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Formation of intermetallic compounds (IMCs) in solder joints is closely associated with the mechanical reliability of the system. Though internal voids formed in Ni/Sn solder joints are known to be related to the formation of Ni 3 Sn 4 IMC, a detailed study on the mechanical reliability has not yet been reported. In this study, the mechanical reliability of Ni/Sn joints was investigated using two different soldering systems: Ni/Ag-Ag/Sn/Ni bilayers and Ni/Sn/Ag-Ag/Sn/Ni sandwich structures. The failure mode was found to be closely related to the formation and growth of an Ag 3 Sn phase. Filling of the voids with Ag 3 Sn IMC resulted in maximum shear strength, with a failure locus through Ni 3 Sn 4 and Ag 3 Sn. However, formation of a large amount of Ag 3 Sn decreased the shear strength once again.

The purpose of the present study was to investigate the prevalence and incidence of gout in Korea and predict the future prevalence and incidence of gout. Data were collected from the national health claims database. Patients who had at least one claim for gout between 2007 and 2015 were included in the study. The prevalence of gout from 2007 to 2015 and the incidence of gout from 2009 to 2015 were determined. We estimated sex- and age-specific prevalence and incidence of gout during the period. The prevalence and incidence of gout were predicted using time series analysis. The prevalence of gout (95% CI) increased from 3.49 (3.48-3.51) per 1000 persons in 2007 to 7.58 (7.55-7.60) per 1000 persons in 2015. The incidence of gout (95% CI) was 1.52 (1.51-1.53) in 2009 and rose to 1.94 (1.93-1.95) per 1000 persons in 2015. The prevalence and incidence of gout were higher in men than in women. The older population had a higher prevalence and incidence than the younger population. The increase in prevalence was higher in the older population than the younger population, whereas the increase in incidence was higher in the younger population than the older population. The predicted prevalence and incidence of gout (95% CI) in 2025 were 16.59 (15.85-17.34) per 1000 persons and 3.81 (3.14-4.47) per 1000 persons. The prevalence and incidence of gout increased in Korea between 2007 and 2015. Men and the older population had a higher prevalence and incidence of gout compared to women and the younger population. However, the incidence of gout in the younger population has increased rapidly in recent years.

We report a large reduction in contact resistance between stretchable carbon nanotube/silicone rubber composites and silver electrodes by a chemical surface treatment, accompanied by an enhancement in the electrical conductivity of the composites. The reactive solvent, trifluoroacetic acid, works for the purpose. In addition, the treatment makes a uniform etching in a micro level with little sacrifice in surface roughness of the nanocomposites. The electrical conductivity of 1.0 wt% nanotube composite was enhanced approximately two-fold and three-fold by ten- and thirty-second treatment, which was induced by the reduction in the contact resistance to one half of an original value. It is meaningful that our finding can be an approach to reduce the nanoparticle loading while keeping electrical conductivity in a high level, which can be crucial for securing flexibility or stretchability in a viewpoint that the elongation is inversely proportional to the conductive particle loading.

We report enhanced dispersion conditions and electrical properties of multi-walled carbon nanotube (MWCNT) composites through the use of turbulent Taylor-Couette flow. The vortex flow, which is created in a cavity between concentric inner rotating and outer stationary cylinders, provided a uniform dispersion of MWCNTs in a polymer matrix through debundling highly entangled carbon nanotubes. Compared with a three-roll milling process that can apply mechanical shear forces to bundles of MWCNTs, the turbulent Taylor-Couette process generates fluidic shear forces that can more effectively exfoliate MWCNTs, particularly for high MWCNT concentrations. This was validated by the high electrical conductivity that reached 1640 S/m for uniformly dispersed carbon nanotubes in a silicone polymer matrix (at 21.8 Vol% of MWCNT). In view of their high electrical conductivity and uniform dispersion, the MWCNT composites can be promising for rapid electric heating elements.

