High-strength low-alloy steel is one of the widely used materials in onshore and offshore plant engineering. We investigated the alloying effect of solute atoms in α-Fe based alloy using ab initio calculations. Empirical equations were used to establish the effect of alloying on the Vicker’s hardness, screw energy coefficient, and edge dislocation energy coefficient of the steel. Screw and edge energy coefficients were improved by the addition of V and Cr solute atoms. In addition, the addition of trace quantities of V, Cr, and Mn enhanced abrasion resistance. Solute atoms and contents with excellent mechanical properties were selected and their thermal conductivity and thermal expansion behavior were investigated. The addition of Cr atom is expected to form alloys with low thermal conductivity and thermal expansion coefficient. This study provides a better understanding of the state-of-the-art research in low-alloy steel and can be used to guide researchers to explore and develop α-Fe based alloys with improved properties, that can be fabricated in smart and cost-effective manners.

Infrared radiation (IR) refers to the region of the electromagnetic radiation spectrum where wavelengths range from about 700 nm to 1 mm. Any object with a temperature above absolute zero (0 K) radiates in the infrared region, and a material that transmits radiant energy in the range of 0.74 to 1.4 um is referred to as a near-infrared optical material. Germanatebased glass is attracting attention as a glass material for infrared optical lenses because of its simple manufacturing process. With the recent development of the glass molding press (GMP) process, thermal imaging cameras using oxide-based infrared lenses can be easily mass-produced, expanding their uses. To improve the mechanical and optical properties of commercial materials consisting of ternary systems, germanate-based heavy metal oxide glasses were prepared using a melt-cooling method. The fabricated samples were evaluated for thermal, structural, and optical properties using DSC, XRD, and XRF, respectively. To derive a composition with high glass stability for lens applications, ZnO and Sb2O3 were substituted at 0, 1, 2, 3, and 4 mol%. The glass with 1 mol% added Sb2O3 was confirmed to have the optimal conditions, with an optical transmittance of 80 % or more, a glass transition temperature of 660 °C, a refractive index of 1.810, and a Vickers hardness of 558. The possibility of its application as an alternative infrared lens material to existing commercial materials capable of GMP processing was confirmed.

This study used optical and scanning electron microscopy to analyze the surface oxidation phenomenon that accompanies a γ'-precipitate free zone in a directional solidified CM247LC high temperature creep specimen. Surface oxidation occurs on nickel-based superalloy gas turbine blades due to high temperature during use. Among the superalloy components, Al and Cr are greatly affected by diffusion and movement, and Al is a major component of the surface oxidation products. This out-diffusion of Al was accompanied by γ' (Ni3Al) deficiency in the matrix, and formed a γ'-precipitate free zone at the boundary of the surface oxide layer. Among the components of CM247LC, Cr and Al related to surface oxidation consist of 8 % and 5.6 %, respectively. When Al, the main component of the γ' precipitation phase, diffused out to the surface, a high content of Cr was observed in these PFZs. This is because the PFZ is made of a high Cr γ phase. Surface oxidation of DS CM247LC was observed in high temperature creep specimens, and γ'-rafting occurred due to stress applied to the creep specimens. However, the stress states applied to the grip and gauge length of the creep specimen were different, and accordingly, different γ'-rafting patterns were observed. Such surface oxidation and PFZ and γ'-rafting are shown to affect CM247LC creep lifetime. Mapping the microstructure and composition of major components such as Al and Cr and their role in surface oxidation, revealed in this study, will be utilized in the development of alloys to improve creep life.

