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Hyperparameter tuning is crucial in the development of machine learning models. This study introduces the nonlinear shrinking factor and the Cauchy mutation mechanism to improve the Dujiangyan Irrigation System Optimization (DISO), proposing the improved Dujiangyan Irrigation System Optimization algorithm (IDISO) for hyperparameter tuning in machine learning. The optimization capabilities and convergence performance of IDISO were validated on 87 CEC2017 benchmark functions of varying dimensions and nine real-world engineering problems, demonstrating that it significantly outperforms DISO in terms of convergence speed and accuracy, and ranks first in overall performance among the seventeen advanced metaheuristic algorithms being compared. To construct a robust and generalizable prediction model for hydrochar element characteristics, this study utilized IDISO and DISO algorithms to fine-tune the parameters of the XGBoost model. The experimental results show that the IDISO-XGBoost model achieved an average prediction performance of 0.95, which represents a 4% improvement over the DISO-XGBoost model. These results indicate that the IDISO algorithm has significant potential and value in practical applications. [ABSTRACT FROM AUTHOR]

The geometric shape of the roof and the opening position are important parameters influencing the internal cross-ventilation of buildings. Although there has been extensive research on natural ventilation, most of it has focused on flat or sloping roofs with the same opening positions. There is still limited research on the impact of different opening positions and sloping roofs on natural ventilation. In this study, computational fluid dynamics (CFD) was used to investigate the air exchange efficiency (AEE) in general isolated buildings. These buildings encompassed three distinct opening configurations (top–top, top–bottom, and bottom–top) and six varying slope angles for gable roofs (0°, 9°, 18°, 27°, 36°, and 45°). Computational simulations were carried out using the SST k-omega turbulence model, and validation was performed against experimental data supplied by the Japanese AIJ Wind Tunnel Laboratory. Grid independence validation was also conducted to ensure the reliability of the CFD simulation results. The study revealed that the highest AEE was 48.1%, achieved with the top–bottom opening configuration and a gable roof slope angle of 45°. Conversely, the lowest AEE was 31.4%, attained with the bottom–top opening configuration and a gable roof slope angle of 27°. Furthermore, it was observed that when the opening configuration was set to top–top and bottom–top, the slope angle of the gable roof had minimal influence on AEE, with an average AEE of only around 33%. When the opening configuration was top–bottom, it was found that there was a positive correlation between the gable roof slope angle and AEE. [ABSTRACT FROM AUTHOR]

News media can influence citizens' health beliefs about COVID-19 and eventually their vaccination intention. However, existing literature has rarely investigated how such effect is contingent upon a country-level factor: press freedom. Situated in the Health Belief Model, this study draws upon a multi-national survey (N = 3,599), involving 10 major cities in Asia to address the research gap. Results showed that news exposure has a positive effect on personal health beliefs on COVID-19, affecting their vaccination intention. More interestingly, the relationship between news exposure and personal health beliefs about COVID-19 was negatively moderated by level of press freedom – that is, the relationship between news exposure and personal health beliefs is stronger in cities that belong to countries with low levels of press freedom. [ABSTRACT FROM AUTHOR]

In this letter, we investigate the trade-off between parasitic capacitance and parasitic resistance of lattice-matched InP high-electron mobility transistors (HEMTs) with a double-recessed gate process. Lg = 80 nm HEMTs with and without SiO2 hardmask are used to adjust parasitic capacitance and parasitic resistance. And their DC and RF responses are measured and analyzed, such as the maximum transconductance (gm_max), ON-resistance (RON), current-gain cutoff frequency (fT), and maximum oscillation frequency (fmax). In order to obtain a high fmax, we adopt the technology of gate recess closer to the source electrode. The device with SiO2 hardmask, which has relatively smaller parasitic resistance, exhibits excellent characteristics of RON = 0.54 Ω·mm, gm_max = 1.087 S/mm, fT = 304 GHz, and fmax = 524 GHz. The device without the SiO2 hardmask achieved smaller drain output conductance (gds) and the ratio of gate-to-drain (Cgd) to gate-to-source (Cgs), resulting in a larger fmax of 690 GHz without significantly lowering fT (285 GHz). The HEMTs are providing more options for circuit processing. [ABSTRACT FROM AUTHOR]

