26 research outputs found
Effects of Altitude on Fire Smoke Diffusion in Semi-Lateral Smoke Exhaust Highway Tunnels
This paper aims to study the effects of altitude and the size of smoke outlet on fire smoke diffusion and discharge in semi-lateral smoke exhaust highway tunnels. At first, simulations of semi-lateral smoke exhaust highway tunnels were carried out in FDS (Fire Dynamics Simulator), then the distribution laws of temperature, CO concentration, smoke mass flow, and visibility in the tunnel under the conditions of different altitudes and smoke outlet areas were analyzed to figure out the effects of altitude and size of smoke outlet on fire smoke diffusion and discharge in the said tunnels. The results suggest that, in case of the same fire source power, the velocity of smoke diffusion increases with the altitude; for curves of different altitudes, the tunnel roof temperature features are basically the same, that is, the higher the altitude, the higher the temperature at the tunnel roof. When the fire source power is 20 MW, the smoke mass flow at the smoke outlet decreases with the increase of altitude, but the CO concentration grows with it, indicating that the smoke exhaust efficiency is higher in high-altitude areas. When the altitude reaches 4200 m and the fire source power is 20 MW, with the increase of smoke outlet area, the smoke discharge effect of the tunnel shows an upward trend, taking both the smoke discharge effect and economy into consideration; the smoke outlet should take a size of 4 x 3 m
Purchase Intention of Made-in-China Medical Devices among Malaysians: Does COO Effect Work?
Made-in-China products are getting popular around the world. Overcoming the âlow qualityâ perception or unfavorable country of origin (COO) effect is imperative not only for China marketers but also for any related business in other markets. Despite their huge popularity, understanding of market responses and perceptions towards China products remain unclear, especially in the technology-advanced healthcare sector. Based on the Theory of Reasoned Action (TRA) and COO effect, this study examined how subjective norms, self-image congruence and stereotype affected Malaysian consumersâ attitude and purchase intention of Made-in-China medical devices. 200 questionnaires in total were distributed among buyers in Malaysian public and private hospitals. A total of 178 valid responses were collected adopting purposive sampling technique. Findings indicated a significant impact of consumer attitude on purchase intention and attitude was found to be driven by subjective norms and stereotypes (warmth and competence), but not self-image congruency. The study also showed significant mediating effects of consumer attitude on the relationship between subjective norms and stereotype (competence) on purchase intention. The findings provide valuable insights to assist marketers in tapping into the Made-in-China medical device market as well as helping healthcare agencies plan and implement effective policy and marketing communication strategies
Purchase Intention of Made-in-China Medical Devices among Malaysians: Does COO Effect Work?
Made-in-China products are getting popular around the world. Overcoming the âlow qualityâ perception or unfavorable country of origin (COO) effect is imperative not only for China marketers but also for any related business in other markets. Despite their huge popularity, understanding of market responses and perceptions towards China products remain unclear, especially in the technology-advanced healthcare sector. Based on the Theory of Reasoned Action (TRA) and COO effect, this study examined how subjective norms, self-image congruence and stereotype affected Malaysian consumersâ attitude and purchase intention of Made-in-China medical devices. 200 questionnaires in total were distributed among buyers in Malaysian public and private hospitals. A total of 178 valid responses were collected adopting purposive sampling technique. Findings indicated a significant impact of consumer attitude on purchase intention and attitude was found to be driven by subjective norms and stereotypes (warmth and competence), but not self-image congruency. The study also showed significant mediating effects of consumer attitude on the relationship between subjective norms and stereotype (competence) on purchase intention. The findings provide valuable insights to assist marketers in tapping into the Made-in-China medical device market as well as helping healthcare agencies plan and implement effective policy and marketing communication strategies.
