• Journal of the Korean Society of Physical Medicine
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• v.17 no.4
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• pp.141-150
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• 2022

PURPOSE: This study was conducted to investigate the effects of non-elastic and elastic tapes on pain, craniovertebral angle, and balance in forward head posture (FHP) patients. METHODS: A total of 44 adults with FHP were randomly assigned to a group that performed a stretching exercise after non-elastic taping (n = 22) and another group that performed the stretching exercise after elastic taping (n = 22), respectively. The stretching exercise was performed five times a week for 30 minutes per session. The visual analogue scale was used to compare neck pain, the craniovertebral angle was measured to compare alignment, and the limit of stability was measured to compare balance. RESULTS: The groups that performed the stretching exercise after both elastic and non-elastic taping showed significant positive changes in pain and the craniovertebral angle of the head in pre- post measurements (p < .05). In the follow-up test for the pain and craniovertebral angle, there was no significant difference from the post-test in the non-elastic group (p > .05), but a significant difference was seen in the elastic group (p < .05). CONCLUSION: Stretching exercises with taping for patients with a FHP are more effective in improving pain and alignment. However, the short-duration tape application did not affect the balancing ability. When the non-elastic tape was used, the effect lasted longer than that of the elastic tape, and pain relief was effective in the case of the elastic tape. Therefore, tape therapy would be more effective if customized according to the patient's condition.

• Journal of Electrochemical Science and Technology
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• v.13 no.4
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• pp.431-437
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• 2022

As one of the most hazardous and deadliest pathogens, Listeria monocytogenes (LM) posed various serious diseases to the human being, thus designing effective strategy for its detection is of great significance. In this work, by preparing Ti₃C₂T_x MXenes nanoribbon (Ti₃C₂T_xR) as carrier and selecting thionine (Th) acted simultaneously as signal probe and functional monomer, a LM pathogen-imprinted polymers (PIP) integrated probe electrochemical sensor was design to monitor LM for the first time, that was carried out through the electropolymerization of Th on the Ti₃C₂T_xR/GCE surface in the existence of LM. Upon eluting the templates from the LM imprinted cavities, the fabricated PIP/Ti₃C₂T_xR/GCE sensor can rebound LM cells effectively. By recording the peak current of Th as the response signal, it can be weakened when LM cell was re-bound to the LM imprinted cavity on PIP/Ti₃C₂T_xR/GCE, and the absolute values of peak current change increase with the increasement of LM concentrations. After optimizing three key parameters, a considerable low analytical limit (2 CFU mL^-1) and wide linearity (10-10⁸ CFU mL^-1) for LM were achieved. In addition, the experiments demonstrated that the PIP/Ti₃C₂T_xR sensor offers satisfactory selectivity, reproducibility and stability.

• Analytical Science and Technology
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• v.36 no.4
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• pp.180-190
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• 2023

The presence of process related impurities in any drug or the drug product was associated with its safety, stability and efficacy. The overall literature survey proved that there is no method published on the assessment of process related impurities in brigatinib. In this study, a simple, reliable and stable HPLC qualitative method was reported for quantification of process related impurities with easy and quick extraction procedure. The impurities along with standard brigatinib was resolved on Lichrospher^® C18 (250 mm × 4.6 mm; 5 ㎛ particle size) column in room temperature using methanol, acetonitrile, pH 4.5 phosphate buffer in 55:25:20 (v/v) at 1.0 mL/min as mobile phase and UV detection at 261 nm. The method produces well resolved peaks at retention time of 4.60 min, 12.28 min, 3.37 min, 7.34 min and 8.39 min respectively for brigatinib, impurity A, B, C and D. The method produces a very sensitive detection limit of 0.0065 ㎍/mL, 0.0068 ㎍/mL, 0.0053 ㎍/mL and 0.0058 ㎍/mL for impurity A, B, C and D respectively with calibration curve linear in the concentration range of 22.5-135 ㎍/mL for brigatinib and 0.0225-0.135 ㎍/mL for impurities. The method produces all the validation parameters under the acceptable level and doesn't produces any considerable changes in peak area response while minor changes in the developed method conditions. The method can effectively resolve the unknown stress degradation products along with known impurities with less % degradation. The method can efficiently resolve and quantify the impurities in formulation and hence can suitable for the routine quality analysis of brigatinib in raw material and formulation.

