• Asian-Australasian Journal of Animal Sciences
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• v.29 no.12
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• pp.1734-1741
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• 2016

This study was conducted to examine the effects of adding phytoncide oil extracted from Korean pine nut cone by-product to the diet of dairy cows on milk yield and compositions, fatty acid characteristics, complete blood count and stress response. A total of 74 Holstein cows were used for 30 days and divided into two groups. Each group was given a basal diet (C) or an experimental diet containing phytoncide additives at 0.016% (T) in feed. The results showed that phytoncide feeding had no effect on milk yield. In addition, there were no observed effects on milk composition, but the ratio of fatty acid in milk was significantly affected by the phytoncide diet, and it showed a positive effect. Not only were the major functional fatty acids, conjugated linoleic acid and eicosapentaenoic acid increased, but also ${\omega}6:{\omega}3$ fatty acid ratio was reduced in milk of T group (p<0.05). In blood analysis, the complete blood count showed no significant difference between C and T group on all parameters. However, the cortisol concentration was significantly decreased in T group compared to control (p<0.05). Taken together, we suggest that phytoncide oil does not have a great influence on the physiological changes, but can be a potential feed additive that improves the milk fatty acid and stress resilience in dairy cows. In addition, it will contribute to the development of feed resource, a reduction in feed cost and a lessening of environmental pollution.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.1
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• pp.29-38
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• 2012

The noise generated in the process of obtaining the medical image acts as the element obstructing the image interpretation and diagnosis. To restore the true image from the image polluted from the noise, the total variation optimization algorithm was proposed by the R.O. F (L.Rudin, S Osher, E. Fatemi). This method removes the noise by fitting the balance of the regularity and fidelity. However, the blurring phenomenon of the border area generated in the process of performing the iterative operation cannot be avoided. In this paper, we propose the adaptive total variation method by mapping the control parameter to the proposed transfer function for minimizing boundary error. The proposed transfer function is determined by the noise variance and the local property of the image. The proposed method was applied to 464 tooth images. To evaluate proposed method performance, PSNR which is a indicator of signal and noise's signal power ratio was used. The experimental results show that the proposed method has better performance than other methods.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.330-337
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• 2021

3D printing is not only at the fundamental study and small-scale level, but has recently been producing buildings that can be inhabited by people. Buildings require a lot of cost and labor to work on the form work, but if 3D printing is applied to the building, the construction industry is received attention from technologies using 3D printing as it can reduce the construction period and cost. 3D printing technology for buildings can be divided into structural and non-structural materials, of which 3D printing is applied to non-structural materials. Because 3D printing needs to be additive manufacturing, control such as curing speed and workability is needed. Since cement mortar has a large shrinkage due to evaporation of water, cement polymer dispersion is used to improve the hardening speed, workability, and adhesion strength. The addition of polymer dispersion to cement mortar improves the tensile strength and brittleness between the cement hydrate and the polymer film. Cement mortar using polymer materials can be additive manufacturing but it has limited height that can be additive manufacturing due to its high density. When light-weight materials are mixed with polymer cement mortar, the density of polymer cement mortar is lowered and the height of additive manufacturing, so it is essential to use light-weight materials. However, the use of EVA redispersible polymer powder and light-weight materials, additional damage such as cracks in cement mortar can occur at high temperatures such as fires. This study produced a test specimen incorporating light-weight materials and EVA redispersible polymer powder to produce exterior building materials using 3D printing, and examined flame resistance performance through water absorption rate, length change rate, and cone calorimeter test and non-flammable test. From the test result, the test specimen using silica sand and light-weight aggregate showed good flame resistance performance, and if the EVA redispersible polymer powder is applied below 5%, it shows good flame resistance performance.