The use of straw biomass for energy can reduce the use of fossil energy and alleviate air pollution. Herein, the cohydrothermal carbonization (Co‐HTC) of rice straw and wheat straw with corn straw is investigated, and synergistic effects of multistraw biomass are observed in the Co‐HTC process. When the corn straw ratio is 75%, the energetic recovery efficiency, C content, and heating value increase compared to the calculated values of the Co‐HTC products. At 260 °C, the energetic recovery efficiency increases by 8.96% and the heating value increases by 2.28 MJ kg−1, which is beneficial for its application. The positive synergistic effect is probably caused by the enhanced dehydration and decarboxylation reactions. For the combustion behavior analysis, the entire combustion process is divided into two stages. When the corn straw ratio is greater than 50%, compared to the calculated values of the Co‐HTC products, the comprehensive combustibility index and activation energy of stage I increase and the activation energy of stage II decreases at 180 °C, while the activation energy of stage I decreases and the activation energy of stage II increases at 260 °C. These findings demonstrate that the Co‐HTC of multistraw biomass is suitable for solid biofuel production. [ABSTRACT FROM AUTHOR]

We proposed a dual typology of audiences for social media communication campaigns: the participating audience , who interacts with campaign planners, and the observing audience , who observes those interactions. Situated in a context of promoting seeking counseling for depression, our online experiment (N  =   570) demonstrated that the similarity of the observing and participating audiences (high vs. low), the message features of campaign planners' replies (high person-centeredness vs. low person-centeredness vs. no reply), and the observing audience's predispositions (with vs. without depressive symptoms) jointly affected the observing audience's attitude toward seeking counseling. For observers with depressive symptoms, seeing a campaigner addressing a negative comment that reflects a similar concern of their own mitigated the adverse impact of the comment on the observers' attitude. Our findings introduce a theoretical lens for understanding a communication process unique to campaigns on social media and offer insights into how the process shapes campaigns' intended responses. [ABSTRACT FROM AUTHOR]

A physical insight into the capture and emission behavior of interface/oxide states in a GaN-based metal-oxide-semiconductor (MOS) structure is of great importance to understanding the threshold voltage (VTH) instability in GaN power transistors. A time-dependent VTH shift in Ni/Al2O3/AlGaN/GaN MOS-HFETs (heterojunction field-effect transistors) and a distribution of Al2O3/III-nitride interface states (Dit) were successfully characterized by constant-capacitance deep level transient spectroscopy. It is found that in situ remote plasma pretreatments in plasma-enhanced atomic-layer-deposition could suppress Dit (EC-ET > 0.4 eV) down to below 1.3 × 1012 cm−2 eV−1. Under high applied gate bias (e.g., VG > 8 V), tunnel filling of oxide states in the Al2O3 dielectric comes into play, contributing to remarkable VTH instability in the MOS-HFETs. The tunnel distance between the 2D Electron Gas (2DEG) channel and oxide states ET,ox in the Al2O3 dielectric decreases from 3.75 to 0.82 nm as VG increases from 2 to 8 V. A further increase of VG to 11 V makes the Fermi level approach ET,ox (EC − ET ∼ 1.62 eV), which may enable direct filling. High electric field induced tunnel filling of gate oxide states could be an assignable cause for VTH instability in normally-OFF III-nitride MOS-HFETs. [ABSTRACT FROM AUTHOR]