• Korean Journal of Materials Research
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• v.32 no.12
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• pp.538-544
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• 2022

In existing ceramic mold manufacturing processes, inorganic binder systems (Si-Na, two-component system) are applied to ensure the effective firing strength of the ceramic mold and core. These inorganic binder systems makes it possible to manufacture a ceramic mold and core with high dimensional stability and effective strength. However, as in general sand casting processes, when molten metal is injected at room temperature, there is a limit to the production of thin or complex castings due to reduced fluidity caused by the rapid cooling of the molten metal. In addition, because sodium silicate generated through the vitrification reaction of the inorganic binder is converted into a liquid phase at a temperature of 1,000 ℃. or higher, it is somewhat difficult to manufacture parts through high-temperature casting. Therefore, in this study, a high-strength ceramic mold and core test piece with effective strength at high temperature was produced by applying a Si-Na-Ti three-component inorganic binder. The starting particles were coated with binary and ternary inorganic binders and mixed with an organic binder to prepare a molded body, and then heat-treated at 1,000/1,350/1,500 ℃ to prepare a fired body. In the sample where the two-component inorganic binder was applied, the glass was liquefied at a temperature of 1,000 ℃ or higher, and the strength decreased. However, the firing strength of the ceramic mold sample containing the three-component inorganic binder was improved, and it was confirmed that it was possible to manufacture a ceramic mold and core via high temperature casting.

• Korean Journal of Materials Research
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• v.32 no.12
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• pp.545-552
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• 2022

Tin-antimony sulfide nanocomposites were prepared via hydrothermal synthesis and a N₂ reduction process for use as a negative electrode in a sodium ion battery. The electrochemical energy storage performance of the battery was analyzed according to the tin-antimony composition. The optimized sulfides exhibited superior charge/discharge capacity (770 mAh g^-1 at a current density of 100 mA g^-1) and stable lifespan characteristics (71.2 % after 200 cycles at a current density of 500 mA g^-1). It exhibited a reversible characteristic, continuously participating in the charge-discharge process. The improved electrochemical energy storage performance and cycle stability was attributed to the small particle size, by controlling the composition of the tin-antimony sulfide. By optimizing the tin-antimony ratio during the synthesis process, it did not deviate from the solubility limit. Graphene oxide also acts to suppress volume expansion during reversible electrochemical reaction. Based on these results, tin-antimony sulfide is considered a promising anode material for a sodium ion battery used as a medium-to-large energy storage source.

• Journal of the Korea Society of Computer and Information
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• v.14 no.3
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• pp.13-26
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• 2009

In this raper, We propose the alternative solution, RTOS-based system to replace the PLC 4hat has used the automation system for industrial processes. RTOS-based system is constructed the PC and RTOS as hardware and software. It overcomes the limit of PLC and guarantees the stability and reliability. Also, PC has better performance and cheaper than PLC when operating and constructing the system. For many manufactures, these benefits alone are all the reason they need to switch from PLC-based system to RTOS-based system. To use the RTOS-based System, the PLC program needs the conversion to the RTOS task. And how to transform is the most important issue. So, we propose conversion method through the system model. The system model defines the operation of each module as the task after the system divided into module. Because the system divided into modules can control, the performance and the functionality of system improve, and the system can deal with a problem easily when repairing and changing.

• Composites Research
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• v.20 no.3
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• pp.43-49
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• 2007

Dynamic instability of rotating disks is the most significant factor to limit its rotating speed. Application of composite materials to rotating disks may enhance the dynamic stability leading to a possible design of rotating disks with lightweight and high speed. Whereas much work has been done on the effect of transverse shear and rotary inertia, called Timoshenko effect, on the dynamic behavior of plates, there is little work on the correlation between the effect and the rotation of disk, especially nothing in case of composite disks. The dynamic equations of a rotating composite disk are formulated with the Timoshenko effect and the vibrational analysis is performed by using a commercial package MSC/NASTRAN. According to the results, the Timoshenko effect goes seesaw in some modes, unlike the well-known fact that the effect decreases as the rotating speed increases. And it can be concluded, based only on the present results, that decrement of the Timoshenko effect by disk rotation grows larger as the thickness ratio decreases, the diameter ratio increases, the modulus ratio increases, and the mode number increases.

