• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.141-147
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• 2005

Purpose: The most important thing in curing Malignant melanoma is surgical excision, operating method is wide excision. The author et al. studied 5-year survival rate of each stage and appropriate surgical margin after operating wide excision and immuno-chemotherapy. Materials and methods: From March 1995 to August 2003, wide excision and immunochemotherapy were operated to 35 patients (17 males and 18 females) who were diagnosed as malignant melanoma and followed up. Excision was done around 2 cm from edge of tumor regardless of the size or effected degree of the skin, and flap or full thickness skin graft was used for skin deficit that was not covered after excision. As for immuno-chemotherapy, method that prescribes 400 mg of dacarbazine (DTIC) and 3 million IU of interferone-${\alpha}$ in combination was used. Immuno-chemotherapy was operated to patients in over stage III. We used AJCC stage that was revised in 2002. Local recurrence, local metastasis and distant metastasis were investigated for these patients as well as the 5-year survival rate of each stage. Results: Most frequently 15 cases(42.8%) occurred in foot, 5 cases(14.2%) occured in ankle, 2 cases(5.7%) in leg, 2 cases(5.7%) in thigh and 5 cases(14.2%) in hand. The incidence of each stage were 8 cases(22.8%) in IA, 9 cases(25.7 %) in IB, 4 cases(11.4%) in IIA, 2 cases(5.7%) in IIB, 1 cases(2.8%) in IIIA, 2 cases(5.7%) in IIIB, 2 cases(5.7%) in IIIC and 7 cases(20.0%) in stage IV. 5-year survival rate of each stage were 94.1% in stage I, 66.8% in stage II, 40% in stage III and 14.3% in stage IV. Conclusion: 5-year survival rate of stage IV was low in malignant melanoma. In treatment of malignant melanoma, staging before operation is important as operation methods are different from each stage. We recommend wide excision which remove around 1~3 cm from margin of tumor up to each thickness.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.3
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• pp.231-242
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• 2008

Purpose: The purpose of this study was to investigate the bond strength of the core-veneer interface in all ceramic systems. Material and Methods: The all ceramic systems tested with their respective veneer were IPS Empress 2 with IPS Eris, IPS e.max Press with IPS e.max Ceram and IPS-e.max ZirCAD with IPS e.max Ceram. Cores (N=36, N=12/group, diameter: 10mm, thickness: 3mm) were fabricated according to the manufacturer's instruction and cleaned with ultrasonic cleaner. The veneer(diameter: 3mm, thickness: 2mm) were condensed in stainless steel mold and fired on to the core materials. After firing, they were again ultrasonically cleaned and embedded in acrylic resin. The specimens were stored in distilled water at $37^{\circ}C$ for 1 week. The specimens were placed in a mounting jig and subjected to shear force in a universal testing machine(Z020, Zwick, Germany). Load was applied at close to the core-veneer interface as possible with crosshead speed of 1.00mm/min until failure. Average shear bond strengths(MPa) were analyzed with a one-way analysis of variance and the Tukey test(${\alpha}=.05$). The failed specimens were examinated by scanning electron microscopy(JSM-6360, JEOL, Japan). The pattern of failure was classified as cohesive in core, cohesive in veneer, mixed or adhesive. Results: The mean shear bond strength($MPa{\pm}SD$) were IPS e.max Press $32.85{\pm}6.75MPa$, IPS Empress 2 $29.30{\pm}6.51MPa$, IPS e.max ZirCAD $28.10{\pm}4.28MPa$. IPS Empress 2, IPS e.max Press, IPS e.max ZirCAD were not significantly different from each others. Scanning electron microscopy examination revealed that adhesive failure did not occur in any all ceramic systems. IPS Empress 2 and IPS e.max Press exhibited cohesive failure in both the core and the veneer. IPS e.max ZirCAD exhibited cohesive failure in veneer and mixed failure.

