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The general bone anabolic effect of photobiomodulation (PBM) is largely accepted. As a result, PBM therapy is expected to be beneficial in the medical fields of dentistry and bone healing. However, most of the previous in vitro studies on PBM and bone metabolism were performed with single-cell cultures of osteoclast-lineage cells or osteoblast-lineage cells. In the present study, the bone-modulating effects of PBM were evaluated in an in vitro osteoblast/osteoclast co-culture system. Mouse bone marrow-derived macrophages (BMMs) and mouse calvarial pre-osteoblasts cells were purified and used as precursor cells for osteoclasts and osteoblasts, respectively. The PBM effects on single-cell culture of osteoclasts or osteoblasts as well as co-culture were examined by 1.2 J/cm2 low-level Ga-Al-As laser (λ = 808 ± 3 nm, 80 mW, and 80 mA; spot size, 1cm2; NDLux, Seoul, Korea) irradiation for 30 s at daily intervals throughout culture period. At the end of culture, the osteoclast differentiation and osteoblast differentiation were assessed by TRAP staining and ALP staining, respectively. The expressions of osteoclastogenic cytokines were evaluated by RT-PCR and Western blot analyses. Under the single-cell culture condition, PBM enhanced osteoblast differentiation but had minor effects on osteoclast differentiation. However, in the co-culture condition, its osteoblastogenic effect was maintained, and osteoclast differentiation was substantially reduced. Subsequent RT-PCR analyses and western blot results revealed marked reduction in receptor activator of NF-κB ligand (RANKL) expression and elevation in osteoprotegerin (OPG) expression by PBM in co-cultured cells. More importantly, these alterations in RANKL/OPG levels were not observed under the single-cell culture conditions. Our results highlight the different effects of PBM on bone cells based on culture conditions. Further, our findings suggest the indirect anti-osteoclastogenic effect of PBM, which is accompanied by a decrease in RANKL expression and an increase in OPG expression. [ABSTRACT FROM AUTHOR]

This study aimed to an experiment to analyze the spatial levee breach mechanisms due to overtopping according to the degree of compaction. A levee experiment was performed using four different degree of compaction implemented by adjusting the levee compaction thickness and number of compactions, and the effects of the degree of compaction on levee breaching were observed. Under the low degree of compaction, the scale of the levee breach over time was relatively large, and the breach discharge was also significant. This study also observed the change in velocity of the levee crest area through Large Scale Particle Image Velocimetry (LSPIV) analysis of the velocity field at each levee breach stage; in particular, the location where the maximum velocity occurred in the crest area differed according to the degree of compaction. The relationship between the degree of compaction and peak breach discharge shown in experimental results suggests the degree of compaction can directly affect the breach of the levee and the flooding velocity at the low-land area. The clear correlations between the degree of compaction and breach discharge and breach size over time presented in this study can provide detailed information for the design standards and maintenance of the levee. [ABSTRACT FROM AUTHOR]

In this study, using the modified Einstein procedure, data on sediment load were systematically collected and analyzed by year, period, watershed, and main stream and tributaries in South Korean rivers. It was found that the sediment load and concentration differ significantly depending on the region, even in the same area and at the same time, especially in areas with a large minimum-maximum discharge ratio. Therefore, the application of the relationship between discharge and sediment load across all time and space needs to be precise, and data have to be selected separately according to the relational application conditions. In addition, existing sediment transport formulas were compared by applying various goodness-of-fit methods that were well suited to the measured dataset. The results showed that the optimal sediment transport formula varied according to the goodness-of-fit method. Furthermore, while the Ackers and White approach was found to be generally suitable; however, the correlation figures alone were not conclusive. Therefore, a quantitative determination must be made as to how the application of simple fitness methods affects the selection of optimal sediment transport formulas. [ABSTRACT FROM AUTHOR]

As part of efforts to fabricate FeMnAlC lightweight steels suitable for high-temperature applications, the influence of Nb addition on the microstructure and tensile deformation behaviors has been investigated. Electron backscattered diffraction analysis showed that Fe–20Mn–8Al–1.0C base steel consisted of a full austenite matrix after solution treatment, and the addition of 0.1 wt pct Nb resulted in grain refinement from 56 to 23 μm without significant changes in the microstructure. After aging treatment at 550 °C for 1 hour, significant hardening occurred (base steel: 257 → 392 HV, Nb-added steel: 273 → 359 HV) by the precipitation of nanosized κ-carbides with sizes of 2 to 6 nm. A higher strain-hardening rate at 400 °C by Nb addition was clearly brought about by the mutual interaction of dislocations with κ-carbides (through both shearing and Orowan bypassing mechanisms). The nanoindentation results and the calculation of the strength increment indicated that Nb addition led to a smaller hardening by κ-carbide precipitation. In terms of the microstructural evolution by thermal exposure time (100 to 5000 hours at 400 °C), it was first found that the intensive slip band impingement at grain boundaries occurred in these lightweight steels, but Nb addition effectively inhibited the significant reduction in ductility by suppressing the formation of slip bands. The effect of Nb addition is discussed in terms of the collaborative effects of grain refinement, κ-carbide precipitation, and microstructural stability. [ABSTRACT FROM AUTHOR]