• Korean Journal of Dental Materials
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• v.46 no.1
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• pp.1-10
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• 2019

There are several causes of tooth discoloration following root canal treatment. In this study, we evaluated the effects of sealers on tooth discoloration and internal bleaching. Twenty-four teeth were divided into 4 groups: control group, AH plus, Endosequece BC, and MTA fillapex group. Root canal filling was performed using each sealer conventionally and non-vital bleaching was performed with sodium perborate. The L, a, and b values were measured using Vita easyshade. Tooth discoloration after root canal treatment occurs irrespective of the type of sealers and may cause discoloration with only gutta-percha cone. The effect of non-vital bleaching following the use of calcium silicate-based sealers such as Endosequece BC and MTA fillapex was higher than that of AH plus. Therefore, it needs careful use of sealers in endodontics and calcium silicate-based sealers have advantages of bleaching in case of discolored tooth.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.4
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• pp.241-248
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• 1993

An experiment was conducted in 1990~1991 to study the effects of various soil amelioration on the soil productivity and machine workability at tidal land paddy field of Kyewhado Substation, Homam Crop Experiment Station. The soil, Munpo Series(fine sandy loam, Typic Fluvaquents) was treated with gipsum, rice straw, rice straw compost and foreign soil(at 20cm depth) after deep ploughing. The results are surmerized as follows. 1. Sand and clay were slightly increased, while silt was slightly decreased in the rice straw and compost plots. The soil texture was changed from loam to sand loam by the addition of foreign soil 2. Soil bulk density and porosity was decreased in the rice straw, compost and foreign soil addition plots. 3. Cone penetration resistance was $12.5kg/cm^2$ at 10cm of soil depth before experiment and $12.5kg/cm^2$ at 20cm of soil depth after experiment except control, and the root zone was expended down to 20cm. 4. Soil salt content before experiment was 0.46 and 0.48% for surface soil(10cm) and subsoil(20cm), respectively ; The salt content of ameliorated plot was 0.26~0.32% and 0.16~0.31%, respectively, indicating good leaching of soil salt by the soil improvements. 5. The yields of rice in different treatments were in the order of the foreign soil addition > compost > gypsum > rice straw > control.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.4
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• pp.373-379
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• 1988

This experiment was carried out to investigate the effects of long-term applications of rice straw and compost on the physical and mechanical properties of paddy fields and the yearly variation of rice yield in Fluvio-Marine plain of Jeonbug series. Amounts of rice straw and compost applied in this experiment were 500kg/10a, 1,000kg/10a respectively, and the nitrogen levels were 0, 15 and 20kg/10a. This experiment were continued for 9 years from 1979 to 1987. The results are summarized as follows: 1. Clay and silt ratios were decreased but versa in sand ratio, by the long-term application of rice straw and compost. 2. Bulk density in the long-term application of organic matter was lower in surface soil of non-application than nitrogen application (15kg/10a) and in rice straw than compost. 3. Solid ratio went down, but liquid and gaseous ratio went up especially, by organic matter application liquid ratio were increased by compost and gaseous ratio were increased by in rice straw. 4. Aggregates of bigger than 2mm were increased by long-term application of organic matter, and the effects was better in rice straw than compost. Accumulative aggregate of 2mm was 66.5% in nitrogen of 15kg/ 10a with rice straw, which showed the increase of 9.1% in comparison with the non-application of nitrogen and organic matter. 5. Liquid limit, plastic limit and plastic index were high in order of rice straw, compost and control, and liquid index was lower in compost than in rice straw. 6. Cole value was higher in vertical than horizontal and highest in the application of rice straw with nitrogen of 15kg/10a. Cone and shearing resistance were lowest in the application of rice straw with nitrogen. In total vertical pressure friction was higher in the long-term application of organic matter than control. 7. The change of yield index was higher in the long-term application of compost than rice straw in non-nitrogen and it showed the yearly competitive variation between the long-term application of compost and rice straw in nitrogen of 10kg/10a. In nitrogen application of 20kg/10a, it was increased from 6th year by rice straw application.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.150-156
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• 2000