Tb3+-doped CaNb2O6 (CaNb2O6:Tb3+) thin films were deposited on quartz substrates at a growth temperature of 300 °C using radio-frequency magnetron sputtering. The deposited thin films were annealed at several annealing temperatures for 20 min and characterized for their structural, morphological, and luminescent properties. The experimental results showed that the annealing temperature had a significant effect on the properties of the CaNb2O6:Tb3+ thin films. The crystalline structure of the as-grown CaNb2O6:Tb3+ thin films transformed from amorphous to crystalline after annealing at temperatures greater than or equal to 700 °C. The emission spectra of the thin films under excitation at 251 nm exhibited a dominant emission band at 546 nm arising from the 5D4 → 7F5 magnetic dipole transition of Tb3+ and three weak emission bands at 489, 586, and 620 nm, respectively. The intensity of the 5D4 → 7F5 (546 nm) magnetic dipole transition was greater than that of the 5D4 → 7F6 (489 nm) electrical dipole transition, indicating that the Tb3+ ions in the host crystal were located at sites with inversion symmetry. The average transmittance at wavelengths of 370~1,100 nm decreased from 86.8 % at 700 °C to 80.5 % at an annealing temperature of 1,000 °C, and a red shift was observed in the bandgap energy with increasing annealing temperature. These results suggest that the annealing temperature plays a crucial role in developing green light-emitting CaNb2O6:Tb3+ thin films for application in electroluminescent displays.

In this study, changes in the microstructure and mechanical properties of cast and extruded Al-2Li-1Ce alloy materials were investigated as the Mg content was varied. The density decreased to 2.485, 2.46 and 2.435 g/cm3 when the Mg content in the Al-2Li-1Ce alloy was increased to 2, 4 and 6 wt%, respectively. Intermetallic compounds of Al11Ce3 were observed in all alloys, while the β-phase of Al3Mg2 was observed in alloys containing 6 wt% of Mg. In the extruded material, with increasing Mg content the average grain size decreased to 84.8, 71.6 and 36.2 μm, and the fraction of high-angle grain boundaries (greater than 15°) increased to 82.8 %, 88.6 %, and 91.8 %, respectively. This occurred because the increased Mg content promotes dynamic recrystallization during hot extrusion. Tensile test results showed that as the Mg content increased, both the yield strength and tensile strength increased. The yield strength reached 86.1, 107.3, and 186.4 MPa, and the tensile strength reached 215.2, 285, and 360.5 MPa, respectively. However, it is worth noting that the ductility decreased to 27.78 %, 25.65 %, and 20.72 % as the Mg content increased. This reduction in ductility is attributed to the strengthening effect resulting from the increased amount of dissolved Mg, and grain refinement due to dynamic recrystallization.

A solution combustion process for the synthesis of hollandite (BaAl2Ti6O16) powders is described. SYNROC (synthetic rock) consists of four main titanate phases: perovskite, zirconolite, hollandite and rutile. Hollandite is one of the crystalline host matrices used for the disposal of high-level radioactive wastes because it immobilizes Sr and Lns elements by forming solid solutions. The solution combustion synthesis, which is a self-sustaining oxi-reduction reaction between a nitrate and organic fuel, generates an exothermic reaction and that heat converts the precursors into their corresponding oxide products in air. The process has high energy efficiency, fast heating rates, short reaction times, and high compositional homogeneity. To confirm the combustion synthesis reaction, FT-IR analysis was conducted using glycine with a carboxyl group and an amine as fuel to observe its bonding with metal element in the nitrate. TG-DTA, X-ray diffraction analysis, SEM and EDS were performed to confirm the formed phases and morphology. Powders with an uncontrolled shape were obtained through a general oxide-route process, confirming hollandite powders with micro-sized soft agglomerates consisting of nano-sized primary particles can be prepared using these methods.

Exploring earth-abundant, highly effective and stable electrocatalysts for electrochemical water splitting is urgent and essential to the development of hydrogen (H2) energy technology. Iron-cobalt layered double hydroxide (FeCo-LDH) has been widely used as an electrocatalystfor OER due to its facile synthesis, tunable components, and low cost. However, LDH synthesized by the traditional hydrothermal method tends to easily agglomerate, resulting in an unstable structure that can change or dissolve in an alkaline solution. Therefore, studying the real active phase is highly significant in the design of electrochemical electrode materials. Here, metal-organic frameworks (MOFs) are used as template precursors to derive FeCo-LDH from different iron sources. Iron salts with different anions have a significant impact on the morphology and charge transfer properties of the resulting materials. FeCo-LDH synthesized from iron sulfate solution (FeCo-LDH-SO4) exhibits a hybrid structure of nanosheets and nanowires, quite different from other electrocatalysts that were synthesized from iron chloride and iron nitrate solutions. The final FeCo-LDH-SO4 had an overpotential of 247 mV with a low Tafel-slope of 60.6 mV dec-1 at a current density of 10 mA cm-2 and delivered a long-term stability of 40 h for the OER. This work provides an innovative and feasible strategy to construct efficient electrocatalysts.