Following the COVID-19's outbreak in China, wildlife-related issues such as wildlife management and conservation made headlines around the world due to the potential zoonotic nature of the newly discovered coronavirus. In our study, we examined the dynamic interaction of the news agenda and public agenda concerning wildlife-related issues on social media after COVID-19's outbreak. Using big data analytics, we automatically extracted the agendas' attributes and networks from 110,549 social media posts made from January 1 to April 8, 2020, and investigated the effect of second- and third-level dynamic agenda setting in a time series analysis. Our findings suggest that the agenda-setting effect of wildlife-related issues on social media was not a single-step, unidirectional action but a reciprocal, dynamic interaction constantly constructed by news outlets and the general public. [ABSTRACT FROM AUTHOR]

In this study, we tested the core premise of the risk perception attitude framework—that perceived risk and perceived efficacy jointly affect intention—and identified consideration of future consequences (CFC) as a boundary condition of the premise in the context of mitigating climate change. Our two-wave survey (N = 439) revealed that perceived individual-level efficacy predicted intention to perform individual behavior, whereas perceived societal-level risk predicted intention to engage in collective action. For individuals with low CFC, perceived risk and perceived efficacy's joint effect was positively associated with intention to engage in individual behavior and collective action against climate change. [ABSTRACT FROM AUTHOR]

Prefabrication as a sustainable construction method has become a trend for use in house construction. However, the construction of rural houses in China still mainly adopts on-site construction, which also raises wasteful resources and environmental problems. Previous studies lack an evaluation system for the implementation potential of prefabricated rural housing in counties, and thus cannot provide references for the government to formulate implementation strategies. This study uses PEST analysis to establish an evaluation index system for the implementation potential of prefabricated rural housing and then evaluates 32 counties in Chongqing with urbanization rates below 90% based on the entropy weighted TOPSIS model. The results show that the weight values of the four evaluation subsystems of political, economic, social, and technological are 0.4516, 0.3152, 0.0684, and 0.1648, respectively; the nearness degrees of Dianjiang, Yubei, Jiangjin, and Rongchang are 0.5475, 0.4439, 0.4312, and 0.4103, respectively, ranking in the top four in Chongqing. The results indicate that the potential of implementing prefabricated rural housing in Chongqing is closely related to policy orientation and construction industrialization; Dianjiang, Yubei, Jiangjin, and Rongchang have the relative advantage of implementing prefabricated rural housing. Finally, this paper proposes political, economic, social, and technological suggestions for the implementation of prefabricated rural housing in Chongqing. [ABSTRACT FROM AUTHOR]

To identify the psychosocial determinants of individuals' intention to engage in collective actions against cancer, we extended and tested the risk perception attitude (RPA) framework at the level of social perceptions. The results of a large online survey of Hong Kong citizens (N = 1,005) revealed that perceived societal risk and perceived collective efficacy directly and jointly influenced respondents' intention to engage in collective actions against cancer, namely donating to cancer charities, volunteering at cancer-prevention organizations, and supporting public policies for cancer prevention. However, the interaction between perceived societal risk and perceived collective efficacy occurred in a direction opposite to the direction in the initial RPA framework. As suggested by the framework, we also categorized individuals into four attitudinal groups based on their perceptions of societal-level risk as well as efficacy and compared their demographic and psychological characteristics. Among the findings, the four groups significantly differed in their perceptions of individual-level risk as well as efficacy, in their family cancer history, and in their intentions to engage in individual-level behaviors to prevent cancer. Altogether, our findings contribute to the literature by extending the RPA framework to individuals' societal-level perceptions and by providing evidence that the framework can benefit the development of health communication campaigns to promote engagement in collective actions to support cancer prevention. [ABSTRACT FROM AUTHOR]