Purpose : Stereotactic radiation therapy (SRT) can deliver highly focused radiation to a small and spherical target lesion with very high degree of mechanical accuracy. For non-spherical and large lesions, however, inclusion of the neighboring normal structures within the high dose radiation volume is inevitable in SRT This is to report the beam shaping using the partial closure of the independent jaw in SRT and the verification of dose calculation and the dose display using a home-made soft ware. Materials and Methods : Authors adopted the idea to partially close one or more independent collimator jaw(5) in addition to the circular collimator cones to shield the neighboring normal structures while keeping the target lesion within the radiation beam field at all angles along the arc trajectory. The output factors (OF's) and the tissue-maximum ratios (TMR's) were measured using the micro ion chamber in the water phantom dosimetry system, and were compared with the theoretical calculations. A film dosimetry procedure was peformed to obtain the depth dose profiles at 5 cm, and they were also compared with the theoretical calculations, where the radiation dose would depend on the actual area of irradiation. Authors incorporated this algorithm into the home-made SRT software for the isodose calculation and display, and was tried on an example case with single brain metastasis. The dose-volume histograms (DVH's) of the planning target volume (PTV) and the normal brain derived by the control plan were reciprocally compared with those derived by the plan using the same arc arrangement plus the independent collimator jaw closure. Results : When using 5.0 cm diameter collimator, the measurements of the OF's and the TMR's with one independent jaw set at 30 mm (unblocked), 15.5 mm, 8.6 mm, and 0 mm from th central beam axis showed good correlation to the theoretical calculation within 0.5% and 0.3% error range. The dose profiles at 5 cm depth obtained by the film dosimetry also showed very good correlation to the theoretical calculations. The isodose profiles obtained on the home-made software demonstrated a slightly more conformal dose distribution around the target lesion by using the independent jaw closure, where the DVH's of the PTV were almost equivalent on the two plans, while the DVH's for the normal brain showed that less volume of the normal brain receiving high radiation dose by using this modification than the control plan employing the circular collimator cone only. Conclusions : With the beam shaping modification using the independent jaw closure, authors have realized wider clinical application of SRT with more conformal dose planning. Authors believe that SRT, with beam shaping ideas and efforts, should no longer be limited to the small spherical lesions, but be more widely applied to rather irregularly shaped tumors in the intracranial and the head and neck regions.

• Journal of Korean society of Dental Hygiene
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• v.4 no.1
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• pp.49-64
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• 2004

This study is designed to conduct a questionnaire research into the safety control and the actual condition of radiography by working with dentistry belonging to university hospitals, dental hospitals and dental clinics for three months ranging from August, 2003 to October, 2003. The researcher came to the following conclusions. 1. The research on the current condition of possessed radiational equipment shows that 61.2 percent of the subjects had one intraoral radiation medicine and that 70.1 percent of the subjects had more than one extraoral radiation medicine and that 37.3 percent of the subjects had more than one digital radiation medicine. 2. Most of intraoral radiography (82.1%) was conducted by dental hygienists, and 7.5 percent of intraoral radiography was conducted by nurse aids. On the other hand, most of extraoral radiography (76.6%) was conducted by dental hygienists and digital radiography was conducted by dental hygienists(60.6%), dentists(32.0%) and radiographer(80.0%). 3. The less-than 1-meter-long distance between cone and the radiographer accounted for 44.8 percent. And the more-than 1.6-meter-long distance accounted for no more than 13.4 percent. The exposure time per standard film which was adjusted to each part accounted for 71.6 percent. Fixing the film on the part of healthy patients accounted for 76.1 percent. Fixing the film of elderly patients and children patients by the radiographer accounted for 43.3 percent. 4. The average daily photographing frequency of standard films stood at six to ten pieces(31.3%), and the average weekly photographing frequency of bitewing films stood at less than one piece(47.8%), and the dentistries where bitewing films were not employed accounted for 25.4%. The subjects whose average weekly photographing freqeuncy of occlusal films stood at less than a piece accounted for 59.7 percent. The dentistries whose average weekly photographing frequency of pediatric films stood at one to five pieces accounted for 41.8 percent. In case of panorama & cephalo, one to five pieces on a weekly average accounted for 36.2 percent. The dentistries whose average daily photographing frequency of digital radiation medicine stood at less than 1 piece accounted for 40.0 percent. 5. The research on the use of protective clothes shows that pregnant ·women only accounted for 31.3 percent. In regard to the use of protective clothes in case of the radiographers fixing films, the cases where no protective clothes were employed accounted for 88.1 percent. The reason was said to he attributable to the trouble related to wearing the clothes(54.2%). 6. The survey on the measurement of exposure dose shows that the cases where no measurement was made accounted for 76.1 percent. As far as the measurement methods of exposure dose was concerned, the employment of film badge accounted for 68.8 percent. The subjects turned out to conduct measurement of exposure dose every third month, which accounted for 43.8 percent. The barriers to the measurement of measurement of exposure dose were attributable to the recognition that a little amount of exposure dose need not be measured(29.9%). 7. The survey on the distinction of radiation rooms and clinic rooms reveals that the cases where radiation rooms exclusively existed accounted for 67.2 percent. 43.3 percent of the subjects turned out to have only one protective garment, and 49.3 percent of the subjects proved to conduct a periodical checkup of radiational equipment. The survey on the examination certificates of radiational generators and protective facilities indicates that 80.6 percent of the subjects had the certificates. The research also shows that the subjects with the marks indicating the radiational areas accounted for 70.1 percent. And trustees turned out to handle developing solutions and fixing solutions.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.199-206
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• 2014

