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Abstractπ‐Conjugated polyelectrolytes (CPEs) have been studied as interlayers on top of a separate hole transport layer (HTL) to improve the wetting, interfacial defect passivation, and crystal growth of perovskites. However, very few CPE‐based HTLs have been reported without rational molecular design as ideal HTLs for perovskite solar cells (PeSCs). In this study, the authors synthesize a triphenylamine‐based anionic CPE (TPAFS‐TMA) as an HTL for p‐i‐n‐type PeSCs. TPAFS‐TMA has appropriate frontier molecular orbital (FMO) levels similar to those of the commonly used poly(bis(4‐phenyl)‐2,4,6‐trimethylphenylamine) (PTAA) HTL. The ionic and semiconducting TPAFS‐TMA shows high compatibility, high transmittance, appropriate FMO energy levels for hole extraction and electron blocking, as well as defect passivating properties, which are confirmed using various optical and electrical analyses. Thus, the PeSC with the TPAFS‐TMA HTL exhibits the best power conversion efficiency (PCE) of 20.86%, which is better than that of the PTAA‐based device (PCE of 19.97%). In addition, it exhibits negligible device‐to‐device variations in its photovoltaic performance, contrary to the device with PTAA. Finally, a large‐area PeSC (1 cm2) and mini‐module (3 cm2), showing PCEs of 19.46% and 18.41%, respectively, are successfully fabricated. The newly synthesized TPAFS‐TMA may suggest its great potential as an HTL for large‐area PeSCs.