• Journal of the Korean Society of Radiology
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• v.82 no.1
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• pp.128-138
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• 2021

Purpose We evaluated the risk factors for progression to chronic complicated bronchopleural fistula (BPF) after pulmonary resection using follow-up CT. Materials and Methods We retrospectively reviewed 45 cases with BPF that had undergone pulmonary resection during 2010-2018. We compared the clinical and radiological characteristics of those with complicated BPF (n = 24) and those without complicated (sterilized) BPF (n = 21). The clinical and radiological risk factors for progression to chronic complicated BPF were examined by logistic regression analysis. Results The thickness of the pleural cavity wall (p = 0.022), the size of the pleural cavity (p = 0.029), and the size increase of BPF on follow-up (p = 0.012) were significantly different between the two groups. The risk factors for progression to chronic complicated BPF were age > 70 years (odds ratio, 6.43; 95% confidence interval, 1.2-33.7), the thickness of the cavity wall > 5 mm (odds ratio, 52.5; 95% confidence interval, 5.1-545.4), and an increase in the size of the pleural cavity on follow-up CT (odds ratio, 12.5; 95% confidence interval, 2.1-73.5), only in the univariate analysis. Conclusion The risk factors for progression to chronic complicated BPF can be evaluated using follow-up CT.

• Investigative Magnetic Resonance Imaging
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• v.8 no.2
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• pp.100-108
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• 2004

Purpose : Early degeneration of articular cartilage is accompanied by a loss of glycosaminoglycan (GAG) and the consequent change of the integrity. The purpose of this study was to biochemically quantify the loss of GAG, and to evaluate the $Gd(DTPA)^{2-}$-enhanced, and T1, T2, rho relaxation map for detection of the early degeneration of cartilage. Materials and Methods : A cartilage-bone block in size of $8mm\;\times\;10mm$ was acquired from the patella in each of three pigs. Quantitative analysis of GAG of cartilage was performed at spectrophotometry by use of dimethylmethylene blue. Each of cartilage blocks was cultured in one of three different media: two different culture media (0.2 mg/ml trypsin solution, 1mM Gd $(DTPA)^{2-}$ mixed trypsin solution) and the control media (phosphate buffered saline (PBS)). The cartilage blocks were cultured for 5 hrs, during which MR images of the blocks were obtained at one hour interval (0 hr, 1 hr, 2 hr, 3 hr, 4 hr, 5 hr). And then, additional culture was done for 24 hrs and 48 hrs. Both T1-weighted image (TR/TE, 450/22 ms), and mixed-echo sequence (TR/TE, 760/21-168ms; 8 echoes) were obtained at all times using field of view 50 mm, slice thickness 2 mm, and matrix $256\times512$. The MRI data were analyzed with pixel-by-pixel comparisons. The cultured cartilage-bone blocks were microscopically observed using hematoxylin & eosin, toluidine blue, alcian blue, and trichrome stains. Results : At quantitation analysis, GAG concentration in the culture solutions was proportional to the culture durations. The T1-signal of the cartilage-bone block cultured in the $Gd(DTPA)^{2-}$ mixed solution was significantly higher ($42\%$ in average, p<0.05) than that of the cartilage-bone block cultured in the trypsin solution alone. The T1, T2, rho relaxation times of cultured tissue were not significantly correlated with culture duration (p>0.05). However the focal increase in T1 relaxation time at superficial and transitional layers of cartilage was seen in $Gd(DTPA)^{2-}$ mixed culture. Toluidine blue and alcian blue stains revealed multiple defects in whole thickness of the cartilage cultured in trypsin media. Conclusion : The quantitative analysis showed gradual loss of GAG proportional to the culture duration. Microimagings of cartilage with $Gd(DTPA)^{2-}$-enhancement, relaxation maps were available by pixel size of $97.9\times195\;{\mu}m$. Loss of GAG over time better demonstrated with $Gd(DTPA)^{2-}$-enhanced images than with T1, T2, rho relaxation maps. Therefore $Gd(DTPA)^{2-}$-enhanced T1-weighted image is superior for detection of early degeneration of cartilage.