The aim of this study was to prepare solid dispersion of nimodipine (NMD) by solvent evaporation method to overcome the poor water solubility of NMD, and to formulate controlled-release (CR) tablets containing the NMD solid dispersion. NMD is a dihydropyridine calcium-channel antagonist that is practically insoluble in water. Owing to the short half-life of the drug in the plasma, NMD immediate-release tablets should be administered frequently for the treatment and prevention of ischemic disorders following aneurysmal subarachnoid hemorrhage. In this study, solid dispersion technique was applied to increase the low solubility of NMD. Carriers for solid dispersions were prepared with different kinds of hydrophilic polymers. Kinetic solubility studies were performed for the prepared solid dispersions, using sodium acetate buffer (pH 4.5). Solid dispersions were then characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier transform infrared spectrometry (FT-IR). CR tablets containing the NMD-PVP K30 solid dispersions were designed to reduce the dosing interval and increase patient compliance. Hydroxypropyl methylcelluloses (HPMC) were used as release-modifiers, and lactose anhydrous as a diluent.

We present a novel hydrogel-based photocatalyst that contains TiO2 nanoparticles (NPs) uniformly dispersed in an agarose hydrogel matrix. The preparation of the TiO2/agarose hybrid gel photocatalyst was based on the gelation of agarose in the presence of well-dispersed TiO2 NPs in hot water. TiO2 NPs were homogeneously distributed in the agarose gel as characterized by Fourier transform infrared spectroscopy (FT-IR) analysis. It was found that the size, uniformity, and concentration of the hybrid gel as well as the contents of constituent ingredients have significant effects on the photocatalytic activity. The smaller and uniform size of the hybrid gel at an appropriate concentration exhibited superior photocatalytic performance in both photodegradation of methylene blue (MB) under UV light and TiO2 leakage. In the moderate concentration range of TiO2 and agarose, the degradation rate of MB increased upon increasing the TiO2 content or decreasing the agarose concentration. Under the optimized conditions, our hybrid gel showed excellent recycling performance over repeated use. Furthermore, we demonstrate the additional excellent features of our hybrid gel, which are: i) regeneration of pure TiO2 NPs and ii) thermal reconstruction of the hybrid gel. During the recycling, the TiO2 NPs initially immobilized in the hydrogel could be recovered through the programmed heating and separation techniques. Also, our hybrid gel could be easily reshaped into a new hydrogel with a desired architecture in terms of its size and shape. These unprecedented properties make our hybrid gel a smart and cost-effective new promising material for use in practical waste/water treatment.

To guarantee long lifetime of light emitting diodes (LEDs), thermal reliability of LED packages should be secured with suitable die-attaching materials. Die-attaching materials are important for the interconnection between optical devices and substrates, as they not only provide electrical transmission but also the emission of thermal budget generated under the operation of the devices. In this study, the joints with different die-attaching materials were closely investigated in conjunction with the optical performance of LED packages. Thermal reliability of the joints was quantitatively analyzed by estimating the thermal resistances of the metallic and intermetallic layers incorporating the joints. The experimental results revealed that insertion of nano-Ag paste between eutectic Au-Sn and Ag finish significantly improved heat emission by effectively suppressing thermal resistance of eutectic Au-Sn layer. However, to ensure long-term reliability, complete removal of numerous nano-voids among Ag nanoparticles should be accomplished to prevent accumulation of thermal budget.

Over the past decade, nanostructuring has become the core of thermoelectric (TE) material research because it creates numerous internal interfaces that provide an effective way to tune the electrical and/or thermal properties of TE materials. Herein, we report a synthesis of interface-engineered BiSbTe nanostructured TE materials by introducing chemically synthesized molecular Ten2− polyanions into BiSbTe particles, from which BiSbTe nanostructured materials with high-density Te interfacial layers are prepared in thin films and sintered pellets. These Te layers form the contact potential well at the BiSbTe-Te junction to realize energy dependent carrier scattering and scatter phonons effectively, thus resulting in simultaneous improvement in the electrical and thermal properties to increase the ZT value well above 1.3 ± 0.14 that is increased by 40% compared to bulk BiSbTe. The findings of current study can open up new chemical design spaces for interface-engineered electronic and TE materials.

For practical use of carbon nanotube (CNT) composites, especially in electronic applications, uniform dispersion of a high concentration of CNTs in a polymer matrix is a critical challenge. Three-roll milling is one of most reliable dispersion techniques. We investigate the effect of three-roll milling time on CNT length and the electrical properties of a CNT/polydimethylsiloxane composite film with 10 wt% CNTs. During the milling process, the CNT length is decreased from 10 to 1&ndash, 4 &mu, m by mechanical shear forces. The electrical conductivity increases after 1.5 min of milling owing to dispersion of the CNTs but decreases with increasing milling time owing to the decrease in the CNT length. Considering the changes in the electrical conductivity of the CNT composite and CNT length, we determined how to optimize the three-roll milling time to obtain a suitable dispersion state.

