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The burden on ship owners and shipping companies has increased due to the International Maritime Organization’s (IMO's) environmental regulations. The countermeasures against these regulations involve using low sulfur oil, installing scrubbers, and using liquefied natural gas (LNG) fuel. Among them, the demand for LNG propulsion ships is currently the highest. The most widely used storage device for LNG fuel is the IMO type C tank. The structure of the IMO type C tank is divided into a container part (pressure vessel) and a support part (saddles). In general, epoxy resin for load-bearing and wooden blocks are applied between the pressure vessel and saddles. When the saddles of the saddle-tank integrated fuel tank are welded to a hull, melting of the resin or burn-damage on the wooden blocks may occur due to the welding heat. Therefore, in this study, the temperature distribution of the saddle is checked, and the appropriate minimum height of the saddle is proposed to prevent the functional loss of the resin and wooden blocks during the installation of the saddle-tank integrated fuel tank. In addition, the initial deformation of the saddle according to the welding direction and sequence is evaluated to identify the effect of the welding on the installation of the saddle-tank separated fuel tank.

We demonstrated the sensing properties and adsorption mechanism of NO2 molecules of monolayer graphene and multilayer graphene encapsulated ZnO QDs for NO2 gas adsorption. The gas response value of ZnO-multilayer graphene (ZMLG) QDs was approximately 23 % and 7.2 and 25.5 times higher than that with ZnO-monolayer graphene (ZG) and ZnO QDs, respectively. The surface potential change of ZMLG QDs increased up to 14.25 times compared to ZnO QDs and 6.33 times increased compared to ZG QDs. We proposed an accurate adsorption mechanism for the improvement of the detection behavior that is occured by covering the graphene shells into ZnO QDs by the Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS), and SKPM measurement. These results are expected to increase the accuracy of gas sensor characteristic analysis.

Single-molecule localization microscopies have gained much attention for their efficient realization of a sub-diffraction-limit imaging with the resolution down to the 10-nm range. In contrast to conventional localization microscopes, which rely on particular fluorescent probes in specific conditions, metamaterial-assisted super-resolution microscopies can be implemented with any fluorescent dye under general conditions. Here, we present a systematic study of fluorescence engineering in metamaterial assisted localization microscopy by using cyclic group metasurfaces coated with a fluorescent film. Tailored variations are clearly demonstrated in both the photoluminescence intensity and the photobleaching lifetime of fluorophores based on the spatially varied Purcell effect near the metasurfaces. The enhanced emissions and blinking dynamics of the fluorophores on these metasurfaces lead to an increased signal-to-noise ratio, and therefore give rise to a super-resolution localization image with 0.9-nm localization accuracy. Our results are not only beneficial for super-resolution localization imaging but also push the control of light–matter interactions beyond the diffraction limit.

A malignant rhabdoid tumor is an aggressive tumor that occurs mainly in the kidney of infants and children. When it occurs in extrarenal sites, it is referred to as an extrarenal malignant rhabdoid tumor. Although a few cases of malignant rhabdoid tumor occuring in the central nervous system, liver, brain, skin, and soft tissue have been reported, it is rarely observed in the stomach. We report the imaging findings of a malignant rhabdoid tumor of the stomach that mimicked a gastric lymphoma in a patient who presented with melena.

Backgrounds/aims With the improvement of hygiene, the incidence of amebic liver abscess is decreasing in South Korea. On the other hand, there is little data on the status of amebic liver abscess compared to pyogenic liver abscess. Methods Patients with an amebic liver abscess, in whom Entamoeba histolytica (E. histolytica) IgG was positive, were identified retrospectively in a university hospital. The clinical, laboratory, and radiological characteristics of amebic liver abscess were compared with those of pyogenic liver abscess in the same period. Results Between March 2010 and October 2016, 413 patients with a liver abscess were identified. Among them, the serologic test for E. histolytica was performed in 209 patients. Fifteen (7.2%) were classified as an amebic liver abscess, and the remainder were diagnosed with a pyogenic liver abscess. The age, gender, white blood cell, and CRP was comparable between the two groups. Procalcitonin was lower in amebic liver abscess than the pyogenic one. On CT, peripheral rim enhancement was more frequent, but cluster signs were not observed in amebic liver abscess compared to pyogenic liver abscess. None of the patients with amebic liver abscess died. In contrast, the mortality of pyogenic liver abscess was 4.7%. Conclusions Amebic liver abscess should still be considered as one of the causes of liver abscess in Korea. It is difficult to discriminate an amebic liver abscess from a pyogenic liver abscess only according to the clinical, laboratory, and radiologic findings. Therefore, it is necessary to perform a serologic test for E. histolytica for a precise evaluation of liver abscess in a high-risk group.