Online information seekers often do not actively post or engage in interactions with others, inviting research on how passive users of online communities benefit from the information they see. Based on the social identity model of deindividuation effects model (SIDE) and social identity theory, we proposed and tested the idea that observers of a supportive interaction online could relate to the observed support seeker based on their shared gender and, in turn, become vicariously influenced by the support provider's message to the support seeker. An experiment using a sample of young adults (N   =   326) in the United States provided support to the proposition. Furthermore, the outcomes of the vicarious interaction were qualified by the genders of the observed interactants and enhanced by the lack of profile photos. The findings advance the understandings of vicarious interaction in online context and guide the design of online communities to promote mental well-being. Lay Summary Ample evidence shows that people benefit tremendously from participating in online health support communities, but less is understood about how people who do not actively participate in interactions benefit from these communities. We conducted an online experiment using a sample of young adults in the United States. The results showed that females, compared with males, are more likely to be persuaded to seek professional counseling for mental health issues from observing a supportive conversation online. The persuasive effect of reading supportive interactions was enhanced when female participants shared the same gender with the observed support seeker and when the observed interactants had no profile photos. [ABSTRACT FROM AUTHOR]

An unrecoverable degradation of gate leakage is observed in AlGaN/GaN high electron mobility transistors (HEMTs) under high OFF‐state drain bias stress up to 200 V. Current‐mode deep‐level transient spectroscopy is developed for in situ observation of evolution of traps in the HEMTs before and after stress. It is revealed that two discrete traps, with activation energy of 0.54 and 0.69 eV, have converted into a deeper and broader trap (0.86 eV) after the stress, along with an increased apparent capture cross section (from 1.71 × 10−17–1.11 × 10−15 cm2 to 9.05 × 10−15 cm2). The conversion lowers down the tunneling barrier between metal and the AlGaN barrier, which facilitates trap‐assisted gate leakage in reversed biased AlGaN/GaN HEMTs. Engineering of deep traps in the AlGaN/GaN epilayers is essential for promoting and upgrading of power capability of GaN‐based RF HEMTs. [ABSTRACT FROM AUTHOR]

Herein, the effect of metal contact doping on the scaled graphene field effect transistor (GFET) is investigated. Different from the traditional semiconductors device, the drain current of GFET is not inversely proportional to the channel length (LCH). The abnormal scaling behavior for drain current in GFETs can be attributed to the modification of channel resistance induced by the penetration of contact metal doping. In addition, the field‐effect mobility (μEF) of long channel GFET trend to saturate with decreasing LCH, which is consistent with the diffusive transport model. As the channel length is further scaled down, the μEF at first increases drastically and then decreases due to the enhanced effect of electrical property of graphene under the metal electrode as well as the contact resistance on the carrier transport of GFET. This study indicates that there will be a trade‐off between scaled channel length and the best performance of GFET. Further efforts should be made to modulate the properties of graphene both in channel and contact region to improve the scaling behavior of GFET. [ABSTRACT FROM AUTHOR]

The gate insulator is one of the most crucial factors determining the performance of a graphene field effect transistor (GFET). Good electrostatic control of the conduction channel by gate voltage requires thin gate oxides. Due to the lack of the dangling bond, a seed layer is usually needed for the gate dielectric film grown by the atomic layer deposition (ALD) process. The seed layer leads to the high-quality deposition of dielectric films, but it may lead to a great increase in the thickness of the final dielectric film. To address this problem, this paper proposes an improved process, where the self-oxidized Al2O3 seed layer was removed by etching solutions before atomic layer deposition, and the Al2O3 residue would provide nucleation sites on the graphene surface. Benefiting from the decreased thickness of the dielectric film, the transconductance of the GFET using this method as a top-gate dielectric film deposition process shows an average 44.7% increase compared with the GFETs using the standard Al evaporation seed layer methods. [ABSTRACT FROM AUTHOR]