• The korean journal of orthodontics
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• v.52 no.2
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• pp.123-130
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• 2022

Objective: To evaluate if a remote digital monitoring system added at the end of orthodontic treatment could positively influence the retention phase by reducing the occurrence of misfit of removable appliances, number of emergency appointments (EA), and orthodontic relapse. Methods: Twenty-seven patients who completed active orthodontic treatment were divided into the study and control groups. In addition to the standard chairside follow-up appointments at month 1 (T1), month 3 (T2), month 6 (T3), the study group patients were monitored using Dental Monitoring^® with monthly intra-oral scans. Occurrence of misfit of removable retainers, number of EAs, and intercanine width change were recorded for both groups. Differences in EAs and retainer fit were assessed using the chi-square test. Intra-group and inter-group differences in the intercanine width were assessed with Friedman test and Mann-Whitney U test, respectively (α = 0.05). Results: The study group showed a significantly lower occurrence of misfit of removable retainers (p = 0.027) compared to the control group. No significant inter- and intra-group difference was found in the EAs and intercanine width change at each time-point. Conclusions: Integrating remote monitoring systems, such as Dental Monitoring^®, to the retention phase of the orthodontic treatment may lower the occurrence of misfit of removable retainers. However, a small sample size and a short observation period limit the strength of this evidence. These preliminary results tentatively suggest that remote monitoring technologies may be beneficial, especially during the COVID-19 pandemic, when the regularity of in-office visits might be disrupted.

• The Journal of Information Systems
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• v.32 no.1
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• pp.179-199
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• 2023

Purpose This study builds a prediction model to find stocks that can reach intrinsic value among KOSPI and KOSDAQ-listed companies to improve the stability and profitability of the stock investment. And investment simulations are conducted to verify whether stock investment performance is improved by comparing the prediction model, random stock selection, and the market indexes. Design/methodology/approach Value investment theory and machine learning techniques are applied to build the model. Various experiments find conditions such as the algorithm with the best predictive performance, learning period, and intrinsic value-reaching period. This study selects stocks through the prediction model learned with inventive variables, does not limit the holding period after buying to reach the intrinsic value of the stocks, and targets all KOSPI and KOSDAQ companies. The stock and financial data are collected for 21 years (2001-2021). Findings As a result of the experiment, using the random forest technique, the prediction model's performance was the best with one year of learning period and within one year of the intrinsic value reaching period. As a result of the investment simulation, the cumulative return of the prediction model was up to 1.68 times higher than the random stock selection and 17 times higher than the KOSPI index. The usefulness of the prediction model was confirmed in that the number of intrinsic values reaching the predicted stock was up to 70% higher than the random selection.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.29 no.3
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• pp.1-11
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• 2023

Background: The aim of this study was to compare the effects of squat training on an unstable support surface with different knee flexion angles on the balance ability of normal adults balance ability. Methods: 41 university students in their 20s attending N University in Cheonan, Chungcheongnam-do were divided into a 45-degree knee-bending squat training group and a 90-degree knee-bending squat training group. The groups trained on an unstable support surface 20 minutes per day, 3 times a week, for a total of 4 weeks. Results: Changes in static balance ability were not significant within and between the groups for both the sway distance and sway area in the eyes open and eyes closed states (p<.05). The changes in dynamic balance ability were significant in the forward, leftward, and rightward angles in both groups at the limit of stability (p<.05), but not significant in the backward angle (p>.05), and the comparison between groups was not significant (p>.05). Conclusion: No significant difference between static balance-related variables within and between the groups was found. Significant changes in dynamic balance-related variables within the groups were found but not between the groups. Therefore, in future studies, it is considered necessary to study various ages and differentiated intervention periods, such as young adults and the population of elderly people, with sufficient intervention periods to affect balance ability.