Using probability operators and Fourier transforms of CP-instruments on von Neumann algebras, we give necessary and sufficient conditions for operators to be probability operators associated with covariant CP-instruments or to be Fourier transforms of covariant CP-instruments. We discuss a convolution semigroup of covariant CP-instruments and a semigroup of probability operators associated with CP-instruments on von Neumann algebras. [ABSTRACT FROM AUTHOR]

In this paper, by applying the intertwining properties, we introduce the fractional powers of the number operator perturbed by generalized Gross Laplacians (infinite dimensional Laplacians), which are special types of the infinitesimal generators of generalized Mehler semigroups. By applying the intertwining properties and semigroup approach, we study the Langevin type equations associated with the infinite dimensional Laplacians and with white noise distributions as forcing terms. Then we investigate the unique solution of the fractional Langevin type equations associated with the Riemann-Liouville and Caputo time fractional derivatives, and the fractional power of the infinite dimensional Laplacians, for which we apply the intertwining properties again. For our purpose, we discuss the fractional integrals and fractional derivatives of white noise distribution valued functions. [ABSTRACT FROM AUTHOR]

Damper is frequently used to suppress panel vibration and related vehicle interior noise. Unlike an unconstrained damper, a method to find material properties of a constrained damper is more complicated. This study presents a verified method for obtaining material properties of a constrained asymmetrical damper. The most important material parameters of this constrained damper are shear modulus, shear factor, and of course damping loss factor. The paper provides newly corrected equations to give proper numerical values of these parameters. The difference of natural frequencies between the test and the simulation using the estimated values is about 2 %, which shows that the estimation method is correctly presented. Important characteristics such as shear motion and wavelength of a composite beam constrained by a damper are also investigated. Finally, vibration response of a vehicle roof with a constrained damper is measured and is compared to the simulation. It is noticed that the correlation is much improved, comparing with the simulation based on old material properties. [ABSTRACT FROM AUTHOR]

In this paper, we prove a Krein space J-representation theorem for local α -completely positive maps on locally C ∗ -algebras. Using this representation, we construct a Krein space J-representation associated with a pair of two maps (φ , Φ) where φ is a local α -completely positive map on a locally C ∗ -algebra and Φ is a φ -map. Also, we discuss the minimality of Krein space J-representations, and as an application, we establish the Radon–Nikodým theorem for local α -completely positive maps. [ABSTRACT FROM AUTHOR]

There is a great demand for a dispersion evaluation method that can be applied even when a nano-sized filler is incorporated, that can evaluate a three-dimensional (3D) quantitative dispersion of a composite material, and that is not expensive and time consuming. Here, we proposed light-intensity dispersion index (LDI) to quantitatively evaluate the dispersion based on the light scattering distribution on divided optical microscopy (OM) images. Difference in the light-intensity is determined by the dispersion and agglomeration of the filler in the polymer matrix; therefore, the smaller the distribution and the number of peaks of light-intensity, the more uniform the dispersion. The reliability of the developed LDI was improved by introducing an agglomeration size weighting factor. Furthermore, the validity of the LDI was also verified in comparison with the experimental results. In conclusion, we have successfully developed a method for the 3D quantitative dispersion evaluation of nanocomposites with minimal cost and time consumption. [ABSTRACT FROM AUTHOR]

Habitat suitability index (HSI) is a fundamental factor in ecological river-restoration projects for assessing fish habitat to create inhabited environment for aquatic organisms. An accurate estimation of HSI requires long-term-monitored data including flow velocity, water depth, and bed materials; however, this is not easy to collect, and the dataset comprises local characteristics. Therefore, it is difficult to present a generalized method of HSI estimation with limited local and temporal data. In this study, the probability distribution was applied for HSI estimation with limited data measured in the tributaries of Han and Geum Rivers in South Korea. Log-normal distributions were applied to the water depth and velocity data of aquatic habitat for Zacco platypus, and then the developed log-normal distributions were used as the HSI. The HSIs developed by applying the log-normal distribution were compared with the HSIs developed using the instream flow and aquatic system group (IFASG) method. By using the log-normal-distribution-based HSIs, the environmental flows estimated through the physical-habitat-assessment models based on instream flow incremental methodology were also compared with the IFASG-based results. The environmental flows were determined to be similar within an optimal range in both cases of the tributaries of Han and Geum Rivers. [ABSTRACT FROM AUTHOR]