The Internet widely display interactions between various parties, calling for research to understand how message- and source-related factors in these easily observed interactions influence observers' attitudes in health contexts. From a masspersonal communication perspective, we investigated how reading a conversation about seeking counseling between two members of an online support group affects individuals' attitudes toward counseling-seeking behavior. In the conversation, one group member asked for advice about depressive symptoms, and in our online experiment with adults living in the United States (N = 250), we manipulated the responding source's expert status and framing of the message that recommended seeking counseling. Guided by an overarching theoretical framework–dual-process theory of supportive communication outcomes, we found a significant three-way interaction among severity of depressive symptomatology (low vs. high), message framing (gain vs. loss), and source expertise (peer vs. peer counselor vs. professional counselor). When a peer counselor provided the message, loss framing reduced self-stigma toward seeking counseling to a greater degree than gain framing and, in turn, induced more favorable attitudes toward the behavior among people with a high severity of depressive symptomatology. Those findings provide theoretical insights into the masspersonal communication approach to health promotion and inform promising communication strategies to promote counseling-seeking behavior among people with depressive symptomatology. [ABSTRACT FROM AUTHOR]

A drain-controlled current-mode deep level transient spectroscopy (I-DLTS), was developed for investigation of Semi-ON-state current collapse in AlGaN/GaN high electron mobility transistors (HEMTs). By inserting a graded AlGaN back-barrier between the GaN channel and AlGaN buffer layer, hot-electron effect induced charging of buffer traps is effectively blocked, which contributes to a remarkable suppressed current collapse in AlGaN/GaN HEMTs under Semi-ON-state stress. A broad-distributed electron trap ${E}_{\text {T1}}$ , which features an energy level depth ${E}_{\text {C}}$ - ${E}_{\text {T}}$ and apparent capture cross section ${\sigma }_{\text {T}}$ of 0.25 ± 0.05 eV and $9.0\,\, {\pm } 1.0 {\times } 10^{-18}$ cm2, was verified to locate in the AlGaN buffer layer by I-DLTS. A combination of pulsed ${I}$ - ${V}$ and I-DLTS measurements, could be an effective method for in-situ study of current collapse mechanism in AlGaN/GaN HEMTs. [ABSTRACT FROM AUTHOR]

The physical mechanism of threshold voltage (VTH) instability in AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) was identified via capacitance-mode deep-level transient spectroscopy characterization. MIS-HEMTs with low-pressure chemical vapor deposited (LPCVD) SiNx as the gate insulator feature two distinctive trap-emission transients. The initial transient corresponds to emission of states at the SiNx/AlGaN interface, and the extracted density of state exhibits an exponential decay distribution. The subsequent transient is revealed due to hybrid emission of the interface and bulk states from the LPCVD-SiNx gate insulator, which features an activation energy higher than 1.1 eV and a capture cross section that ranges between 1 × 10−11 and 1 × 10−10 cm2. The bulk states in the LPCVD-SiNx gate insulator become charged under high gate voltage overdrive, leading to severe VTH instability in GaN-based MIS-HEMTs. [ABSTRACT FROM AUTHOR]

Different from the state of large-scale energy use and concentrated energy conservation in urban areas, the state of energy use and energy conservation in rural areas has its own characteristics and typical problems. Rural areas have been concentrated on the multiple differences in economic, social, and construction characteristics such as mountain and peace dam topography, natural and artificial construction, developed and underdeveloped, rapid urban development, and relatively backward rural development. It has practical problems that need to be solved urgently, such as the "insufficient savings" in the construction of farmhouses and the "insufficient open source" of clean energy applications. The discussion will be conducted from three aspects: the planning and layout design of rural houses in Chongqing, the performance of the enclosure structure of rural houses in key seasons, and the application of renewable clean energy in rural houses. Then put forward is the energy-saving design path of Chongqing farmhouse. It aims to improve the indoor and outdoor thermal environment of farmhouses, saving heating energy consumption in winter and air-conditioning energy consumption in summer and effectively benefit users to use renewable energy such as biogas, straw, and solar energy. Finally, explore the adaptability between the design methods of farmhouses and the local characteristics of Chongqing's rural areas. In the work of Chongqing Design Going to the Countryside, we create a contemporary farmhouse case that is not only energy-saving but also has good indoor and outdoor space quality. It also provides a reference for the energy-saving design of farmhouses in Chongqing and other regions in China. [ABSTRACT FROM AUTHOR]