For the management of rotating machines, machine learning (ML) has been researched with the use of feature parameters that have physical and statistical meanings of vibration signals. Genetic algorithm (GA) and principal component analysis (PCA) are the algorithms used for the selection or extraction process of the features; equipment condition. This study proposes a new method to maximize the advantages of the extraction and selection algorithms, thereby improving the fault classification performance. The proposed method is estimated in a variety of equipment conditions by selecting and extracting the effective features for status classification. To evaluate the performance of the fault classification through feature selection and extraction of the ML, a comparative analysis with the proposed method and the original method is also performed. With Lab-scale gearbox, several types of fault tests are conducted, and seven different fault types of equipment conditions, including the normal status, are simulated. The results of the experiments show that, the performance of classification of GA for feature selection is 85%, while PCA for feature extraction is 53%. The performance result of the proposed method for fault classification is 95%, meaning that the performance of fault diagnosis is more efficient in terms of discriminative learning than the original method. Therefore, the proposed method with feature extraction and selection algorithm can improve the fault classification performance by 10% and more for fault diagnosis through ML.

A structure of flexible glass/flexible transparent conducting electrode (TCE) comparable with the conventional glass/indium tin oxide (ITO) substrate is proposed by combining an Ag NW + PEDOT:PSS hybrid TCE (h‐TCE) with triple‐layer a‐SiNx:H/n‐SiOxNy/h‐SiOx ultrahigh barrier (UHB) films. The UHB films have dual functions of both moisture barriers with a water vapor transmission rate (WVTR) of 1.6 × 10−5 × g m−2 day−1 and antireflection (AR) with a gradient refractive index. Flexible PTB7:PC70BM‐based organic photovoltaics (OPVs) with the AR‐UHB film achieve a maximum power conversion efficiency (PCE) of ηmax = 8.33%, saturation current density (Jsc) of 17.67 mA cm−2, and external quantum efficiency (EQE) of 63.3%, which are higher than ηmax = 7.63%, Jsc = 15.25 mA cm−2, and EQE = 59.26% of the OPVs on glass/ITO. These result from the increase in the absorption of the donor PTB7 due to the AR effect of the UHB films. A long‐term stability of the AR‐UHB encapsulation layer in damp heat (40 °C/85% relative humidity [RH]) is confirmed by the result that the measured T80 and T50 values for the OPV device on glass/ITO encapsulated with the AR‐UHB film are about 1008 h (42 days) and 2205 h (92 days), respectively.

In this study, a useful solution is proposed for assessing the safety of the ship’s hull damaged by grounding in Northern Sea Route (NSR) or Arctic sea. In particular, the residual ultimate longitu...

Heterotopic pancreas is often an incidental finding and can be found at the stomach. However, heterotopic pancreas containing abundant fat is very rare. Fatty replacement of the pancreas is the most frequent pathologic finding, but the precise etiology of the entity remains unclear. The pathological findings observed in the pancreas can also occur in the heterotopic pancreas. Here, we present a case of heterotopic pancreas in the stomach. On CT and MR imaging, it manifested as a predominant fat-density submucosal mass with enhancing solid component.

The stability of intermetallic second-phase particles (SPPs) in coated Zircaloy-2 was studied in 700 °C steam environments up to 20 hours. Hydrogen generated from high-temperature steam oxidation of uncoated Zr-induced δ-hydrides formation in the Zircaloy matrix. Synchrotron XRD demonstrated that longer exposure times increased hydride peak intensity and decreased intermetallic SPPs’ peak intensity. Cross-sectional SEM analysis verified the intermetallic SPPs’ volume fraction reduction. The size distribution of intermetallic SPPs was characterized and larger particles were dissolved at longer oxidation time. A correlation between the hydrogen concentration and the volume fraction of intermetallic SPPs at 700 °C steam environment was found, with the volume fraction of SPPs decreasing as hydrogen concentration increases.

