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With the hospitality industry facing an ongoing labor shortage exacerbated by the pandemic, this study extends research on job applicants' preferences for job offers, drawing primarily from the person-environment fit theory. It focuses on understanding the importance of entry-level salary, person-job (PJ) fit, and person-organization (PO) fit within the context of hospitality businesses. Using a two-phase model that unifies and extends the job choice of single-attribute and multiple-attribute job offers, this study uses mixed ANOVA analyses to test the proposed hypotheses. Our main result shows that job applicants experiencing high perceived financial stress are more likely to accept the job offer with both PJ fit and PO fit when compared to (a) the job offer with a higher entry-level salary and PJ fit and (b) the job offer with a higher entry-level salary and PO fit. Based on these findings, several theoretical and empirical implications are discussed. • Job choice is complex as applicants have distinct preferences involving a series of tradeoffs between multiple offers. • Financial stress plays a significant role in determining job choices. • Person-job fit may be the most preferred by hospitality job applicants. • Salary alone may not be sufficient to sway job applicants. [ABSTRACT FROM AUTHOR]

In the building sector, remodeling of existing buildings that have low energy efficiency is a required strategy to achieve carbon neutrality. To establish a cost-effective remodeling strategy for existing buildings, accurate measurement of the thermal insulation performance of existing building envelopes is necessary. In general, to evaluate the insulation performance of a building envelope, the U-value is calculated based on the heat flux measured using a heat flow meter, which is an expensive physical sensor. This study developed an in-situ virtual heat flow meter (vHFM) model that can replace existing heat flow meter sensors. The in-situ vHFM model satisfied ASHRAE Guideline 14 with an R 2 of 0.989, coefficient of variation root mean square error of 15.24%, and normalized mean bias error of −0.06% compared to the data measured using a traditional sensor. In addition, the validation through two case studies demonstrated that the field applicability of the in-situ vHFM model was very high. • An in-situ virtual heat flow meter (vHFM) model was developed and validated. • The in-situ vHFM model can accurately predict the heat flux in existing building walls using indoor air temperature, outdoor air temperature, indoor wall surface temperature, and temperature difference between indoor and outdoor air. • An artificial neural network (ANN) model performed best of four regression models. • The ANN-based in-situ vHFM model satisfied ASHRAE Guideline 14. • The developed in-situ vHFM model was evaluated using two case studies. [ABSTRACT FROM AUTHOR]

This study assessed the energy-saving and climate-adaptive potential of cool skin and ventilated cavity skin facade technologies in Seoul's high-rise apartment buildings. We created weather scenarios for historical, mid-term future, and long-term future conditions using Coordinated Regional Downscaling EXperiment (CORDEX) method. Building energy simulations were conducted on a South Korean high-rise apartment model to evaluate their performance under different weather conditions. The results indicate that cool skin and ventilated cavity skin technologies can save cooling energy during summers but lead to heating energy penalties in winters. Ventilated cavity skin outperforms cool skin, offering better cooling energy savings and reduced heating penalties. Combining both technologies yields the highest overall energy savings, with 7 %, 9 %, and 10 % cooling energy savings for cool skin, ventilated cavity skin, and the combined package, respectively. However, cool skin increases heating energy consumption by 5 %, while ventilated cavity skin has minimal impact on heating energy. These envelope technologies also reduce peak electricity demand by at least 5 %, 8 %, and 9 %, respectively. They contribute to heat stress reduction, enhance resilience, and decrease extreme heat risks for occupants during power outages by at least 18 % under various weather conditions. Considering the prevalence of aging high-rise apartments in South Korea, adopting these envelope renovation strategies can effectively reduce cooling loads, enhance thermal comfort, and boost resilience under future climates, while avoiding costly reconstruction. • Cool skin and ventilated cavity skin strategies significantly reduce annual energy consumption and improve occcupants' thermal resilience. • Ventilated cavity demonstrates great cooling energy savings and minimal heating energy penalties. • Cool skin and ventilated cavity skin strategies mitigate occupant risks and discomfort during heatwave events. • Ventilated cavity skin materials can be tailored to maximize energy savings depending on regional climate conditions. [ABSTRACT FROM AUTHOR]

