• The Journal of Korean Society for Radiation Therapy
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• v.34
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• pp.21-30
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• 2022

Purpose: The purpose of this study is to evaluate the effectiveness of oral positioning stent, the BinkieRT^TM in radiation treatment for head and neck cancer patients in terms of tongue positions reproducibility, tongue doses and material properties. Materials and Methods: 24 cases using BinkieRT^TM during radiation treatments were enrolled. The tongue was contoured on planning CT and CBCT images taken every 3 days during treatment, and then the DSC and center of tongue shift values were analyzed to evaluate the reproducibility of the tongue. The tongue dose was compared in terms of dose distribution when using BinkieRT^TM and different type of oral stents (mouthpiece, paraffin wax). Randomly selected respective 10 patients were measured tongue doses of initial treatment plan for nasal cavity and unilateral parotid cancer. Finally, In terms of material evaluation, HU and relative electron density were identified in RTPS. Results: As a result of DSC analysis, it was 0.8 ± 0.07, skewness -0.8, kurtosis 0.61, and 95% CI was 0.79~0.82. To analyze the deviation of the central tongue shift during the treatment period, a 95% confidence interval for shift in the LR, SI, and AP directions were indicated, and a one-sample t-test for 0, which is an ideal value in the deviation(n=144). As a result of the t-test, the mean and SD in the LR and SI directions were 0.01 ± 0.14 cm (p→.05), 0.03 ± 0.25 cm (p→.05), and -0.08 ± 0.25 cm (p ←.05) in the AP direction. In the case of unilateral parotid cancer patients, the Dmean to the tongue of patients using BinkieRT^TM was 16.92% ± 3.58% compared to the prescribed dose, and 23.99% ± 10.86% of patients with Paraffin Wax, indicating that the tongue dose was relatively lower when using BinkieRT^TM (p←.05). On the other hand, among nasal cavity cancer patients, the Dmean of tongue dose for patients who used BinkieRT^TM was 4.4% ± 5.6%, and for those who used mouthpiece, 5.9% ± 6.8%, but it was not statistically significant (p→.05). The relative electron density of Paraffin Wax, BinkieRT^TM and Putty is 0.94, 0.99, 1.26 and the mass density is 0.95, 0.99 and 1.32 (g/cc), Transmission Factor is 0.99, 0.98, 0.96 respectively. Conclusion: The result of the tongue DSC analysis over the treatment period was about 0.8 and Deviation of the center of tongue shifts were within 0.2 cm, the reproducibility was more likely excellent. In the case of unilateral head and neck cancer patients, it was found that the use of BinkieRT^TM rather than Paraffin Wax or Putty can reduce the unnecessary dose irradiated to the tongue. This study might be useful to understand of BinkieRT^TM's properties and advantages. And also it could be another considered option as oral stent to keep the reproducibility of tongue and reducing dose during head and neck radiation treatments.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.339-348
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• 2006

Objective: With development of the skeletal anchorage system, orthodontic mini-implant (OMI) assisted on masse sliding retraction has become part of general orthodontic treatment. But compared to the emphasis on successful anchorage preparation, the control of anterior teeth axis has not been emphasized enough. Methods: A 3-D finite element Base model of maxillary dental arch and a Lingual tipping model with lingually inclined anterior teeth were constructed. To evaluate factors influencing the axis of anterior teeth when OMI was used as anchorage, models were simulated with 2 mm or 5 mm retraction hooks and/or by the addition of 4 mm of compensating curve (CC) on the main archwire. The stress distribution on the roots and a 25000 times enlarged axis graph were evaluated. Results: Intrusive component of retraction force directed postero-superiorly from the 2 mm height hook did not reduce the lingual tipping of anterior teeth. When hook height was increased to 5 mm, lateral incisor showed crown-labial and root-lingual torque and uncontrolled tipping of the canine was increased.4 mm of CC added to the main archwire also induced crown-labial and root-lingual torque of the lateral incisor but uncontrolled tipping of the canine was decreased. Lingual tipping model showed very similar results compared with the Base model. Conclusion: The results of this study showed that height of the hook and compensating curve on the main archwire can influence the axis of anterior teeth. These data can be used as guidelines for clinical application.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.99-106
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• 2007

