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Indium tin oxide (ITO) films with various oxygen partial pressure from 0 to 6 × 10 Pa were prepared onto polyethylene terephthalate (PET) using RF magnetron sputtering at room temperature. The structural, electrical and optical properties of the grown ITO films were investigated as a function of the oxygen partial pressure. The amorphous nature of the ITO films was dominant at the partial pressure below 1 × 10 Pa and the degree of crystallinity increased as the oxygen concentration increased further. This structural change comes with the increased carrier concentration and reduction of the electrical resistivity down to 9.8 × 10 Ω · cm. The average transmittance (at 400~800 nm) of the ITO deposited on the PET substrates increased as the oxygen partial pressure increased and transmittance above 80 % was achieved with the partial pressure of 4 × 10 Pa. The results show that the choice of optimal oxygen partial pressure can present improved film crystallinity, the increased carrier concentration, and the enhancement in the electrical conductivity.

High density plasma etching of ultrananocrystalline diamond (UNCD) films wasperformed in O2 and O2/Ar inductively coupled plasma (ICP) discharges. The O2/Ar ICP discharges produced higher etch rates due to enhanced physical component of the etching, and a maximum etch rate of -280 nm/min was obtained in 10 sccm O2/5 sccm Ar discharges. Very high etch selectivities up to -140:1 were obtained for the UNCD over Al mask layer. Anisotropic pattern transfer with a vertical sidewall profile was achieved in the 10 sccm O2/5 sccm Ar discharges at a relatively low source power (300 W) and a moderate rf chuck power (200 W).

In this study, we report the synthesis and characterization of novel hybrid nanocoating based on carbon nanotubes (CNTs) on anodized aluminum surfaces (AAO). The hybrid nanocoating was deposited by number of methods which include spray coating, spin coating and dip coating. The bonding of nanocoating with metal surface is an important parameter for successful modification of the metal surfaces. The improved adhesion of nanocoating on metal surfaces could be attributed to chemical bonding of sol-gel nanocoating with anodized surfaces. The nanocoated anodized aluminum surfaces showed superior adhesion and excellent anticorrosive properties. The nanocoated panels showed enhanced galvanic protection comparable to 80% of titanium metal as determined by galvanic corrosion measurements. It also showed higher thermal conductivities than stainless steel and bare anodized surfaces.

A significant improvement in surface morphology of ultrananocrystalline diamond (UNCD) film was achieved with hydrogen heat treatment of nanodiamond (ND) seed particles. By hydrogen heat treatment, the average size of ND aggregates was greatly reduced from ∼2 µm to ∼55 nm as the ND surfaces were modified to hydrogen-containing functionalities. Si surfaces seeded with the hydrogen heat-treated ND seeds showed very high seeds densities up to ∼1011 cm−2. The grown UNCD film with ND seeds treated at 600 °C provided a very smooth surface morphology consisted of small and uniformly distributed grains compared to the film grown with untreated ND seeds. AFM scan image of the grown UNCD films seeded with untreated and hydrogen heat-treated ND particles.

Diamond-like carbon (DLC) coatings of 300, 500 and 650 nm thickness were deposited on stainless steel substrates using a filtered cathodic vacuum arc hybrid with magnetron sputtering system. A 100 nm thick chromium interlayer was deposited before the deposition of the DLC coatings. The films morphology was characterised by field emission scanning electron microscopy and structure was identified by Raman spectroscopy. Tribology was evaluated by ball disc wear test and wear tracks were observed by scanning electron microscopy. The interface adhesion was studied by scratch tester. The results of all characterisations were concluded and 500 nm DLC coating has suggested as optimum thickness that would be applicable for industrial applications.

Poly vinylidene fluoride-co-hexafluoropropylene (PVdF-HFP) membrane were prepared by the electrospinning technique. We had applied a DLC coating process and then the surface of the membrane and the contact angle change was investigated. Electrospun fibrous PVdF-HFP membrane surface became to wrinkled shape by Ar plasma treatment and treatment conditions. The wrinkled surface of PVdF-HFP membrane became super-hydrophilic. However, after DLC coating process, it became super-hydrophobic. The resulting surfaces were characterized by water contact angle measurement, X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM). Resultantly it was recognized that the wettability characteristics of the membrane surfaces depended on the chemical composition and surface morphology.

