• Investigative Magnetic Resonance Imaging
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• v.17 no.2
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• pp.133-143
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• 2013

Purpose : To evaluate and compare the accuracy of magnetic resonance imaging (MRI) and ultrasound (US) for detection and estimation of invasion depth of colorectal carcinoma (CRC) by correlation with histopathologic findings in vitro, and to find out the best MR pulse sequence for accurate delineation of tumor from surrounding normal tissue. Materials and Methods: Resected specimens of CRC from 45 patients were examined about tumor detectability and invasion depth of US using high frequency (5-17 MHz) linear transducer in a tube filled with normal saline and MRI in a 8-channel quadrate head coil. The institutional review board approved this study and informed consent was waived. MRI with seven pulse sequences of in- and out-of-phases gradient echo T1 weighted images, fast spin echo T2 weighted image and its fat suppression image, fast imaging employing steady-state acquisition (FIESTA) and its fat suppression image, and diffusion weighted image (DWI) were performed. In each case, both imaging findings of MRI and US were evaluated independently for detection and estimation of invasion depth of tumor by consensus of two radiologists and were compared about diagnostic accuracy according to the histopathologic findings as reference standard. Seven MR pulse sequences were evaluated on the point of accurate delineation of tumor from surrounding normal tissue in each specimen. Results: In specimens of CRC, both imaging modalities of MRI (91.1%) and US (86.7%) showed relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of tumor. In early CRC, diagnostic accuracy of US was 87.5% and that of MRI was 75.0%. There was no statistically significant difference between two imaging modalities (p > 0.05). The best pulse sequence among seven MR sequences for accurate delineation of tumor from surrounding normal tissue in each specimen of CRC was fast spin echo T2 weighted image. Conclusion: MRI and US show relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of resected specimen of CRC. The most excellent pulse sequence of MRI for accurate delineation of tumor from surrounding normal tissue in CRC is fast spin echo T2 weighted image.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.4
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• pp.350-359
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• 2005

Sagittal split ramus osteotomy(SSRO) has been commonly performed in the mandibular prognathism. The previous studies of the mandibular anatomy for SSRO have mostly been used in dry skull without consideration of age, sex or jaw relationship of patients. This study was performed to evaluate the location of mandibular canal and the anatomy of ramus, such as the location of mandibular lingula and the ramal bone marrow, which were associated with SSRO procedures, in the patients with mandibular prognathism and normal young adults by using computerized tomographs(CT) and 3D images. The young adults at their twenties, who were considered to complete their skeletal growth, and seen in the Department of Orthodontics and Oral and Maxillofacial Surgery in Chonnam National University Hospital between March 2000 and May 2003, were selected. This study was performed in 30 patients (15men, 15women) who were diagnosed as skeletal class I normal relationship, and another 30 patients (15men, 15women) who were diagnosed as skeletal class III relationship upon clinical examination and lateral cephalometric radiographs. The patients were divided into 2 groups : Class I group, the patients who had skeletal class Ⅰ normal relationship(n=30, 15men, 15women), and Class III group, the patients who had skeletal class III relationship(n=30, 15men, 15women). Facial CT was taken in all patients, and pure 3D mandibular model was constructed by V-works version 4.0. The occlusal plane was designed by three points, such as the mesiobuccal cusp of both mandibular 1st molar and the incisal edge of the right mandibular central incisor, and used as a reference plane. Distances between the tip of mandibular lingula and the occlusal plane, the sigmoid notch, the anterior and the posterior borders of ramus were measured. The height of ramal bone marrow from the occlusal plane and the distance between mid-point of mandibular canal and the buccal or lingual cortex of the mandible in the 1st and 2nd molars were measured by V-works version 4.0. Distance(Li-OP) between the occlusal plane and the tip of mandibular lingula of Class III Group was longer than that of Class I Group in men(p<0.01), but there was no significant difference in women between both groups. Distance(Li-SN) between the sigmoid notch and the tip of mandibular ligula of Class III group was longer than that of Class I Group in men(p<0.05), but there was no significant difference in women between both groups. Distance(Li-RA) between the anterior border of ramus and the tip of mandibular lingula of Class III Group was shorter than that of Class I Group in men and women(p<0.01). Distance(Li-RP) between the posterior border of ramus and the tip of mandibular lingula of Class III Group was slightly shorter than that of Class I Group in men(p<0.05), but there was no significant difference in women between both groups. Distance(RA-RP) between the anterior and the posterior borders of ramus of Class III Group was shorter than that of Class I Group in men and women(p<0.01). Longer the distance(SN-AN) between the sigmoid notch and the antegonial notch was, longer the vertical ramal length above occlusal plane, higher the location of mandibular lingula, and shorter the antero-posterior ramal length were observed(p<0.01). Height of ramal bone marrow of Class III Group was higher than that of Class I Group in men and women(p<0.01). Distance between mandibular canal and buccal cortex of Class III Group in 1st and 2nd lower molars was shorter than that of Class I Group in men and women (p<0.05 in 1st lower molar in men, p<0.01 in others). These results indicate that there are some anatomical differences between the normal occlusal patients and the mandibular prognathic patients, such as the anterior-posterior length of ramus, the height of ramal bone marrow, and the location of mandibular canal.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.3
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• pp.56-71
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• 2013