The uniform temperature distribution, one of the requirements for long-term durability, is essential for composite heaters. An analytical model for temperature distribution of a tube-type heater was derived, and it revealed that thickness uniformity is one order more important than intrinsic material properties such as density, heat capacity, and electrical conductivity of the heating tube. We introduced a circumferential shearing process to fabricate a flexible, seamless tube-type heating layer of carbon nanotube/silicone rubber composite with outstanding uniform distribution of thickness and temperature, which may be attributed to a shorter characteristic dimension in the circumferential direction than in the axial direction. The temperature uniformity was experimentally verified at various temperatures under heating. The difference in measured thickness and temperature in circumferential direction was within &plusmn, 1.3~3.0% (for tavg = 352.7 &mu, m) and &plusmn, 1.1% (for Tavg = 138.8 &deg, C), respectively, all over the heating tube. Therefore, the circumferential shearing process can be effective for cylindrical heaters, like a heating layer of a laser printer, which fuse toners onto papers during printing.

Hybrid carbon nanotube composites with two different types of fillers have attracted considerable attention for various advantages. The incorporation of micro-scale secondary fillers creates an excluded volume that leads to the increase in the electrical conductivity. By contrast, nano-scale secondary fillers shows a conflicting behavior of the decreased electrical conductivity with micro-scale secondary fillers. Although several attempts have been made in theoretical modeling of secondary-filler composites, the knowledge about how the electrical conductivity depends on the dimension of secondary fillers was not fully understood. This work aims at comprehensive understanding of the size effect of secondary particulate fillers on the electrical conductivity, via the combination of Voronoi geometry induced from Swiss cheese models and the underlying percolation theory. This indicates a transition in the impact of the excluded volume, i.e., the adjustment of the electrical conductivity was measured in cooperation with loading of second fillers with different sizes., Carbon nanotube–polymer composites containing secondary fillers are thought to possess enhanced electrical and mechanical properties. Here the authors combine Monte Carlo calculations with resistivity experiments to study the effect of filler size and shape on electrical conductivity.

We examine a two-stage litigation in which risk-averse litigants set contingent fees strategically for risk-neutral lawyers. In the first stage of the litigation, each litigant sets a fixed fee and a contingent fee for his lawyer. In the second stage, each lawyer exerts effort to win a lawsuit on behalf of the litigant. Employing the subgame-perfect equilibrium as a solution concept, we obtain the following results. First, if a litigant sets a higher rate of contingent fee, then the opponent follows suit and the contingent fee fraction increases in the difference in litigant’s utility between winning and losing the case. Second, changes in a litigant’s initial endowment have different effects on the contingent fee fraction depending upon litigant preferences, while an increase in the prize of the case always increases the contingent fee fraction regardless of litigant preferences.

Intersection Traffic Control (ITC) attracted extensive attention with the increase of traffic accidents and congestion that causes a huge social and economic losses. Also the topic on ITC has been widely studied by research communities. These studies fall into two categories: traffic signal scheduling and Autonomous Intersection management (AIM) based on Intersection Central Unit (ICU). The optimization of signal scheduling needs a lot of computations and the ICU based system is not flexible and not cost efficient. To solve this problem, the distributed AIM system should be the necessary requirement. However to our knowledge there is almost no work that has been devoted to distributed ITC for AV.

Intersection Traffic Control(ITC) attracted extensive attention with the increase of traffic accidents and congestion that causes a huge social and economic losses. Also the topic on ITC has been widely studied by research communities. These studies fall into two categories: traffic signal scheduling and Autonomous Intersection management(AIM) based on Intersection Central Unit(ICU). The optimization of signal scheduling needs a lot of computations and the ICU based system is not flexible and not cost efficient. To solve this problem, the distributed AIM system should be the necessary requirement. However to our knowledge there is almost no work that has been devoted to distributed ITC for AV. This paper proposes a token-based group mutual algorithm for the distributed AIM. We use a token as a privilege to pass cross zone(critical section in an intersection) and use one token. How to transfer the token among vehicles in a dynamic system in which a vehicle can not stay in the cross zone after it finish passing it is the core of our algorithm. We design the circulation of the token efficiently among vehicles and session declare concept to improve the flow of vehicles. The proposed algorithm can handle quite a big traffic volume well with decreased message complexity. It outperforms the reference algorithms in message complexity and presents better result in system throughput than traffic signal system. This paper also will vitalize the researches about the distributed AIC.