Diamond-like carbon (DLC) coatings are getting new trends for cutting tool applications. In this research work, the DLC coatings were deposited on 15 × 15 × 5-mm tungsten carbide cobalt substrates with variation of bias voltage from 0 to 500 V. The DLC films of 400 nm were deposited using filter cathode vacuum arc system, and 100-nm chromium interlayer was deposited by sputtering. The optimized conditions for plasma pretreatment at different argon flow rates and deposition rates with bias variation were found. The effect of bias voltage on microstructure, tribology, adhesion, and mechanical properties were evaluated. The characterization techniques employed were field emission electron microscopy, Raman spectroscopy, wear test, SEM, scratch test, and nano-indentation. The effect of substrate pretreatment on film adhesion was also evaluated. It was observed that etching rate increased with the increase in Ar flow rate while DLC deposition and sputtering rates decreased with increase in the bias voltage. The characterization suggests the DLC coatings deposited at 0 V bias as optimum condition because of showing the best results among all other conditions. Copyright © 2014 John Wiley & Sons, Ltd.

BDD is a substance which is generated by doping Diborane (B2H6) in CH4 and H2, and then synthesized with thin diamond film. It has good corrosion resistance, is physically and chemically stable, has a wide potential window, low electrical conductivity, good heat impact resistance and optimal hardness, so it is highlighted among electrodes. PbO2, an electrode previously used for generating ozone water, presents environmental problems since the structure of the electrodes is changed and aged due to the strong acidity of the ozone generated when these electrodes are employed for a long time, so it is considered to have short longevity. Moreover, Pb a heavy metal component, is eluted, etc. In contrast, BDD has recently been highlighted as an electrode that can be used for next-generation ozone water generation to solve these problems. Boron-doped diamond electrodes have excellent hardness, excellent physical properties. Chemical stability, and durability. In addition, BDD has a wide potential window and low current density characteristics, so application attention is focused. This study evaluated the ozone-generating characteristics of BDD electrodes generated in accordance with the doping concentration of boron. The BDD generated was examined by field emission scanning electron microscopy and Raman spectroscopy, and its electric characteristics were determined by Hall measurements. The amount of ozone generated at the boron doping concentration was compared using an ozone generating kit. Figure 1

The malignant transformation of Warthin’s tumor in the parotid gland is extremely rare. In addition, among the various types of the malignant change of Warthin’s tumor, squamous cell carcinoma is the rarest one. The pathogenesis of this rare disease entity is uncertain till now. Also the most effective treatment and long-term prognosis are not yet clear. Up to present, there are a few reports that only described the pathologic and clinical features of this tumor. However, there is no report about the imaging findings of this rare tumor. We report the imaging features in a case of squamous cell carcinoma arising from Warthin’s tumor in the parotid gland.

The purpose of this study is to examine the low-cycle fatigue (LCF) characteristics of high-chrome heat-resistant steel, which is used in a high-temperature environment, at both ambient and high temperature. High-chrome heat-resistant steel, which is used for the turbine blades of a nuclear power plant, can be subject to plastic deformation due to overloading conditions at startup and shutdown. It is therefore very important to evaluate the damage caused by LCF, which is considered as fatigue damage due to plastic deformation. To examine the mechanical properties of high-chrome heat-resistant steel, the tensile strength was tested under different heat treatment conditions. In addition, the LCF characteristics were tested at ambient temperature and [Formula: see text].

Sulzer-type engines are widely used in ships given their excellent fuel-saving, low-noise, and low-vibration properties. Here, we evaluated the low-cycle fatigue (LCF) properties of SNCM 420H steel after heat-tempering. LCF was studied at both [Formula: see text] and [Formula: see text], at strains of 0.8, 0.9, 1.2 and 1.5%. We used a triangular waveform for LCF testing to find fracture. The fatigue life of SNCM 420H at [Formula: see text] was about 60% less than that at [Formula: see text].

4001 Background: Adjuvant chemotherapy and/or chemoradiotherapy have been the standard of care in GC for years, supported by randomized trials. We compared the efficacy of different chemotherapy regimens and chemoradiotherapy in patients with D2-resected, stage II/III, node-positive GC. Methods: From Feb 2013 through Nov 2018, we randomly assigned, in a 1:1:1 ratio, patients with pathologically-staged II or III, node-positive, D2-resected GC, to receive adjuvant S-1 (40-60 mg twice daily 4-weeks-on/2-weeks-off) for one year, S-1 (2-weeks-on/1-week-off) plus oxaliplatin 130 mg/m2 (SOX) for six months, or SOX plus chemoradiotherapy 45 Gy (SOXRT). Randomization was stratified according to the type of surgery (total or subtotal gastrectomy), stage (II or III), and Lauren histologic classification (diffuse or intestinal). The primary endpoint was disease-free survival (DFS). A total of 900 patients had to be enrolled to demonstrate superiority of SOX or SOXRT to S-1 (hazard ratio [HR] 0.667), with 90% power at a two-sided significance level of 5%. Results: A total of 538 patients were included for this interim efficacy analysis. Median age was 58 years, men constituted 65%, and stage II and III were 31% and 69%, respectively. Baseline tumor and patient characteristics were balanced between treatment arms. Adverse events were as anticipated in each arm, generally well-tolerated and manageable. DFS in the control arm (S-1) were significantly shorter than in SOX and SOXRT arms (stratified HR for recurrence): S-1 vs. SOX, 0.617 (P = 0.016) and S-1 vs. SOXRT, 0.686 (P = 0.057). The DFS at 3-years was found to be 65%, 78% and 73% in S-1, SOX and SOXRT arms, respectively. No difference in DFS between SOX and SOXRT was found (HR 0.910, P = 0.667). Based on the results after the observation of 145 recurrence events at the cutoff date of Dec 27, 2018, the independent data monitoring committee considered the results sufficient to meet the endpoint of the trial and recommended early stopping of the trial. Conclusions: In patients with curatively D2-resected, stage II/III, node-positive GC, adjuvant SOX or SOXRT was effective in prolonging DFS, when compared to S-1 monotherapy. Clinical trial information: NCT0176146.