Background: Pain neuroscience education (PNE) combined with exercise and mobilisation with cognitive goals presented decreases in pain and disability and an increase in spinal function compared to physiotherapy intervention in patients with chronic low back pain (CLBP). Objectives: To investigated the effect of forward head posture (FHP) with chronic neck pain on the PNE combined with cervical and thoracic mobilization. Design: A randomized controlled trial. Methods: The subjects were randomly allocated to the MDT with PNE group (MPNEG, n=15) and the PNE group (PNEG, n=15). Pain neuroscience education was provided to both groups, and MDT exercise was additionally performed in the experimental group. Training was conducted 3 times a week for 8 weeks, and the Oswestry Disability Index (ODI) and numeric rating scale (NRS) were used to measure the level of back pain dysfunction, and each was evaluated before and after the experiment. Results: Results from the study indicated that statistically significant decrease in NRS and ODI in MPNEG. In PNEG, there was statistically significant decrease in NRS. And in MPMES, there was a statistically significant decrease in ODI than in PNEG. Conclusion: The MDT combined with PNE is more effective than PNE alone as a treatment method for improving lumbar dysfunction and reducing pain in chronic low back pain.

Background: Outcome measures (OMs) are essential components of evidence- based practice as they help in implementing interventions and assessing changes in a patient's status before and after treatment. However, many therapists do not utilize OMs in their practice, and research on the factors that influence physical therapists' decisions regarding the use of OMs primarily consists of quantitative or survey-based studies. Objectives: The purpose of this study was to select research studies on OMs use among physical therapists through a systematic review, identify questionnaire characteristics, and assess the quality of items collection and research. Design: A systematic review. Methods: This study systematically collected survey studies on the use of OMs from five databases (KMBase, RISS, KCI, Pubmed, and Cochrane) based on the criteria of PRISMA's systematic review flowchart. The quality of the studies was assessed using the AXIS Tool. Results: A total of eight studies were selected. In most of the studies, the questionnaires were developed internally, validated through preliminary research, and reliability testing was not conducted. The items used within OMs were divided into 10 categories, with the highest frequency of questions centering around how to use OMs, and the lowest frequency regarding work environment and reasons. All eight studies were determined to be of good quality. Conclusion: The collected OMs questionnaires revealed variations in the item frequency. Future qualitative research and participant feedback are needed to develop a consistent questionnaire and validate its validity and reliability.

Background: Choosing to perform squats on an unstable surface potentially offers advantages surpassing those of their stable counterpart. Objectives: The purpose of this study was to compare muscle activation during squats on stable and unstable surfaces and investigate the relationship among thigh muscles. Design: Observational study. Methods: Nineteen adults participated in this study. The stable surface consisted of a flat floor. The unstable surface involved the use of an air cushion. An air cushion was positioned beneath each foot of the study participants. Surface electromyography was employed to measure muscle activation. %MVC was calculated by measuring muscle activation during squat execution and manual muscle testing. Results: The comparison of muscle activation during squats between stable and unstable surfaces revealed a significant difference in the rectus femoris and biceps femoris (P<.05). On stable surfaces, positive correlations were observed in the rectus femoris, vastus lateralis, and vastus medialis (P<.05). On unstable surfaces, positive correlations were found between the rectus femoris and vastus medialis (P<.05). Conclusion: This study observed an increase in muscle activation of the rectus femoris and biceps femoris during squats on an unstable support surface compared to a stable support surface.