This study was carried out to investigate the construction background of multi-functional vacant grounds in the rear gardens of Kyeongbok Palace and Kyeongun Palace, by understanding the building history of multi-functional vacant ground during the Joseon Dynasty with a special reference to the places formed in the period of King Kojong. The multi-functional vacant grounds in the Palace were the important element from the political aspect of Joseon Dynasty, and became an infrastructure of a state - run organization. The vacant space between Kwangyeonlu(廣延樓) and Haeonjeong, the whole region of Yeolmujeong(閱武亭), Seochongdae(瑞蔥臺), and Chundangdae(春塘臺) were investigated as the multi-functional places, where the events were held for the royal family in the Changdeok Palace after the establishment of the Joseon Dynasty. Various events such as the archery competition, official examination and military training were held at the places. After the inauguration of King Kojong, Kyeongmudae(京武臺) was made in the process of the reconstruction of the Kyeongbok Palace. The Kyeonghee Palace was used as the off-palace rear garden after the year that King Kojong returned to the Kyeongun Palace. The characteristics of two spaces were to apply the space organization of the Changdeok Palace into the rear garden outside of Sinmumun(神武門), Kyeongmudae at Kyeongbok Palace and the pedestrian overpass was established to connect the spaces efficiently in Kyeonghee Palace. Especially, the multi-functional vacant ground in the rear garden during the period of King Kojong functioned as the place to show off the internal and external independence of a nation and to show the authority and dignity of King at the point of time that accelerated the plundering Joseon Dynasty by Japanese imperialism powers, beyond the meaning of national event space that had existed before, such as official examination or archery test. In addition, the fact that the multi-functional vacant ground used as training place for military exercise where many people were mobilized was considered to reflect the contemporary situation.

• Restorative Dentistry and Endodontics
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• v.33 no.1
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• pp.1-8
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• 2008

The purpose of this study was to evaluate the effect of a new resin monomer, filler size and polishing technique on the surface roughness of composite resin restorations using confocal laser scanning microscopy. By adding new methoxylated Bis-GMA (Bis-M-GMA, 2,2-bis[4-(2-methoxy-3-methacryloyloxy propoxy) phenyl] propane) having low viscosity, the content of TEGDMA might be decreased. Three experimental composite resins were made: EX1 (Bis-M-GMA/TEGDMA = 95/5 wt%, 40 nm nanofillers); EX2 (Bis-M-GMA/TEGDMA = 95/5 wt%, 20 nm nanofillers); EX3 (Bis-GMA/TEGDMA = 70/30 wt%, 40 nm nanofillers). Filtek Z250 was used as a reference. Nine specimens (6 mm in diameter and 2 mm in thickness) for each experimental composite resin and Filtek Z250 were fabricated in a teflon mold and assigned to three groups. In Mylar strip group, specimens were left undisturbed. In Sof-lex group, specimens were ground with #1000 SiC paper and polished with Sof-lex discs. In DiaPolisher group, specimens were ground with #1000 SiC paper and polished with DiaPolisher polishing points. The Ra (Average roughness), Rq (Root mean square roughness), Rv (Valley roughness), Rp (Peak roughness), Rc (2D roughness) and Sc (3D roughness) values were determined using confocal laser scanning microscopy. The data were statistically analyzed by Two-way ANOVA and Tukey multiple comparisons test (p = 0.05). The type of composite resin and polishing technique significantly affected the surface roughness of the composite resin restorations (p < 0.001). EX3 showed the smoothest surface compared to the other composite resins (p < 0.05). Mylar strip resulted in smoother surface than other polishing techniques (p < 0.05). Bis-M-GMA. a new resin monomer having low viscosity, might reduce the amount of diluent, but showed adverse effect on the surface roughness of composite resin restorations.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.2
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• pp.71-79
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• 2017