There are few studies on kinematic, kinematic, and energy consumption after robot training, so it is urgent to study this part. In a small retrospective open-label study, the results of spatiotemporal parameters and kinetic and kinematic analyzes of patients with chronic stroke in patients who underwent gait using an end-effector robot were compared with those of Gait speed, Cadence , Stride time, and stride speed, improvement of hip extension in kinematic analysis as a whole, and reduction of anterior tilting in pelvis. This suggests that robot-assisted gait training may improve the kinematic index Randomized Controlled Trial design is a systematic study. In addition, it is important to evaluate the energy expenditure and cardiorespiratory load of robot-assisted walking therapy for the rehabilitation of patients at risk of cardiovascular disease and stroke patients with impaired cardiopulmonary function. The purpose of gait therapy in stroke patients is to improve the efficiency of energy consumption by calibrating patterns of gait and asymmetry of gait movements. This is also an important issue for gait researchers. The authors reported that when using an end-effector type robot, the oxygen consumption was statistically significantly lower during the robot-assisted walking compared to when the robot was not assisted by the robot. During the walking with the exoskeleton type robot, and when compared to OTW (Overground treadmill walking) during ATW, there was a statistically significant decrease in mean oxygen consumption There was a report. However, previous researches did not compare the pre - treatment and post - treatment, but there is no report on the possibility of improvement of oxygen consumption after robot - assisted gait training. In this study, we divided the patients into two groups. One group was treated with 6-week gait training using an end-effector type robot-assisted walking device and the other group was treated with gait therapy for the same period of time. Six weeks after the end of the treatment, three-dimensional motion analysis, foot pressure analysis and energy consumption analysis were performed to obtain robot assisted training in terms of space time index, kinematics, kinematic index, dynamic EMG activation pattern, The purpose of this study was to investigate whether the improvement in walking performance and the energy consumption efficiency of walkers are more effective than the conventional walking training group. the three most natural walking cycles Calculate kinematical index and spatio-temporal index according to each gait cycle Dynamic EMG analysis Dynamic EMG was performed by attaching surface EMG to the skin using Medial GCM, Tibialis Anterior, Vastus Medialis, Rectus Femoris, Medial Hamstring, and Gluteus Maximus of both lower limbs using a wireless Delsys Trigno Sensor System (Delsys Inc, USA) Measure the signal and convert it to Root mean square (RMS). (Figure 5) EMG signal sampling rate: 2000 samples / sec Filter: EMG signal bandwidth 20- 450 Hz Surface electrode: Parallel bar electrode The measured EMG signals are obtained by measuring the duration and the period of activity according to the walking cycle and analyzing the degree of activation. 1. Medial GCM, Tibialis Anterior, Vastus Medialis, Rectus Femoris, Medial Hamstring, and Gluteus Maximus 2. Starting and ending points of muscle activation cycle 3. Muscle activation duration and RMS integral and peak value 4. The root mean square (RMS) value divided by 16 sections divided by time 5. Comparison between the right side and the left side 2-2. Energy consumption analysis Use K4b2 (COSMED, Italy) as a wearable metabolic system (Fig. 6) Measure O2 cost [ml / (m / kg)] and O2 rate (ml / min / kg) The walking distance was measured by walking with the self-selected gait velocity while wearing K4b2 (COSMED, Italy) for 5 minutes in total. The walking distance was measured for 3 minutes except the first 1 minute and the last 1 minute of oxygen consumption data for 5 minutes Using O2 rate and O2 cost 2-3. Foot pressure analysis The foot pressure was measured using a F-Scan system (Tekscan, USA) with a 0.16-mm thick, 980 force-sensing resistors (3.88 sensors per centimeter square) After inserting the pressure insoles, calibrate them according to the Tekscan user manual (Tekscan Research Software User Manual version 6.7 Rev. D, 2003) and measure them and analyze them as follows. 2-4. Fugl-Meyer Assessment(FMA) for Lower extremities 2-5. 10m walking test 2-6. Berg balance scale(BBS) 2-7. Timed up and go test(TUG) 2-8. Functional Ambulation Category(FAC) 2-9. Modified Ashworth Scale(MAS) 2-10. Rivermead Mobility Index(RMI) 2-11. Functional independence measure(FIM) Restoration of gait independence in stroke patients is one of the most important goals of rehabilitation therapy, and gait rehabilitation is one of the most important treatments in the treatment of stroke because it is a major factor affecting rehabilitation after stroke. In the rehabilitation of patients with post - stroke walking disorders, previous physical therapy was mainly manual therapy using therapist 's physical effort and walking training with walking aids. In recent years, however, emphasis has been placed on therapies based on motor learning concepts, which allow the patient to intensively train the exercise as closely as possible to the ultimate goal. The robot used for walking rehabilitation includes exoskeleton walking robot such as Lokomat® (Hocoma AG, Switzerland), Walkbot-G® (P & S Mechanics, Korea), MorningWalk® (Curexo, Korea) According to the Systematic Review, which compares two types of robot-assisted gait treatment divided into end-effector type, which is not an exoskeletal type such as System® (Rehatech, Switzerland) It has been reported that the percentage of patients who were able to walk independently when treated with a robot was higher than that of an exoskeleton-type robot. In this regard, in terms of acquisition of independent gait, studies on the therapeutic effect of the exoskeleton-type robot and the end-effector-type robot before and after the gait therapy were continuously performed, but 80% of the patients obtained independent gait, Despite the fact that many of these patients have abnormal walking, research has not yet been conducted. In previous studies, there was a statistically significant improvement in parameters of Gait speed, Cadence, and step length when compared with spatiotemporal parameters in training using exoskeleton robots for stroke patients. In another study, Gait speed and Cadence did not show a statistically significant improvement, and the effect on Gait speed and Cadence is still unknown. However, unlike exoskeletal robots, end-effector robotic gait training has been reported to improve Gait speed in most studies compared to conventional gait training. In addition, Cadence, Temporal symmetry ratio, Single, an improved side stride length, an improvement in the symmetry index of stance phase, and an improvement in Gait endurance. In this way, the end effector type robot walking training is more likely to improve walking quality than the exoskeleton type robot. The end-effector type robot, which is different from the exoskeleton type, reproduces the gait using the ankle joint to induce the movement of the knee joint and the hip joint. Therefore, it is possible to control the ankle joint, which is essential for improving the gait pattern. It is considered that the end effector type robot which can control the ankle joint is more likely to induce the improvement of the gait pattern than the existing exoskeleton type robot because it shows limitations in reproducing the ankle rocker motion.