Online health information, as an emerging field in health communication research, has attracted close attention from researchers. To identify major determinants of why individuals seek health information online, we conducted a meta-analysis that systematically accumulates the existing research findings. To that end, by integrating three theories or models for examining information-seeking behavior, we developed a theoretical framework for the current meta-analysis that emphasizing psychosocial, instrumental, contextual, and demographic factors. By analyzing the effect sizes from 44 articles representing 54 empirical samples, we found that the quality, trustworthiness, and utility of online health information were the dominant predictors of seeking it and that instrumental factors were more important than psychological ones in determining whether individuals did so. Moreover, the development of information and communication technology, the sampling method, and the type of information sought significantly moderated pairwise relationships between determinants and seeking behavior, whereas culture did not. Herein, we discuss the theoretical implications of our findings as well as directions for future research. [ABSTRACT FROM AUTHOR]

In this paper, by drawing on the advanced experience and norms at home and abroad, the compilation and research of "intelligent technical guidelines" for Chongqing east railway station and its supporting hub area are completed. It includes "digital technology, intelligent construction," "accurate and flexible, intelligent service," and "panoramic management and control, intelligent operation, and maintenance," and has formed the whole life cycle technical framework of "intelligent construction, intelligent service, intelligent management, and operation and maintenance." [ABSTRACT FROM AUTHOR]

The article titled "Metal-Contact-Induced Transition of Electrical Transport in Monolayer MoS2: From Thermally Activated to Variable-Range Hopping" was published in Advanced Electronic Materials in 2019. The article acknowledges additional funders that were not initially listed in the manuscript. The authors apologize for any inconvenience caused, but assure that these additions do not impact the conclusions of the paper. The authors of the article are Songang Peng, Zhi Jin, Yao Yao, Ling Li, Dayong Zhang, Jingyuan Shi, Xinnan Huang, Jiebin Niu, Yanhui Zhang, and Guanghui Yu. [Extracted from the article]

A silicon nitride (SiNx) film deposited at 500 °C by plasma-enhanced atomic layer deposition (PEALD) is employed as the gate dielectric for GaN-based metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs). An interface enhancement technology featuring in situ low-damage NH3/N2 remote plasma pretreatments (RPPs) is developed prior to the SiNx gate dielectric deposition, which contributes to an improved surface morphology while remarkably suppressed interface oxides. It is revealed by constant-capacitance deep-level transient spectroscopy that both shallow and deep states at the PEALD-SiNx/III-nitride interface are reduced by about one order of magnitude by the RPP. The in situ RPP and PEALD-SiNx gate dielectric process are implemented into fabrication of enhancement-mode MIS-HEMTs on an ultrathin-barrier AlGaN/GaN heterostructure technology platform. The fabricated MIS-HEMTs deliver an improved threshold stability and maximum output current as compared with devices without the RPP. [ABSTRACT FROM AUTHOR]

To examine the nature and content of messages presented in a popular Chinese online community about intimate partner violence (IPV), this study utilized a two-step analytic approach that combined quantitative content analysis and automatic content analysis. We collected 90,040 messages from the online community's IPV group. Study 1 analyzed 8,343 randomly selected messages. The findings suggest that social support is commonly presented, while only a few messages expressed blame toward the victims. Study 2 analyzed the whole sample via machine learning technique and further showed that this online community was a space for the victims to obtain informational resources and emotional encouragement. [ABSTRACT FROM AUTHOR]

Modulating the electronic property of graphene by doping is essential for its device and circuit applications. Unfortunately, controllable p‐ and n‐type doping in top‐gated graphene field effect transistor (GFET) is reported. Here, the O3‐based atomic layer deposited Al2O3 layer as top gate dielectric is chosen. The epoxide functional group formed in the O3 process serves as effective interface trap sites. As the sweeping range of top gate voltage increases, the Dirac point position of GFET moves from positive voltage to negative voltage. The shift of the Dirac point voltage indicates the doping transition of graphene from p‐type to n‐type. The gate voltage dependent doping can be attributed to the charge exchange between graphene and interface trap sites. Furthermore, a trap‐dependent charge model is proposed to explain the transport mechanism in the doping process. This approach is promising to produce the complementary p‐ and n‐type top‐gated GFET for multiple applications. [ABSTRACT FROM AUTHOR]