Purpose: Ni-Cr alloy does not contain Beryllium, causing the metal compound to form oxides in the furnace but by using Titanium as a chemical catalyst the forming of the oxides can be controlled, and by controlling the impurities formed on the metal surface, the possibility of the Ni-Cr alloy bond strength being increased can be analysed. Materials and Methods: Titanium was used as a chemical catalyst in the porcelain for the oxidation of beryllium-free metal (Ni-Cr) alloy. The T1 group, which does not use Titanium power as a chemical catalyst is a reference model for comparison. The T2 group and T3 group used 10 g and 20 g of Titanium power, respectively. They are fabricated to observe the shear bond strength and surface properties. There was no significance when One-way ANOVA analysis/Tukey Honestly Significant Difference Test was conducted for statistical analysis among groups (P > 0.05). Results: Results of measuring the three-point flexural bond strength of the Ni-Cr alloy and thickness of the oxide film. Experiment T3 using 20 g Titanium chemical catalyst: $39.22{\pm}3.41MPa$ and $6.66{\mu}m$, having the highest bond strength and thinness of oxide film. Experiment T2 using 10 g Titanium chemical catalyst: $34.65{\pm}1.39MPa$ and $13.22{\mu}m$. Experiment T1 using no Titanium chemical catalyst: $32.37{\pm}1.91MPa$ and $22.22{\mu}m$. Conclusion: The T2 and T3 experiments using Titanium chemical catalyst showed higher bond strength for the Ni-Cr alloy and lower thickness of oxide film than experiment T1, and the titanium catalyst being able to increase bond strength was observed.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.2
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• pp.3-40
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• 2020

The term "accident" in the Warsaw Convention of 1929 and the Montreal Convention of 1999, which govern carrier liability in international air transport, is an important criterion for determining carrier liability. However, because there is no explicit definition of the term in the treaty provisions, the term is largely subjected to the judgment and interpretation of the courts. Although there have been numerous changes in purpose and circumstance in the transition from the Warsaw regime to the conclusion of the Montreal Convention, there was no discussion on the concept of "accident" therefore, even after the adoption of the Montreal Convention, there is no doubt that the term is to be interpreted in the same manner as before. On this point, the United States Supreme Court's Air France v. Saks clarified the concept of "accident" and is still cited as an important precedent. Recently, the CJEU, in GN v. ZU, presented a new concept of "accident" introduced in the Montreal Convention: that "reference must be made to the ordinary meaning" in interpreting "accident" and that the term "covers all situations occurring on aboard an aircraft." Furthermore, the CJEU ruled that the term does not include the applicability of "hazards typically associated with aviation," which was controversial in previous cases. Such an interpretation can be reasonably seen as the court's expansion of the concept of "accident," with a focus on "protecting consumer interests," a core tenet of both the Montreal convention and the European Union Regulations(EC: No 889/2002). The CJEU's independent interpretation of "accident" is a departure from the Warsaw Convention and the Saks case, with their focus on "carrier protection," and instead focuses on the "passenger protection" standard of the Montreal Convention. Consequently, this expands both the court's discretion and the carrier's risk management liability. Such an interpretation by the CJEU can be said to be in line with the purpose of the Montreal Convention in terms of "passenger protection." However, there are problems to be considered in tandem with an expanded interpretation of "accident." First, there may be controversy concerning "balance" in that it focused on "passenger protection" in relation to the "equitable balance of interests" between air carriers and passengers, which is the basic purpose of the agreement. Second, huge losses are expected as many airlines fly to countries within the European Union. Third, there is now a gap in the interpretation of "accident" in Europe and the United States, which raises a question on the "unity of rules," another basic tenet of the Convention. Fourth, this interpretation of "accident" by the CJEU raises questions regarding its scope of application, as it only refers to the "hazards typically associated with aviation" and "situations occurring aboard an aircraft." In this case, the CJEU newly proposed a novel criterion for the interpretation of "accident" under the Montreal Convention. As this presents food for thought on the interpretation of "accident," it is necessary to pay close attention to any changes in court rulings in the future. In addition, it suggests that active measures be taken for passenger safety by recognizing air carriers' unlimited liability and conducting systematic reforms.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.352-359
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• 2005