Purpose: The patient's position and anatomy during the treatment course little bit varies to some extend due to setup uncertainties and organ motions. These factors could affected to not only the dose coverage of the gross tumor but over dosage of normal tissue. Setup uncertainties and organ motions can be minimized by precise patient positioning and rigid immobilization device but some anatomical site such as prostate, the internal organ motion due to physiological processes are challenge. In planning procedure, the clinical target volume is a little bit enlarged to create a planning target volume that accounts for setup uncertainties and organ motion as well. These uncertainties lead to differences between the calculated dose by treatment planning system and the actually delivered dose. The purpose of this study was to evaluate the differences of interfractional displacement of organ and GTV based on the tomoimages. Materials and Methods: Over the course of 3 months, 3 patients, those who has applied rectal balloon, treated for prostatic cancer patient's tomoimage were studied. During the treatment sessions 26 tomoimages per patient, Total 76 tomoimages were collected. Tomoimage had been taken everyday after initial setup with lead marker attached on the patient's skin center to comparing with C-T simulation images. Tomoimage was taken after rectal balloon inflated with 60 cc of air for prostate gland immobilization for daily treatment just before treatment and it was used routinely in each case. The intrarectal balloon was inserted to a depth of 6 cm from the anal verge. MVCT image was taken with 5 mm slice thickness after the intrarectal balloon in place and inflated. For this study, lead balls are used to guide the registration between the MVCT and CT simulation images. There are three image fusion methods in the tomotherapy, bone technique, bone/tissue technique, and full image technique. We used all this 3 methods to analysis the setup errors. Initially, image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours and then the radiation therapist registered the MVCT images with the CT simulation images based on the bone based, rectal balloon based and GTV based respectively and registered image was compared with each others. The average and standard deviation of each X, Y, Z and rotation from the initial planning center was calculated for each patient. The image fusions were based on the visual alignment of lead ball, CT anatomy and CT simulation contours. Results: There was a significant difference in the mean variations of the rectal balloon among the methods. Statistical results based on the bone fusion shows that maximum x-direction shift was 8 mm and 4.2 mm to the y-direction. It was statistically significant (P=<0.0001) in balloon based fusion, maximum X and Y shift was 6 mm, 16mm respectively. One patient's result was more than 16 mm shift and that was derived from the rectal expansions due to the bowl gas and stool. GTV based fusion results ranging from 2.7 to 6.6 mm to the x-direction and 4.3$\sim$7.8 mm to the y-direction respectively. We have checked rotational error in this study but there are no significant differences among fusion methods and the result was 0.37$\pm$0.36 in bone based fusion and 0.34$\pm$0.38 in GTV based fusion.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.77-81
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• 2009