In our study, to optimize the electron–hole balance through controlling the electron transport layer (ETL) in the QD-LEDs, four materials (ZnO, ZnGaO, ZnMgO, and ZnGaMgO NPs) were synthesized and applied to the QD-LEDs as ETLs. By doping ZnO NPs with Ga, the electrons easily inject due to the increased Fermi level of ZnO NPs, and as Mg is further doped, the valence band maximum (VBM) of ZnO NPs deepens and blocks the holes more efficiently. Also, at the interface of QD/ETLs, Mg reduces non-radiative recombination by reducing oxygen vacancy defects on the surface of ZnO NPs. As a result, the maximum luminance (Lmax) and maximum luminance efficiency (LEmax) of QD-LEDs based on ZnGaMgO NPs reached 43 440 cd m−2 and 15.4 cd A−1. These results increased by 34%, 10% and 27% for the Lmax and 450%, 88%, and 208% for the LEmax when compared with ZnO, ZnGaO, and ZnMgO NPs as ETLs.

FeAl(Cr) thin-film depositions on Zircaloy-2 were studied using transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) with respect to oxidation behavior under simulated boiling water reactor (BWR) conditions and high-temperature steam. Columnar grains of FeAl with Cr in solid solution were formed on Zircaloy-2 coupons using magnetron sputtering. NiFe2O4 precipitates on the surface of the FeAl(Cr) coatings were observed after the sample was exposed to the simulated BWR environment. High-temperature steam exposure resulted in grain growth and consumption of the FeAl(Cr) layer, but no delamination at the interface. Outward Al diffusion from the FeAl(Cr) layer occurred during high-temperature steam exposure (700 °C for 3.6 h) to form a 100-nm-thick alumina oxide layer, which was effective in mitigating oxidation of the Zircaloy-2 coupons. Zr intermetallic precipitates formed near the FeAl(Cr) layer due to the inward diffusion of Fe and Al. The counterflow of vacancies in response to the Al and Fe diffusion led to porosity within the FeAl(Cr) layer.

In the development of a fault diagnosis and condition monitoring in the gearbox, the research is a quantitative analysis and a test of gear damage effect on the vibration of the gearbox. The lab-scale gearbox test device that builds the several types of fault such as gear tooth breakage, Misalignment and looseness occurred by gearbox fault simulator. This paper presents feature analysis through the GA (genetic algorithm) and SVM (support vector machine) of machine learning, the performance of feature classification is evaluated by faults on the gearbox. the research compared the possibility of classification through the feature of the existing rotor failure classification and the new feature applicable to the gearbox. In addition, the trend of selected features of combined fault indicates clustering at the same point on three dimensions. Therefore, the results of feature-based analysis considering gearbox faults are about 98 %, which verifies the performance for gearbox fault diagnosis.

In the development of a fault diagnosis and condition monitoring in the gearbox, the research is a quantitative analysis and a test of the effect of gear damage on the vibration of the gearbox. The lab-scale gearbox test device that builds the several types of fault such as gear tooth breakage, misalignment and looseness occurred by gearbox fault simulator. This paper presents feature analysis through the PCA (principal component analysis), GA (genetic algorithm) and SVM (support vector machine) of machine learning, the performance of feature classification is evaluated by faults on the gearbox. In addition, the trend of selected features of combined fault indicates clustering at the same point on three dimensions. Therefore, the results of feature-based analysis considering gearbox faults are about 99 %, which verifies the performance for gearbox fault diagnosis.

A pulmonary artery aneurysm is an uncommon anomaly. The clinical manifestations are mostly nonspecific, and management is controversial. We report a case of a 67-year-old woman with a main pulmonary artery aneurysm who did not take surgical intervention. Subsequently, there was no increase in size for 3 years.

Cardiac hemangiomas are very rare benign neoplasms that are usually asymptomatic. Although there are often found incidentally during echocardiography, other imaging modalities such as computed tomography, magnetic resonance imaging, and coronary angiography are needed to establish a diagnosis. Surgical excision is therefore recommended to confirm the diagnosis and avoid potential complications. We report a case of asymptomatic cardiac hemangioma that was discovered incidentally during echocardiography.