• Nuclear Engineering and Technology
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• v.39 no.5
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• pp.603-616
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• 2007

Roy Huddle, having invented the coated particle in Harwell 1957, stated in the early 1970s that we know now everything about particles and coatings and should be going over to deal with other problems. This was on the occasion of the Dragon fuel performance information meeting London 1973: How wrong a genius be! It took until 1978 that really good particles were made in Germany, then during the Japanese HTTR production in the 1990s and finally the Chinese 2000-2001 campaign for HTR-10. Here, we present a review of history and present status. Today, good fuel is measured by different standards from the seventies: where $9*10^{-4}$ initial free heavy metal fraction was typical for early AVR carbide fuel and $3*10^{-4}$ initial free heavy metal fraction was acceptable for oxide fuel in THTR, we insist on values more than an order of magnitude below this value today. Half a percent of particle failure at the end-of-irradiation, another ancient standard, is not even acceptable today, even for the most severe accidents. While legislation and licensing has not changed, one of the reasons we insist on these improvements is the preference for passive systems rather than active controls of earlier times. After renewed HTGR interest, we are reporting about the start of new or reactivated coated particle work in several parts of the world, considering the aspects of designs/ traditional and new materials, manufacturing technologies/ quality control quality assurance, irradiation and accident performance, modeling and performance predictions, and fuel cycle aspects and spent fuel treatment. In very general terms, the coated particle should be strong, reliable, retentive, and affordable. These properties have to be quantified and will be eventually optimized for a specific application system. Results obtained so far indicate that the same particle can be used for steam cycle applications with $700-750^{\circ}C$ helium coolant gas exit, for gas turbine applications at $850-900^{\circ}C$ and for process heat/hydrogen generation applications with $950^{\circ}C$ outlet temperatures. There is a clear set of standards for modem high quality fuel in terms of low levels of heavy metal contamination, manufacture-induced particle defects during fuel body and fuel element making, irradiation/accident induced particle failures and limits on fission product release from intact particles. While gas-cooled reactor design is still open-ended with blocks for the prismatic and spherical fuel elements for the pebble-bed design, there is near worldwide agreement on high quality fuel: a $500{\mu}m$ diameter $UO_2$ kernel of 10% enrichment is surrounded by a $100{\mu}m$ thick sacrificial buffer layer to be followed by a dense inner pyrocarbon layer, a high quality silicon carbide layer of $35{\mu}m$ thickness and theoretical density and another outer pyrocarbon layer. Good performance has been demonstrated both under operational and under accident conditions, i.e. to 10% FIMA and maximum $1600^{\circ}C$ afterwards. And it is the wide-ranging demonstration experience that makes this particle superior. Recommendations are made for further work: 1. Generation of data for presently manufactured materials, e.g. SiC strength and strength distribution, PyC creep and shrinkage and many more material data sets. 2. Renewed start of irradiation and accident testing of modem coated particle fuel. 3. Analysis of existing and newly created data with a view to demonstrate satisfactory performance at burnups beyond 10% FIMA and complete fission product retention even in accidents that go beyond $1600^{\circ}C$ for a short period of time. This work should proceed at both national and international level.

• Journal of Animal Science and Technology
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• v.55 no.1
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• pp.67-74
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• 2013