Commercial alpha-emitting sources are fabricated mainly in a disc type. An alpha particle irradiator in Radiation Bioengineering Laboratory at Seoul National University was installed with an Am-241 disc source. Commercial Am-241 disc sources are fabricated by incorporating the radioactive element into a thin substrate layer. Those disc sources are utilized assuming that the radioactive element is uniformly distributed in the active layer of disc sources. In this study, we employed peeled-off Gafchromic EBT3 films to investigate the uniformity of areal radioactivity density over the disc source and to measure the effect of non-uniform activity distribution on dose distribution at the bottom of the cell culture dish positioned in a varying distance from the source. The measurements with the peeled-off EBT3 films informed that the areal activity density in the disc source differed by up to approximately 45% from the average. However, the inhomogeneous Am-241 distribution in a disc source did not affect the radial distribution of fluence rate at the inner bottom of cell dish when the dish is apart from the source sufficiently. The dose distribution measured with an EBT3 film nearly accorded with that obtained by Monte Carlo simulation assuming the uniform Am-241 activity distribution in the active layer of the disc source. Finally, the dose to a single-cell layer of 5 μm in a nominal thickness was obtained by Monte Carlo simulation assuming a uniform Am-241 activity distribution in the disc source at distances of 20 and 30 mm from the source. The cellular dose estimates were higher than the film dose estimates at all radial distances. The cellular dose decreased with an increasing radial distance from the center to a smaller extent than the EBT3 film dose did. [ABSTRACT FROM AUTHOR]

Heat pump testing facility is used to investigate the performance and reliability of a heat pump unit. During the testing period, energy is utilized by the facility mainly through cooling with a refrigeration unit and heating with an electric heater to control and maintain the test conditions of the heat pump unit. However, research study on the energy consumption analysis of the heat pump test facility is rarely found in literature. In this study, the performance characteristics of the testing facility for a water-to-water heat pump are investigated according to the variation of heat pump capacity and COP in both cooling and heating operating modes. The objective is to analyze the energy consumption of the test facility used to investigate the performance of a water-to-water heat pump unit. The analysis of experimental test results showed that the total energy consumption rate of the heat pump test facility increased as capacity and COP of heat pump increased in both cooling and heating modes. However, the increment according to COP variation was smaller than capacity variation. Also, the total energy consumption rate of the testing facility was about ten times more than the energy consumption rate of the heat pump unit. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop an Artificial Neural Network (ANN) model that can predict the amount of cooling energy consumption for the different settings of the variable refrigerant flow (VRF) cooling system's control variables. Matrix laboratory (MATLAB) and its neural network toolbox were used for the ANN model development and test performance. For the model training and performance evaluation, data sets were collected through the field measurement. Four steps were conducted in the development process: initial model development, input variable selection, model optimization, and performance evaluation. In the initial model development and input variable selection process, seven input variables were selected as input neurons: TEMP OUT , HUMID OUT , TEMP IN , LOAD COOL , TEMP SA , TEMP COND , and PRES COND . In addition, the initial model was optimized to have 2 hidden layers, 15 hidden neurons in each hidden layer, a learning rate of 0.3, and a momentum of 0.3. The optimized model demonstrated its prediction accuracy within the recommended level, thus proved its potential for application in the control algorithm for creating a comfortable indoor thermal environment in an energy-efficient manner. [ABSTRACT FROM AUTHOR]