This paper designs and analyzes radar antenna for automobiles that can operate at 24 GHz and 77 GHz. This radar antenna is designed on LTCC substrate for highly integrated module. The LTCC substrate has a reflector at an arbitrary position to improve the antenna patterns. The pattern of the reflector antenna has dual beam characteristics that the central portion of the pattern is reduced. Therefore, this paper adds an air layer to the LTCC substrate to improve this disadvantage. As a result, the pattern has been improved to have a single beam characteristic. This paper designs and analyzes a single beam offset parabolic reflector(OPR) antenna for a highly integrated module that can operate in the millimeter wave. This paper also suggests the possibility of integration of monopole antennas for short and long distance radar systems.

Coaxial type piezoelectric energy generator (C-PEG) nanofiber was fabricated by a self-designed continuous electrospinning deposition system. Piezoelectric PVDF-TrFE nanofiber as an electroactive material was electrospun at a discharge voltage of 9–12 kV onto a simultaneously rotating and transverse moving Cu metal wire at an angular velocity of ω g = 60–120 RPM. The piezoelectric coefficient d33 of the PVDF-TrFE nanofiber was approximately −20 pm V−1. The generated output voltage (V G) increased according to the relationship exp(-α P) (α = 0.41– 0.57) as the pressure (P) increased from 30 to 500 kpa. The V G values for ten and twenty pieces of C-PEG were V G = 3.9 V and 9.5 V at P = 100 kpa, respectively, relatively high output voltages compared to previously reported values. The high V G for the C-PEG stems from the fact that it can generate a fairly high V G due to the increased number of voltage collection points compared to a conventional two-dimensional (2-dim) capacitor type of piezoelectric film or fiber device. C-PEG yarn was also fabricated via the dip-coating of a PDMS polymer solution, followed by winding with Ag-coated nylon fiber as an outer electrode. The current and power density of ten pieces of C-PEG yarn were correspondingly 22 nA cm−2 and 8.6 μW cm−3 at V G = 1.97 V, higher than previously reported values of 5.54 and 6 μW cm−3. The C-PEG yarn, which can generate high voltage compared to the conventional film/nanofiber mat type, is expected to be very useful as a wearable energy generator system.

Purpose The aim of this study was to evaluate added value and diagnostic threshold value of thyroglobulin measurement in the fine-needle aspiration washout for detecting cervical lymph node metastasis from papillary thyroid cancer on pre and postoperative patients. Materials and Methods Total 219 cervical lymph nodes from 180 patients with papillary thyroid cancer were evaluated for fine needle aspiration cytology and thyroglobulin in fine needle aspiration (FNA-Tg), using immunometric chemiluminescent assay. Eighty-six patients were preoperative and remaining 94 patients were on follow up after total thyroidectomy. Final diagnoses were made on pathology of dissected lymph nodes or follow-up examination for at least 12 months. Results One hundred and twelve metastatic lymph nodes were finally confirmed in 94 patients out of total 180 patients. Sensitivity of FNA-Tg was 99.1, 98.21, 97.20%, respectively with threshold level at 1, 10, serum Tgng/mL, which were higher sensitivity of fine needle aspiration. Combined FNA and FNA-Tg with threshold at 1, 10, 100 ng/mL raised sensitivity and specificity to 100%, respectively. All 6 lymph nodes that were false negative on FNA were correctly diagnosed as metastasis on FNA-Tg with threshold of 1, 10, 100, and serum thyroglobulin. FNA-Tg with threshold level at 100 ng/mL combined FNA showed highest sensitivity (100%) and specificity (97.56%) on preoperative patient groups among the 1, 10, 100, serum Tg threshold value. But, FNA only showed adequately high sensitivity (100%) and specificity (96.96%) on postoperative patient groups. Using receiver operating characteristic curve (ROC) curve analysis, cut off value was 57.69 in total patient, 78.66 in preoperative patient, and 32.81 in postoperative patient. Conclusion FNA-Tg combined with FNA showed excellent sensitivity and specificity. FNA-Tg showed very high sensitivity and specificity at threshold level 78.66 ng/mL in preoperative patients, but FNA-Tg had less benefit on the postoperative patient group, having high sensitivity and specificity with FNA alone.

Leiomyosarcoma is a malignant tumor that typically originates from either the uterus or the retroperitoneum. Furthermore, primary adrenal leiomyosarcoma is an extremely rare condition. Owing to its radiological non-specificity, differentiating leiomyosarcoma from other tumor types in the adrenal gland is difficult. We report the imaging findings of a primary adrenal leiomyosarcoma in a patient who presented with left upper quadrant abdominal pain, which increased by more than 1 cm in diameter in two years. Primary adrenal leiomyosarcoma was diagnosed considering the subsequent surgical and histopathologic findings.

