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In the present work, we have fabricated organic photovoltaic cells consisting of ITO/PEDOT:PSS/P3HT:PCBM/DMDCNQI/Al using a dip-coating method with various solvent systems. We have investigated solvent effects (such as solubility, viscosity and vapor pressure) in deposition of a thin DMDCNQI buffer layer on the performance of organic photovoltaic cells. The solvent system which had low viscosity and good solubility properties, made a dense and uniform DMDCNQI ultra thin film, resulting in a high performance device. In particular, a prepared organic photovoltaic cell was fabricated using a cosolvent system (methanol:methylenechloride = 3:1) and showed a maximum power conversion efficiency of 4.53%.

Contact resistance between a metal electrode and an organic active layer is one of the most critical issues in the research and development of organic electronic devices. In the present work, we have fabricated vertical type organic light emitting transistor (OLET) using P3HT as a organic active semiconductor and DMDCNQI as a charge transfer material. The device configuration is ITO/PEDOT:PSS/P3HT/Al gate/P3HT/DMDCNQI/Al. The characteristics of OLET were investigated from the measurement of current-radiance voltage characteristics The needle form of highly conducting DMDCNQI-Al charge transfer complex was obtained, which resulted in the improvement of device performance due to the low organic-metal contact resistance and the high electron transport ability.

In the previous work, we have reported that organic photovoltaic (OPV) cells using DMDCNQI as an n-type second dopant material showed a high power conversion efficiency (PCE). In the present work, we have synthesized a novel DHDCNQI with long alkyl chains to improve the compatibility between the DHDCNQI dopant molecule and host P3HT polymer. We have fabricated OPV cells consisting of ITO/PEDOT:PSS/P3HT:PCBM:DHDCNQI/Al. We have investigated the characteristics of theses OPV cells using DCNQI derivative dopants from the measurements of the incident photon-to-current collection efficiency and photocurrent. The OPV cell using 3 wt% DHDCNQI exhibited a high PCE of 3.29% due to the high charge separation efficiency, good compatibility and low trap site effect.

Controlling for day-to-day variation is a key issue in estimating long-term dietary exposure to heavy metals using 24-hour recall (24HR) data from a relatively small number of days.This study was conducted to estimate long-term dietary exposure to lead, cadmium and mercury among Korean children using the Iowa State University (ISU) method and to assess the contributions of different food groups to heavy metal intake.We analyzed 2 days of 24HR data from 457 children between 0 and 6 years of age in 2010. Using bootstrapped concentration data for 118 representative foods, 93.5% of total intake was included in the exposure estimates in this study. Using the 2-day exposure data, we estimated long-term exposure by controlling for within-individual variation using the ISU method.The long-term dietary exposure estimates (mean±standard deviation) for lead, cadmium, and mercury were 0.47±0.14, 0.38±0.20, and 0.22±0.08 μg/kg bw/day, respectively. For lead and cadmium, the percentages of children whose exposure was greater than the reference value were 35 and 42%, respectively. Fruits were an important source of lead exposure, and cereal and fish and shellfish made the greatest contributions to the total cadmium and mercury exposure.Our findings also suggest that the long-term exposure to lead and cadmium was somewhat greater than the reference values, whereas mercury exposure was well below than the reference value in this population. Further studies may be necessary to evaluate the food items contributing to heavy metal exposure, and continuous monitoring is needed to ensure the safety of food intake and dietary patterns among vulnerable groups in Korea.

This study introduces 600-km/h wheel-type railway concept propelled by linear synchronous motor (LSM) and deals with the conceptual design for LSM system. The LSM is designed to be of a coreless type, which uses high- Tc superconducting electromagnet (SC-EM) as on-board field magnet. From tentative train parameters, we suggest a conceptual LSM model and its design parameters to achieve the train performances. As high- Tc SC material, we use currently available YBCO tape in designing the SC coil. We produce three SC coil models and estimate tentative design values of each model. The feasibility study described herein provides informative design ranges of LSM for 600-km wheel-type railway.

SUMMARYThree-dimensional (3D) data processing has applications in solving complex tasks such as object recognition, environment modeling, and robotic mapping and localization. Because using raw 3D data without preprocessing is very time-consuming, extraction of geometric features that describe the environment concisely is essential. In this sense, a plane can be a suitable geometric feature due to its simplicity of extraction and the abundance in indoor environments. This paper presents an online incremental plane extraction method using line segments for indoor environments. Our data collection system is based on a “nodding” laser scanner, so we exploit the incremental nature of its data acquisition in which physical rotation and 3D data processing are conducted in parallel. Line segments defined by two end points become supporting elements that comprise a plane, so a large proportion of scan points can be ignored once the line segments are extracted from each scan slice. This elimination of points reduces the algorithm complexity and computation time. Experiments with the tens of complete scan data sets which were acquired from a typical indoor environment demonstrated that our method was at least three times faster than the state-of-the-art methods.

To understand the cut-edge corrosion behaviors of Zn-Al-Mg alloy-coated steel better, mechanistic studies with a Zn-MgZn2 eutectic specimen fabricated by a hot-pressing process were conducted using various electrochemical methods, such as the scanning vibrating electrode technique and galvanic corrosion measurements. The results showed that the MgZn2 phase dissolved preferentially with the galvanic current flowing from the phase to Zn. Mg/Zn cations from the dissolving MgZn2 phase were reduced effectively, facilitating the co-precipitation of Mg(OH)2, Zn5(CO3)2(OH)6, and Zn5(OH)8Cl2·H2O, which was confirmed by X-ray photoelectron spectroscopy. Based on the results, a much longer-lasting corrosion inhibition mechanism of the alloy-coated steel was provided.