Background: Warfarin has a narrow therapeutic window. We hypothesized that genetic factors related to warfarin metabolism (CYP2C9) and activity (VKORC1) would show stronger associations than modifiable factors with the quality of anticoagulation control and risks for thromboembolism and hemorrhage.Methods: In this retrospective cohort analysis, clinical and genetic data were collected from 380 patients with atrial fibrillation (AF) who were followed for an average observation period of 4 years. We evaluated the factors associated with time in therapeutic range (TTR, international normalized ratio [INR]: 2-3) and vascular events (either thromboembolic or hemorrhagic), including both genetic (CYP2C9 and VKORC1 genotype) and modifiable factors (anticoagulation service and warfarin dose assessment interval).Results: The genotypic frequency of CYP2C9*3 (rs1057910) was 9.5% and that of VKORC1 1173C>T (rs9934438) was 16.3%. TTR showed dependence on VKORC1 polymorphism: TTR was higher in carriers of the VKORC1 1173C>T than of the VKORC1 TT genotype (61.7 ± 16.0% versus 56.7 ± 17.4%, P = .031). Multivariate testing showed that the VKORC1 genotype and anticoagulation service were independently related to labile INRs (TTR <65%). Vascular events were observed in 66 patients (18.4%) during the study period. A Cox proportional hazard model showed that the use of anticoagulation service and patients' characteristics, such as AF-thromboembolic risk (CHA2DS2-VASc score: Congestive heart failure, Hypertension, Age 75 years or older, Diabetes mellitus, previous Stroke or transient ischemic attack, Vascular disease, Age 65 to 74 years, female) and consequence (neurologic disability), but not genetic factors, were independently associated with vascular events.Conclusions: Both genetic factor (VKORC1 genotype) and clinical efforts (anticoagulation service) influenced the quality of anticoagulation control. However, clinical events were more strongly associated with patient characteristics and clinical efforts than with genetic factors. [ABSTRACT FROM AUTHOR]

Crack tip stress and displacement fields for a propagating crack at constant velocity along a gradient in orthotropic functionally graded materials (OFGMs) with an exponential variation of the shear modulus and density are developed. The crack tip fields are obtained by using wave potentials and the Airy stress function through an asymptotic analysis. Solutions are obtained for orthotropic characteristics of two kinds. Using the stress fields, the effects of material nonhomogeneity on the stress components are investigated. In addition, contours of the constant maximum shear stress at a propagating crack tip are generated and the effects of material nonhomogeneity on the isochromatics are discussed. [ABSTRACT FROM AUTHOR]

This study focuses on the occupational well-being process in the formation of hotel employees’ subjective well-being based on the recovery experience scale (RES). More specifically, the study (1) evaluates the construct validity of the RES in the hotel sector and (2) examines structural relationships between the RES, organization-based self-esteem (OBSE), job dedication (JOD), career satisfaction (CAS), and life satisfaction (LIS) in a heuristic model. To test the hypotheses, a total of 376 hotel employees were considered in an empirical analysis using a two-step SEM approach. The results verify sufficient validity for the four RES factors and reveal that all recovery experiences, namely psychological detachment, relaxation, mastery experiences, and control, predicted OBSE. In addition, OBSE had positive effects on JOD, CAS, and LIS, and JOD and CAS had significant positive effects on LIS. These results have important implications, and the study's limitations provide some interesting avenues for future research. [ABSTRACT FROM AUTHOR]

The effect of nitrogen doping in Ge–In–Ga–O (GIGO) semiconductors was investigated via thin film characterization and the evaluation of the associated thin film transistor (TFT) properties. As the nitrogen content [N 2 /(Ar + O 2 + N 2 )] increases from 0% to 40% during the sputter deposition, the threshold voltage ( V th ) of the corresponding TFT devices shifts toward positive values (from −1.88 to 3.08 V) and the subthreshold swing decreases (from 0.40 to 0.18 V/decade) accordingly, while the amount of V th shift (Δ V th ) by hysteresis is suppressed (from 1.33 to 0.22 V). In particular, the device stability under negative gate bias (−20 V) stress for 3 h improves considerably with total threshold voltage shift (Δ V th ) values of −6.25 V and −0.69 V. As the amount of nitrogen incorporated in the semiconductor increase, the device μ FE decreases significantly (from 19.3 to 5.76 cm 2 /V s). Temperature dependent analyses suggest that Coulombic scattering of the carriers near the nitrogen species is the major mechanism of such mobility degradation. [ABSTRACT FROM AUTHOR]

