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The strain generated by photoresponsive polymer actuators under external applied loads is a key performance parameter. Herein, we investigated the photogenerated strain under uniaxial loads in densely crosslinked azobenzene-incorporated liquid crystalline polymer (azo-LCP) actuators. Spectral analysis indicated that the liquid crystalline (LC) moieties and incorporated azobenzene moieties behave independently under load. The degree of LC mesogen distortions decreased as the applied load increased, whereas azobenzene isomerization showed high tolerance towards the external load. Such stress-response differences led to universal “two-stage” photogenerated strain behavior, with rapid decreases under low applied loads and steady linear decreases under relatively high loads. More importantly, we found that light intensity has little influence on important parameters such as the loading stage and actuator failure stress. However, these properties could be optimized by changing the crosslinking density (either azobenzene or side-chain LC concentration) in the polymeric network.

This paper presents a decentralized controller design for formation and traction control of multiple robots with collision avoidance. The proposed control design consists of two steps: formation control design with collision avoidance and traction control design for movement of robot formation along the desired trajectory. In the first step, a formation controller is designed based on the formation graph model of multiple robots and potential function approach. Then, the traction control input is derived in the second step by locating the virtual leader at the central position of robot formation which leads mobile robots to follow the assigned trajectory in formation. In this distributed control design, parameter uncertainty in kinematic system model is also accommodated by deriving an adaptive rule for estimation of uncertain system parameters. Together with the stability analysis of the proposed controller, simulation and experiment results verify the feasibility and effectiveness of the distributed controller for multi-robot coordination.

Although Streptococcus parauberis is the major bacterial pathogen affecting olive flounder, the translocation and dissemination of this pathogen in infected fish are not well understood. Therefore, we conducted real-time PCR and histopathologic examination to monitor the intensity of infection in multiple organs of the olive flounder after challenge with S. parauberis through subcutaneous injection. The bacterial burden in the fish kidney, when sampled at 0, 3, and 7 dpc, was 0, 6.2 ± 4.5 × 105, and 6.7 ± 5.5 × 106 CFU/100 mg of tissue, respectively, indicating that the infection progressed rapidly over time. Of the ten different tissues sampled, the heart and the brain were the major target organs of S. parauberis based on highest copy number as detected by our modified real-time PCR method. Histopathologic examination also showed that S. parauberis caused severe inflammation accompanied by leucocyte infiltration, connective tissue expansion, and a loss of cardiomyocytes in the brain and heart of fish sampled at dpc 7. However, the number of S. parauberis-positive fish at 3 dpc was much higher in the spleen (6/8 fish) than in the remaining organs, suggesting that the spleen is targeted in the early stages of infection relative to the heart (2/8 fish) or brain (3/8 fish). This study provides essential information for studies to find treatments for the effective elimination of S. parauberis in target organs (i.e., the brain and heart) of olive flounder.

Owing to the fact that thermal fatigue is a well-known damage mechanism in nuclear power plants, accurate stress and fatigue evaluation are highly important. Operating experience shows that the design condition is conservative compared to the actual one. Therefore, various fatigue monitoring methods have been extensively utilized to consider the actual operating data. However, defining the local temperature in the piping is difficult because temperature-measuring instruments are limited. The purpose of this paper is to define accurate local temperature in the piping and evaluate thermal stress using Green’s function (GF) by performing a series of computational fluid dynamics analyses considering the complex fluid conditions. Also, the thermal stress is determined by adopting GF and comparing it with that of the design condition. The fluid dynamics analysis result indicates that the fluid temperature slowly varies compared to the designed one even when the flow rate changes abruptly. In addition, the resulting thermal stress can significantly decrease when reflecting the actual temperature.

Steam generator is one of the major components in a nuclear power plant, and it consists of thousands of thin-walled tubes. The operating record of the steam generators has indicated that a number of axial cracks due to stress corrosion have been frequently detected in the tubes. Since the tubes are closely related to the safety and also the efficiency of a nuclear power plant, an establishment of the appropriate repair criterion for the defected tubes and its applications are necessary. The objective of this paper is to develop an accurate repair criterion for the tubes with axial cracks. To do this, a thorough review is performed on the key parameters affecting the tube integrity, and then the probabilistic integrity assessment is carried out by considering the various uncertainties. In addition, the sizes of critical crack are determined by comparing the burst pressure of the cracked tube with the required performance criterion. Based on this result, the new repair criterion for the axially cracked tubes is defined from the reasonably conservative value such that the required performance criterion in terms of the burst pressure is able to be met during the next operating period.