The increasing incidence of food allergy (FA) can be attributed to interactions between genes and the environment, but these interactions are not yet fully clear.We aimed to evaluate the interaction between infant genetic variations and maternal dietary patterns to identify risk factors in the development of FA.We used the Cohort for Childhood Origin of Asthma and allergic diseases birth cohort of 1628 infants, born between 2007 and 2015. Maternal dietary intakes were assessed at 26 weeks of pregnancy using a food frequency questionnaire and grouped according to 5 dietary patterns. Infant cord blood samples were genotyped at 12 loci.Among 1628 infants, 147 (9.0%) were diagnosed with FA based on history. A maternal confectionery diet characterized by a higher intake of baked and sugary products during pregnancy was associated with a higher prevalence of FA (adjusted odds ratio [OR] = 1.517, P = .02); this dietary pattern tended to be higher in trans fat (r = 0.498, P.001). Development of FA was associated with longer periods of breastfeeding (adjusted OR = 1.792, P = .03), and this dietary pattern was more significantly related to the development of FA in infants with the homozygous TT genotype of CD14 (rs2569190) and more than 1 copy of GSTM1 and GSTT1.A maternal confectionery diet during pregnancy that majorly consists of baked and sugary products, combined with a longer ensuing period of breastfeeding, may lead to the development of FA, suggesting a harmful effect of trans fats in the infant. Polymorphisms in CD14 and GST in the infant influence FA susceptibility.

Background Attention-deficit hyperactivity disorder (ADHD) is one of the most common psychiatric disorders of childhood and can be associated with obesity. The aim of this study was to reveal the connection between ADHD symptoms, food habits and obesity. Methods We examined 12 350 children (6010 boys, 6340 girls) from 27 elementary schools in Cheonan, the Republic of Korea. The study subjects were 5- to 13-year-old children (9.4 ± 1.7 years). Parents completed the DuPaul ADHD Rating Scale. Food habits were measured by a questionnaire adapted from the Korea Youth Risk Behavior Web-based Survey and a validated mini-dietary assessment tool. The full set of hypothesized associations was tested using covariance structural modelling. Results The prevalence of ADHD was 7.6% and that of obesity was 4.5% in our study population. The data was well fit by the model. ADHD was associated with body mass index (BMI; standardized β = 0.086, P < 0.001). Bulimic dietary behaviours was related to BMI (standardized β = 0.548, P < 0.001). Socio-economic status was associated with BMI (standardized β = −0.017, P = 0.027). Conclusion Our analysis suggested that ADHD was a risk factor for obesity through dietary behavioural change and socio-economic status.

The electron transport layer (ETL) increases the power conversion efficiency (PCE) in organic photovoltaic cells (OPVs) by promoting the formation of ohmic contact between the active layer and the cathode metal. Here, we introduce ytterbium (Yb) as the electron transport layer into inverted OPVs where Yb is evaporated directly onto indium tin oxide (ITO). The inverted OPVs composed of ITO/Yb/P3HT:PCBM/MoO3/Ag recorded PCEs of up to 4.3%, achieving 71% of the fill factor (FF) in one sun irradiation. Over 80% of its original PCE was retained after 30 days. The results indicate that Yb in inverted OPVs is vastly superior to other ETLs as it improves the majority of the parameters including the short circuit current, FF and PCE. In this report, we will discuss the physical and optical functions of Yb in inverted OPVs which make Yb a promising candidate for simultaneously achieving high PCE and good air stability.

We have fabricated a vertical type organic field effect transistor (OFET) using indenofluorenedione derivatives (IF-dione-F) as an n-type organic active material and dimethyldicyanoquinonediimine (DMDCNQI) as an n-type buffer layer. The configuration of the vertical type OFET was ITO (drain)/ IF-dione-F/Metal (gate)/IF-dione-F/DMDCNQI/Metal (source). The characteristics of the vertical type OFET were investigated from the measurements of current-voltage characteristics, contact resistance and device durability. In particular, the device consisting of ITO/TriF-IF-dione/LiAl/ TriF-IF-dione/DMDCNQI/LiAl showed a low turn-on voltage and a high on/off ratio of 6.0 x 10(3).

A series of novel di-α-aminophosphonate derivatives were synthesized by a one-pot method in the presence of PEG-H2 O under ultrasonic irradiation and were characterized by IR, (1) H NMR, (13) C NMR, mass spectrometry, and elemental analysis. The newly synthesized compounds were evaluated for their cytotoxic activities against the human lung cancer cell line H1299 and the human breast cancer cell line MCF7 in vitro by the MTT method. All compounds showed moderate cytotoxic activity on both cell lines, and compounds 4b and 4c showed marked activity.