Background: Floor sit-to-stand (FSTS) places a higher load on the knees than chair sit-to-stand (CSTS). It is difficult to experimentally measure the maximum knee joint force during sit-to-stand motion. Objectives: This study's objectives were twofold: firstly, to quantify the differences in knee joint force between FSTS and CSTS, and secondly, to identify the angles at which the maximum knee joint force occurs during these motions. Design: Computer simulation study. Method: This study was conducted on 4 adult male subjects in their 20s. The FSTS and CSTS motion trajectories of the subjects were acquired using 3- dimensional motion analysis equipment. Using these, the human body mass model of the program was modified according to the subject, and the knee joint force was calculated. Also, the knee angle at which the maximum knee joint force occurs was found. Results: When the subjects performed the FSTS motion, a knee joint force that was up to about 160% higher than that of the CSTS motion occurred, and the angle at which the maximum knee joint force occurred was different between the sitting sequence(FSTS motion: 56~58 degree, CSTS motion: 78~82 degree) and the standing sequence(FSTS motion: 98~100 degree, CSTS motion: 70~74 degree). Conclusion: By comparing FSTS motion with CSTS motion, it is expected that it can be used as a quantitative guide for the effect of motion similar to FSTS motion on the knee when prescribing exercise for the elderly or patients with knee-related lesions.

Background: As ways to optimize the mobilization of postural stability muscles for sitting up motions, arm reaching motions and head raising motions have important effects. Objectives: This study was conducted to investigate the effects of reaching to sit-up training on the trunk muscle activity, postural ability, and balance ability of patients with hemiplegia due to stroke. Design: Randomized controlled trial. Methods: This study was conducted with 18 stroke patients who met the selection criteria divided into two groups: a study group of 9 patents and a control group of 9 patients. The study group carried out reaching to sit-up training, which can promote trunk muscles and improve control through trunk interactions. The control group received general physical therapy intervention Results: The activity of the trunk muscle was significantly different before and after intervention in study and control group. The functional reaching test showed significant changes in both the study group and the control group. The timed up and go test showed a significant change in the study group. Conclusion: Reaching to sit-up training for 4 weeks showed increases in trunk muscle activity in stroke patients and was effective in improving balance ability.

Background: ErigoPro enables acute stroke patients to carry out stable weight-bearing training with gradual verticalization. Study on the effectiveness of robotic assisted treatment equipment for chronic patients is insufficient. Objectives: This study aims to investigate the effect of dynamic vertical posture training using ErigoPro on trunk alignment and balance in chronic stroke patients. Design: Randomized controlled trial. Methods: The subjects of this study were 30 patients were randomly assigned to a study group of 15 patients and a control group of 15 patients. The study intervention was carried out for 50 minutes per day consisting of 30 minutes of general neuro-physiotherapy and 20 minutes of ErogoPro training, 3 times a week for 8 weeks. Results: The study group showed difference in trunk inclination (P<.05), kyphotic angle (P<.05), lateral deviation of the spine (P<.05), thoracic angle (P<.01), timed up and go test (P<.01), Berg balance score (P<.01). There was a significant difference between the groups in the trunk inclination (P<.05), timed up and go test (P<.01), Berg balance score (P<.05). Conclusion: It could be seen that the treatment combined with ErigoPro training for 8 weeks was effective in restoring trunk alignment and improving balance ability in chronic stroke patients.

