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In this article, a simple way to determine algorithmic parameters included in time approximations of two-stage implicit time schemes is presented. To be specific, algorithmic parameters of time approximations are mathematically determined to give higher-order total energy convergence rates for conservative nonlinear problems while satisfying traditional linear accuracy requirements. Due to the use of newly proposed algorithmic parameters, two-stage implicit time schemes can possess enhanced total energy conserving capabilities for conservative nonlinear problems while providing improved linear performances when compared with those of the existing two-stage time schemes. Enhanced total energy conserving capabilities achieved through the use of newly proposed algorithmic parameters do not require any additional computational efforts when compared with the existing two-stage schemes. This article also explains that a certain standard type of two-stage implicit time schemes can reduce computational time and effort in linear analyses if effective coefficient matrices of the first and second stages are constructed identically. For the verification of improved numerical performances, linear and nonlinear benchmark problems are solved, and their numerical results are investigated to support the main discussions of this article.

We configured a long-distance ranging apparatus to test the principle of dual-comb time-of-flight measurement using ultrashort lasers. Emphasis was given to the evaluation of open-air performance quantitatively in terms of the measurement resolution and stability. The test results revealed that our dual-comb asynchronous optical pulse sampling permits micrometer-resolved ranging with a repeatability of 2.05 μm over a 648 m distance in dry weather conditions. Further atmospheric effects were evaluated in three different weather conditions with corresponding Allan deviations. Finally, the capability of simultaneous determination of multiple targets was verified with the potential of advanced industrial applications, such as manufacturing, surveying, metrology, and geodesy.

Multilateration tracking systems (MLTSs) are used in industrial three-dimensional (3D) coordinate measuring applications. For high-precision measurement, system parameters must be calibrated properly in advance. For an MLTS using absolute distance measurement (ADM), the conventional self-calibration method significantly reduces estimation efficiency because all system parameters are estimated simultaneously using a complicated residual function. This paper presents a novel self-calibration method that optimizes ADM to reduce the number of system parameters via highly precise and separate estimations of dead paths. Therefore, the residual function to estimate the tracking station locations can be simplified. By applying a suitable mathematical procedure and solving the initial guess problem without the aid of an external device, estimation accuracy of the system parameters is significantly improved. In three self-calibration experiments, with ADM repeatability of approximately 3.4 µm, the maximum deviation of the system parameters estimated by the proposed self-calibration method was 68.6 µm, while the maximum deviation estimated by the conventional self-calibration method was 711.9 µm. Validation of 3D coordinate measurements in a 1000 mm × 1000 mm × 1000 mm volume showed good agreement between the proposed ADM-based MLTS and a commercial laser tracker, where the maximum difference based on the standard deviation was 17.7 µm. Conversely, the maximum difference was 98.8 µm using the conventional self-calibration method. These results confirmed the efficiency and feasibility of the proposed self-calibration method.

We report an absolute interferometer configured with a 1 GHz microwave source photonically synthesized from a fiber mode-locked laser of a 100 MHz pulse repetition rate. Special attention is paid to the identification of the repeatable systematic error with its subsequent suppression by means of passive compensation as well as active correction. Experimental results show that passive compensation permits the measurement error to be less than 7.8 μm (1 σ) over a 2 m range, which further reduces to 3.5 μm (1 σ) by active correction as it is limited ultimately by the phase-resolving power of the phasemeter employed in this study. With precise absolute distance ranging capability, the proposed scheme of the photonic microwave interferometer is expected to replace conventional incremental-type interferometers in diverse long-distance measurement applications, particularly for large machine axis control, precision geodetic surveying and inter-satellite ranging in space.

This study fabricated a low-cost activated carbon (AC) adsorbent from readily available bamboo trees to control indoor CO2 levels and reduce energy costs associated with sustaining clean indoor air. Bamboo is naturally high in potassium content and has narrow fibrous channels that could enhance selective CO2 adsorption. The prepared bamboo-based activated carbon (BAC) exhibits predominantly micropores with an average pore size of 0.17 nm and a specific surface area of 984 m2/g. Upon amination, amine functionalities, such as pyridine, pyrrole, and quaternary N, were formed on its surface, enhancing its CO2 adsorption capacity of 0.98 and 1.80 mmol/g for low-level (3000 ppm) and pure CO2 flows at the ambient condition, respectively. In addition, the 0.3% CO2/N2 selectivity (αs,g) of the prepared sorbents revealed a superior affinity of CO2 by BAC (8.60) over coconut shell-based adsorbents (1.16–1.38). Furthermore, amination enhanced BAC’s CO2αs,g to 13.4. These results exhibit this sustainable approach’s potential capabilities to ensure the control of indoor CO2 levels, thereby reducing the cost associated with mechanical ventilation systems. Further research should test the new sorbent’s adsorption properties (isotherm, kinetics, and thermodynamics) for real-life applicability.

This study fabricated a low-cost activated carbon (AC) adsorbent from readily available bamboo trees to control indoor CO[sub.2] levels and reduce energy costs associated with sustaining clean indoor air. Bamboo is naturally high in potassium content and has narrow fibrous channels that could enhance selective CO[sub.2] adsorption. The prepared bamboo-based activated carbon (BAC) exhibits predominantly micropores with an average pore size of 0.17 nm and a specific surface area of 984 m[sup.2]/g. Upon amination, amine functionalities, such as pyridine, pyrrole, and quaternary N, were formed on its surface, enhancing its CO[sub.2] adsorption capacity of 0.98 and 1.80 mmol/g for low-level (3000 ppm) and pure CO[sub.2] flows at the ambient condition, respectively. In addition, the 0.3% CO[sub.2]/N[sub.2] selectivity (α[sub.s,g]) of the prepared sorbents revealed a superior affinity of CO[sub.2] by BAC (8.60) over coconut shell-based adsorbents (1.16–1.38). Furthermore, amination enhanced BAC’s CO[sub.2]α[sub.s,g] to 13.4. These results exhibit this sustainable approach’s potential capabilities to ensure the control of indoor CO[sub.2] levels, thereby reducing the cost associated with mechanical ventilation systems. Further research should test the new sorbent’s adsorption properties (isotherm, kinetics, and thermodynamics) for real-life applicability.