ObjectiveTo investigate the associations of behavioural problems with dietary patterns and weight status in young children.DesignWe assessed poor social skills and behavioural problems with a seventy-six-item Preschool and Kindergarten Behavior Scale (PKBS) and found three dietary patterns (‘Korean healthy’, ‘animal foods’ and ‘sweets’) in food/food group intake data assessed by an FFQ and analysed using factor analysis. Multiple logistic regression analyses were used to assess the association of diet and weight status with behaviour.SettingPre-schools in the metropolitan areas of Korea.SubjectsA total of 1458 children (mean age 5·2 (sd 0·9) years) from the Practical Approach for Better Maternal and Child Nutrition and Health Study conducted from 2001 to 2005.ResultsThe ‘Korean healthy’ pattern showed a significant inverse association with poor social skills in the second highest quartile group (OR = 0·42; 95 % CI 0·21, 0·82) compared with the lowest quartile group for boys. For girls, the ‘sweets’ pattern was associated with a greater risk of poor social skills (OR = 3·41; 95 % CI 1·29, 9·01 at Q4 v. Q1) and problem behaviours (OR = 2·80; 95 % CI 1·05, 7·43 at Q4 v. Q1). Regarding weight status, both underweight and overweight boys had a higher risk of poor social skills than normal-weight boys.ConclusionsDietary patterns and weight status are important indicators for the behaviour of young children. Healthy and unhealthy dietary patterns, underweight and overweight status, and gender differences should thus be considered for further studies.

Silica or titania uniformly coated multi-walled carbon nanotubes (MWNTs) were fabricated using the tetraethyl orthosilicate (TEOS) or titanium butoxide (TBT) for the application of electrorheological (ER) fluids. The electrorheological and dielectric properties of the two different core/shell nano-tube based ER fluids were measured using rheometer and impedance analyzer. The titania-coated MWNTs ER fluids have shown higher static yield stress as well as dynamic viscoelastic properties compared to the silica-coated MWNTs ER fluids under external electric field. The silica or titania-coated MWNTs ER fluids have shown high permittivity and short relaxation time of interfacial polarization in the dielectric spectra measurement. It was found that the permittivity and electrical conductivity of the MWNTs can be controlled by coating with either the silica or titania onto the functionalized MWNTs.

Tungsten oxide (WO3) was used as an anode buffer layer in conventional poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester (P3HT:PCBM-60) bulk hetero junction (BHJ) cells. Such a buffer layers acts as a hole-extraction layer and reduce series resistance, which leads to better performance of organic electronic devices. Organic photovoltaic (OPV) cells consisting of ITO/WO3/P3HT:PCBM/Al were fabricated. Photovoltaic devices with a short-circuit current density of 7.77 mA/cm2, an open-circuit voltage of 6.1 V, and a power conversion efficiency of 2.61% were achieved. This study revealed that WO3 based cells have significant shunt resistance which contributes to a high fill factor and open-circuit voltage. This demonstrates potential for using WO3 in poly(stylenesulfonate) doped poly(3,4-ethylenedioxythiophene):(PEDOT:PSS)-free systems.

This paper presents a fast Nearest Neighbor Search (NNS) algorithm for geometric data sets, based on a modified k-d tree using the cache technique. First, the tree-based search process of our algorithm starts from an appropriate (cached) leaf node, not from the root node. Initial search space is restricted within small limit around the leaf node and the recursive depth-first tentative search is excluded. Therefore, the length of the node traversal path can be shortened. Second, we developed several techniques of what and how information is cached and reused. The indexing sequence of data can be good information, as well as the data itself. Generally speaking, data are stored in consecutive order. So the indexing data can be similar to (i) the previous indexing data , (ii) the same indexing data in another data set, and (iii) even the NNS result of the previous iteration in the Iterative Closest Point algorithm. Furthermore, we introduce a new method to apply the proposed search algorithm to even randomly ...

New phthalocyanine (Pc) derivatives that include the alkyl group in ligand were synthesized based on three core metals such as zinc (Zn), copper (Cu), and cobalt (Co). Electrochemical behaviors and optical properties of the new phthalocyanine derivatives with ligand and different core metal were investigated by using cyclic voltammetry, UV-Visible (UV-Vis) spectroscopy and photoluminescence (PL) spectroscopy. In UV-Vis data, maximum values of 2H, Co, Cu, and Zn complexes were 708 nm and 677 nm, 686 nm, 684 nm, respectively.

We characterized the electrical properties of ambipolar polymer field-effect transistors (PFETs) based on the low-band-gap polymer, pNAPDO-DPP-EH. The polymer consisted of electron-rich 2,6-di(thienyl)naphthalene units with decyloxy chains (NAPDO) and electron-deficient diketopyrrolopyrrole units with 2-ethylhexyl chains (DPP-EH). The as-spun pNAPDO-DPP-EH PFET device exhibited ambipolar transport properties with a hole mobility of 3.64 × 10–3 cm2/(V s) and an electron mobility of 0.37 × 10–3 cm2/(V s). Thermal annealing of the polymer film resulted in a dramatic increase in the carrier mobility. Annealing at 200 °C yielded hole and electron mobilities of 0.078 and 0.002 cm2/(V s), respectively. The mechanism by which the mobility had improved was investigated via grazing incidence X-ray diffraction studies, atomic force microscopy, and temperature-dependent transport measurements. These results indicated that thermal annealing improved the polymer film crystallinity and promoted the formation of a longer...

In previous work, we have reported that a P3HT:PCBM-based organic photovoltaic cell using a thermally evaporated DMDCNQI buffer layer shows a high power conversion efficiency. In the present work, we have fabricated organic photovoltaic cells consisting of ITO/PEDOT:PSS/P3HT:PCBM:DMDCNQI/DMDCNQI/Al using an all-solution process. A thin, uniform DMDCNQI film was obtained in a methanol solution with high solubility and low viscosity. The prepared device shows a high power conversion efficiency of 2.9%. In particular, a maximum external quantum efficiency of 81% was obtained.