Six lactic acid bacteria (LAB) and four yeast strains were isolated from Pyeongchang spontaneous sourdough. In combination with the segregated Saccharomycopsis fibuligera and Saccharomyces cerevisiae, Pediococcus pentosaceus was employed for sourdough bread starters because of its antifungal action against Aspergillus flavus. The sourdough bread fermented with P. pentosaceus and S. cerevisiae displayed 56.4% ± 5.5% antifungal movement counter to A. flavus expansion at 96 h. The concentration of lactic and acetic acids in the sourdough bread was 4.5- and 1.6-folds above the control bread, respectively, contributing to the balanced sensory properties with a fermentation quotient (FQ) of 2.08–2.86. SPME- GC/MS newly distinguished twenty-two volatile compounds including six aldehydes, five alcohols, one phenol, three ketones, one acid, and six esters. The results suggest the P. pentosaceus and S. cerevisiae combination as promising sourdough starters for making enhanced quality bread free of preservatives.

Remission is a primary end point of in clinical practice and trials of treatments for rheumatoid arthritis (RA). The 2011 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria were developed to provide a consensus definition of remission. This study aimed to assess the concordance between the new remission criteria and the physician’s clinical judgment of remission and also to identify factors that affect the discordance between these two approaches. A total of 3,209 patients with RA were included from the KORean Observational Study Network for Arthritis (KORONA) database. The frequency of remission was evaluated based on each approach. The agreement between the results was estimated by Cohen’s kappa (κ). Patients with remission according to the 2011 ACR/EULAR criteria (i.e. the Boolean criteria) and/or physician judgment (n = 855) were divided into three groups: concordant remission, the Boolean criteria only, and physician judgment only. Multinomial logistic regression analysis was used to identify factors responsible for the assignment of patients with remission to one of the discordant groups rather than the concordant group. The remission rates using the Boolean criteria and physician judgment were 10.5% and 19.9%, respectively. The agreement between two approaches for remission was low (κ = 0.226) and the concordant remission rate was only 5.5% (n = 177). Pain affected classification in both discordant groups, whereas fatigue was associated with remission only by physician clinical judgment. The Boolean criteria were more stringent than clinical judgment. Patient subjective symptoms such as pain and fatigue were associated with discordance between the two approaches., Graphical Abstract

Negative temperature coefficient of resistance of a material can be a disadvantage in high temperature applications, causing a system to be thermally unstable as the temperature increases. We investigate the concept of excluded volume to suppress the negative temperature coefficient of resistance of a multi-walled carbon nanotube/silicone rubber composite. When micro- or nano-silica particles are incorporated to realize the segregated conductive network, the resistance-temperature dependence of the composite is suppressed in both the conductive polymer composite itself and a fuser unit for printers having the carbon nanotube composite as heating layer. It is believed that the effect of mechanical reinforcement and suppression in thermal expansion by the secondary particles are essential for suppressing the temperature dependence of resistance. This investigation on the excluded volume can be interpreted to offer a new perspective on nanomaterial-based thermistor technology.

We report a strategy toward the synthesis of colloidal nanocrystals capped with inorganic molybdenum and tungsten sulfide ligands. MoS4(2-) and WS4(2-) thiometalates were utilized to replace organic ligands capping a wide range of nanocrystals such as metals, semiconductors, and well-conserved primary properties of nanocrystals in polar media. Especially, MoS4(2-)- and WS4(2-)-capped CdSe nanocryatals showed the dramatic enhancement of photoluminescence properties by the photo-oxidation treatment, which originated from the preferential formation of MoSxOy layers on the CdSe surface. The highest quantum yield reached up to 51%. Furthermore, we studied the charge-transport properties of MoS4(2-)-capped PbS nanocryatals by the fabrication of a field-effect transistor and photodetectors. Finally, MoS4(2-)- and WS4(2-)-capped nanocrystals were used for the production of two-dimensional MoS2 and WS2 thin layers on nanostructures by heat treatment. Such versatility of these thiometalate ligands offers an additional degree of control over the functionality of nanocrystals for optoelectronic and catalytic applications.