We found that the thermal conductivity of the polycarbonate (PC) composite filled with both 9.9 wt% expanded graphite (EG) and 0.1 wt% multi-walled carbon nanotube (MWCNT) fillers was synergistically improved by 49% compared to that of the PC composite filled with 10 wt% EG alone. In order to induce the optimal internal structure favorable for thermal conduction by enhancing the dispersion of the second MWCNT fillers, we applied a two-step melt-compounding to fabricate composites using a MWCNT masterbatch based on a polymerizable oligomer resin, cyclic butylene terephthalate (CBT), which is characterized by ultra-low viscosity and excellent impregnability during initial melting. Three-dimensional (3D) non-destructive characterization using X-ray micro computed tomography (micro-CT) was utilized to demonstrate the synergistic enhancement and to verify dispersion and 3D thermal network of the fillers in the composites accurately. The synergistic enhancement was significantly affected by the formation of the efficient thermally conductive pathways and dispersion of the second MWCNT fillers.

This paper suggests a simple method to solve the clock skew problem generated on two or several separate chips when voltage difference, or gradient, occurs between/among the chips. Generation and distribution of clock signals with minimum skews becomes a critical factor in overall system performance in today’s GHz operation speed. With a few connection lines, similar to Data Bus, between two chips, named CBL (Clock Bus Line), a multi-chip synchronization method is newly proposed and proved through simulations and TTL chip measurements. With 2% of supplied voltage differences in different chips, within 3% of the period clock skew is guaranteed in this new scheme. A feasible way of implementation of this CBL method in today’s integrated circuits is also described along with CMOS layout.

An 81-year-old male patient presented with complaint of a pulsating neck mass. The patient had a previous history of cervical lymphadenopathy by non-tuberculous mycobacterium infection. Rapid growth of the mass on admission and contrast enhanced computed tomography of the neck resulted in a diagnosis of non-tuberculous mycobacterium induced pseudoaneurysm. The patient underwent emergency open repair of the pseudoaneurysm. Pseudoaneurysm of the common carotid artery is regularly reported, but here we report a rare case of non-tuberculous mycobacterium induced pseudoaneurysm of the common carotid artery.

BACKGROUND In this study, we aimed to investigate the relationship between echocardiographic epicardial fat thickness (EFT), neutrophil to lymphocyte ratio (NLR; an important inflammatory marker), and diurnal blood pressure (BP) changes in patients with recently diagnosed essential hypertension. METHODS A total of 647 patients underwent echocardiography and 24 hours of ambulatory BP monitoring. EFT was measured by echocardiography, while NLR was measured by dividing the neutrophil count by the lymphocyte count. Patients were categorized into three groups according to BP pattern: the normotensive group, the dipper group, and the non-dipper group. RESULTS The mean EFT was highest in the non-dipper group (non-dipper group, 7.3 ± 3.0 mm; dipper group, 6.1 ± 2.0 mm; control group, 5.6 ± 2.0 mm; p < 0.001). NLR was also highest in the non-dipper group (non-dipper, 2.75 ± 2.81; dipper, 2.01 ± 1.32; control, 1.92 ± 1.11; p < 0.001). EFT was significantly correlated with age (r = 0.160, p < 0.001) and NLR (r = 0.353, p < 0.001). Furthermore, an EFT ≥ 7.0 mm was associated with the non-dipper BP pattern with 51.3% sensitivity and 71.6% specificity [95% confidence interval (CI) = 0.56-0.65, p < 0.001]. In a multivariate analysis, EFT [adjusted odds ratio (OR) = 3.99, 95% CI = 1.22-13.10, p = 0.022] and NLR (OR = 1.34, 95% CI = 1.05-1.71, p = 0.018) were independent parameters that distinguished a non-dipper pattern after adjustment for cardiovascular risk factors. CONCLUSION EFT and NLR are independently associated with impaired diurnal BP profiles in hypertensive individuals. EFT (as measured by echocardiography) and NLR appear to be helpful in stratifying cardiometabolic risk.