In this paper, a method of combining numerical analyses and experimental tests is used to evaluate fracture toughness of copper thin films of 15 �m thickness. Far-field loadings of a global-local finite element model are inversely estimated by matching crack opening profiles in experiments with numerical results. The fracture toughness is then evaluated using the J-integral for cracks in thin films under far-field loadings. In experiments, Cu thin films attached to Aluminum sheets are loaded indirectly, and crack opening profiles are observed by microscope camera. Stress versus strain curves of Cu thin films are obtained through micro-tensile tests, and the grain size of Cu thin films is observed by TEM analysis. The results show that the fracture toughness of Cu thin films with 500 nm ~ 1 �m sized grains is 6,962 J/m 2 .

Calcium intake has been insufficient in all age groups in previous Korean national surveys. This study was conducted to investigate calcium intake in Korean and American populations at different ages. We analyzed two national survey data: the 2007~2009 Korean National Health and Nutrition Examination Survey (KNHANES) and the 2007~2008 National Health and Nutrition Examination Survey (NHANES). Statistically, survey procedures were applied using the weight, cluster, and strata variables. The mean calcium intake of Koreans at ages of 1~2 y, 3~5 y, 6~11 y, 12~18 y, 19~64 y, and 65+y was lower than American populations at those ages. The sufficient proportions based on Korean Estimated Average Requirement (EAR) of 1~2 y, 3~5 y, 6~11 y, 12~18 y, 19~64 y, and 65+y in Koreans were 45.5%, 33.1%, 24.3%, 16.6%, 32.7%, and 19.0%. While the sufficient rates based on American EAR of 1~3 y, 4~8 y, 9~13 y, 14~18 y, 19~30 y, 31~50 y, 51~70 y, and 71+y in US population were 88.5%, 54.4%, 35.2%, 35.8%, 55.3%, 55.2%, 40.6%, and 24.5%. Overall, the major foods contributing to calcium intakes in Koreans were milk, baechukimchi, and anchovies, whereas, milk products, pasta, or bread were major contributions to calcium in American populations. The calcium supplement intakes in the American population were 5.5 mg (1~2 y), 15.5 mg (3~5 y), 13.9 mg (6~11 y), 35.7 mg (12~18 y), 150.3 mg (19~64 y) and 334.4 mg ( y). These results suggest that Korean adolescents and older adults are the most insufficient in dietary calcium intakes among Koreans. In order to accurately estimate calcium intakes in Korean populations, calcium supplements and calcium-fortified foods should be considered.

Three different new hole transport compounds, namely,2-[1-{4-(N,N-diphenylamino) phenyl}-3,4,5,6-tetraphenylbenzene-2-yl]5-N,N-diphenylaminopyridine(DPAP-TB), 2-[1-{4-(N-phenylnaphthalene-1-amino)phenyl}-3,4,5,6-tetraphenylbenzene-2-yl]5- (N-phenylnaphthalen-1-amino)pyridine(1-PNAP-TB) and 2-[1{4-(N-phenylnaphthal- en-1-amino)phenyl}-3,4-,5,6-tetraphenylbenzene-2-yl]-5-(N-phenylnaphthalen-2-amino)pyridine(2-PNAP-TB) were synthesized. Optical and electronic properties were examined by UV-Visible absorption spectrum and cyclic voltammetry. Luminance efficiencies and external quantum efficiencies of DPAP-TB, 1-PNAP-TB and 2-PNAP-TB were 3.72, 2.82, 3.30 cd/A, and 1.29, 0.97, 1.12% at 10 mA/cm2, respectively. Synthesized materials exhibited high Tg in the range of 118 to 133°C. These values are higher than that of NPB which is commonly used as a hole transporting material.

Arsenic (As) is widely distributed in the environment, and humans can be exposed to As from various sources such as air, water, soil, and food. This study was performed to evaluate the As exposure levels in Korean adults by measuring total As in urine and its relation with the consumption of seafood, a favorite food in Korea. A total of 2077 adults were the study subjects; they ranged in age from 19 to 83, and they were recruited by probability sampling stratified by area, sex, and age. None of the subjects had been exposed to As occupationally. We collected information about the demographic characteristics, lifestyles, and food consumption of study subjects using a questionnaire and followed urine sampling. Diet was assessed in individual interviews using the 24-h recall method. Total As in urine was analyzed using inductively coupled plasma mass spectrometry (PerkinElmer NEXION 300S; Concord, Ontario, Canada). The geometric mean concentration of total As in urine was observed to be 97.6 µg/L and was higher in males (103.9 µg/L) than in females (93.0 µg/L). Total As levels in urine were affected by sex, age, seafood intake, and geographic location. In this study, total As in urine was positively correlated with fish and shellfish consumption, and was mainly determined by As intake through fish and shellfish/grains/flavors. These findings suggest that seafood consumption might be a major contributor to urinary As levels in Korean adults.

In this paper, we focused on designing a semi-rotation invariant feature descriptors for classification problem. We proposed hierarchical Zernike moments architecture which is combination of original Zernike moments, the local receptive field concept and shared weights concept from convolution neural network. The descriptors which are output of the architecture have improved classification performance while maintaining rotation invariant property within semi-rotation region. Experimental results for classifying designed descriptors, extracted from semi-rotated MNIST dataset, with multi-layer perceptron demonstrate the effectiveness of the proposed method compared with other methods, such as original Zernike moments and convolution neural network.