In this paper, we propose an election protocol based on mobile ad-hoc network. In distributed systems, a group of computer should continue to do cooperation in order to finish some jobs. In such a system, an election protocol is especially practical and important elements to provide processes in a group with a consistent common knowledge about the membership of the group. Whenever a membership change occurs, processes should agree on which of them should do to accomplish an unfinished job or begins a new job. The problem of electing a leader is very same with the agreeing common predicate in a distributed system such as the consensus problem. Based on the termination detection protocol that is traditional one in asynchronous distributed systems, we present the new election protocol in distributed systems that are based on MANET, i.e. mobile ad hoc network.

We present a facile approach to making Al-Sb, carbon-modified (Al-Sb-C) nanocomposites for use as new anode materials in lithium-ion batteries (LIB). Alloying is achieved by one step synthesis using high energy mechanical milling (HEMM), producing nanometer-sized alloy particles of Sb-Al x C y -C. Based on electrochemical analyses, we determined that Sb acts as an active material, and both Al and carbon create a hybrid buffering matrix that mitigates the volume expansion of the active material during lithiation/delithiation to a greater degree than that by a pure metallic matrix (AlSb). In addition, we optimized the stoichiometric ratio of Al and Sb with regard to specific capacity and cycling performance. Of the ratios tested, a 1:1 molar ratio of Al and Sb exhibited the best cycling performance (302.5 mAh g −1 after 200 charge/discharge cycles). Although our Al-Sb-C composite had low initial coulombic efficiency (∼59%), recovery to ∼ 97% occurred within three cycles, indicating that initial side reactions are quickly reduced over the course of cycling. AlSb-C anodes also showed good rate capability and volumetric capacity. Overall, the new AlSb-C composite is a promising candidate for use as negative electrodes in lithium-ion batteries, providing an alternative to commercially available graphite electrodes.

Eutectic Au–Sn solder has widely been used for high temperature bonding since it enables fluxless soldering and provides mechanically stable solder joint. However, effect of multiple bonding process on the mechanical reliability has not been studied in detail. In this study, microstructure evolution of Au–Sn solder joint and its effect on mechanical reliability were systematically investigated. During the multiple reflow process, the eutectic phase gradually transformed into ζ phase, which resulted in loss of solderable area. The phenomenon turned out to be responsible for degradation of bonding strength of the solder joint.

In this study, the electrode performance of composite films composed of highly conductive multiwalled carbon nanotubes (MWCNTs) and poly(3,4-ethylenedioxythiophene) polymerized with poly(4-styrenesulfonate) (PEDOT:PSS) are improved with the use of HCl–methanol (HCl–met) treatment. The HCl–met treatment affects film properties, including surface morphology, optical transmittance, work function (Φ), and electrical conductivity, which are investigated using various kinds of MWCNT/PEDOT:PSS composite systems. As a result of the HCl–met treatment, all MWCNT/PEDOT:PSS films undergo considerable changes in molecular ratio and arrangement between PEDOT and PSS, but their MWCNTs have no chemical/structural transitions. This in turn enhances the electrical conductivity and catalytic activity of the MWCNT/PEDOT:PSS films without changing their other properties. Furthermore, because of these effects, the HCl–met treatment brings about noticeable enhancements in performance as the source/drain electrode in an organic ...

To identify the level of agreement between patients with rheumatoid arthritis (RA) and physicians in the global assessment of disease activity and to explore factors influencing their discordance.A total of 4368 patients with RA were analyzed from the KORean Observational study Network for Arthritis (KORONA) database. Patients were divided into four subgroups according to difference from their physicians in the assessment of disease activity by substracting physician's visual analog scale (VAS) from patient's VAS as follows: positive discordance group I (10 mm ≤ discordance25 mm), positive discordance group II (≥25 mm), concordance (|10| mm), and negative discordance (≤ -10mm). Multinomial logistic regression analysis was performed to identify factors associated with discordance.Only 1350 (29.2%) patients were classified in the concordance group. Positive discordance was found in 52.3% of the patients (n = 2425), with 33.7% (n = 1563) showing marked discordance (≥25 mm). The high disease activity (OR =1.41), gastrointestinal (GI) disease (OR =1.28), pain (OR =1.12), fatigue (OR =1.07) were consistently associated with positive discordance.More than half of patients with RA thought their disease more severe than their physicians. In addition to high disease activity, pain, fatigue, and sleep disturbance or GI disease were associated with the discordance between physicians and patients with RA.