In this paper, we propose a new control method for manipulator that allows changing motion immediately and flexible even in sudden situations. The reason is that in the future production process, human and robots will collaborate, or the robot will recognize an environment by itself. We defined linear motion and curve motion method of a 3DOF parallel robot. This control method can be controlled in real time. We simulated to verify motion and experimented with parallel robots and laser trackers. Using this control method, the adept motion experiment of the robot was performed, and the cycle time was 0.395 secs. The new control method was applied to the factory of a beverage company.

This study aimed to enable the recognition of the positions and rotation data of objects using the machine vision technology in the packaging process and the pick& place operations by robots using the data. For these objectives, this study proposed the methods of controlling the trigger signals of the camera and minimizing the imaging processing CPU resources in consideration of the recognition range of the campera, size of objects and speed of the conveyor belt. In addition, this study also tried to resolve the problem of an object being recognized as separate objects in the multiple frames of the camera.

Line art colorization is expensive and challenging to automate. A GAN approach is proposed, called Tag2Pix, of line art colorization which takes as input a grayscale line art and color tag information and produces a quality colored image. First, we present the Tag2Pix line art colorization dataset. A generator network is proposed which consists of convolutional layers to transform the input line art, a pre-trained semantic extraction network, and an encoder for input color information. The discriminator is based on an auxiliary classifier GAN to classify the tag information as well as genuineness. In addition, we propose a novel network structure called SECat, which makes the generator properly colorize even small features such as eyes, and also suggest a novel two-step training method where the generator and discriminator first learn the notion of object and shape and then, based on the learned notion, learn colorization, such as where and how to place which color. We present both quantitative and qualitative evaluations which prove the effectiveness of the proposed method., Accepted to ICCV 2019

The present study investigated the immunomodulatory activity and associated mechanisms of heat-treated

Aberrant activation of signal transducer and activator of transcription 3 (STAT3) has been documented in various malignancies including triple-negative breast cancers (TNBCs). The STAT3 transcription factor can regulate the different important hallmarks of tumor cells, and thus, targeting it can be a potential strategy for treating TNBC, for which only limited therapeutic options are available. In this study, we analyzed the possible effect of (-)-galiellalactone and its novel analogues, SG-1709 and SG-1721, and determined whether these agents exerted their antineoplastic effects by suppressing the STAT3 signaling pathway in TNBC cells. The two analogues, SG-1709 and SG-1721, inhibited both constitutive as well as inducible STAT3 phosphorylation at tyrosine 705 more effectively than (-)-galiellalactone, which indicates that the analogues are more potent STAT3 blockers. Moreover, SG-1721 not only inhibited nuclear translocation and DNA binding of STAT3 but also induced apoptosis, and decreased expression of diverse oncogenic proteins. Interestingly, SG-1721 also exhibited an enhanced apoptotic effect when combined with radiotherapy. Furthermore, in vivo administration of SG-1721 significantly attenuated breast xenograft tumor growth via decreasing levels of p-STAT3. Therefore, SG-1721 may be a promising candidate for further application as a pharmacological agent that can target STAT3 protein in treating TNBC.

Background Angina pectoris with a normal coronary angiogram, termed microvascular angina (MVA), is an important clinical entity; however, its causes remain unclear. Autonomic dysfunction is one of the possible causes. Therefore, this study aimed to investigate parasympathetic dysfunction assessed by heart rate recovery (HRR) and increased sympathetic activity assessed by exaggerated blood pressure (BP) response (EBPR) to exercise in MVA. Methods The study participants were consecutive patients with anginal chest pain who underwent both coronary angiography with an ergonovine provocation test and a treadmill exercise test between January 2008 and February 2015. Patients with significant coronary artery disease (coronary artery stenosis ≥50%) or significant coronary artery spasm (≥90%) were excluded. Based on the treadmill exercise test, patients were categorized into the microvascular angina (MVA) group (patients with uniform ST depression ≥1 mm) and the control group. HRR was defined as peak heart rate minus heart rate after a 1 min recovery; blunted HRR was defined as ≤12 beats/min. EBPR was defined as a peak exercise systolic BP ≥210 mmHg in men and ≥ 190 mmHg in women. These parameters were compared between patients with MVA and the controls. Results Among the 970 enrolled patients (mean age 53.1 years; female 59.0%), 191 (20.0%) were diagnosed with MVA. In baseline characteristics, the MVA group had older participants, female predominance, and a higher prevalence of hypertension. The MVA group showed significantly lower HRR 1 min (24.9 ± 15.9 vs. 31.3 ± 22.7, p