The uncertainty of flow measurements obtained by the float method is evaluated following the international organization for standardization (ISO) 748 guideline. However, the standard uncertainty of an average flow rate has not been considered and the quantitative uncertainty has never been computed for flow measurements made using the float method. Therefore, in this study, a stream-scale experiment was performed to estimate the standard uncertainty of the mean flow velocity by considering the flow velocity uncertainty of floats. The results demonstrated that the standard uncertainty of the mean flow velocity measured by a surface float was 15.30%, while that measured by a rod float having a 50-cm draft was 11.05%. Through these results, the measurement uncertainty of discharge was evaluated according to the GUM (guide for the expression of uncertainty in measurement) method. The measurement uncertainty was then evaluated considering the standard uncertainty of the mean flow velocity. The measurement uncertainty of the discharge was increased by 3.4% as compared with that calculated without considering the standard uncertainty. [ABSTRACT FROM AUTHOR]

Numerical simulations for bed change and bank erosion were performed using a two-dimensional numerical model to analyze the effect of channel width variation on bed change for the 4.2 km section upstream of Changnyeong-Haman Weir in the Nakdong River of South Korea. Simulation result of bed degradation without bank erosion for 120 days with 1,000 m3/s of flow discharge was about 2 m greater than the case of simulation with bank erosion. The narrow channel section was continuously degraded over time in the simulation with the fixed boundary for bank lines. However, bed degradation decreased as the channel width increased when bank erosion or artificial width extension were considered in the modeling. The equilibrium condition for topographical changes in the study reach was demonstrated by the modeling results with different channel width and simulation time. [ABSTRACT FROM AUTHOR]

We derive the Wick calculus for test and generalized functionals of noncommutative white noise corresponding to q-deformed commutation relations with q∈(-1,1). We construct a Gel’fand triple centered at the q-deformed Fock space in which both the test, nuclear space and its dual space are algebras with respect to the addition and the Wick multiplication. Furthermore, we prove a Våge-type inequality for the Wick product on the dual space. [ABSTRACT FROM AUTHOR]

We establish a noncommutative extension of the Fuk-Nagaev inequalities for random variables in a noncommutative probability space. As applications, we first obtain noncommutative versions of Bennett inequality and Rosenthal inequality, and secondly, we study the weak law of large numbers for weighted sums in a noncommutative probability space and the weak law of large numbers for weighted sums of probability measures corresponding to the free additive convolutions. [ABSTRACT FROM AUTHOR]

We establish the asymptotic regularity and the Δ-convergence of the sequence constructed by alternating projections onto closed convex sets in a CAT(κ) space with κ>0. Furthermore, the strong convergence of the alternating von Neumann sequence is presented under certain regularity or compactness conditons. [ABSTRACT FROM AUTHOR]

A program for stable channel design was developed to perform the sensitivity analysis for stable conditions with various sediment transport equations. It provides a useful solution considering design constraints such as a fixed width and depth as well as various solutions for stable channel condition with a wide range. This program applied to the section of the abandoned channel restoration in the Cheongmi Stream, a tributary of Han River in Korea. The predicted slopes with sediment transport equations were steeper than the current channel slope. Overall, the current section has deeper depth and milder bed slope compared to the stable channel prediction results. This could be represented in relation to the formation of sandbars around the study reach in the Cheongmi Stream. Regarding the application to the Cheongmi Stream with the fixed base width, Yang's equation produced the steepest slope and the shallowest depth. In the case of the application with the fixed depth, the base width predicted by Yang's equation was the narrowest. For all sediment transport equations, the predicted base width was narrower than the current section. [ABSTRACT FROM AUTHOR]

In this paper, we investigate $$\Phi $$ -maps associated to a certain type of $$\alpha $$ -completely positive maps. We then prove a Kasparov-Stinespring-Gel'fand-Naimark-Segal (KSGNS) type theorem for $$\alpha $$ -completely positive maps on Krein $$C^*$$ -modules and show that the minimal KSGNS construction is unique up to unitary equivalence. We also establish a covariant version of the KSGNS type theorem for a covariant $$\alpha $$ -completely positive map and study the structure of minimal covariant KSGNS constructions. [ABSTRACT FROM AUTHOR]

We first study a general type of convolutions, parameterized by operators, on white noise functionals and study a relation between the convolution and the generalized Fourier-Mehler transform. Secondly, we extend the convolution of generalized white noise functionals to a convolution of white noise operators. Then, as factorization properties of the convolutions, we study a relation between the convolution and quantum generalized Fourier-Mehler transform. [ABSTRACT FROM AUTHOR]