The application of laser treatments beginning on the day of stitch removal has been demonstrated to improve scar quality. However, there are few guidelines for the treatment of immature scars (ISs), which are defined as “scars whose features are not yet expressed.” The purpose of this study was to extract information about early combination laser treatment (CLT) beyond what is currently known by analyzing 33 pairs of pre-treatment and post-treatment photographs of ISs. Two hundred fifty medical records of patients with scars were reviewed, and 33 scars were included in the study. The included scars were treated with vascular lasers (585 or 532 nm) followed by 1550-nm fractional lasers from May 2014 to July 2015 (fewer than 52 days after stitch removal, Fitzpatrick’s skin types III–IV, mean age = 16.0 years). Blinded evaluators (one plastic surgeon and two dermatologists) evaluated the pre-treatment and post-treatment photographs. The pre-treatment photographs were scored on a spectrum from “0,” when no difference with the surrounding unaffected skin was observed, to “100,” when the worst scarring was present. The pre-treatment and post-treatment photographs were compared, and the results were graded on a spectrum from 0, when no difference between the pre-treatment and post-treatment photographs was observed, to 100, when no difference was observed between the post-treatment skin and the surrounding unaffected skin. Statistical analyses were performed with PASW 17.0, SPSS Korea, Seoul, Korea ( p  < 0.05). The improvement scores (ImS) and weighted scores (Wtd: i.e., weighted according to the pre-treatment scores) were used as dependent variables. The average improvement score was 87.98 (median = 90). Seventeen cases were scored as 100-point improvements. The facial and non-facial scars exhibited differences in the ImS and Wtd scores. The Wtd scores were negatively correlated with the temporal gap (in days) between stitch removal and the beginning of CLT. No significant difference in the Wtd scores was demonstrated between the two vascular laser groups. Patient age and Wtd score were negatively correlated, and a significant difference was observed in the Wtd scores between the age groups (≥15 and <15 years old). CLT for ISs results in excellent outcomes. Better results are achieved with earlier CLT initiation following stitch removal. Better outcomes can be expected for younger patients and for facial scars. We found that 532 and 585-nm lasers are equally effective for CLT of ISs.

The objectives of this study were to prepare a high-purity hydroxylammonium nitrate (HAN) solution and evaluate the performance of various types of metal oxide/honeycomb catalysts during the catalytic decomposition of the HAN solution. Hydroxylammonium nitrate was prepared via a neutralization reaction of hydroxylamine and nitric acid. FT-IR was used to analyze the chemical composition, chemical structure, and functional groups of the HAN. The aqueous HAN solution obtained from pH 7.06 showed the highest concentration of HAN of 60% and a density of 1.39 g/mL. The concentration of HAN solution that could be obtained when the solvent was evaporated to the maximum level could not exceed 80%. In this study, catalysts were prepared using a honeycomb structure made of cordierite (5SiO2-2MgO-2Al2O3) as a support, with Mn, Co, Cu, Pt, or Ir impregnated as active metals. The pore structure of the metal oxide/honeycomb catalysts did not significantly depend on the type of metal loaded. The Cu/honeycomb catalyst showed the strongest effect of lowering the decomposition onset temperature in the decomposition of the HAN solution likely due to the intrinsic activity of the Cu metal being superior to that of the other metals. It was confirmed that the effect of the catalyst on the decomposition mechanism of the aqueous HAN solution was negligible. Through a repetitive cycle of HAN decomposition, it was confirmed that the Cu/honeycomb catalyst could be recovered and reused as a catalyst for the decomposition of an aqueous HAN solution.

Objective In the esthetic field, the masseter muscle is commonly targeted by botulinum neurotoxin for facial contouring. However, multiple botulinum neurotoxin injections have been reported to cause muscle fibrosis. Ultrasonography can be useful for clinical consideration in such cases. Materials and Methods This study presents nine cases of masseteric fibrosis caused by repeated botulinum neurotoxin injections with ultrasonographic analysis of full and partial masseteric fibrosis. Results Repetitive botulinum neurotoxin injections resulted in reduced masseter muscle volume, which frequently appeared hyperechoic on ultrasonography. The hyperechoic region was mostly located in the deep and posterior portions; however, in some cases, it was observed throughout the muscle, including the superficial, deep, or both areas. Conclusion The fibrotic masseter muscles appear hyperechoic, and ultrasonography is necessary to analyze the degree and location of fibrosis. Predictions can be made for cases in which botulinum neurotoxin injections may have less of an effect after ultrasonography. Because muscle fibrosis can be localized, it is necessary to confirm the degree and location of fibrosis before determining the effective area of injection. In clinical practice, muscle fibrosis may be visible in a specific area where blind injections are administered.

It would be hard to verify and quantify any cumulative impacts caused by a complex change order at the construction field. In particular, it is said that, parties to a contract in the domestic construction field fail to really understand even a concept when it comes to disruption cost and lost labor productivity expenses researched in this paper. Thus, this aims to present how to determine costs of loss due to disruption among the accumulated effects. To do so, we have reviewed national contract laws and relative legislations relating to disruption and lost labor productivity. Furthermore, it also tries to suggest available estimation methods in the country using cases in which disruption due to a delay in material supply.