Purpose: The PET of the PET/CT (Positron Emission Tomography/Computed Tomography) quantitatively shows the biological and chemical information of the body, but has limitation of presenting the clear anatomic structure. Thus combining the PET with CT, it is not only possible to offer the higher resolution but also effectively shorten the scanning time and reduce the noises by using CT data in attenuation correction. And because, at the CT scanning, the contrast media makes it easy to determine a exact range of the lesion and distinguish the normal organs, there is a certain increase in the use of it. However, in the case of using the contrast media, it affects semi-quantitative measures of the PET/CT images. In this study, therefore, we will be to establish the reliability of the SUV (Standardized Uptake Value) with CT data correction so that it can help more accurate diagnosis. Materials and Methods: In this experiment, a total of 30 people are targeted - age range: from 27 to 72, average age : 49.6 - and DSTe (General Electric Healthcare, Milwaukee, MI, USA) is used for equipment. $^{18}F$- FDG 370~555 MBq is injected into the subjects depending on their weight and, after about 60 minutes of their stable position, a whole-body scan is taken. The CT scan is set to 140 kV and 210 mA, and the injected amount of the contrast media is 2 cc per 1 kg of the patients' weight. With the raw data from the scan, we obtain a image showing the effect of the contrast media through the attenuation correction by both of the corrected and uncorrected CT data. Then we mark out ROI (Region of Interest) in each area to measure SUV and analyze the difference. Results: According to the analysis, the SUV is decreased in the liver and heart which have more bloodstream than the others, because of the contrast media correction. On the other hand, there is no difference in the lungs. Conclusions: Whereas the CT scan images with the contrast media from the PET/CT increase the contrast of the targeted region for the test so that it can improve efficiency of diagnosis, there occurred an increase of SUV, a semi-quantitative analytical method. In this research, we measure the variation of SUV through the correction of the influence of contrast media and compare the differences. As we revise the SUV which is increasing in the image with attenuation correction by using contrast media, we can expect anatomical images of high-resolution. Furthermore, it is considered that through this trusted semi-quantitative method, it will definitely enhance the diagnostic value.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.391-400
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• 1997

Background : Bronchoscopy is an essential procedure for identifying the bleeding site and evaluating cause of hemoptysis. However, it is controversial regarding to the timing of bronchoscopy in patients with hemoptysis. Early bronchoscopy, which was performed during hemoptysis or with 48hour after cessation of bleeding, was better for identifying the site of bleeding compared with delayed bronchoscopy, which was performed 48 hours after cessation of bleeding. The diagnostic yield of identifying the bleeding site by bronchoscopy was variable in reported literature and the safety of early bronchoscopy was not mentioned in previous literature. Therefore, we evaluated the efficacy and safety of early bronchoscopy in patients with hemoptysis. Method : From October 1994 to August 1996 in Samsung Medical Center, bronchoscopy was performed in patients with hemoptysis. Early bronchoscopy was performed prospectively during hemoptysis or within 48 hours after cessation of bleeding from May 1995 to August 1996. Delayed bronchoscopy group included patients who did not received early bronchoscopy at the same period or in whom bronchoscopy was performed 48 hour after cessation of bleeding from October 1994 to May 1995. Results : Early bronchoscopy group was performed 73 times in 71 patients. Delayed bronchoscopy was performed in 57 times in 55 patients. There was no difference as to amount and underlying cause of hemoptysis between both groups. Indentification of bleeding site by visualizing active bleeding was significantly higher in early bronchoscopy (38.3%) than delayed bronchoscopy group (8.7%)(p < 0.05). Indentification of bleeding site by bleeding after clot removal was 8 in early and 10 in delayed bronchoscopy. Indentification of bleeding site by visualizing active bleeding and bleeding after clot removal was 36 in early and 15 patients in delayed bronchoscopy(p > 0.05). Causes of hemoptysis was found in 18 patients in early and 16 patients in delayed bronchoscopy group. patients who had early bronchoscopy underwent surgery. We diagnosed the site of bleeding in 4 patients preoperatively. In 3 patients we made a treatment plan promptly right after bronchoscopy. Among early bronchoscopy group, bleeding over 100cc during bronchoscopy occurred in 2 patients. In early bronchoscopy group there was no other major complication during bronchoscopy. Conclusion : In patients with hemoptysis, early bronchoscopy which performed within 48 hours after cessation of bleeding was more effective procedure for identifying the bleeding site than delayed bronchoscopy which was performed after 48 hour cessation of bleeding.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.251-257
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• 2010