Communicating the "97%"’ scientific consensus has been the centerpiece of the effort to persuade climate skeptics. Still, this strategy may not work well for those who mistrust climate scientists, to begin with. We examine how the American public---Republicans in particular---respond when provided with a relatively detailed causal explanation summarizing why scientists have concluded that human activities are responsible for climate change. Based on a preregistered survey experiment (N = 3007) we assessed the effectiveness of detailed causal evidence vs. traditional consensus messaging. We found that both treatments had noticeable effects on belief in human-caused climate change, with the causal evidence being slightly more effective, though we did not observe equivalent patterns in changes in attitudes toward climate policies. We conclude that conveying scientific information serves more as a remedy than a cure, reducing but not eliminating misperceptions about climate change and opposition to climate policies.

The potential of deoiled Azolla pinnata biomass (DAB) as electrode and substrate was evaluated for microbial fuel cell (MFC) operation. The anode electrode was fabricated using biochar obtained by subjecting DAB to pyrolysis at 600 °C, while the reducing sugars after hydrolysis of DAB by acid pretreatment was used as substrate. The post pyrolyzed biochar (P-DAB) was characterized for structural and elemental functionalities using SEM, XRD and Raman spectroscopy, whereas the reducing sugar obtained from hydrolyzed DAB (H-DAB) was analyzed for its composition. Experimental results indicated that at a given 3 g COD/L resulted in a voltage of 382 mV with 65.6% of COD reduction in closed circuit (CC) mode of operation. Cyclic voltammetric analysis depicted maximum oxidative and reductive peak currents of 3.42 mA and -4.0 mA. Noticeable peaks were also identified in CC (-0.2 V to +0.2 V and -0.19 V to -0.3 V) and OC (+0.2 V to +0.4 V and -0.1 V to -0.3 V) corresponding to complex IV cytochrome c couples (cytochrome Cox (Cyt Cox)/cytochrome Crd (Cyt Crd)), signifying the participation of electron carriers during electron transfer. The microbiome diversity showed dominance of Proteobacteria, a phylum known for exo-electrogenic bacterial species. The DAB-derived products account to environmental sustainability and support circular bioeconomy in a biorefinery mode.

Mobile edge computational power faces the difficulty of balancing the energy consumption of many devices and workloads as science and technology advance. Most related research focuses on exploiting edge server computing performance to reduce mobile device energy consumption and task execution time during task processing. Existing research, however, shows that there is no adequate answer to the energy consumption balances between multi-device and multitasking. The present edge computing system model has been updated to address this energy consumption balance problem. We present a blockchain-based analytical method for the energy utilization balance optimization problem of multi-mobile devices and multitasking and an optimistic scenario on this foundation. An investigation of the corresponding approximation ratio is performed. Compared to the total energy demand optimization method and the random algorithm, many simulation studies have been carried out. Compared to the random process, the testing findings demonstrate that the suggested greedy algorithm can improve average performance by 66.59 percent in terms of energy balance. Furthermore, when the minimum transmission power of the mobile device is between five and six dBm, the greedy algorithm nearly achieves the best solution when compared to the brute force technique under the classical task topology.

Abstract Bamboo has been considered a potential feedstock of energy for the future. It can be subjected to the pyrolysis for biofuels production. The thermogravimetric analysis (TGA) combined with differential thermogravimetric analysis (DTG) for bamboo was carried out prior to pyrolysis. The thermal degradation of bamboo was mainly between 230 and 420 °C. The conventional pyrolysis of bamboo was investigated in a bubbling fluidized-bed reactor using silica sand. The product distribution and composition of pyrolysis bio-oil were dependent on biomass component and operating conditions such as pyrolysis temperature, fluidization velocity, and particle size of biomass. The fractional catalytic pyrolysis of bamboo was also studied to upgrade the pyrolysis vapor, using HZSM-5 and red mud. The highest yield of bio-oil was 54.03 wt% compared to 49.14 wt% and 50.34 wt% of HZSM-5 and red mud catalyst, respectively. In the red mud catalytic pyrolysis, the oxygen content was rejected from pyrolysis vapor mostly via decarboxylation to produce more CO2 than CO; in contrast, for the HZSM-5 catalytic pyrolysis, the production of CO through decarbonylation was more favored than CO2. The main composition of catalytic pyrolysis bio-oil was 4-vinylphenol, which was employed as a raw material source to synthesize valuable material for energy storage.