This study proposes a comprehensive hybrid model of the use of online travel communities for social and emotional loneliness (OTS-SEL), identification with the peer group (IPG), peer communication (PCO), user satisfaction (USAT), and behavioral intentions to follow travel advice (INFTA). The study determines whether OTS-SEL is composed of three subdimensions of social loneliness, friend loneliness, and romantic loneliness based on a second-order stricture; tests a structural equation model to examine the relationships between OTS-SEL, IPG, PCO, USAT, and INFTA; and provides a multi-group analysis to investigate the moderating effect of emotional expressivity (EME) on the relationship between USAT and INFTA. The results provide support for all hypotheses except for the one about the relationship between IPG and USAT; have important implications; and offer interesting avenues for future research. [ABSTRACT FROM AUTHOR]

In this paper, breaking wave impact forces on vertical and inclined piles are studied by using a 3D numerical model. A method for obtaining net breaking wave impact forces from the measured response time history is also investigated. The computed forces are compared with the results of hydraulic model tests. However, because the piles installed in the numerical model are modeled as rigid objects, it is not possible to make a direct comparison between the CFD (Computational Fluid Dynamic) results and the experimental data. A force separation procedure is used for the experimental data. A low pass filter and EMD (Empirical Mode Decomposition) are employed for removing the effect of dynamic amplification in the experimental data, and the filtered results are compared with the numerical results. Based on the results, DAFs (Dynamic Amplification Factor) are estimated for these particular structures. Moreover, Duhamel integral is used to reproduce dynamic breaking wave forces (i.e., net breaking wave force+the force which is the amplified component due to the structure׳s vibration) based on the breaking wave forces calculated by the CFD model. The reproduced results are compared with the unfiltered experimental data for the verification of the method stated above. [ABSTRACT FROM AUTHOR]

Abstract: The device performance and bias stability of radio frequency (RF) sputtered Ge-doped InGaO (GIGO) thin film transistors (TFTs) were investigated as a function of oxygen partial pressure during the deposition step. At low oxygen partial pressure, the electrical performance and stability of GIGO TFTs were significantly improved with a decrease of oxygen deficient bonding states, suggesting strong oxygen bonding ability of Ge atoms. We demonstrate that these changes can be corroborated with the evolution of the electronic structure, such as band alignment and band edge states below the conduction band, as measured by X-ray photoelectron spectroscopy and spectroscopic ellipsometry analysis. As the oxygen partial pressure decreased, the energy difference between the conduction band minimum and Fermi level and the deep band edge states was decreased. In particular, it was revealed that, with an increase of oxygen partial pressure, the relative energy level of the band edge states was shifted to a deeper level within the bandgap. [Copyright &y& Elsevier]