This paper reports a new method to enable the normally-off operation of AlGaN/GaN heterojunction field-effect transistors (HFETs). A capacitor was connected to the gate input node of a normally-on AlGaN/GaN HFET with a Schottky gate where the Schottky gate acted as a clamping diode. The combination of the capacitor and Schottky gate functioned as a clamp circuit to downshift the input signal to enable the normally-off operation. The normally-off operation with a virtual threshold voltage of 5.3 V was successfully demonstrated with excellent dynamic switching characteristics.

Monolithically integrated devices are strongly desired in next generation power ICs to reduce the chip size and improve the efficiency and frequency response. Three examples of the embedment of different functional diode(s) into AlGaN/GaN heterojunction field-effect transistors are presented, which can minimize the parasitic effects caused by interconnection between devices.

In carbon nanotube (CNT) polymer composites, the small thermal capacitance of the polymer and high thermal conductivity of the CNTs enable rapid heating. Highly conducting polydimethylsiloxane (PDMS) nanotube composites with different aspect ratios of CNT were investigated to observe their electrical heating behavior. The electrical conductivity of the CNT/PDMS composite with higher ratio CNTs showed the conductivity up to two orders of magnitudes larger than the composites with lower aspect ratio CNTs. Moreover, the degree of negative temperature coefficient of resistance originating from the interconnection resistance between the CNTs could be dramatically increased by using higher aspect ratio CNTs.

This study conducts an experimental and theoretical investigation of the influence of a polyvinylpyrrolidone (PVP) capping layer on silver nanowire (AgNWs) networks. Through a washing method, a PVP layer on AgNWs was removed and the contact resistance (RC) between AgNWs was reduced, thereby obtaining a reduced sheet resistance (RS) of AgNW film. During the washing process, the thickness of the PVP layer decreased to 1 nm with an increasing number of washes, as demonstrated by a molecular dynamics simulation. In addition, the size of the change in RS resulting from the reduction in RC by the removal of PVP decreased as the areal coverage of NWs increased. In order to explain the results, Monte Carlo simulations were performed and the results show that the reduction in RC by the removal of PVP apparently reduces the value of RS more as the areal coverage of NWs decreases and the initial value of RC of the network increases. Saturation of the reduction in RS also occurs when the inherent resistance of AgNW (RNW) becomes dominant. Along with the electrical properties, improved transmittance and a reduction in haze were observed with the removal of PVP, and the results prove that RS can be reduced by reducing RC without impairing the optical properties of transparent conducting electrodes.

Small-scaled wind turbine is converted to mechanical power of windmill to electric power by generator. However almost all studies seems to have overlooked converting relation of mechanical & electric power. It the reason for was very difficult establishing wind turbine system. In this paper, it is define equation of converting relation of mechanical & electric power. And it is verified by experimental methods. Defined equation will be used in developing electric devices such as inverter and controller in wind turbines. In addition this method can be used in the fields that utilize the rotational power into electrical power through generator.

Shopping patterns are changing with the emergence of SNS. Recently, it is also interested in providing the information based on the users’ needs. Generally, the provided information is obtained from the history of users‘ simple browsing. Best selling hot item list is also provided in order to reflect the preferences of public users. However, the provided information is irrelevant to an individual preference. In this paper, we propose a method to utilize inner and outer SNS for analyzing public preferences about goods which are interested by individual users. The inner analyzing module collects and analyzes the preferences of community members about two goods designated by individual users. The outer analyzing module supports to analyze public preferences by using the tweeter SNS. The results of implementation show that it is possible to recommend goods based on the individual users’ preferences unlike the existing shopping mall. 키워드 : 니즈분석, 모바일 시스템, 사용자 지정 선호도, SNS Key word

Multiwalled nanotube (MWNT)/silicone composites having segregated MWNT network and micro-void structure were developed for wearable thermotherapy application. The nano-composites could be quickly fabricated from instant evaporation of aqueous medium during spray coating process. Fast electric heating behavior (4.8 °C/s) was demonstrated, in comparison with that (1.4 °C/s) of conventional silicone rubber composites having no void. Long-term stability was also verified with thermal aging and thermal cycling tests up to 100 h.

The key characteristics of bending sensors are piezoresistive effect, hysteresis, and durability. In this study, to investigate the influence of the aspect ratio and contents of multi-walled nanotubes (MWNTs) on the properties of bending sensors, MWNT/polydimethylsiloxane (PDMS) composites were fabricated with various aspect ratios and filler contents. The MWNTs were uniformly dispersed in the composites using the three-roll milling method. By increasing the bending angle gradually, the sensitivity of each composite was analyzed. Furthermore, discontinuous cyclic bending tests were conducted to investigate the piezoresistive effect and hysteresis. In addition, stable repeatability of the composites was confirmed through continuous cyclic bending tests. As a result, optimal aspect ratios and filler contents have been presented for application in bending sensors of MWNT composites.