Uncertainty involved during determination of vitamin C content in infant formula was quantified by indophenol titration method. Uncertainty sources in measurand, such as purity, weight, final volume of standard, volume of standard solution used for titration, sample weight, final volume of sample, extraction solution used for titration, titration of extraction solution and standard solution by indophenol solution were identified and used as parameters for combined standard uncertainty based on Guide to the expression of uncertainty in measurement (GUM) and Draft EURACHEM/CITAC Guide. Uncertainty parameters of each source in measurand were identified as resolution, reproducibility and stability of chemical balance, standard material purity, repeatability, reproducibility, end point of titration, 1 mL pipet, 5 mL autopipet, and 100 mL mass flask. Each uncertainty component was evaluated by types A and B and included to calculate combined uncertainty. Analytical test result for traceability under laboratorial conditions using Certified Reference Material (CRM) test was certified as $108.4{\pm}1.7mg/100g$, which was within CRM certification range of $114.6{\pm}6.6mg/100g$. Uncertainty test result of vitamin C content of 5 g sampling was $56.7{\pm}2.44mg/100g$. Uncertainty could be reduced by identification of uncertainty sources and components related with vitamin C determination by indophenol titration method and by decreasing uncertainty sources and components.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.38-43
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• 2012

Purpose: Patients injected with FDG use the bathroom that Measured surface contamination level and spatial dose rate. This study about the effect that result affects workers in same part. Materials and Methods: Group1 is St. Vincent' s hospital's 60case. Group 2 is Bucheon St. Mary's hospital's 50case. Last case is lower the average daily number of patients than group 2. Measured time is 8:00, 10:00, 13:00, 15:00 and 17:00. Measured part is 4 point of toilet, basin and wastepaper basket, also measured accumulation dose of toilet during 3 month. Hospitals is installed PET/CT ware surveyed on presence of bathroom that used only by patient and worker has been using the bathroom. Results: The highest average surface contamination level of toilet is group1($8.38{\pm}4.56$), but the highest spatial dose rate is group3. Cumulative exposure dose measured by TLD during 3months is St.Vincent's hospital 0.78 mSv and Bucheon St.Mary's hospital 0.37 mSv. And result of survey is 16.12% worker using the bathroom. Conclusions: The more daily number of patient, the higher surface contamination level of bathroom. Especially, wastepaper basket's surface contamination level is exceed the reference value $4Bq/cm^2$. Based on This survey, Bathroom require special attention and proper decontamination.

• Childhood Kidney Diseases
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• v.4 no.1
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• pp.6-10
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• 2000

Purpose: To evaluate whether the urinary creatinine concentration is a reliable reference value to standardize urinary solute excretion in a spot urine sample during the first week of life. Methods: Spontaneously voided urine specimens were obtained in 49 healthy full term neonates, and in 33 healthy older children with the median ages of $5.7{\pm}4.3$ years, two urine samples were available with an interval of 2 to 3 days. Urine creatinine concentration was determined by the Jaffe test(CoBAS, Integra, Roche, Swiss). Uurine osmolality was determined by the freezing point depression test(Multi-osmette, Precision, USA). Results: Mean urinary creatinine and osmolality values of the first urine samples were not significantly different with the second urine samples in each group. Mean urinary creatinine and osmolality values in neonates were significantly different from the older children of the each urine sample(P<0.01). In neonates, the mean of the urinary oreatinine/osmolality ratios was higher than that of the older children(P<0.01). The urinary creatinine and the creatinine/osmolality values of the first urine samples were closely correlated with those of the second samples in both two groups(P<0.001). Conclusion: The urinary creatinine concentration during the first day of life is relatively stable, even when corrected for urinary osmolality The urinary creatinine and the urinary creatinine/osmolality ratio, therefore, can be used to standardize the urinary excretion of solutes in the neonate.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.4
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• pp.181-190
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• 2008

To response climate change and Kyoto protocol and to reduce greenhouse gas emissions, marine geological storage of $CO_2$ is regarded as one of the most promising option. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources(eg. power plant), to transport to the storage sites and to store $CO_2$ into the marine geological structure such as deep sea saline aquifer. To design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. The purpose of this paper is to compare and analyse the relevant equations of state including ideal, BWRS, PR, PRBM and SRK equation of state. To evaluate the predictive accuracy of the equation of the state, we compared numerical calculation results with reference experimental data. Ideal and SRK equation of state did not predict the density behavior above $29.85^{\circ}C$, 60 bar. Especially, they showed maximum 100% error in supercritical state. BWRS equation of state did not predict the density behavior between $60{\sim}80\;bar$ and near critical temperature. On the other hand, PR and PRBM equation of state showed good predictive capability in supercritical state. Since the thermodynamic conditions of $CO_2$ reservoir sites correspond to supercritical state(above $31.1^{\circ}C$ and 73.9 bar), we conclude that it is recommended to use PR and PRBM equation of state in designing of $CO_2$ marine geological storage process.