Design and implementation of a low-loss K-band duplexer consisting of two narrow bandpass filters with low-impedance open-loop resonators (OLRs) is presented. Narrow bandpass filters of 4%-7% bandwidth were often implemented with OLRs, but previous designs used OLRs mostly with 50 Ω linewidth. The design process was complicated due to multiple coupling mechanisms and multiple spurious response frequencies, often resulting in excessive insertion loss, especially at higher center frequencies. With the proposed design procedure for OLR filters, the values of the low-impedance line (less than 50 Ω) and proper coupling spacing are determined in the process of optimizing the filter performance, resulting in low insertion loss up to above K-band frequencies. The size of the proposed filter is also reduced to 64% of the conventional OLR filters. As an example of the proposed design method, a duplexer consisting of 4% narrow bandpass filters centered at 18.7 GHz and 22.5 GHz was implemented and measured, and the maximum insertion loss in each passband was 1.2 dB, which is much less than those of the previous design approaches.

Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumor of the gastrointestinal tract that has both exocrine and neuroendocrine components. There are only 5 case reports about this combined tumor in the small bowel, arose in a background of long-standing Crohn’s disease. Here, we report a case of small bowel MANEC in a 54-year-old male with Crohn’s disease, who presented a heterogeneous enhancing, asymmetric small bowel wall thickening with small bowel obstruction and had a difficulty in differential diagnosis before surgery.

Extraskeletal Ewing’s sarcoma (EES) is a rare malignant soft tissue tumor which is morphologically indistinguishable from skeletal ES. EES usually occurs in young adults and children and there has been only one case reported in a patient aged over 70 years old. We report a case of an EES arising from the first thoracic spinal nerve root in a 73-year-old female, which was misdiagnosed as benign nerve sheath tumor in preoperative imaging evaluation.

The diamond like carbon coatings (DLC) of 400 nm thickness was deposited by filtered cathodic vacuum arc system. The argon plasma etched and non-etched tungsten carbidecobalt (WC-Co) and stainless steel (SUS) were used as substrates. The chromium was deposited as an interlayer for diamond like carbon coatings on the etched and non-etched WC-Co and SUS substrates. The present research is to evaluate the effect of argon plasma etching of the substrates on microstructure, tribology and adhesion strength of DLC coatings. The films were characterized by field emission scanning electron microscopy, Raman spectroscopy, tribology and scratch tests. The Raman studies showed the broad peak ∼1550 cm −1 indicates the formation of amorphous carbon or diamond-like carbon. It was found that the DLC coatings on the plasma etched substrates of WC-Co and SUS have shown the low friction coefficient of ∼0.12–0.14. The DLC coatings on plasma etched substrates of WC-Co have better adhesion strength. The results showed that the argon plasma etching of substrate reduces the surface roughness to ∼2.5 nm, resulting in smooth morphology, good adhesion and wear resistance as compared to DLC coating on non-etched substrates. The scanning electron microscopic studies showed that the DLC coated specimens with plasma etched substrates have minimum damage as compared to the DLC coated non etched substrates.