To know the emission amount of greenhouse gases from bedding materials of cowshed floor, the emission rates of methane ($CH_4$) and nitrous oxide ($N_2O$) gases from a simulated cowshed floor (SCF) with sawdust that manure loading rate into the bedding material could be accurately controlled were assessed in this study. The manure loading rates of Korean beef and Holstein dairy cattle into the SCF of $0.258m^2$ surface area with 10 to 15 cm height sawdust were $1.586kg/m^2/d$ and $3.588kg/m^2/d$, respectively, and those were calculated on the basis of "Standard model for sustainable livestock" and "Data for excretion amount of manure from livestock". All experiments were done in triplicates in three different seasons (May to July, Sep. to Nov., and Feb. to Apr.) using 12 SCFs. The effects of bedding material thickness on $CH_4$ and $N_2O$ emission from SCFs for both Korean beef cattle and Holstein dairy cattle were not statistically significant (p<0.05). Emission amount of $CH_4$ and $N_2O$ per square meter of SCF for Holstein dairy cattle was 7.5 and 1.2 times higher than that of Korean beef cattle, respectively. The yearly $CH_4$ amount per head was 17.7 times higher in Holstein dairy cattle, obtaining 130.4 g/head/year from SCF for Holstein dairy cattle and 7.4 g/head/year from SCF for Korean beef cattle, and $N_2O$ was also 3.8 times higher in Holstein dairy cattle (3,267 g/head/year in Korean beef cattle and 14,719 g/head/year in Holstein dairy cattle). However, the $N_2O$-N per loaded nitrogen into SCF was higher in Korean beef cattle, having 0.2148 and 0.1632 kg $N_2O$-N/kg N in Korean beef cattle and Holstein dairy cattle, respectively, and those values were 3.07 and 2.33 times higher than that of Intergovernmental Panel on Climate Change (IPCC) 2006 guideline (GL) (0.07 kg $N_2O$-N/kg N).

• Journal of the Korean Vacuum Society
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• v.15 no.1
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• pp.97-102
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• 2006

Anodic alumina with self-organized and ordered nano hole arrays can be a good candidate of an irradiation mask to modify the properties of nano-scale region. In order to try using porous anodic alumina as a mask for ion-beam patterning, ion beam transmittance of anodic alumina was tested. 4 Um thick self-standing AAO templates anodized from Al bulk foil with two different aspect ratio, 200:1 and 100:1, were aligned about incident ion beam with finely controllable goniometer. At the best alignment, the transmittance of the AAO with aspect ratio of 200:1 and 100:1 were $10^{-8}\;and\;10^{-4}$, respectively. However transmittance of the thin film AAO with low aspect ratio, 5:1, were remarkably improved to 0.67. The ion beam transmittance of self-standing porous alumina with a thickness larger than $4{\mu}m$ is extremely low owing to high aspect ratio of nano hole and charging effect, even at a precise beam alignment to the direction of nano hole. $SiO_2$ nano dot array was formed by ion irradiation into thin film AAO on $SiO_2$ film. This was confirmed by scanning electron microscopy that the $SiO_2$ nano dot array is similar to AAO hole array.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.1
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• pp.61-66
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• 2012

Chemical Mechanical Planarization (CMP) is a polishing process used in the microelectronic fabrication industries to achieve a globally planar wafer surface for the manufacturing of integrated circuits. Pad conditioning plays an important role in the CMP process to maintain a material removal rate (MRR) and its uniformity. For metal CMP process, highly acidic slurry containing strong oxidizer is being used. It would affect the conditioner surface which normally made of metal such as Nickel and its alloy. If conditioner surface is corroded, diamonds on the conditioner surface would be fallen out from the surface. Because of this phenomenon, not only life time of conditioners is decreased, but also more scratches are generated. To protect the conditioners from corrosion, thin organic film deposition on the metal surface is suggested without requiring current conditioner manufacturing process. To prepare the anti-corrosion film on metal conditioner surface, vapor SAM (self-assembled monolayer) and FC (Fluorocarbon) -CVD (SRN-504, Sorona, Korea) films were prepared on both nickel and nickel alloy surfaces. Vapor SAM method was used for SAM deposition using both Dodecanethiol (DT) and Perfluoroctyltrichloro silane (FOTS). FC films were prepared in different thickness of 10 nm, 50 nm and 100 nm on conditioner surfaces. Electrochemical analysis such as potentiodynamic polarization and impedance, and contact angle measurements were carried out to evaluate the coating characteristics. Impedance data was analyzed by an electrical equivalent circuit model. The observed contact angle is higher than 90o after thin film deposition, which confirms that the coatings deposited on the surfaces are densely packed. The results of potentiodynamic polarization and the impedance show that modified surfaces have better performance than bare metal surfaces which could be applied to increase the life time and reliability of conditioner during W CMP.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.138-164
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• 2022