Background: Proprioception in the ankle joint is important for maintaining balance. There is a correlation between joint position sense (JPS), balance and ankle dorsiflexion range of motion (DF-ROM). Objectives: The purpose of this study was to compare the effects of talocrural joint mobilization (TJM) and muscle energy technique (MET) of plantar flexor muscle (PF) on improving joint position sense (JPS) and static balance. Design: Cross-over randomized trial research. Methods: Sixteen participants (male 10, female 6; 20’s of their age) without ankle instability were recruited. In a randomized, three conditions, no intervention, talocalcaneal mobilization, and PF-MET were all applied to 16 participants. For TJM, the Kaltenborn grade 3 joint gliding method, in which the talus moves posteriorly perpendicular to the tacrocrural joint plane, were used. In the PF-MET, MET method were applied gastrocnemius muscle and soleus muscle with 25% of 1 Repeat Maximum of each muscle. The all participants performed PF-MET and TJM for 18 minutes. DF-ROM measured the weightbearing lunge test. JPS measured using the active joint angle reproduction test. Static balance was measured displacement of center of pressure parameter. Results: PF-MET and TJM had significant differences in DF-ROM and AP displacements. PF-MET significantly increased at 5° and 15° of plantar flexion and 5° of dorsiflexion, and COP velocity significantly decreased in JPS compared to TJM. Conclusion: PF-MET and TJM are effective in increasing DF-ROM. However, PF-MET has a more positive effect on improving JPS and static balance than on talocrural joint mobilization.

Background: A decrease in physical activity has been observed due to the global pandemic, resulting in the onset and progression of musculoskeletal disorders as chronic diseases. Objectives: This study aimed to assess the difference in the degree of contraction of the lower limb muscles between the existing vertical vibration method and a new cross-vibration method. Design: Randomized controlled trial. Methods: The exercise program using whole-body vibration equipment was conducted for 12 sessions, 25 min per session, three times per week for 4 weeks. Results: The changes over time showed a significant difference in cross-alternating vibrations (P<.05), except for the lateral gastrocnemius and tibialis anterior, with no significant difference in sonic vertical vibration (P>.05). The interaction between time and group was significant for all muscles (P<.05), except for the biceps femoris, with differences between before the program and at 2 and 4 weeks after the program revealed in the post-hoc analysis. Conclusion: Future studies should further evaluate the use of CAV exercise devices as auxiliary equipment in exercise by assessing different groups and variations in intensity.

Background: Some patients may not fully recover their daily activity capabilities even after the total hip replacement (THR), and may continue to experience functional limitations for up to a year after the procedure, according to reports. Objectives: The purpose of this study was to examine the effects of machine squat on muscle strength, balance and gait in patients after THR. Design: A randomized controlled trial. Methods: Thirty-three patients after THR were randomly allocated into slide (n=11), reformer (n=11), and control groups (n=11). Each group underwent their respective squat regimens for thirty minutes, seven times a week, for two weeks. Muscle strength changes were assessed using the manual muscle test (MMT), balance was evaluated using the Berg Balance Scale (BBS), and gait analysis was performed using the 10-meter walk test (10MWT). Results: Significant changes in hip flexor and abductor strength were observed in the slide and reformer groups within each group (P<.05). The reformer group showed significant changes in hip extensor strength (P<.05). Significant improvements in BBS were observed in all three groups (P<.05). There were significant changes in 10MWT in the slide and reformer groups (P<.05). A significant difference in hip extensor strength was found between the reformer and control groups after the intervention (P<.0167). Significant differences in BBS were observed between the slide and reformer groups and between the reformer and control groups after the intervention (P<.0167). Conclusion: Our findings suggest that machine squat regimens can be effective for early rehabilitation after THR, improving muscle strength, balance, and gait.

Background: Junior colleges have been establishing plans for the development of start-up education for students and have been providing various educational programs to support students’ start-up businesses. Objectives: The effects of entrepreneurship and entrepreneurial self-efficacy on the start-up intention of college physical therapy students were analyzed. Design: Questionnaire design. Methods: Surveys on entrepreneurship, entrepreneurial self-efficacy, and start-up intention were conducted with 269 college physical therapy students, and the levels of individual measurement variables, correlations, and variables affecting start-up intention were analyzed. Results: College physical therapy students showed differences in start-up intention between genders, and male students tended to have a higher startup intention (P<.001) than female students. The correlations among the major variables were analyzed. According to the results, all sub-factors of start-up intention had significant positive correlations with all sub-factors of entrepreneurship and entrepreneurial self-efficacy (P<.05). In addition, multiple regression analysis was conducted to identify factors affecting start-up intention. Start-up education was shown to have no direct effect on start-up intention. Innovation (β=.238, P=.000), risk sensitivity (β=.228, P=.000), and initiative (β=.220, P=.001), which are sub-factors of entrepreneurship, were shown to have effects on start-up intention. Self-regulated efficacy (β=-.193, P=.039) and task challenge (β=.210, P=.004), which are sub-factors of entrepreneurial self-efficacy, were found to have effects on start-up intention. Conclusions: To boost the start-up intention of college physical therapy students and induce their start-ups, customized start-up education that considers entrepreneurship level and gender is necessary.