Aluminum oxide (Al 2 O 3 ) thin films were deposited on silicon (100) and quartz substrates by pulsed laser deposition (PLD) at an optimized oxygen partial pressure of 3.0×10 −3 mbar in the substrate temperatures range 300–973 K. The films were characterized by X-ray diffraction, transmission electron microscopy, atomic force microscopy, spectroscopic ellipsometry, UV–visible spectroscopy and nanoindentation. The X-ray diffraction studies showed that the films deposited at low substrate temperatures (300–673 K) were amorphous Al 2 O 3 , whereas those deposited at higher temperatures (≥773 K) were polycrystalline cubic γ -Al 2 O 3 . The transmission electron microscopy studies of the film prepared at 673 K, showed diffuse ring pattern indicating the amorphous nature of Al 2 O 3 . The surface morphology of the films was examined by atomic force microscopy showing dense and uniform nanostructures with increased surface roughness from 0.3 to 2.3 nm with increasing substrate temperature. The optical studies were carried out by ellipsometry in the energy range 1.5–5.5 eV and revealed that the refractive index increased from 1.69 to 1.75 ( λ =632.8 nm) with increasing substrate temperature. The UV–visible spectroscopy analysis indicated higher transmittance (>80%) for all the films. Nanoindentation studies revealed the hardness values of 20.8 and 24.7 GPa for the films prepared at 300 K and 973 K respectively.

SF6/O2 plasma surface texturing was employed to pretreat Si substrate for achieving enhanced diamond nucleation density. Surface roughness of the textured Si was found to be strongly dependent on the process pressure and normalized roughness values in the range of 2-16 were obtained. Remarkably enhanced nucleation densities of ~1010 cm-2 compared to conventional mechanical abrasion were obtained after seeding for the surface textured Si substrates. Raman spectroscopy revealed that ultrananocrystalline diamond films with grain size below 10 nm were grown on the surface textured Si.

Cerium oxide (CeO 2 ) thin films were deposited on Si (100) and glass substrates at various oxygen partial pressures (2×10 −5 mbar–3×10 −1 mbar) and a substrate temperature of 673 K, by pulsed laser deposition (PLD). The structural, morphological and optical properties of the films were characterized by X-ray diffraction, Raman spectroscopy, high resolution transmission electron microscopy, atomic force microscopy, photoluminescence and UV–visible spectroscopy. XRD analysis revealed the polycrystalline and cubic structure of the CeO 2 films with preferred orientation for (200) as the increase of oxygen partial pressure. The Raman studies indicated the formation of Ce–O with the systematic variation of peak intensity and FWHM with oxygen partial pressures. The high resolution transmission electron microscopy investigation confirmed the polycrystalline and cubic nature of the CeO 2 films with (200) preferred orientation. The AFM studies showed the roughness (RMS) values of the films increased from 0.8 nm to 4.6 nm with increasing oxygen partial pressure from 2×10 −5 mbar to 3×10 −1 mbar. The photoluminescence (PL) investigation indicated the bandgap values in the range 3.05–3.10 eV with increasing oxygen partial pressures. The UV–visible spectroscopy analysis demonstrated that the refractive index of the films decreased from 2.41 to 1.72 with increasing oxygen partial pressures.

It is well known that fatigue failure occur on welded structures in industrial application due to the repetitive load force. In order to decrease the fatigue failure, we analysed the mechanical properties based on their structural aspect, roll steel (SS 400) welded onto stainless steels (STS 304) by CO2 gas as well as structure roll steel welded onto itself. We compared the hardness, tensile and fatigue properties with two kinds of samples which had no defects on the welding part observed by X-ray topographic analysis. It was recognized that the tensile and fatigue strength of SS 400 welded onto itself by CO2 gas was higher than that of SS 400 welded onto STS 304.

Indium tin oxide (ITO) films with various thicknesses from 104 nm to 513 nm were prepared onto polyethylene terephthalate (PET) substrates by using r.f. magnetron sputtering without intentionally heating the substrates. The structural, optical, and electrical properties of ITO films were investigated as a function of film thickness. It was found that the amorphous nature of the ITO film was dominant below the thickness of about 200 nm but the degree of the crystallinity increased with an increasing thickness above the thickness of about 250 nm, resulting in the increase of carrier concentration and therefore reducing the electrical resistivity from 5.1 x 10(-3) to 9.4 x 10(-4) omega x cm. The average transmittance (400-800 nm) of the ITO deposited PET substrates decreased as the film thickness was increasing and was above 80% for the thickness below 315 nm. The results show that the improvement of the film crystallinity with the film thickness contributes to the increase of the carrier concentration and the enhancement of the electrical conductivity.

Very smooth ultrananocrystalline diamond (UNCD) film growth on SiC substrate was achieved by a novel pretreatment technique consisted of SiC surface texturing and deaggregation of nanodiamond (ND) seed particles. Texturing of SiC surfaces in Ar and SF6/02 plasmas was found to be able to provide normalized roughness values of 0.5-7.0 compared to the untreated surface. SiC surface plasma-textured and seeded with H2 heat-treated ND particles at 600 degrees C showed the highest nucleation density of ~44.2 x 10(11) cm(-2) and a highly uniform coverage of surface with very fine ND seeds. The UNCD film grown with this new pretreatment technique showed a very smooth surface morphology consisted of small and uniformly distributed grains.