Highly aligned multi-walled carbon nanotube (MWCNT) polymer composites were fabricated via a roll-to-roll milling process, the alignment of the MWCNTs could be controlled by varying the speed of the rotating rolls. The effect of MWCNT alignment on the polymer matrix was morphologically observed and quantitatively characterized using polarized Raman spectroscopy. To provide a more detailed comparison, MWCNT composites with alignment in the transverse direction and random alignment were fabricated and tested. Enhanced mechanical and electrical properties were obtained for the aligned MWCNT composite, which can be attributed to the efficient electrical network and load transfer, respectively. In addition, a cyclic stretching test was conducted to evaluate the piezo-resistive characteristics of the aligned MWCNT composites. The composites with an aligned filler configuration showed an exceptionally high degree of strain sensitivity compared to the other composites.

To develop a clinical practice guideline for vaccination in patients with autoimmune inflammatory rheumatic disease (AIIRD), the Korean College of Rheumatology and the Korean Society of Infectious Diseases developed a clinical practice guideline according to the clinical practice guideline development manual. Since vaccination is unlikely to cause AIIRD or worsen disease activities, required vaccinations are recommended. Once patients are diagnosed with AIIRD, treatment strategies should be established and, at the same time, monitor their vaccination history. It is recommended to administer vaccines when the disease enters the stabilized stage. Administering live attenuated vaccines in patients with AIIRD who are taking immunosuppressants should be avoided. Vaccination should be considered in patients with AIIRD, prior to initiating immunosuppressants. It is recommended to administer influenza, Streptococcus pneumoniae, hepatitis A, hepatitis B, herpes zoster, measles-mumps-rubella virus, human papillomavirus, and tetanus-diphtheria-pertussis vaccines in patients with AIIRD; such patients who planned to travel are generally recommended to be vaccinated at the recommended vaccine level of healthy adults. Those who live in a household with patients with AIIRD and their caregivers should also be vaccinated at levels that are generally recommended for healthy adults.

Frost presents a serious problem for the human environment, resulting in such phenomena as downed power lines, damaged crops and stalled aircraft. In addition, frost and ice accumulation significantly decrease the performance of ships, wind turbines, and HVAC systems with high failure risk. Super-hydrophobic (SH) surface can be an appropriate solution for frost problems, due to its anti-icing properties that can prevent ice nucleation on the surface. In addition, in the case of conducting SH surface using carbon nanotubes (CNTs) as a filler, it can form an excellent heating unit, owing to the resistive heating effect. The purpose of this study is to produce a large-area conducting SH film that can prevent ice nucleus and remove ice formation rapidly. High aspect ratio carbon nanotubes (CNTs) as a conducting filler and adhesive polymer resin as a binder were used to form coating layer. In addition, silica particles (~7 nm) were used to stabilize nano-size roughness of the SH surface. Wet and dry etching processes were used on the substrate to improve wettability and to produce organic functional groups. To evaluate the de-icing effect, the fabricated SH surface was rapidly heated to 150 °C by applying voltage.

Carbon nanotube (CNT) composites have been widely investigated for electric heating applications (such as water heater, de-icing unit, and patternable micro heaters) owing to their rapid heating, flexibility and light-weight properties. For practical use of CNT composite as heating element applications, the change of resistance with varying temperature must be interpreted. In this study, electric heating behavior of CNT/Nylon 6 composite film (10 wt%) and CNT/Polydimethylsiloxane (PDMS) composite film (10 wt%) were evaluated by measuring the change in normalized resistance under extreme temperature from -50 °C to 100 °C. While CNT/PDMS composite film showed 25% normalized resistance change from -50 °C to 100 °C, in the case of CNT/Nylon 6 composite film, only 10% normalized resistance change was shown. The difference of resistance change is attributed to the difference of the polymer's coefficient of thermal expansion (CTE), which is a crucial factor to consider in the design of CNT composites as a heater or heating sensor. CNT/Nylon 6 composite film is appropriate for flexible heating unit and de-icing application, due to the lower degree of resistance change than that of CNT/PDMS composite film. In addition, a thermal cycling test was conducted to determine the thermal stability and repeatability of CNT composites.