Purpose : According to the rapid increase recently in image-guided radiation therapy, It is necessary to control of the image guidance system completely. In particular for the main subject to the accuracy of image guided radiation therapy device to be done essentially the quality assurance. We made efficient phantom in AMC for the management of the accurate and efficient. Materials and Methods : By setting up of five very important as a quality assurance inventory of the Image guidance system, we made (AMC G-Box) phantom for quality assurance efficient and accurate. Quality assurance list were the Iso-center align, the real measurement, the center align of four direction, the accuracy of table movement and the reproducibility of Hounsfield Unit. The rectangular phantom; acrylic with a thickness of 1 cm to $10cm{\time}10cm{\time}10cm$ was inserted the three materials with different densities respectively for measure the CBCT HU. The phantom was to perform a check of consistency centered by creating a marker that indicates the position of the center fixed. By performing the quality assurance using the phantom of existing, comparing the resulting value to the different resulting value using the AMC G-Box, experiment was analyzed time and problems. Therapy equipment was used Varian device. It was measured twice at 1-week intervals. Results : When implemented quality assurance of an image guidance system using AMC G-Box and a phantom existing has been completed, the quality assurance result is similar in $0.2mm{\pm}0.1$. In the case of the conventional method, it was 45 minutes at 30 minutes. When using AMC G-Box, it takes 20 minutes 15 minutes, and declined to 50% of the time. Conclusion : The consistency and accurate of image guidance system tend to decline using device. Therefore, We need to perform thoroughly on the quality assurance related. It needs to be checked daily to consistency check especially. When using the AMC G-Box, It is possible to enhance the accuracy of the patient care and equipment efficiently performing accurate quality assurance.

• Progress in Medical Physics
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• v.5 no.2
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• pp.57-68
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• 1994

Purpose : The purposes are to discuss the reason to measure dose distributions of circular small fields for stereotactic radiosurgery based on medical linear accelerator, finding of beam axis, and considering points on dosimetry using home-made small water phantom, and to report dosimetric results of 10MV X-ray of Clinac-18, like as TMR, OAR and field size factor required for treatment planning. Method and material : Dose-response linearity and dose-rate dependence of a p-type silicon (Si) diode, of which size and sensitivity are proper for small field dosimetry, are determined by means of measurement. Two water tanks being same in shape and size, with internal dimension, 30${\times}$30${\times}$30cm$^3$ were home-made with acrylic plates and connected by a hose. One of them a used as a water phantom and the other as a device to control depth of the Si detector in the phantom. Two orthogonal dose profiles at a specified depth were used to determine beam axis. TMR's of 4 circular cones, 10, 20, 30 and 40mm at 100cm SAD were measured, and OAR's of them were measured at 4 depths, d$\sub$max/, 6, 10, 15cm at 100cm SCD. Field size factor (FSF) defined by the ratio of D$\sub$max/ of a given cone at SAD to MU were also measured. Result : The dose-response linearity of the Si detector was almost perfect. Its sensitivity decreased with increasing dose rate but stable for high dose rate like as 100MU/min and higher even though dose out of field could be a little bit overestimated because of low dose rate. Method determining beam axis by two orthogonal profiles was simple and gave 0.05mm accuracy. Adjustment of depth of the detector in a water phantom by insertion and remove of some acryl pates under an auxiliary water tank was also simple and accurate. TMR, OAR and FSF measured by Si detector were sufficiently accurate for application to treatment planning of linac-based stereotactic radiosurgery. OAR in field was nearly independent of depth. Conclusion : The Si detector was appropriate for dosimetry of small circular fields for linac-based stereotactic radiosurgery. The beam axis could be determined by two orthogonal dose profiles. The adjustment of depth of the detector in water was possible by addition or removal of some acryl plates under the auxiliary water tank and simple. TMR, OAR and FSF were accurate enough to apply to stereotactic radiosurgery planning. OAR data at one depth are sufficient for radiosurgery planning.