How the social media impact womenâs psychological well-being in the patriarchal structure? The moderating effect of social capital
Abstract Background Despite technological, political and economic progress, Pakistan is still a traditionally patriarchal society, and cultural norms curb womenâs freedom of socialization, which contributes to poor mental health. The digital technology spaces are rampant with male dominance, and offline cultural behaviours are replicated. Therefore, the current research in Pakistan intends to focus solely on women, their social media uses and the consequent impact on their psychological well-being. Furthermore, the mediation role of social capital is explored, which is linked to womenâs socialization. In virtual communication, women can expand their connection or remain limited to known people. Methods An online survey collected 240 responses from women social media users. The questionnaire was divided into demographics, social media use patterns like access, online time, frequency of use, social media uses, online social capital and psychological well-being. The obtained responses were statistically analyzed using Smart PLS. Results Pakistani women use social media extensively; however, their uses are culturally influenced. The women use social media and socialize online but do not openly disclose their personalities and emotions to extend the connection. They seek information only from acquaintances and do not trust newly developed online contacts. Therefore, the mediation role of bonding social capital is significant, referring to the importance of close ties and trust in psychological well-being. Though virtual spaces provide an opportunity for bridging social capital, women use social media for socialization; however, it doesnât contribute to womenâs psychological well-being. Conclusion Despite the higher penetration of digital technologies, cultural power still rules in developing countries like Pakistan. Social media uses are gender- and culturally specific, contributing to psychological well-being and developing social capital. The results from Pakistani society recommend ensuring a secure digital experience for women to get maximum benefits from social media and enhance their psychological well-being
Performance of the Improved Priestley-Taylor Model for Simulating Evapotranspiration of Greenhouse Tomato at Different Growth Stages
Mastering crop evapotranspiration (ET) and improving the accuracy of ET simulation is critical for optimizing the irrigation schedule and saving water resources, particularly for crops cultivated in a greenhouse. Taking greenhouse-grown tomato under drip irrigation as an example, two weighing lysimeters were used to monitor ET at two seasons (2019 and 2020), whilst meteorological factors inside the greenhouse were measured using an automatic weather station. Then the path analysis approach was employed to determine the main environmental control factors of ET. On this basis, an improved Priestley-Taylor (IPT) model was developed to simulate tomato ET at different growth stages by considering the influence of environmental changes on model parameters (e.g., leaf senescence coefficient, temperature constraint coefficient and soil evaporative water stress coefficient). Results showed that the average daily ET varied from 0.06 to 6.57 mm dâ1, which were ~0.98, ~2.58, ~3.70 and ~3.32 mm/d at the initial, development, middle and late stages, respectively, with the total ET over the whole growth stage of ~333.0 mm. Net solar radiation (Rn) and vapor pressure deficit (VPD) were the direct influencing factors of ET, whereas air temperature (Ta) was the limiting factor and wind speed (u2) had a little influence on ET. The order of correlation coefficients between meteorological factors and ET at two seasons was Rn > VPD > Ta > u2. The IPT model can accurately simulate ET in hourly and daily scales. The root mean square error of hourly ET at four stages changed from 0.002 to 0.08 mm hâ1 and daily ET varied from 0.54 to 0.57 mm dâ1. The IPT coefficient was close to the recommended PT coefficient (1.26) when the average Ta approaches 26 °C and LAI approaches 2.5 cm2 cmâ2 in greenhouse conditions. Our results can provide a theoretical basis for further optimization of greenhouse crop irrigation schedules and improvement of water use efficiency
Established and nascent entrepreneurs: comparing the mental health, self-care behaviours and wellbeing in Singapore
Mental health problems currently affect a quarter of the world's population. Recent research in western societies has started to examine the relationship between entrepreneurship and mental health problems such as Attention Deficit Hyperactivity Disorder (ADHD) and dyslexia. However, little has been done to categorize entrepreneurs into different types and investigate how their levels of mental health and well-being correspond to these types. This study divided entrepreneurs into established and nascent categories and examined this topic in Singapore. By distributing two sets of surveys, a total of 834 responses were collected, with 346 responses from established entrepreneurs and 488 responses from nascent ones. The results showed that the nascent entrepreneurs' levels of well-being were found to be much lower than those of the established entrepreneurs. Furthermore, entrepreneurs with ADHD or dyslexia symptoms generally had a much lower level of life satisfaction, compared with those without. However, the self-care behaviours observed in this sample differed somewhat from observations made in western societies, which might be explained by the different cultures and habits in Singaporean society. The findings not only highlight the need for relevant organizations to support nascent entrepreneurs but serve to remind veteran entrepreneurs to practice more healthy self-care behaviours.Published versio