Objectives: The purpose of this study is to investigate the comparison of 3DVH software and two-dimensional array systems (MatriXX, ArcCHECK, and portal dosimetry system) on pretreatment verification for volumetricmodulated arc therapy. Methods: Dosimetric measurements were performed using the verification for 20 treatment plans. Measured dosimetric differences were evaluated by gamma pass rate and percentage dose difference. Dose-volume histograms (DVHs) calculated by the treatment planning system were also compared with those predicted by the 3DVH software. Results: The mean gamma pass rates were more than 95% for the 3%/3 mm criterion, except for 3D evaluation using the 3DVH (3DVH (3D)) software in prostate cancer cases. In the cases of head-and-neck (HN) cancer, the mean gamma pass rates by ArcCHECK and 3DVH 2D evaluation (3DVH (2D)) were estimated to be lower than those of MatriXX, EPID, and 3DVH (3D) for the 2%/2 mm and 1%/1 mm criteria. The percentage dose differences were within 4% for all structures, and correlated with the mean gamma pass rate for the planning target volume (PTV) and the Dmean of the spinal cord (p < 0.05). On the other hand, the mean gamma pass rates of prostate cases presented similar results for all criteria. The percentage dose differences for structure volumes in the cases of prostate cancer (from 2.76% to 12.58%) were larger than those in the cases of HN cancer, and there was no statistical significance except for the Dmax of the bladder. Conclusion: Judging from our results, the three dosimetric devices showed similar results for pretreatment verification and portal dosimetry can be replaced as the verification system. However, the use of 3DVH software remains to be a matter for further discussion.

Transparent diamond-like carbon (DLC) films were synthesized on glass using radio frequency plasma enhanced chemical vapor deposition method from the gas mixture of , and Ar. The pressure, the rf-power, ratio, and the deposition time were 0.1Torr, 100W, 20 : 1 : 1, and 20 min, respectively. The optical transmittances of DLC-deposited glass and uncoated glass were compared with each other in the visible light regions. The DLC-deposited glass showed transmittance of approximately 83 % and 95 % as compared to the uncoated glass for the wavelength of 380 nm and 500 nm, respectively. The hardness and roughness of DLC-coated glass have been measured by nanoindentation and AFM, respectively. The DLC-coated glass showed a little less or similar optical transmittance compared to the uncoated glass, while the hardness of DLC-coated glass was 2.5 times higher than that of the uncoated glass. The deposited DLC film had the very smooth surface and was thicker than 150 nm after deposition for 20 min.

Several R&Ds are being performed for Korean helium cooled solid breeder (HCSB) test blanket module (TBM) in the field of hydrogen isotopes permeation characteristics measurement in the helium purge line, joining technologies of structural materials, breeder pebble materials development, and the measurement of pebble bed characteristics. Electron beam welding for reduced activated ferritic–martensitic (RAFM) steel is evaluated to find optimal welding conditions. Also, a hydrogen permeation measurement apparatus is newly installed for the evaluation of the permeation barrier characteristics of stainless steel and RAFM steels. Two fabrication methods of lithium orthosilicate pebbles are investigated using slurry droplet methods. As methods of silicon carbide coating on the graphite pebble, microwave coating and chemical vapor deposition coating are evaluated. Two apparatuses are established to assess the thermo-mechanical properties of graphite and breeder pebble beds. The current status of R&D activities on these areas is introduced and the main progresses are addressed in this paper.

Numerical simulation and experimental study of the Vickers indentation testing of the Al2O3 ceramic coated by diamond-like carbon (DLC) layer were conducted. The numerical analysis was implemented by a two-dimensional finite element (FE) axis symmetry model. FE analysis results gave insight into the fracture mechanism of DLC films coated on brittle ceramic (Al2O3) substrates. The maximum principal stress field was used to locate the most expected area for crack formation and propagation during the Vickers indentation testing. The results show that the median crack initiates in the interface under indenter, before ring crack occurs as the indenter presses down. Finally, the plastic deformation appears when the indenter penetrates into the substrate. The thicker DLC coating increases the Vickers hardness and fracture toughness.