Mixed matrix membranes (MMMs) containing zeolitic imidazolite framework-8 (ZIF-8) and UiO-66 as microporous fillers were prepared and evaluated their potential for the separation of a gas mixture produced by a methane reforming process. Hydrothermal synthesis was performed to prepare both the ZIF-8 and UiO-66 crystals, with crystal sizes ranging from 50 to 70 nm for ZIF-8 and from 200 to 300 nm for UiO-66. MMMs were prepared with 15% filler loading for both MMM (ZIF-8) and MMM (UiO-66). MMM (UiO-66) exhibited H2 permeability of 64.4 barrer and H2/CH4 selectivity of 153.3 for single gas permeation, which are more than twice the values that were exhibited by a neat polymer membrane. MMM (ZIF-8) also showed better separation properties than that of a neat polymer membrane with H2 permeability of 27.1 barrer and H2/CH4 selectivity of 123.2. When a gas mixture consisting of 78% Ar/18% H2/4% CH4 flowed into the membranes at 5 bar, the H2 purity increased to as high as 93%. However, no improvement in the mixture gas separation performance was achieved by the MMMs as compared to that of a neat polymer membrane.

Due to an unfortunate oversight this paper was published with typographical errors in Keywords and Eq. (5).

Background and purpose Mutations in the ganglioside-induced differentiation-associated protein 1 gene (GDAP1) are known to cause Charcot-Marie-Tooth disease (CMT). These mutations are very rare in most countries, but not in certain Mediterranean countries. The purpose of this study was to identify the clinical and neuroimaging characteristics of Korean CMT patients with GDAP1 mutations. Methods Gene sequencing was applied to 1,143 families in whom CMT had been diagnosed from 2005 to 2020. PMP22 duplication was found in 344 families, and whole-exome sequencing was performed in 699 patients. Magnetic resonance imaging (MRI) were obtained using either a 1.5-T or 3.0-T MRI system. Results We found ten patients from eight families with GDAP1 mutations: five with autosomal dominant (AD) CMT type 2K (three families with p.R120W and two families with p.Q218E) and three with autosomal recessive (AR) intermediate CMT type A (two families with homozygous p.H256R and one family with p.P111H and p.V219G mutations). The frequency was about 1.0% exclusive of the PMP22 duplication, which is similar to that in other Asian countries. There were clinical differences among AD GDAP1 patients according to mutation sites. Surprisingly, fat infiltrations evident in lower-limb MRI differed between AD and AR patients. The posterior-compartment muscles in the calf were affected early and predominantly in AD patients, whereas AR patients showed fat infiltration predominantly in the anterolateral-compartment muscles. Conclusions This is the first cohort report on Korean patients with GDAP1 mutations. The patients with AD and AR inheritance routes exhibited different clinical and neuroimaging features in the lower extremities. We believe that these results will help to expand the knowledge of the clinical, genetic, and neuroimaging features of CMT.

The present invention discloses a method for synchronizing a clock signal which designs a ring oscillator with a stable fractal structure. The method for synchronizing a clock signal comprises the following steps of: receiving a voltage source from a first chip generating a first clock signal and a second chip generating a second clock signal; oscillating the first clock signal and the second clock signal in a clock line located between the first chip and the second chip; and outputting the first clock signal and the second clock signal as the clock signal having the same frequency and the same phase. The clock line connects three ends of the first chip and the second chip having the same fractal structure.