Transparent conductive tungsten (W) doped indium oxide (In2O3; IWO) films were deposited at different substrate bias voltage (-Vb) conditions at room temperature on glass substrates by radio frequency (RF) magnetron sputtering and the influence of the substrate bias voltage on the optical and electrical properties was investigated. As the substrate bias voltage increased to -350 Vb, the IWO films showed a lower resistivity of 2.06 × 10-4 Ωcm. The lowest resistivity observed for the film deposited at -350 Vb could be attributed to its higher mobility, of 31.8 cm2/Vs compared with that (6.2 cm2/Vs) of the films deposited without a substrate bias voltage (0 Vb). The highest visible transmittance of 84.1 % was also observed for the films deposited at the -350 Vb condition. The X-ray diffraction observation indicated the IWO films deposited without substrate bias voltage were amorphous phase without any diffraction peaks, while the films deposited with bias voltage were polycrystalline with a low In2O3 (222) diffraction peak and relatively high intensity (431) and (046) diffraction peaks. From the observed visible transmittance and electrical properties, it is concluded that the opto-electrical performance of the polycrystalline IWO film deposited by RF magnetron sputtering can be enhanced with effective substrate bias voltage conditions.

In this study we examine variations in the structure of perovskite compounds of LaBa2Cu2O9, LaBa2CaCu3O12 and LaBa2Ca2Cu5O15 synthesized using the solid state reaction method. The samples’ compositions were assessed using X-ray fluorescence (XRF) analysis. The La: Ba: Ca: Cu ratios for samples LaBa2Cu2O9, LaBa2CaCu3O12 and LaBa2Ca2Cu5O15 were found by XRF analysis to be around 1:2:0:2, 1:2:1:3, and 1:2:2:5, respectively. The samples’ well-known structures were then analyzed using X-ray diffraction. The three samples largely consist of phases 1202, 1213, and 1225, with a trace quantity of an unknown secondary phase, based on the intensities and locations of the diffraction peaks. According to the measured parameters a, b, and c, every sample has a tetragonal symmetry structure. Each sample’s mass density was observed to alter as the lead oxide content rose. Scanning electron microscope (SEM) images of the three phases revealed that different Ca-O and Cu-O layers can cause different grain sizes, characterized by elongated thin grains, without a preferred orientation.

This study focuses on how the partial substitution of copper by nickel nanoparticles affects the electrical and structural properties of the Bi2Ba2Ca2Cu2.9Ni0.1O10+δ, Bi2Ba2Ca2Cu2.8Ni0.2O10+δ and Bi2Ba2Ca2Cu2.6Ni0.4O10+δ compounds. Approximate values of crystallization size and crystallization percentage for the three compounds were calculated using the Scherer, modified Scherer, and Williamson-Hall methods. A great similarity was observed in the crystal size values from the Scherer method, 243.442 nm, and the Williamson-Hall method, 243.794 nm for the second sample. At the same time this sample exhibited the highest crystal size value for the three methods. In the examination of electrical properties, the sample with 0.1 partial substitution, Bi2Ba2Ca2Cu2.9Ni0.1O10+δ was determined to be the best with a critical temperature of 100 K and an energy gap of 6.57639 × 10-21 MeV. Using the SEM technique to analyze the structural morphology of the three phases, it was discovered that the size of the granular forms exceeds 25 nm. It was determined that the samples’ shapes alter when nickel concentration rises. The patterns that reveal the distribution of the crystal structure also exhibit clear homogeneity.