Abstract A change in the thermal environment of an urban area affects health, living conditions, and energy consumption. In urban planning, urban parks are one of the methods for improving the thermal environment and saving cooling energy. Urban park construction can mitigate temperature, but it also causes urban development by increasing local attractiveness. To achieve efficient energy saving through parks in urban planning, the purpose of this study is to investigate the relationship between building energy consumption and urban characteristics both before and after the construction of an urban park. This study targeted Seoul's Gyeongui line forest, which was recently converted into a linear park on the former railway as an urban regeneration project. We analyzed the relationship between energy consumption and urban characteristics using a regression model, focusing on the changes before and after the construction. In this study, urban characteristics include environment, building physical characteristics, and economic variables. The results show that the construction of the urban park reduced not only temperature but also building energy consumption. The energy reduction effect of the park was limited to a marginal distance. Meanwhile, the urban park construction caused land prices to rise and prompted new development, and this changed the urban characteristics of the area and affected energy consumption. Despite changes in urban characteristics, urban park planning is an effective methods of reducing the energy consumption involved in cooling urban areas. We recommend comprehensive consideration of the urban factors when making park policy to reduce urban temperature and energy consumption.

To meet international efforts to prevent climate change, the South Korean government is seeking to transform its main power source from coal to natural gas (NG), which emits less carbon dioxide (CO2) than coal. The government needs information about public preferences for increasing NG-fired generation. Therefore, the purpose of this paper is to provide the government with this information by gathering the data on public preferences for increasing NG-fired generation for reducing CO2 emissions, analyzing these data, and obtaining the implications from the analysis. To this end, a survey of 1000 people, after explaining the merits and demerits of NG-fired power, were asked to determine the proper ratio of NG-fired generation by choosing one of six examples: lower than 10%, 10%–20%, 20%–30%, 30%–40%, 40%–50%, and higher than 50%. An interval data model was employed to deal with the data. The average value of the ratio was estimated to be 26.7% with statistical significance, which is greater than the actual value of 22.2% from 2017. Finally, whether and how much some variables such as education level, age, gender, and income level of the respondent affected their preferences for NG-fired generation were investigated.

Due to their high surface areas and large pore volumes, porous carbons (PCs) are valuable materials for use as electrodes in energy storage and conversion devices. Biomass is an ideal precursor for the preparation of PCs in part because it is sustainable and eco-friendly. Herein, new methodology for converting agarose, a naturally occurring type of biomass that forms robust hydrogels, into PCs with tunable pore structures and high electrochemical performance is described. The synthetic process is straightforward and entails heating a gel that is composed of agarose and potassium oxalate (K 2 C 2 O 4 ). Since the salt transforms into gaseous byproducts at elevated temperatures, the decomposition process was harnessed to create activated, open pores as the hydrogel underwent carbonization. For example, a PC with a surface area of 1754.9 m 2 g –1 and a pore volume of 2.643 cm 3 g –1 was obtained by heating a mixture of agarose and K 2 C 2 O 4 in a 1:3 weight ratio at 700 °C. The material was subsequently used as the electrode material in a supercapacitor and found to display a specific capacitance of 166.0 F g –1 at 0.125 A g –1 . Varying the quantity of added K 2 C 2 O 4 resulted in predictable changes in porosity and thus offered a means to tune the textural properties and the electrochemical performance of the PCs. For example, changing the feed ratio of agarose to K 2 C 2 O 4 to 1:6 afforded a PC that exhibited a high persistent specific capacitance (64.1 F g –1 at 5 A g –1 after 10,000 cycles) and a high-power density (20 kW kg –1 at 10 A g –1 ).