The blisters formation and destruction induced by the deuterium ions on a polycrystalline tungsten were investigated with varying irradiation deuterium ion fluence from 3.04 × 1023 to 1.84 × 1025 D m−2 s−1 and an fixed irradiated ion energy of 100 eV in an electron cyclotron resonance plasma source, which was similar to the far-scrape off layer region in the nuclear fusion reactors. Target temperature was monitored during the irradiation. Most of blisters formed easily on the grain with (1 1 1) plane orientation which had about 250 nm in diameter. In addition, the areal number density of blisters increased with increasing the ion fluence under the surface temperature reaching to about 900 K. When the fluence exceeded 4.6 × 1024 D m−2, the areal number density of the blister decreased. It could be explained that the destruction of the blister was initiated by erosion at the boundary region where the thickness of blister lid was thin and the sputtering yield was high by oblique incident ions, resulting in remaining the lid open, e.g., un-eroded center dome. It is possible to work as a tungsten dust formation from the plasma facing divertor material at far-SOL region of fusion reactor.

The size of expanded graphite (EG) was controlled using a high-speed crusher because a hybrid of differently sized fillers can induce a synergistic enhancement of the thermal conductivity in polymer composites. We found that the thermal conductivity of a polymer composite filled with both 10 wt% EG and 10 wt% high-speed crusher treated EG (wEG) was synergistically improved by 12.0 and 20.7% compared to that of polymer composites filled with 20 wt% EG and 20 wt% wEG alone, respectively. A three-dimensional (3D) non-destructive analysis using X-ray micro-computed tomography (micro-CT) was applied to explain the synergistic enhancement and to identify the dispersion and 3D network of EG fillers in the composites accurately. According to the non-destructive analysis results, the synergistic enhancement was caused by the formation of efficient thermally conductive pathways due to the hybrid of the differently sized EG and wEG fillers.

This paper presents an advanced estimation method for obtaining the probability density functions of a damage parameter for valve leakage detection in a reciprocating pump. The estimation method is based on a comparison of model data which are simulated by using a mathematical model, and experimental data which are measured on the inside and outside of the reciprocating pump in operation. The mathematical model, which is simplified and extended on the basis of previous models, describes not only the normal state of the pump, but also its abnormal state caused by valve leakage. The pressure in the cylinder is expressed as a function of the crankshaft angle, and an additional volume flow rate due to the valve leakage is quantified by a damage parameter in the mathematical model. The change in the cylinder pressure profiles due to the suction valve leakage is noticeable in the compression and expansion modes of the pump. The damage parameter value over 300 cycles is calculated in two ways, considering advance or delay in the opening and closing angles of the discharge valves. The probability density functions of the damage parameter are compared for diagnosis and prognosis on the basis of the probabilistic features of valve leakage.

We found that the thermal conductivity of polymer composites was synergistically improved by the simultaneous incorporation of graphene nanoplatelet (GNP) and multi-walled carbon nanotube (MWCNT) fillers into the polycarbonate matrix. The bulk thermal conductivity of composites with 20 wt% GNP filler was found to reach a maximum value of 1.13 W/m K and this thermal conductivity was synergistically enhanced to reach a maximum value of 1.39 W/m K as the relative proportion of MWCNT content was increased but the relative proportion of GNP content was decreased. The synergistic effect was theoretically estimated based on a modified micromechanics model where the different shapes of the nanofillers in the composite system could be taken into account. The waviness of the incorporated GNP and MWCNT fillers was found to be one of the most important physical factors determining the thermal conductivity of the composites and must be taken into consideration in theoretical calculations.

Thermal barrier coatings are widely used in aerospace industries to protect exterior surfaces from harsh environments. In this study, functionally graded materials (FGMs) were investigated with the aim to optimize their high temperature resistance and strength characteristics. NiCrAlY bond coats were deposited on Inconel-617 superalloy substrate specimens by the low vacuum plasma spraying technique. Functionally graded Ni-yttria-stabilized zirconia (YSZ) coatings with gradually varying amounts of YSZ (20%-100%) were fabricated from composite powders by vacuum plasma spraying. Heat shield performance tests were conducted using a high- temperature plasma torch. The temperature distributions were measured using thermocouples at the interfaces of the FGM layers during the tests. A model for predicting the temperature at the bond coating–substrate interface was established. The temperature distributions simulated using the finite element method agreed well with the experimental results.