Objective: To determine the impact of contralateral carotid occlusion (CCO) and/or vertebral artery occlusion (VAO) on the development of early postoperative neurologic complications after carotid endarterectomy (CEA) or carotid artery stenting (CAS). Methods: A retrospective analysis was conducted using a database of patients who underwent CEA (n = 698) or CAS (n = 455) at a single institution. Excluded were 44 CEAs synchronously performed with coronary artery bypass grafting and 76 CASs performed without an embolic protective device (n = 69) or that resulted in technical failures (n = 7). All CEAs were the conventional type and performed under general anesthesia, and carotid shunts were routinely used. Patients were categorized into three groups according to patency of the contralateral carotid and vertebral arteries: Group I (no CCO or VAO); Group II (CCO with or without VAO); Group III (with VAO but no CCO). CCO or VAO were diagnosed with two or more carotid imaging studies including duplex ultrasonography, computed tomography angiography, magnetic resonance angiography, or conventional carotid angiography. Patient groups were compared with demographics, preoperative symptomatic status, and frequencies of early (<30 days) symptomatic neurologic complications (ESNCs) including transient ischemic attack and stroke. Postprocedural stroke alone was separately compared. Univariate (χ 2 or Fisher's exact test) and multivariate analysis (multiple logistic regression) were conducted to determine predictors of ESNC or postprocedural stroke. Results: ESNCs and postprocedural stroke developed significantly more often with CAS compared with CEA (ESNC, 2.6% vs 8.1%; P < .001; stroke, 1.3% vs 6.8%; P < .001). In group II, the frequency of ESNCs was higher (6.8% vs 1.8%; P = .044), but the frequency of postprocedural stroke was not significantly higher (2.3% vs 0.9%; P = .405) in the CEA group. By multivariate analysis, the presenting symptom of stroke (odds ratio, 3.612; 95% confidence interval, 1.288-10.130; P = .015) and group II (odds ratio, 7.242; 95% confidence interval, 1.727-30.374; P = .007) were independent risk factors of ESNC following CEA but not CAS. When we analyzed the risk factor for postprocedural stroke alone, the presenting symptom of stroke was the only risk factor, while presence of CCO or VAO was not. Conclusions: CAS was followed by a significantly higher frequency of ESNC and postprocedural stroke compared with CEA. By subgroup analysis, CCO was a risk factor for ESNC but not for postprocedural stroke alone in patients undergoing CEA. Unilateral or bilateral VAO was not associated with a higher rate of ESNC or stroke in CEA or CAS. [Copyright &y& Elsevier]

Abstract: The use of mechanoluminescence (ML) has enabled a new technique for the determination of the mode I stress intensity factor (SIF) in SrAl2O4:Eu2+,Dy3+ (SAO). The stress rate fields and its cumulative isostress contour patterns in terms of ML in the vicinity of a crack tip during compact tension were evaluated based on the two different stress criteria of the hydrostatic and deviator in triggering the trap-releasing processes of the ML mechanism. The magnitude and shape of the crack tip stress field predicted by the deviator stress criterion rather than by the hydrostatic stress criterion showed good agreement with the experimental ML evidence in a determination of the SIF from the ML intensity. The analysis derived from the deviator stress criteria not only allowed the possibility of characterizing the fracture toughness in a range of modes under static and dynamic crack propagation, but also provided a better understanding of the ML mechanism of the trap-releasing process in SAO. [Copyright &y& Elsevier]

Abstract: Neuromyelitis optica (NMO) is an inflammatory demyelinating disorder that predominantly affects the optic nerve and spinal cord; however, symptomatic brain involvement is not rare and is sometimes an initial manifestation in NMO. In this study, we investigated the characteristic features of patients with NMO with symptomatic brain involvement as the initial manifestation of disease (NMObrain) compared with patients with NMO who presented initially with optic neuritis or myelitis (NMOON/myelitis). We retrospectively reviewed 27 consecutive Korean patients with NMO with aquaporin-4 antibodies. Patients with NMObrain (n =9) initially presented with intractable hiccup/nausea/vomiting and/or encephalopathy at a younger age than the patients with NMOON/myelitis (n =18) (p <0.01). During the disease course, the patients with NMObrain continued to show more frequent symptomatic involvement of the brain than the 18 patients with NMOON/myelitis (p <0.05). At the final visit, the mean age was also significantly lower in patients with NMObrain than in patients with NMOON/myelitis (p <0.01); however, the Expanded Disability Status Scale scores, used to evaluate disease progression, were not different between the two groups. Our study suggests that patients with NMO who present initially with symptomatic brain involvement may have earlier disease onset and become disabled at a younger age compared to patients with typical NMO. Additional large scale prospective studies are warranted. [Copyright &y& Elsevier]