Effects of Altitude on Fire Smoke Diffusion in Semi-Lateral Smoke Exhaust Highway Tunnels
This paper aims to study the effects of altitude and the size of smoke outlet on fire smoke diffusion and discharge in semi-lateral smoke exhaust highway tunnels. At first, simulations of semi-lateral smoke exhaust highway tunnels were carried out in FDS (Fire Dynamics Simulator), then the distribution laws of temperature, CO concentration, smoke mass flow, and visibility in the tunnel under the conditions of different altitudes and smoke outlet areas were analyzed to figure out the effects of altitude and size of smoke outlet on fire smoke diffusion and discharge in the said tunnels. The results suggest that, in case of the same fire source power, the velocity of smoke diffusion increases with the altitude; for curves of different altitudes, the tunnel roof temperature features are basically the same, that is, the higher the altitude, the higher the temperature at the tunnel roof. When the fire source power is 20 MW, the smoke mass flow at the smoke outlet decreases with the increase of altitude, but the CO concentration grows with it, indicating that the smoke exhaust efficiency is higher in high-altitude areas. When the altitude reaches 4200 m and the fire source power is 20 MW, with the increase of smoke outlet area, the smoke discharge effect of the tunnel shows an upward trend, taking both the smoke discharge effect and economy into consideration; the smoke outlet should take a size of 4 x 3 m
Characterizing the Complete Mitochondrial Genomes of Three Bugs (Hemiptera: Heteroptera) Harming Bamboo
Herein, we report the mitochondrial genomic characteristics of three insect pests, Notobitus meleagris, Macropes harringtonae, and Homoeocerus bipunctatus, collected from bamboo plants in Guizhou Province, China. For the first time, the damaged conditions and life histories of M. harringtonae and H. bipunctatus are described in detail and digital photographs of all their life stages are provided. Simultaneously, the mitochondrial genome sequences of three bamboo pests were sequenced and analyzed. Idiocerus laurifoliae and Nilaparvata lugens were used as outgroups, and the phylogenetic trees were constructed. The mitochondrial genomes of the three bamboo pests contained 37 classical genes, including 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNAs (tRNAs), and a control region, with a total length of 16,199 bp, 15,314 bp, and 16,706 bp, respectively. The A+T values of the three bamboo pests were similar, and trnS1 was a cloverleaf structure with missing arms. The phylogenetic analyses, using the Bayesian inference (BI) and Maximum likelihood (ML), supported that N. meleagris and H. bipunctatus belonged to the Coreoidea family, whereas M. harringtonae belonged to the Lygaeoidea family with high support values. This study involves the first complete sequencing of the mitochondrial genomes of two bamboo pests. By adding these newly sequenced mitochondrial genome data and detailed descriptions of life histories, the database of bamboo pests is improved. These data also provide information for the development of bamboo pest control methods by quick identification techniques and the use of detailed photographs
Characterizing the Complete Mitochondrial Genomes of Three Bugs (Hemiptera: Heteroptera) Harming Bamboo
Herein, we report the mitochondrial genomic characteristics of three insect pests, Notobitus meleagris, Macropes harringtonae, and Homoeocerus bipunctatus, collected from bamboo plants in Guizhou Province, China. For the first time, the damaged conditions and life histories of M. harringtonae and H. bipunctatus are described in detail and digital photographs of all their life stages are provided. Simultaneously, the mitochondrial genome sequences of three bamboo pests were sequenced and analyzed. Idiocerus laurifoliae and Nilaparvata lugens were used as outgroups, and the phylogenetic trees were constructed. The mitochondrial genomes of the three bamboo pests contained 37 classical genes, including 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNAs (tRNAs), and a control region, with a total length of 16,199 bp, 15,314 bp, and 16,706 bp, respectively. The A+T values of the three bamboo pests were similar, and trnS1 was a cloverleaf structure with missing arms. The phylogenetic analyses, using the Bayesian inference (BI) and Maximum likelihood (ML), supported that N. meleagris and H. bipunctatus belonged to the Coreoidea family, whereas M. harringtonae belonged to the Lygaeoidea family with high support values. This study involves the first complete sequencing of the mitochondrial genomes of two bamboo pests. By adding these newly sequenced mitochondrial genome data and detailed descriptions of life histories, the database of bamboo pests is improved. These data also provide information for the development of bamboo pest control methods by quick identification techniques and the use of detailed photographs