This paper presents a fast algorithmic method to train convolutional neural network (CNN) classifiers through extreme learning which has been verified on popular datasets on classification and pedestrian detection. CNN has been one of the best classifiers for images and object recognition. However, the Backpropagation (BP) algorithm, mostly used for training CNN, suffers from slow learning, local minimum, and poor generalization. To solve these problems, a novel architecture called CNN-ELM has been proposed here. Its core architecture is based on a local image (local receptive field) version of the ELM (Extreme Learning Machine) adopting random feature learning. Using MATLAB 2015a, classification experiments using the raw image data as input, show a comparable or mostly better classification performance compared to the BP trained CNN, with its training speed up to 200 times faster on MNIST, NORB, and CIFAR-10 datasets. Pedestrian detection experiments using INRIA datasets also exhibits much faster training than the BP trained CNN without sacrificing detection performance.

As technology node has been shrinking for bit growth, various technologies have been developed for high productivity. Nevertheless, lithography technology is close to its limit. In order to overcome these limits, EUV(Extreme Ultraviolet Lithography) and DSA(Directed Self-Assembly) are being developed, but there still exists problems for mass production. Currently, all lithography technology developments focus on solving the problems related to fine patterning and widening process window. One of the technologies is NTD(Negative Tone Development) which uses inverse development compared to PTD(Positive Tone Development). The exposed area is eliminated by positive developer in PTD, whereas the exposed area is remained in NTD. It is well known that NTD has better characteristics compared to PTD in terms of DOF(Depth of Focus) margin, MEEF(Mask Error Enhancement Factor), and LER(Line End Roughness) for both small contact holes and isolated spaces [1]. Contact hole patterning is especially more difficult than space patterning because of the lower image contrast and smaller process window [2]. Thus, we have focused on the trend of both NTD and PTD contact hole patterns in various environments. We have analyzed optical performance of both NTD and PTD according to size and pitch by SMO(Source Mask Optimization) software. Moreover, the simulation result of NTD process was compared with the NTD wafer level performance and the process window variation of NTD was characterized through both results. This result will be a good guideline to avoid DoF loss when using NTD process for contact layers with various contact types. In this paper, we studied the impact of different sources on various combinations of pattern sizes and pitches while estimating DOF trends aside from source and pattern types.

We report high-performance of ambipolar organic field-effect transistors (FETs) based on the low band gap copolymers of pDPPT2NAP-HD and pDPPT2NAP-OD. The polymers are composed of electron-rich 2,6-di(thienyl)naphthalene (T2NAP) and electron-deficient diketopyrrolopyrrole (DPP) units with branched alkyl chains of 2-hexyldecyl (HD) or 2-octyldodecyl (OD). The polymers were polymerized via Suzuki coupling, yielding optical band gaps of ∼1.4 eV. In the transistor performance test, we observed good ambipolar transport behavior in both polymer films, and pDPPT2NAP-OD displayed hole and electron mobilities 1 order of magnitude higher than the corresponding properties of pDPPT2NAP-HD. Thermal annealing of the polymer films increased the carrier mobilities. Annealing at 150 °C provided optimal conditions yielding saturated film crystallinity and maximized carrier mobility. The highest hole and electron mobilities achieved in these polymers were 1.3 and 0.1 cm2/(V s), respectively, obtained from pDPPT2NAP-OD. The ...

High on-off ratio, low turn-on voltage and fast response time are most critical issues in the research and development of organic transistor. In the present work, we have fabricated vertical type organic transistor using 2,8-difluoro-indeno[1,2-b]fluorine-6,12-dione (IF-dione-F) as an organic active semiconductor and DMDCNQI as a n type buffer material. IF-dione-F shows n-type semiconductor property and relatively high electron mobility. The organic light emitting transistor (OLET) configuration is ITO (drain)/PEDOT:PSS/MEH-PPV/IF-dione-F/Metal (gate)/IF-dione-F/DMDCNQI/Metal (source). The characteristics of OLET were investigated from the measurements of current-radiance voltage characteristics, electron mobility and external quantum efficiency

Cardiovascular mortality has been shown to increase in the winter. However, it is unclear whether cold temperature affects indicators known as cardiovascular markers. We evaluated the association between ambient temperature and cardiovascular markers using data collected retrospectively from 55,567 adults who had visited a health check-up clinic between 1995 and 2008. Non-parametric smoothing regressions were fitted to determine the shapes of association between temperature and cardiovascular markers such as blood pressure, lipid profiles, platelet count, and high sensitivity C-reactive protein (hsCRP). Mixed effect model was used to investigate the significance of the relationship between temperature and cardiovascular markers. Decreased ambient temperature was associated with an increase in systolic and diastolic blood pressures, platelet count and serum low density lipoprotein-cholesterol concentration. In contrast, high density lipoprotein-cholesterol level declined with decreasing temperature. The hsCRP level increased with decreasing temperature in the minimum temperatures below 0°C, but revealed a reverse association above. Our study suggests that excess cardiovascular mortality in cold weather might be associated with temperature-related variations of cardiovascular markers.