The Neolithic shell midden in Daejuk-ri, Seosan, is distributed on the gentle slope of a low hill close to the west coast. The bedrock of the area consists mainly of schist with various mafic minerals, but shows a partial gneiss pattern. The site consists of loamy topsoil and clay loam subsoil, and the degree of siallization is relatively low. Although the pottery excavated from the shell midden shares mostly similar features, a variety of shapes and patterns coexist. The surface colors, thickness and physical properties are slightly different. The pottery can be subdivided into three types (IA, IB and II) according to the composition of the body clay, the temper and the existence of a black core. Types IA and IB are colorless mineral pottery with a non-black or black core respectively. TypeII is colored mineral pottery with a non-black core. Type I pottery also contains non-plastic colored minerals, but type II contains a large amount of biotite, chlorite, talc, amphibole, diopside and tremolite, which include a large amount of Mg and Fe. The studied pottery contains a small amount of organic matter. Considering the grain size and relatively poor sorting and roundness of the non-plastic particles, the pottery appears to be made by adding coarse non-plastic tempers for special purposes to the untreated weathered soil around the site. The three types of pottery seem to have been incompletely fired in general. While type IB has the lowest degree of oxidation, typeII shows the highest degree of redness and oxidation. It can be interpreted that these differences depend on the firing temperature and the ratio of non-plastic particles. Through a synthesis of the minerals, geochemical data and thermal history, it can be determined that the firing temperature ranged from 600 to 700℃. The pottery types of the Daejuk-ri Shell Midden have slightly different production conditions, mineral compositions, and physical properties, but have undergone similar production processes with basically the same clay materials. The clay is almost identical to the composition of the bedrock and weathered soil distributed in the Daejuk-ri area. Currently, there is an industrial complex in the area, so it is difficult to confirm the soil and geological distribution of the site. However, it is highly probable that the area around the site was self-sufficient for the clay and tempers required for the production of the Neolithic pottery. Therefore, it can be interpreted that the group that left the shell midden in Daejuk-ri lived near the site, visited the site for the purpose of collecting and processing shellfish, and discarded the broken pottery along with shells.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.1
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• pp.37-43
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• 2008

Purpose: To evaluate dosimetry results of three different techniques for whole breast irradiation after conservative surgery of large pendulous breast patient. Materials and Methods: Planning computed tomography (CT) scans for three techniques were performed on a GE Hi-speed advantage CT scanner in the supine (SP), supine with breast supporting Device (SD) and prone position on a custom prone mattress (PP). Computed tomography images were acquired at 5 mm thickness. The clinical target volumes (CTV), ipsilateral lung and heart were delineated to evaluate the dose statistic, and all techniques were planned with the tangential photon beams (Pinnacle$^3$, Philips Medical System, USA). The prescribed dose was 50 Gy delivered in 25 fractions. To evaluate the dose coverage for CTV, we analysed percent volume of CTV receiving minimum of 95%, 100%, 105%, and 110% of prescription dose ($V_{95}$, $V_{100}$, $V_{105}$, and $V_{110}$) and minimal dose covering 95% ($D_{95}$) of CTV. The dosimetric comparison for heart and ipsilateral lung was analysed using the minimal dose covering 5% of each organs ($D_5$) and the volume that received >18 Gy for the heart and >20 Gy for the ipsilateral lung. Results: Target volume coverage ($V_{95}$ and $V_{100}$) was not significantly different for all technique. The V105 was lower for PP (1.2% vs. 4.4% for SP, 11.1% for SD). Minimal dose covering 95% ($D_{95}$) of target was 47.5 Gy, 47.7 Gy and 48 Gy for SP, SD and PP. The volume of ipsilateral lung received >20 Gy was 21.7%, 11.6% and 4.9% for SP, SD and PP. The volume of heart received >18 Gy was 17.0%, 16.1% and 9.8% for SP, SD and PP. Conclusion: Prone positioning of patient for large pendulous breast irradiation enables improving dose uniformity with minimal heart and lung doses.