Recently, radar technology to support safe driving is one of the sectors receiving a lot of attention for auto-navigation system of a vehicle. In particular, adaptive cruise control (ACC) radar in the W-band is important. The horn antenna has advantages to achieve high gain and low VSWR in the millimeter-wave band because it is commonly simple structure. In this paper, the monopole Yagi-Uda-fed waveguide pyramidal horn antennas are designed with an optimum size 20x20x30mm3 to operate at the W-band. As a result, this paper presented the possibility of the design of a millimeter-wave pyramidal horn antenna for automotive radar systems.

Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Republic of KoreaReceived 30 November 2013, revised 14 May 2014, accepted 21 May 2014Published online 30 June 2014Keywords electrical properties, optical absorption, organic solar cells, silver, transparent electrodes, zinc tin oxide

We report on a novel, simple and easy method to produce graphene layers using chemically synthesized ZnO–graphene quasi core–shell quantum dots. Initially, graphite powder was partially oxidized by acid treatment of graphite powder, which was then mixed with zinc acetate dihydrate in a dimethyl formamide solution. During this process, graphene sheets were detached from the graphite oxide layers through a layer-by-layer chemical peel-off and then partially covered from ZnO quantum dots which formed in the dimethyl formamide solution. Therefore, the ZnO–graphene quantum dots were dissolved in hydrochloric acid solution and then pure graphene layers were extracted from solution. The structural, optical, and electrical properties of obtained graphene layers were analyzed by using X-ray diffraction, transmission electron microscope, Raman spectroscopy, X-ray photoemission spectroscopy instrument.

The objective of this paper is to develop a modified Paik–Mansour formula for the ultimate strength calculations of ship hulls subject to vertical bending moments. The method is based on a credible bending stress distribution over the hull cross-section presumed at the ultimate limit state. The accuracy of this method is demonstrated through comparison with computations obtained using more refined methods, such as non-linear finite-element method, intelligent super-size finite-element method, and idealised structural unit method. Statistical analysis of the hull girder ultimate strength based on comparisons among the various computations is carried out in terms of their mean values and coefficients of variation. The original Paik–Mansour method is found to be inapplicable to the case of a pure vertical bending moment depending on the ship's hull type and/or vertical bending direction, but the modified Paik–Mansour method is more general and is able to resolve this issue.

This paper presents the results of an investigation of the effect of lateral pressure on the progressive hull collapse behaviour of a double-hull oil tanker subject to vertical bending moments in both the sagging and hogging conditions. As an illustrative example, a Suezmax-class double-hull oil tanker designed by the Common Structural Rules (CSR) method is considered. The ANSYS nonlinear finite element method (NLFEM) is employed for the progressive hull collapse analysis. The effects of lateral pressure – static (anchored condition) and dynamic (operating condition) – are investigated in both the full-load and ballast conditions. To check the accuracy of ultimate hull girder strength analysis methods, Dow's test hull is also applied together with Suezmax class oil tanker under conditions of vertical bending moment but without lateral pressure loads. In this regards, the NLFEM method is compared with ALPS/HULL intelligent supersize finite element method (ISFEM) programs and International Association of Classification Societies (IACS) CSR method, which applies the idealized structural unit method (ISUM) (also called the Smith method). The important insights developed from the present study are documented.

We fabricated an a-IGZO thin film transistor (TFT) with AZO/Ag/AZO transparent multilayer source/drain contacts by rf magnetron sputtering. a-IGZO TFT with AZO/Ag/AZO multilayer S/D electrodes (W/L = 400/50 µm) showed a subs-threshold swing of 3.78 V/dec, a minimum off-current of 10-12 A, a threshold voltage of 0.41 V, a field effect mobility of 10.86 cm2/Vs, and an on/off ratio of 9ƒ 109. From the ultraviolet photoemission spectroscopy, it was revealed that the enhanced electrical performance resulted from the lowering of the Schottky barrier between a-IGZO and Ag due to the insertion of an AZO layer and thus the AZO/Ag/AZO multilayer would be very appropriate for a promising S/D contact material for the fabrication of high performance TFTs.