Intensity and acceleration characterise the contemporary dialogue between Europe and South Korea, with the EU–South Korea Free Trade Agreement (signed in 2011) setting the benchmark for relations which are expected to widen and deepen. This chapter hypothesises a set of influencing factors that shape EU images in South Korea based on the analysis of the Korean news media and perceptions among general public opinion towards the EU. These factors are grouped as: (1) those that exist exclusively in Korea; (2) those that are EU-specific; (3) global factors shaped by the international system; and (4) factors that are related to EU–Korea interaction. The dataset is derived from three reputable Korean newspapers (monitored in April 1–June 30, 2015) and a public opinion poll (1238 respondents surveyed in August 2015).

Wind-blown dust models use input data, including soil conditions and meteorology, to interpret the multi-step wind erosion process and predict the quantity of dust emission. Therefore, the accuracy of the wind-blown dust models is dependent on the accuracy of each input condition and the robustness of the model schemes for each elemental step of wind erosion. A thorough evaluation of a wind-blown model thus requires validation of the input conditions and the elemental model schemes. However, most model evaluations and intercomparisons have focused on the final output of the models, i.e., the vertical dust emission. Recently, a delicate set of measurement data for saltation flux and friction velocity was reported from the Japan-Australia Dust Experiment (JADE) Project, which enabled the step-by-step evaluation of wind-blown dust models up to the saltation step. When all the input parameters were provided from the observations, both the two widely used saltation schemes showed very good agreement with measurements, with the correlation coefficient and the agreement of index both being larger than 0.9, which demonstrated the strong robustness of the physical schemes for saltation. However, using the meteorology model to estimate the input conditions such as weather and soil conditions, considerably degraded the models&rsquo, performance. The critical reason for the model failure was determined to be the inaccuracy in the estimation of the threshold friction velocity (representing soil condition), followed by inaccurate estimation of surface wind speed. It was not possible to determine which of the two saltation schemes was superior, based on the present study results. Such differentiation will require further evaluation studies using more measurements of saltation flux and vertical dust emissions.

The change in acidity of pyrolysis bio-oil was investigated using the catalytic pyrolysis of cork oak over zirconia synthesized by supercritical hydrothermal synthesis using a fixed bed reactor. Catalytic pyrolysis over zirconia reduced the content of acetic acid considerably and showed high selectivity to ketones and high-value-added aromatic compounds.

Air pollution has a negative impact on human life around the world. Particularly, researches on PM, which is a harmful air pollution source, are being actively carried out these days. To help these environmental problems, we propose the system through this paper. The proposed system is a useful system for analyzing environmental problems related to air pollution. It uses various information collectively to generate high quality data for analysis. In addition, we analyzed the correlation between PM and vehicular traffic in the Daejeon area. As a result, we found that the speed of the vehicle has a greater effect on the road PM value than the number of vehicles.

Bilateral relations between the United Kingdom (UK) and Korea are driven by trade, the importance of which means a post-Brexit bilateral trade agreement is likely to be a priority for both sides. The European Union (EU) and Korea have already signed a comprehensive and groundbreaking agreement, so a new ‘cut and paste’ agreement between the UK and Korea might be considered a straightforward matter. But the UK’s departure from the EU will expose several complexities in the latter’s relationship with Korea, meaning in turn that developing a new UK-Korea bilateral relationship is likely to be complex and any new trade agreement between the two is unlikely to be as beneficial to UK interests as the current arrangements.

Enzyme technology has many potential applications in the baking industry because carbohydrate-active enzymes specifically react with carbohydrate components, such as starch, in complex food systems. Amylolytic enzymes are added to starch-based foods, such as baking products, to retain moisture more efficiently and to increase softness, freshness, and shelf life. The major reactions used to modify the structure of food starch include: (1) hydrolysis of α-1, 4 or α-1, 6 glycosidic linkages, (2) disproportionation by the transfer of glucan moieties, and (3) branching by formation of α-1, 6 glycosidic linkage. The catalytic reaction of a single enzyme or a mixture of more than two enzymes has been applied, generating novel starches, with chemical changes in the starch structure, in which the changes of molecular mass, branch chain length distribution, and the ratio of amylose to amylopectin may occur. These developments of enzyme technology highlight the potential to create various structured-starches for the food and baking industry.