High quality graphene sheets were produced from graphite by liquid phase exfoliation using N -methyl-2-pyrrolidone (NMP) and a subsequent thermal treatment to enhance the exfoliation. The exfoliation was enhanced by treatment with organic solvent and high thermal expansion producing high yields of the high-quality and defect-free graphene sheets. The graphene was successfully deposited on a flexible and transparent polymer film using the vacuum filtration method. SEM images of thin films of graphene treated at 800 °C showed uniform structure with no defects commonly found in films made of graphene produced by other techniques. Thin films of graphene prepared at higher temperatures showed superior transmittance and conductivity. The sheet-resistance of the graphene film treated at 800 °C was 2.8 × 10 3 kΩ/□ with 80% transmittance.

HC-SCR was conducted over Co-Pt/ZSM5 catalyst coated over 200 cpsi cordierite in the condition of atomspheric pressure and 200℃-500℃. Weight ratio of Co/Pt determined from EDX analysis was 8/2, which was almost equal to the weight ratio at preparation step . XPS showed that nitrates within cobalt precursor and chlorine withn Pt precursor were removed. TEM result demonstrated that crystallite size of cobalt and Pt was under 5nm. Among these tested hydrocarbon reductants, isobutane (i-C4H10) showed the highest de-NOx yield of 80% under the condition of the mole ratio of reductant/NOx =1.0 at 180℃. De-NOx yield from HC-SCR was increased as the carbon number of hydrocarbon reductant was increased. The decrease of bonding energy between C and H of HC reductant played a role to increase of de-NOx yield, which indicated that the dissociation step of C-H bond of hydrocarbon molecule might be the rate determining step of HC-SCR. The increase of oxygen concentration in the feed resulted in the decrease of de-NOx yield but the increase of CO and N2O yield.

Unlike the defined role of angiotensin-converting enzyme ( ACE ) gene in adult hypertension, ACE gene did not show direct influence on childhood blood pressure (BP), rather, seemed to be related to childhood growth with age-dependent characteristics. Thus, we examined intermediate effects of postnatal growth between the ACE polymorphisms and BP. We analyzed data from 257 children born in 2001–04 at Ewha Womans University Hospital in Seoul, Korea, and followed them up until 3 years of age. Children with excessive adiposity had higher BP, as rapid growers did to no-change and decelerated growers. The ACE II genotype was associated with greater growth acceleration than the DD genotype ( II : 46.8% vs. DD : 23.9%), and with a higher BP. The interactions between ACE genotype and adiposity at age 3 were significant on the BP levels. The highest BP increase with the same degree of adiposity was observed in those with the II genotype [β (SE) for BMI: 1.9 (0.9), p = 0.04]; particularly, only rapid grown II carriers demonstrated statistical significance on this linear association. These results suggested that ACE polymorphisms and BP association are mediated by postnatal growth. Further studies are required to determine the age-specific ACE genetic effects and its undefined biological mechanism.

With the goal of developing an accurate and fast lane tracking system for the purpose of driver assistance, this paper proposes a vision-based fusion technique for lane tracking and forward vehicle detection to handle challenging conditions, i.e., lane occlusion by a forward vehicle, lane change, varying illumination, road traffic signs, and pitch motion, all of which often occur in real driving environments. First, our algorithm uses random sample consensus (RANSAC) and Kalman filtering to calculate the lane equation from the lane candidates found by template matching. Simple template matching and a combination of RANSAC and Kalman filtering makes calculating the lane equation as a hyperbola pair very quick and robust against varying illumination and discontinuities in the lane. Second, our algorithm uses a state transfer technique to maintain lane tracking continuously in spite of the lane changing situation. This reduces the computational time when dealing with the lane change because lane detection, which takes much more time than lane tracking, is not necessary with this algorithm. Third, false lane candidates from occlusions by frontal vehicles are eliminated using accurate regions of the forward vehicles from our improved forward vehicle detector. Fourth, our proposed method achieved robustness against road traffic signs and pitch motion using the adaptive region of interest and a constraint on the position of the vanishing point. Our algorithm was tested with image sequences from a real driving situation and demonstrated its robustness.

Various metals for the cathode electrode of organic electronic devices have been used in order to improve carrier injection and contact resistance etc. However, metal electrodes have some disadvantages such as rough surfaces, inadequate interfacial durability and unsuitable work functions. In the present work, we have fabricated an organic photovoltaic cell consisting of ITO/PEDOT:PSS/P3HT:PCBM/DMDCNQI/Al. The dimmethyldicyanoquinonediimine (DMDCNQI) compound was used as an organic n-type charge transfer complex between the cathode electrode and an organic active layer to improve contact resistance and electron transport ability. The prepared device shows a high short-circuit current density of 10.39 mA/cm2 and a maximum power conversion efficiency of 3.10%.

In this paper, we propose a robust fingertip extraction and extended Continuously Adaptive Mean Shift (CAMSHIFT) based robust hand gesture recognition for natural human-like HRI (Human-Robot Interaction). Firstly, for efficient and rapid hand detection, the hand candidate regions are segmented by the combination with robust skin color model and haar-like features based adaboost. Using the extracted hand candidate regions, we estimate the palm region and fingertip position from distance transformation based voting and geometrical feature of hands. From the hand orientation and palm center position, we find the optimal fingertip position and its orientation. Then using extended CAMSHIFT, we reliably track the 2D hand gesture trajectory with extracted fingertip. Finally, we applied the conditional density propagation (CONDENSATION) to recognize the pre-defined temporal motion trajectories. Experimental results show that the proposed algorithm not only rapidly extracts the hand region with accurately extracted fingertip and its angle but also robustly tracks the hand under different illumination, size and rotation conditions. Using these results, we successfully recognize the multiple hand gestures.