As the cutoff frequency of InP HEMTs enters the terahertz band, high frequency measurement and modeling techniques in hundreds of gigahertz become urgent needs for further millimeter monolithic integrated circuits design. We proposed a new de‐embedding method linking device measurements and modeling based on full EM simulation data acquired from HFSS and advanced design system (ADS). The simulation results for passive dummy structures are well consistent with experiments, and the de‐embedding method is proved very effective for a resistive passive device with high distributed embedding surroundings in frequency range below 40 GHz. Based on these experimental facts, the EM simulations were extended up to 300 GHz and corresponding de‐embedding deviation was further investigated. Results show that the proposed de‐embedding method has very high accuracy in the whole frequency region with a maximum S‐parameters deviation of only 2.58%. However, further analysis proves that the small residual errors still significantly affect extracted small signal model parameters of InP HEMTs especially for transit time τ. Thus, further improvements on de‐embedding accuracy or careful considerations of more error functions in modeling process are necessary for obtaining physically meaningful model parameters. [ABSTRACT FROM AUTHOR]

Mental disorder is a pressing public health issue in Singapore, especially among young adults. By integrating the risk perception attitude (RPA) framework and the theory of planned behavior (TPB), this study examines psychosocial factors underlying two mental health promotion behaviors – seeking counseling and employing self-help methods – among young Singaporeans. The results of an online survey (n = 232) showed that, as predicted by RPA framework, perceived risk interacted with self-efficacy to affect behavioral intention to seek counseling. However, this interaction existed only among individuals with favorable attitudes toward counseling-seeking behavior and not among those with unfavorable attitudes. In addition, the interaction between perceived risk and self-efficacy was not significant for the intention to perform self-help methods. The current findings demonstrated that the nature of focal behavior and attitudes are boundary conditions of the interaction effect between perceived risk and efficacy, which is the core premise of the RPA framework. These findings offer practical implications for developing campaign strategies to promote mental well-being among young adults in Singapore. [ABSTRACT FROM AUTHOR]

The physical mechanism for recovery of 2D electron gas (2DEG) in down-scaled AlGaN/GaN heterostructures with SiNx layers grown by low-pressure chemical vapor deposition (LPCVD) was investigated by means of Hall-effect characterization, scanning Kelvin probe microscopy (SKPM), and self-consistent Poisson–Schrödinger calculations. Observations using SKPM show that the surface potential of the AlGaN/GaN heterostructure remained nearly unchanged (∼1.08 eV) as the thickness of the AlGaN barrier was reduced from 18.5 to 5.5 nm and likely originated from the surface pinning effect. This led to a significant depletion of 2DEG from 9.60 × 1012 to 1.53 × 1012 cm−2, as determined by Hall measurements, toward a normally OFF 2DEG channel. Based on a consistent solution of the Schrödinger–Poisson equations and analytical simulations, approximately 3.50 × 1013 cm−2 of positive fixed charges were confirmed to be induced by a 20-nm LPCVD-SiNx passivation over the AlGaN/GaN heterostructures. The interface charge exerted a strong modulation of band bending in the down-scaled AlGaN/GaN heterostructure, contributing to the efficient recovery of 2DEG charge density (∼1.63 × 1013 cm−2). E-mode ultrathin-barrier AlGaN/GaN metal–insulator–semiconductor high-electron-mobility transistors with a low ON-resistance (RON), high ON/OFF current ratio, and steep subthreshold slope were implemented using LPCVD-SiNx passivation. [ABSTRACT FROM AUTHOR]