The experiment was conducted to find out the nutritive value and microbial status of different wholesale cuts of goat carcass. The meat sample (4 cuts from each animal $\times$ 3 different age groups $\times$ 3 animals in each group = 36 samples) was obtained from 1-, 2-, and 3-year aged goats. The whole sale cuts were shoulder, rack, loin and leg of each goat carcass. To assess the quality of meat sample, the general appearance, color, smell, juiciness, proximate composition, pH, total bacteria, coliform bacteria, and yeast were studied. The mean pH value of different cuts ranges from 5.65-5.69 didn't differ significantly, but due to age differences the pH values (5.59-5.74) differed significantly (p < 0.01). The values of juiciness in different ages ranged from 32.24-42.10% which differed significantly (p < 0.01). The marbling of the cuts of rack portion was more pronounced than that of other cuts. The ranges of crude protein (CP) content of goat carcass (20.78-27.71%) differed significantly (p < 0.01) and leg portion contained higher CP than other portion. Fat contents of different cuts ranged from 2.66-11.47% differed significantly (P < 0.01). The moisture content of the carcass differed significantly which ranged from 69.20-73.31%. The ash content of the cuts of 1-year aged groups (0.99 $\pm$ 0.13%) was higher than that of other age groups and differed significantly (P < 0.01). The calcium (Ca) content did not differ significantly. The phosphorus (P) content was higher in one year old goat (0.15 $\pm$ 0.03%) than that of the goats of other ages. The total viable count (TVC) content of microorganisms ranging from 5.05-5.15 log cfu/g at different ages did not differ significantly. The coliform count (CC) of different cuts differed significantly (P < 0.01) which ranged from 2.56-3.05 log cfu/g; it also differed significantly (P < 0.05) in different ages (2.79-2.84 log cfu/g) and was higher in 1 year old goat carcass. The yeast count differed significantly in different cuts (P < 0.01) and ages (P < 0.05). From the study it is concluded that the age and different wholesale cuts have direct influence on quality of goat carcass.

• Korean Journal of Environment and Ecology
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• v.21 no.3
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• pp.197-206
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• 2007

This study was conducted to survey the population of water birds wintering at the seven coastal wetlands of Jeollanam province including Suncheon Bay and Yeongsan Lake, from 2000 through 2003. The 90 species and 857,570 individuals in total were sighted at the seven survey sites. We classified the wintering water birds into seventeen groups of taxa based on the similar ecological attributes, among which, eight groups were found to inhabit the water surface or riparian areas. Classified groups that showed higher rate of using bay areas than that of lake areas were in the order of waders, gulls and swans. On the other hand, the groups that showed higher rate of using lake areas than that of using bay areas were revealed in the order of dabbling ducks, grebes and geese. In conclusion, there was a difference in the pattern between the two classified groups. As a result of the UPGMA cluster analysis using CCs ($S{\varnothing}rensen'a$ index of similarity and Ro (Horn's index of community overlap), the results showed that Suncheon Bay had the most unique species formation out of the seven areas. Bay and lake areas were different from each other in the formation of species and Individuals. As a result of combining the index rank according to the maximum aggregate count, the Suncheon Bay is ranked the highest in importance of the habitats for water birds, followed by the order of Boseong-Deukryang Bay, Gangjin Bay, Gocehongam Lake, Geumho Lake, Yeomam Lake, and Yeongsan Lake. Considered overall, the importance of the bay areas was relatively higher than that of reclaimed lake areas.

• Korean Journal of Remote Sensing
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• v.37 no.2
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• pp.337-357
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• 2021

Because the growth of paddy rice is affected by meteorological factors, the selection of appropriate meteorological variables is essential to build a rice yield prediction model. This paper examines the suitability of multiple meteorological datasets for the rice yield modeling in South Korea, 1996-2019, and a hindcast experiment for rice yield using a machine learning method by considering the nonlinear relationships between meteorological variables and the rice yield. In addition to the ASOS in-situ observations, we used CRU-JRA ver. 2.1 and ERA5 reanalysis. From the multiple meteorological datasets, we extracted the four common variables (air temperature, relative humidity, solar radiation, and precipitation) and analyzed the characteristics of each data and the associations with rice yields. CRU-JRA ver. 2.1 showed an overall agreement with the other datasets. While relative humidity had a rare relationship with rice yields, solar radiation showed a somewhat high correlation with rice yields. Using the air temperature, solar radiation, and precipitation of July, August, and September, we built a random forest model for the hindcast experiments of rice yields. The model with CRU-JRA ver. 2.1 showed the best performance with a correlation coefficient of 0.772. The solar radiation in the prediction model had the most significant importance among the variables, which is in accordance with the generic agricultural knowledge. This paper has an implication for selecting from multiple meteorological datasets for rice yield modeling.