Penicillium mycotoxins are natural contaminants found in grains, crops, fruits, and fermented products, especially during post harvest as well as storage periods. Contamination by individual and combinations of these toxins is likely to compromise food quality and safety. In this study, the potential immunotoxicity of citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA) and penicillic acid (PA) was evaluated using a bovine macrophage cell line (BOMACs) by assessing their potential cytotoxicity and then their effects on cell proliferation. The BOMACs were exposed to a range of mycotoxin concentrations, and then to different mycotoxin combinations for 48 hrs. Some cytotoxicity was evident at concentrations greater than 2.4 � M for PAT, and 160 � M for PA, however, at the IC50 (concentration that inhibits 50% cell proliferation), no cytotoxicity was observed for either of these mycotoxins. The mycotoxin IC50s from most potent to least potent were 0.56 � M (PAT), 12.88 � M (OTA), 29.85 � M (PA), and 91.20 � M (CIT). Concentrations of MPA greater than 80 � M did not inhibit cell proliferation enough to calculate an IC50. Significant higher inhibition of cell proliferation was observed from the combinations of CIT+OTA, OTA+PAT, and OTA+PA compared to the effects of individual mycotoxins suggesting additive and in some cases synergistic activity between these paired mycotoxins.

We present a method of simultaneous localization and mapping (SLAM) in a large indoor environment using a Rao-Blackwellized particle filter (RBPF) along with a line segment as a landmark. To represent the environment in a compact form, we use only two end points of a line segment, thus reducing computational cost in modeling line segment uncertainty. With a modified scan point clustering method, the proposed adaptive iterative end point fitting contributes to the estimation of line parameters by considering noisy scan points near end points. Thus, by line segment matching the robot is localized well in a local frame. We also introduce an online and offline method of global line merging, which provides a more compact map by removing spurious lines and merging collinear lines. Each of our approaches is efficiently integrated into the proposed RBPF-SLAM framework. In experiments with well-known data sets, the proposed method provides reliable SLAM and compact map representation even in a cluttered environment.

Organic photovoltaic cells consisting of ITO/PEDOT-PSS/P3HT:PCBM/TiO(x)/DMDCNQI/Al have been fabricated by using dip-coated DMDCNQI layer as a cathode buffer material. We have investigated the physical effects of charge transfer complex and wettability of DMDCNQI between TiO(x)/P3HT:PCBM layer and Al cathode electrode on the performance of organic photovoltaic cell. The photovoltaic cell fabricated with a dip-coated DMDCNQI layer exhibited almost similar performance compared to the device using conventional evaporated DMDCNQI layer. Especially, the power conversion efficiency of the prepared organic photovoltaic cell using TiO(x)/DMDCNQI layer was improved to 3.1%, which is mainly due to the decrease in the low contact resistance of organic-metal interface.

There are two winding methods for the interior permanent-magnet synchronous motor for vehicle traction: concentrated winding and distributed winding. Both have merits and demerits, and both influences the motor's performance. In this paper, designs of concentrated- and distributed-winding motors with the same capacities are presented, and each motor's characteristics were analyzed using the finite-element method.

Birth weight is a strong determinant of attained weight at early ages. Until now, many studies have reported that low birth weight corresponds with high mercury levels. However, the relationship between mercury exposure and attained weight of infant has not been well studied. Therefore, the aim of the present study was to assess the degree of prenatal exposure to mercury by measuring the total mercury levels in maternal and cord blood, and examine the relationship between the mercury level during pregnancy and the attained weight of infant during the first 24 months of life. The prospective cohort study of Mothers and Children's Environmental Health (MOCEH) was built up in 2006, and 921 mother-infant pairs were recruited. Information on the socio-demographic characteristics, health behavior and environmental exposure were collected from an interview with trained nurses. After delivery, infants and mothers were followed up at 6, 12 and 24 months and the weights of the infants were measured. The mercury concentrations in the late maternal blood (β=-0.19. p=0.05) and cord blood (β=-0.36. p=0.01) were negatively associated with the infants' attained weight over the first 24 months of age. The infants' attained weight in the small for their gestational age (SGA) group was lower than the normal birth weight group at the highest quartile of the mercury level. Therefore, efforts should be made to reduce the mercury level in the maternal blood at late pregnancy and cord blood. Further research on the possible harmful effects of prenatal mercury exposure on postnatal growth is recommended.

Nanopore generation could be accomplished in thin films of fully alicyclic polyimides derived from an alicyclic dianhydride and diamines. A silylation method for the alicyclic diamines was used to synthesize high molecular weight alicyclic polyimides. Triblock copolyimides were prepared using N-silylated alicyclic diamines, alicyclic dianhydride, and a thermally labile polymer. Nanoporous films of fully alicyclic polyimides were prepared through heating of the copolyimide films to induce thermal degradation of the labile block. Open image in new window

Carney complex (CNC) is an autosomal dominant hereditary or sporadic multiple neoplastic syndrome that shows variable clinical symptoms. Generally, CNC appears as skin pigmentation, cardiac or cutaneous myxomas, and multiple endocrine tumours. We performed an extensive evaluation of 9 individuals within 1 family in whom CNC was suspected. Among them, 5 had CNC with various clinical manifestations. We also performed mutational analysis of suspected genes in these patients. Although all patients were members of the same family, variable CNC-related manifestations were observed in each patient. An analysis showed a novel deletion mutation (c.537delA) in exon 6 of the PRKAR1A gene in the patients. Based on our results, the patients were determined to have CNC type I. This is the first such mutational report in Korea.