OBJECTIVE A recent revision of the FIGO staging system does not recommend the mandatory use of cystoscopy and sigmoidoscopy. The objective of this study was to assess the clinical utility of CT or MRI scans for ruling out bladder or rectal invasion and determine the indication for endoscopy in patients with cervical cancer. METHODS We retrospectively reviewed 769 patients with cervical cancer, who underwent imaging and endoscopic work-up between January 1997 and December 2010. Using endoscopy as the standard reference for comparison, we calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the imaging modality for bladder or rectal invasion. RESULTS The CT scan showed 68.2% and 85.7% for sensitivity and 96.4% and 98.9% for specificity in detecting bladder and rectal invasion, respectively. CT scan provided a low PPV (51.7%, 54.5%) and a high NPV (98.2%, 99.8%). MRI scan showed 88.0% and 75.0% for sensitivity and 93.1% and 98.9% for specificity in detecting bladder and rectal invasion, respectively. MRI scan provided a low PPV (35.6%, 42.9%) and a high NPV (99.4%, 99.7%). The accuracies of CT and MRI scans in identifying bladder invasion were 94.9% and 92.8%, respectively. The accuracies of CT and MRI in identifying rectal invasion were 98.7% and 98.6%, respectively. CONCLUSION The results of this study demonstrate that additional invasive endoscopy is not necessary for patients who present with no invasion on imaging work-up, and therefore, endoscopy should be considered a tool for confirming cases that are positive for invasion based on imaging work-up.

Silicon carbide film was coated by RF sputtering system onto graphite plate substrate. Surface roughness of substrate was polished by wet polishing with sand paper, number of 3000. RF power was 200 W in 0.4 Pa of argon gas. Deposition holding time was 3hours in 600 °C temperature. Specimens were heat treated by 1200, 1400 and 1500 °C for 1 hour to research the effect of heat treatment on SiC coating layer. Atomic Force Microscope (AFM) was used to characterize the surface morphology and the Sq surface roughness. AFM was used to investigate the grain size and roughness of the surface of thin coating film. X-ray diffraction (XRD) was used for detecting the coated SiC thin film by thin film mode. FE-SEM was used to characterize the microstructure of SiC coating film.

In this study, we have developed the method for obtaining a conductive DLC layer on glass substrate of 30×30mm size by adding Nitrogen or Silane gas during CVD(Chemical Vapor Deposition) growth. The growth rate and electrical conductivity were investigated under different plasma deposition condition. In addition, we measured the optical transmittance spectra of the films. From the measurements of optical transmittance in range of 300 to 1150 nm wavelength, an optical transmittance is obtained from 80% to 90% from the DLC films grown with lower gas flow rates. The characteristic of DLC films were evaluated by various techniques including alpha step surface profiler, micro Raman spectroscope, X-ray diffraction(XRD) and Nano- indentation.

High density plasma etching of SnO 2 and ZnO films was performed in chlorine- ( Cl 2/ Ar and BCl 3/ Ar ) and fluorine-based ( CF 4/ Ar and SF 6/ Ar ) inductively coupled plasmas. The etch process window for fabricating metal oxide nanowires with high aspect ratios including high and controllable etch rates, high etch selectivities to mask material and high anisotropy was established. Maximum etch rates of ~2050 Å/minute ( BCl 3/ Ar ) and ~1950 Å/minute ( SF 6/ Ar ) for ZnO , and ~1950 Å/minute ( Cl 2/ Ar ) and ~2000 Å/minute ( SF 6/ Ar ) for SnO 2 were obtained. Ni was found to provide very high etch selectivities with maximum values of ~67 to SnO 2 and ~17 to ZnO , respectively.

Recently, advances in mobile communication and location identifying technology of the moving object is evolving. Therefore, the location-based services based on request for service have increased and a variety of the indexing for the position management of moving objects has been studied. Because the index based on Euclidean space are no restriction of movement, it is difficult to apply to the real world. Also, there is additional cost to find adjacent road segments in road networks-based indexing. Existing studies of fixed static objects such as buildings or hospitals are not considered. In this paper, we propose an efficient road networks-based indexing for management of current positions. The proposed indexing partitions road networks by grids and has integrated road connection informations and manage separated extra indexing for fixed static objects. Through the experiment, we show that the proposed indexing based on road networks improves the performance of operation for search or update than existing indexing.

R&D activities currently being undertaken for Korean Helium Cooled Solid Breeder (HCSB) Test Blanket Module (TBM) include joining technologies of structural materials, breeder pebble material development, and measurement of pebble bed characteristics. The joining performance of ferritic–martensitic steel is evaluated. TIG welding for ferritic–martensitic steel is evaluated to find welding conditions with two different current modes. The fabrication methods of lithium silicate powder and lithium titanate pebble are under development using special process. The Li2TiO3 pebbles showing an average diameter of 1.8 mm was fabricated by water-based sol–gel method. The Li4SiO4 powder with the particle size of about 200 nm was synthesized by PVA polymer solution method. The method of silicon carbide coating on the graphite pebble is investigated, and its possibility is verified based on the coating results on the graphite plate. Sputtered SiC coating layer was crystallized by high temperature heat treatment. The measurement method and database of the thermal properties of the pebble and pebble bed are important for the design of TBM as well as breeding blanket. The initial characteristics of the pebbles are assessed measuring the effective thermal diffusivity of graphite pebble by laser flash method.

