorts born in the 1960s or later. Conclusions: The cohort effects for IHD and CeVD showed increasing trends in younger generations of women. This suggests that preventive approaches against cardiovascular diseases are needed, particularly for women.

• Journal of Powder Materials
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• v.14 no.5
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• pp.303-308
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• 2007

The oxidation of $Fe_{73}Si_{16}B_7Nb_3Cu_1$ nanocrystalline powder has been conducted to investigate its influence on the electromagnetic wave absorption characteristics of the soft magnetic material. Oxidation occurred primarily on the surface of nanocrystals. Oxidation reduced the real part of complex permeability due to the reduction of the relative volume of the powder, which otherwise contributes to the permeability. Oxidation reduced the absorption efficiency of the sheet at frequencies over 1GHz, indicating that the relative contribution of skin depth increments to the absorption was not significant. The pulverization and milling process lowered the optimum crystallization temperature of the material by $40{\sim}50^{\circ}C$ because of the internal energy accumulated during the fragmentation and powder thinning processes.

• The Korean Journal of Pain
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• v.10 no.2
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• pp.231-234
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• 1997

Background: The aim of this study was to examine the precise spreading pattern of contrast media in small increments in rabbits. Following pentobarbital anesthesia, the epidural puncture was done surgically with a blunt hook. Methods: The tip of epidural catheter was located at the mid-portion of T7 and T12, in the T7 group (n=7) and T12 group (n=8), respectively. Injection of the contrast media was started at 0.1 mL/kg and increased by 0.1 mL/kg up to a maximum of 0.6, mL/kg, under fluoroscopy. Results: In both groups, the extent of spread increased continuously as a Starling resistor with increasing injected volume(T7 group: $y=4.0+41.8x-28.1x^2$, T12 group: $y=0.2+57.7x-43.5x^2$) the total spread of contrast media was similar. The contrast media spread equally, both rostral and caudal, from catheter tip in T7 group; media spread approximately twice as far rostral as compared to caudal in T12 group (P<0.05). Conclusions: In rabbits, the position of epidural catheter tip should be positioned 2~3 segments below the aimed segment in lower thoracic or lumbar region, whereas in mid-thoracic region it should be positioned close to the level of aimed segment. Rabbits have relatively small epidural space therefore, the volume of injectant should be carefully determined with the suggested equations of this study.

• Laser Solutions
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• v.12 no.1
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• pp.7-13
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• 2009

Engineering ceramics as sapphire are widely used in industry owing to their superior mechanical and corrosion properties. However, micromachining of sapphire is a considerable challenge due to its transparency. Recently, direct ablation of sapphire has been demonstrated with a visible laser pulse at sufficiently high laser intensity. In this work, the theoretical model for pulsed laser ablation of sapphire is suggested and numerical analysis is carried out using the model. Sapphire ablation begins with plasma generation by the laser interaction with surface defects, impurities and contaminations in the initial stage of machining. Subsequent absorption of the visible laser beam can be explained by three mechanisms: metalization of sapphire surface due to the EUV radiation from the hot plasma, increments of surface roughness and temperature-dependent absorption coefficient. Comparison of the computation results with experimental observation indicates that the proposed model of sapphire is reasonable.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.59-67
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• 2014

A dynamic analysis is carried out to provide an evaluation method of running safety for a PSC box bridge located on the Gyung-Bu high speed railway. The numerical models of bridge and train vehicle are developed in detail with corresponding interaction system. Three dimensional skeleton element model of PSC box bridge and 38-degree-of-freedom of vehicle are adopted from the existing properties of KTX bridge and train vehicle. Analysed three direction rotations of vehicle on the bridge and ground tracks are compared for running speeds up to 500 km/h with 10 km/h constant increments. The comparison of the rotations will be an improved evaluation method of Running Safety in stead of the existing standard method.