The photomechanical behavior of azobenzene-functionalized liquid-crystalline polymers (azo-LCPs) is closely related to UV light propagation. Here, we report the effect of light absorption by the LC host and the concerted isomerism of azobenzene on this property. In situ measurements of light absorptivity and computer simulations revealed that the light propagation of a liquid-crystalline polymer is affected by the UV absorption of the LC host under the same concerted isomerism of azobenzene. The lower UV light absorption of the LC host results in deeper UV light propagation and a sharper isomerization profile, which eventually induces faster bending when compared to the higher UV light absorption of the LC host. On the other hand, increasing the azobenzene concentration in the polymer greatly decreases the speed of light propagation, which is regarded as one of the factors inhibiting further increases in the bending speed of azo-LCP films.

Enamel microabrasion has become accepted as a conservative, nonrestorative method of removing intrinsic and superficial dysmineralization defects from dental fluorosis, restoring esthetics with minimal loss of enamel. However, it can be difficult to determine if restoration is necessary in dental fluorosis, because the lesion depth is often not easily recognized. This case report presents a method for analysis of enamel hypoplasia that uses quantitative light-induced fluorescence (QLF) followed by a combination of enamel microabrasion with carbamide peroxide home bleaching. We describe the utility of QLF when selecting a conservative treatment plan and confirming treatment efficacy. In this case, the treatment plan was based on QLF analysis, and the selected combination treatment of microabrasion and bleaching had good results.

A tuned mass damper (TMD) is one of the most widely used and accepted systems for the vibration control of building structures subjected to earthquake loads. In large cities, tall buildings are now being constructed closer together. A shared tuned mass damper has been proposed for the vibration control of adjacent buildings. If a shared TMD is designed to effectively reduce the dynamic responses of one building, the control performance for the other building deteriorates. This is because the stiffnesses and damping coefficients of the passive shared TMD connected to each building are fixed. A semi-active shared TMD was proposed in this study to immediately adjust the control force of the shared TMD to each building connected by the shared TMD. The control performance of the semi-active shared TMD was investigated using numerical analyses. For this purpose, two 8-story buildings were used as example structures. Magnetorheological (MR) dampers were used to create the semi-active shared TMD. A multi-input multi-output (MIMO) fuzzy logic controller (FLC) was developed to control the command voltages sent to each MR damper. A multi-objective genetic algorithm was employed to optimize the MIMO FLC. An artificial ground motion was used as an excitation. Based on numerical analyses, it was shown that a semi-active sheared TMD can provide better control performance than that of a conventional TMD, although the semi-active sheared TMD uses only half of the mass used by the conventional TMD system.

Background and study aim: The nonflared ends of fully covered, self-expandable, metal stents (FCSEMSs) may minimize stent-induced ductal injury. Suprapapillary intraductal placement of nonflared FCSEMSs for malignant biliary stricture might reduce duodenobiliary reflux and pancreatitis. The aim of this study was to evaluate the efficacy of a newly modified, nonflared FCSEMS for intraductal placement in patients with malignant biliary stricture. Patients and methods: A total of 51 patients with nonhilar, extrahepatic, malignant biliary stricture were enrolled prospectively. The nonflared FCSEMS is 12 mm in diameter, and has a central saddle and a distal lasso of 7 cm in length. An FCSEMS was placed above the papilla in all patients, with the central saddle positioned at the stricture to prevent stent migration. Results: The technical and clinical success rates were 100 % and 98 %, respectively. Early adverse events occurred in one patient (2.0 %; mild pancreatitis). A total of 12 patients underwent surgery with curative intent, one of whom (8.3 %) experienced a postoperative adverse event. No stent migration occurred in any of the patients. Cholecystitis developed in one patient (2.0 %) as a late adverse event. Stent occlusion occurred in 44.7 % (17/38), and endoscopic removal of the stent was successful in 87.5 % of patients. The mean stent patency was 297 days (95 % confidence interval, 211 – 383). Conclusions: Intraductal placement of the nonflared FCSEMS, 12 mm in diameter, was feasible for the palliative and preoperative management of patients with malignant biliary stricture. Long-term follow-up and prospective comparative studies are needed to evaluate the usefulness of intraductal placement of this stent.