Abstract: This paper presents the potential benefits of the thermal load sharing between the two different building types such as residential house and commercial office building through the process of energy simulation modeling. Both the house and office simulation models have the same geometries with the conditioned spaces of 200 m2 each for the weather conditions of Seoul, South Korea. This study shows and analyzes the thermal energy demand and consumption results simulated from the four different scenarios using the EnergyPlus V6.0 thermal simulation program; i.e., Case-1) a house with conventional heating and cooling systems, Case-2) an office with conventional heating and cooling systems, and Case-3) a simple sum of the two cases (i.g., Case-2 + Case-3), and Case-4) a load sharing model that provides heating and cooling to both the house and the office using combined HVAC systems. This paper evaluates the thermal energy consumption patterns and potential benefits of the load sharing system compared to the conventional systems. The optimal system configurations of the load sharing systems are proposed. In conclusion, this paper discusses the potential issues and challenges for implementing the load sharing systems as well as the possible solutions for these issues. [Copyright &y& Elsevier]

Abstract: Underfloor air distribution (UFAD) systems have received increasing attention during the past decades due to potential advantages over conventional overhead (OH) forced air systems. Among design and operating parameters, air handling unit (AHU) supply air temperature (SAT) has significant impacts on the overall UFAD performance. In this study, the detailed whole-building energy simulation program, EnergyPlus version 6.0, was used to perform the analysis on the impact of SAT on the UFAD system performance such as energy, humidity and comfort under Korean climatic condition. It turns out that raising AHU SAT causes increased HVAC energy consumption due to heating and fan energy increase despite the cooling energy reduction. The increase in the heating energy was mainly due to the increased central AHU heating coil demand increase with the higher SAT. In addition, raised SAT elevated relative humidity in the room space during the summer season due to the fact that higher SAT set-point in the central AHU was not able to sufficiently dehumidify conditioned air compared to the lower SAT. However, the increased SAT reduced the number of hours when the occupants might feel cold during the heating season in the interior zone where the heating is not provided. [Copyright &y& Elsevier]

Abstract: Clothing affects people''s perception of the thermal environment. Two dynamic predictive models of clothing insulation were developed based on 6333 selected observations of the 23,475 available in ASHRAE RP-884 and RP-921 databases. The observations were used to statistically analyze the influence of 20 variables on clothing insulation. The results show that the median clothing insulation is 0.59 clo (0.50 clo (n = 3384) in summer and 0.69 clo (n = 2949) in winter). The median winter clothing insulation value is significantly smaller than the value suggested in the international standards (1.0 clo). The California data (n = 2950) shows that occupants dress equally in naturally and mechanically conditioned buildings and all the data has female and male dressing with quite similar clothing insulation levels. Clothing insulation is correlated with outdoor air (r = 0.45) and indoor operative (r = 0.3) temperatures, and relative humidity (r = 0.26). An index to predict the presence of a dress code is developed. Two multivariable linear mixed models were developed. In the first one clothing is a function of outdoor air temperature measured at 6 o''clock, and the second one adds the influence of indoor operative temperature. The models were able to predict 19 and 22% of the total variance, respectively. Climate variables explain only a small part of human clothing behavior; nonetheless, the predictive models allow more precise thermal comfort calculation, energy simulation, HVAC sizing and building operation than previous practice of keeping the clothing insulation values equal to 0.5 in the cooling season and 1 in the heating season. [Copyright &y& Elsevier]

Abstract: Windows are the only part in buildings that can directly penetrate the solar radiation into the space and thus the shading devices are needed to control the solar penetration. Among different blind types in office buildings, roll blinds are not operated efficiently and they are usually closed without any operations by occupants. Therefore, optimized control strategies of slat-type blinds are suggested in this study through two stages. In the first stage, double-sided blind was suggested by applying different reflectance between front and back sides of the slat and by fully rotating the slat when the system mode was switched between heating and cooling mode. When the double-sided was used along with the lighting dimming control, 24.6% of the energy saving could be achieved compared to the baseline case and the glare could be avoided at the same time. In the second stage, the control strategies of slat angle and up/down control logic were developed to fully remove the glare and improve the energy efficiency. As a result, 29.2% of energy saving could be achieved and at the same time the chance of glare was only 0.1%. [Copyright &y& Elsevier]