• Journal of the Korean Society for Marine Environment & Energy
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• v.20 no.1
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• pp.26-36
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• 2017

Korea is preparing an offshore carbon capture, transport and storage (CCS) demonstration project which is recognized as one of important $CO_2$ reduction technologies to mitigate climate change. The offshore CCS project aims to transport, inject and store large amount of $CO_2$ into offshore geologic formation, and has a potential risk of leakage which might cause disastrous damage to human health, environment and property. Therefore, in order to ensure the safety of the offshore CCS project, a strict HSE (health, safety and environment) management plan and its implementation are required throughout the project life cycle. However, there are no HSE domestic laws or regulations applicable to CCS projects, and the related research is insufficient in Korea. For the derivation of the essential and urgent requirement in HSE management framework applicable to the offshore CCS project in Korea, we analysed the HSE management methodologies and foreign CCS HSE management guidelines and cases. First, this paper has analyzed ISO 31000, a generalized risk management principles. Second, we have investigated the HSE management practices of CCS projects in Norway and UK. Based on the analyses, we suggested the necessity of developing the HSE Philosophy and the HSE management process through the whole life cycle. Application of HSE management in early phase of an offshore CCS project will promote systematic and successful project implementation in a cost-effective and safe way.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.150-154
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• 2010

Purpose: Ejection fraction (EF) is one of the most important factors that evaluate heart function. Recently, according to echocardiography and myocardial perfusion SPECT, the number of gated blood pool scan (planar GBP) is declining. Measurement of left ventricular ejection fraction using gated blood pool SPECT (GBPS) is known as relatively correspond with echocardiography. We compared EF derived from plnar GBP, GBPS and echocadiography using modified simpson method to determine the accuracy. Materials and Methods: From January 2007 to June 2010, planar GBP and GBPS were performed on 34 patients who admitted to Pusan National University Hospital (men 23, women 11, mean age $52.6{\pm}27.2$). Each patient was injected with $^{99m}{TcO_4}^-$ of 20 mCi after pyrophosphate injection and then scanned using both planar GBP and GBPS techniques. For image analysis, we use ADAC Laboratories, Ver. 4.20 software. The result analyzed was processed by SPSS 17.0 Win statistic program and statistical method applied in data analysis is one-way anova, Tukey's post hoc test, pearson correlation test. Results: One-way anova test show no significant difference (planar GBP $56.3{\pm}13.9%$; GBPS $60.4{\pm}16.0%$; echocardiography $59.1{\pm}14.4%$, p=0.486, p>0.05). Tukey's post hoc test show no significant difference (planar GBP-echocardiography p=0.697; GBPS-echocardiography p=0.928; planar GBP-GBPS p=0.469, p>0.05). Values for EF obtained with planar GBP and GBPS correlated well with those obtained with echocardiography (planar-echocardiography r=0.697; GBPS-echocardiography r=0.928; planar GBP-GBPS r=0.469). Conclusion: The problems of accuracy and reproducibility for planar GBP still remain. But planar GBP is a safe and non-invasive method. In addition, planar GBP is useful to evaluate patient with low resolution echocardiography images. GBPS is not appicated clinically. but GBPS can be obtain various left ventricular functional parameters. planar GBP, GBPS and echocardiography show a good correlation between each other. Therefore, planar GBP and GBPS are useful for evaluating left ventricular ejection fraction.