Rudders of large container ships are easily affected by cavitation, which is well known to be induced by significant axial flows behind a propeller and discontinuities in the rudder. Among several methods to prevent or reduce the cavitation erosion occurred in the rudder, painting is gaining a lot of attention because it can be employed easily and cheaply. To conduct erosion tests properly, the simulation of heavily erosive cavitation is necessary. This can be generated using an inclined propeller dynamometer in the medium-size cavitation tunnel of MOERI (Maritime & Ocean Engineering Research Institute). The inclined shaft of the propeller creates strong cavitation, which occurs around the root of the propeller blade. This cavitation creates impacts through the collapsing process that are very severe, and are useful for realistic and efficient cavitation erosion tests. In the present study, the newly developed cavitation erosion test method is successfully employed to evaluate marine coatings that is mainly composed of epoxy elastomer or silicone polymer material. Silicone polymer-type paint B was found to have three times larger endurance than epoxy elastomer-type paint A.

Boron doped diamond films were synthesized on silicon substrates by microwave plasma chemical vapor deposition (MPCVD) technique. The effect of B 2 O 3 concentration varied from 1000 to 5000 ppm on the field emission characteristics was examined. The surface morphology and quality of films were characterized by scanning electron microscope (SEM) and Raman spectroscopy. The surface morphology obtained by SEM showed variation from facetted microcrystal covered with nanometric grains to cauliflower of nanocrystalline diamond (NCD) particles with increasing B 2 O 3 concentration. The Raman spectra confirm the formation of NCD films. The field emission properties of NCD films were observed to improve upon increasing boron concentration. The values of the onset field and threshold field are observed to be as low as 0.36 and 0.08 V/μm, respectively. The field emission current stability investigated at the preset value of ∼1 μA is observed to be good, in each case. The enhanced field emission properties are attributed to the better electrical conductivity coupled with the nanometric features of the diamond films.

In this study, diamond thin films were deposited on tungsten carbide tools using surface-wave plasma-enhanced chemical vapor deposition (SWP-CVD). To eliminate the adverse effects of cobalt on the diamond deposition process, the cobalt was removed from the surface of the tools by etching with Murakami’s reagent for various times (30, 60, and 120 min). The cutting performance of the untreated and the diamond-coated WC tools was examined by performing cutting test on carbon fiber-reinforced plastic (CFRP). The results showed that all the diamond-coated tools exhibited great improvement on the durability and wear resistance compared to the uncoated one. In addition, the diamond-coated tool lift time is found to be proportional to the etching time. An increase more than twofold has been achieved when the etch time was increased from 30 min to 120 min.

Fretting occurs at the contact area between two materials under load and in the presence of minute relative surface motion by vibration or external force. Bearings, clutches, riveted and bolted lap joints are subjected to fretting damage. Friction coefficient, materials of the specimen, contact surface pressure, relative slip amplitudes, temperatures and environment have an effect on the fretting. In this study, fretting wear test is conducted with SCM415 (Cr–Mo alloy steel) which are much used for making gears and shafts because of its excellent machinability, good mechanical properties and low cost, compared with those of the existing machine structural steels. In order to determine the fretting wear type, fretting wear fixture which can be attached to the servo hydraulic fatigue testing machine is made. And then, specimens and fretting pad with a constant curvature are made of SCM415 materials. Different normal forces and displacement amplitudes are applied to the fretting pad and diamond-like carbon (DLC) is coated on the fretting pad for fretting wear test.

Aluminum alloy 6061 is widely used for space development since the advent of space era irradiated with protons using cyclotron. In the condition of confined 5-mm thick wall, protons of 5 MeV, the case of low energy showed larger damage in the structure of aluminum alloy than those of 25.4 MeV, the case of high energy. Protons of 5 MeV stopped and transferred all kinetic energy into the 5-mm thick wall, on the other hand, protons of 25.4 MeV were penetrating and a few energy transferred. Elastic modulus reduced, but elongation was increased, finally tensile strength obviously showed that longer duration of exposure yielded weaker strength of material.