The upstream channel of the Nakdong River Estuary Barrage (NREB) has experienced sedimentation problems requiring annual dredging operation after the construction. The main purpose of sediment dredging is to prevent flooding during late summer. Numerical simulation and volume analysis using field surveying data for the Lower Nakdong River have been conducted to quantify the bed changes with and without dredging operation and to analyze the effectiveness of dredging at the NREB. As a result, it is presented that the bed change rate (sedimentation rate) after dredging is much faster than the bed condition without dredging. The water surface rising of the maximum 10 cm was generated in case the dredging was not considered in the modeling. Volumetric analysis of bed changes using field surveying data presented that 41 percent of total sediment erosion was eliminated by natural flushing and 59 percent was dredged in the field. Because it is noticeable that dredged section is redeposited rapidly after dredging during low flow through the 2D simulation, it is expected that most of total sediment erosion (at least more than 41% of total sediment erosion) is caused by natural flushing due to the floods. Therefore, it is highly recommended to use natural flushing or intentional sluicing techniques for sedimentation control methods at the NREB. [ABSTRACT FROM AUTHOR]

This study was carried out to optimize dyeing conditions of unripe Citrus Unshiu extract on silk fabric and to evaluate antimicrobial activity of the dyed fabric for its potential use as a functional natural dye. Unripe fruits of Citrus Unshiu in Jeju Island, Korea, extracted in 80 % Ethanol solution to final solid dye powder were dyed on silk fabric under a variety of conditions such as dye bath concentrations, temperature, and dyeing duration together with mordanting. Dyeing fastness properties to washing, rubbing, perspiration, and light were tested and the antimicrobial activities of the dyed fabric against Staphylococcus aureus and Klebsiella pneumoniae were investigated quantitatively. As results, the fabric showed the maximum dye uptake ( K/S) under the conditions of 80 °C for temperature, 30 min for duration, and 600 % (o.w.f.) for dye concentration. Both pre- and post-mordanting seemed not to be effective on increasing K/S values of the dyed silk fabrics under the optimum dyeing conditions. Fastness ratings to washing, rubbing, and perspiration were all very good (4-5 grades) for both 300 and 600 % dyed silk fabrics. Excellent antimicrobial activities over 99 % reduction rate against two both bacteria were exhibited for all of dyed fabrics undergone more than 300 % of dye concentration. From these results, it was concluded that the dye concentration of 300 % of unripe Citrus Unshiu could be employed to produce antimicrobial silk fabric. Furthermore, to get more saturated shades on the fabric by the citrus, higher dye concentration such as 600 % was available as well. [ABSTRACT FROM AUTHOR]

Multi-layered TiO2 nanostructured films were fabricated to improve the light harvest efficiency of the dye-adsorbed TiO2 electrode in dye-sensitized solar cells (DSSCs) by light scattering. Three different structures of TiO2 electrodes, with layers consisting of TiO2 pastes with average diameters of 9, 20, and 300 nm, respectively, were fabricated and their photovoltaic effects on the DSSC devices were investigated. By utilizing the multi-layered TiO2 electrode constructed using the three different TiO2 pastes, the overall power conversion efficiency of the DSSC devices in the PEG-based electrolyte was increased to 5.24% under irradiation of 100 mW/cm2 at AM 1.5. [ABSTRACT FROM AUTHOR]

High regularity is important in manufacturing spun yarn. Among controllers used in regularity control, existing PID controller is suitable for linear time-invariant systems but not for the control of sliver draft systems with non-linear characteristic. Thus, the present study designed a knowledge-based fuzzy controller in consideration of disturbance and non-linear characteristic of sliver draft systems. RLS (Recursive Least Squares) was used as an estimation algorithm to formulate a model used in computer simulation for implementing the controller, and real time estimation was made using real data from draft systems to get a model close to actual systems. This research used a estimation model in designing a knowledge-based controller that minimizes the variation of control response to the sliver linear density of the system, and the result of linear density control was used to prove the superiority of the controller in control performance through CV%. [ABSTRACT FROM AUTHOR]

In this paper we shall show the heredity of a differentiable one-parameter semigroup under the second quantization and then discuss the resolvent of the differential second quantization operator and the potentials of test white noise functionals. As an application, we shall investigate the existence of solutions of the Poisson-type equations associated with differential second quantization operators as well as operators similar to differential second quantization operators. [ABSTRACT FROM AUTHOR]

The paper studies the estimation and the portmanteau test for double AR(p) model with Laplace(a,b) distribution. The double AR(p) model is investigated to propose firstly the quasi-maximum exponential likelihood estimator, design a portmanteau test of double AR(p) on the basis of autocorrelation function, and then establish some asymptotic results. Finally, an empirical study shows that the estimation and the portmanteau test obtained in this paper are very feasible and more effective. [ABSTRACT FROM AUTHOR]