We developed high-performance stable n-type organic field-effect transistors (OFETs) using indenofluorenediones with different numbers of fluorine substituents (MonoF-IF-dione, DiF-IF-dione, and TriF-IF-dione). Top-contact OFETs were fabricated via the vacuum deposition of indenofluorenediones as the semiconducting channel material on polystyrene-treated SiO2/Si substrates. TriF-IF-dione FETs with Au source/drain contacts exhibited good device performances, with a field-effect mobility of 0.16 cm2/(V s), an on/off current ratio of 106, and a threshold voltage of 9.2 V. We found that the electrical stability for OFETs based on indenofluorenedione improved with the number of fluorine substituents, which was attributed to higher activation energies for charge trap creation. Moreover, the TriF-IF-dione FETs yielded excellent environmental stability properties, because the LUMO energy levels were relatively low, compared with those of the MonoF-IF-dione FETs.

The purpose of diet-quality indices is to assess and guide individual dietary intake for the promotion of health and prevention of disease, and food based dietary-quality indices need to be applied by using each country's own unique diet. We assessed the relationships between relatively simple dietary quality scores modified for a Korean diet, such as the Recommended Food Score (RFS) and alternate Mediterranean Diet Score (aMDS), and oxidative stress biomarkers in Korean adults. A total of 976 adults were recruited for the Biomarker Monitoring for Environmental Health Study between April and December 2005 in Seoul and Incheon, Korea. RFS and aMDS were calculated by using a food-frequency questionnaire. We used regression analyses to assess the associations between diet quality scores and urinary malondialdehyde (MDA) and 8-hydroxy-2′-deoxyguanosine (8-OHdG). RFS and aMDS were negatively associated with urinary MDA concentrations (P=0.032 for RFS, P=0.043 for aMDS), but not with 8-OHdG after adjusted for potential covariates. After stratified analyses by sex, negative associations between the both scores and urinary MDA concentrations were not significant in both men and women. There were no significant associations of RFS and aMDS with urinary 8-OHdG concentrations. Higher RFS and aMDS scores were related to lower oxidative stress. Therefore, good quality of diet may be useful in reducing oxidative stress.

Background: Emergent conversion to an on-pump procedure during an off-pump coronary artery bypass surgery (OPCAB) due to hemodynamic instability is associated with increased morbidity and mortality. The aim of this study was to evaluate the predictors of hemodynamic instability associated with mechanical heart displacement during OPCAB and the fate of these patients. Methods: Data of 494 patients who underwent elective, isolated OPCAB between December 2006 and April 2010 were reviewed. Hemodynamic instability was defined as mixed venous oxygen saturation (SvO2)

High voltage cryogenic insulation issues need to be addressed in order to promote the commercialization of high temperature superconducting (HTS) equipment. One of the critical components for superconducting devices is the bushing whose role is to safely supply high current to the device. Due to a steep temperature gradient, commercial bushings which have been insulated with SF6 gas could not be directly applied to cryogenic equipment due to liquefaction of SF6 in the cryogenic environment; therefore, alternative suitable structure and insulation methods should be developed. As a fundamental step in the development of the optimum bushings for HTS devices, the breakdown characteristics of liquid nitrogen mixed with liquefied insulating gases such as N2, SF6 and CF4 have been investigated. In particular, we noted the insulation characteristics of CF4 gas whose liquefication temperature is much higher than SF6 gas. Thus, in order to investigate the possibility of substituting CF4 gas for SF6 gas for the bushings of HTS electrical equipment, impulse tests, AC withstanding voltage tests, and partial discharge (PD) tests have been performed. As a result of these tests, it was shown that mixtures of liquefied insulating gases have a much higher breakdown voltage compared to pure liquid nitrogen. Especially in a cryogenic environment, the usage of SF6 gas should be evaluated due to freezing effects. On the other hand, CF4 gas has shown excellent insulation properties even in a cryogenic environment and could be utilized as an insulation gas for high voltage bushings of HTS electrical equipment.

During prenatal development, the nervous system may be more susceptible to environmental toxicants, such as secondhand smoke. The authors assessed the effects of prenatal and postnatal secondhand smoke exposure on the neurodevelopment of 6-month infants. The subjects were 414 mother and infant pairs with no medical problems, taken from the Mothers' and Children's Environmental Health study. Prenatal and postnatal exposures to secondhand smoke were determined using maternal self-reports. Examiners, unaware of exposure history, assessed the infants at 6 months of age using the Bayley Scales of Infant Development. Bayley scores were compared for secondhand smoke exposed and unexposed groups after adjusting for potential confounders. Multiple logistic regression analysis was carried out to estimate the risk of developmental delay posed by SHS exposure. The multivariate model included residential area, maternal age, pre-pregnancy body mass index, education, income, infant sex, parity, birth weight, and type of feeding. After adjusting for covariates, secondhand smoke exposure during pregnancy was found to be related to a decrease in mental developmental index score, but not to a decrease in psychomotor developmental index score. In addition, secondhand smoke exposure during pregnancy was found to increase the risk of developmental delay (mental developmental index score ≤85) at 6 months. This study suggests that the infants of non-smoking women exposed to secondhand smoke are at risk of neurodevelopmental delay.