Silicon carbide ( SiC ) materials have been extensively studied for high temperature components in advanced energy system and advanced gas turbine. The SiC ceramics have been fabricated by a NITE (Nano Infiltration Transient Eutectic Phase) Process, using Nano- SiC powder. The sintering additives used for forming liquid phase under sintering process, used the sintering additives ratios were an Al 2 O 3- Y 2 O 3 system or add SiO 2 contents. A major R&D focus for the SiC ceramics is the production to obtain high purity SiC ceramics. In this study, we investigated roles of the sintering additives( Al 2 O 3: Y 2 O 3) to fabrication of the SiC ceramics. The effects of SiO 2 contents and density properties of the SiC ceramics were also investigated. To investigate the effects of SiO 2, Al 2 O 3/ Y 2 O 3 composition were fixed and then SiO 2 ratios were changed as several kinds, and to confirm the effects of sintering additives ratios ( Al 2 O 3: Y 2 O 3) they were changed between 4:6 and 6:4 in x wt.%.

Silicon incorporated diamond-like carbon films up to 6.2 at. % (DLC- Si ) were deposited onto a high speed steel samples by using a radio frequency plasma-enhanced chemical vapor deposition method. The influence of silicon doping on chemical composition, bonding structure, hardness, and adhesion of DLC films was investigated. Hexamethyldisilane ( HMDS ) gas was used as a silicon source with Ar carrier gas ranging from 0 to 15 sccm. Also, the mixtures of methane ( CH 4) and Ar gases were used as precursor gases. The addition of silicon into the DLC film was found to lead an increase of bonding ratio ( sp 3/ sp 2), hardness and critical adhesion

In this study, fatigue characteristics of C70S6 and SMA40 materials as a potential application in connecting rod for an Internal Combustion (IC) engine were investigated. An average fatigue life of 140,200 and 168,700 cycles and a fatigue limit of 432 and 437 MPa were determined for C70S6 and SMA40 specimens, respectively. However, when tested under the fretting condition, the fatigue lifetime was decreased by 77.8% and 20% and the fatigue limit was reduced to 96 and 350 MPa for C70S6 and SMA40 specimens, respectively. From the observations of fracture surfaces, it was confirmed that the fretting played a critical role in introducing many cracks at the initial stage of fatigue. It is clearly shown in this study that special attention should be given to the fatigue behavior of given materials under fretting condition to ensure reliable design and application of components in an automobile.

The very erosive cavitation is simulated by an inclined propeller dynamometer in the medium-size cavitation tunnel of MOERI. The inclined shaft for propeller makes strong cavitaion, which occurs around the root of a propeller blade. The cavitation begins at the leading edge of the propeller and contracted toward the trailin g edge through the re-entrant jet action. The cavity focused on the region near the trailing edge collapsed over the blade surface. As the impact pressure by the cavitation collapsing is too strong, it can damage the blade surface in the form of pit. This cavitation impacts created by the collapsing process are similar to the full-scale ones and are different from those by other erosion test methods. The newly developed cavitation erosion test method can be applied to evaluate the materials such as metals, ceramics and coatings in terms of cavitation resistance. ※Keywords: Erosion test(침식 시험), Cavitation collapsing(캐비테이션 붕괴), Inclined propeller dynamometer(경사류 프로펠러 동력계), Coating(도료), Pit(파공) 접수일: 2009년 9월 18일, 승인일: 2010년 2월 8일 교신저자: ppaik@moeri.re.kr, 010-3574-4341

A new dual-band Wilkinson divider structure is proposed for the arbitrary power division ratio and matched output ports.The compact dual-band stubbed Π sections are employed in both the Wilkinson divider and the output matching section. It has simple structure based on the compact open stub topology and the overall divider length can be reduced in half as compared with similar works based on the two cascaded section transformers. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1187–1190, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25119

Cavernous hemangioma of the breast is a rare benign vascular tumor. It is usually diagnosed as non-palpable mass during imaging examination, incidentally. Common sonographic finding of the breast hemangioma is a superficially located, oval shape, circumscribed margin mass. But the appearance of breast hemangioma is variable and it can be difficult to diagnose in preoperatively. Here, we report a 68-year-old female case with palpable breast mass and increased size on follow up ultrasonography.

A 52-year-old male complained of a painless, firm, and slow-growing mass in his right breast outer portion. The chest CT revealed a 3.3 cm-sized oval shaped, microlobulated, mild enhancing mass. Ultrasound showed a microlobulated marginated heterogeneous hypoechoic mass with internal vascularity and calcifications in the mass. On the ultrasound-guided core needle biopsy, the mass was confirmed as a benign granular cell tumor (GCT). The patient transferred to another hospital and underwent surgical removal of the lesion. GCT of the breast is uncommon and mostly benign neoplasm to originate from Schwann cell. Clinical and radiologic features of GCTs, including CT and ultrasound images, mimic malignancy and make diagnosis of GCT more difficult. The CT images of GCTs are much rarely reported. Physicians and radiologists must be aware of radiologic characteristics of this rare benign tumor for male breast, to avoid misdiagnosis this tumor for breast malignancy and overtreat.