Sentiment Analysis of Customer Feedback in Online Food Ordering Services

Background: E-commerce websites have been established expressly as useful online communication platforms, which is rather significant. Through them, users can easily perform online transactions such as shopping or ordering food and sharing their experiences or feedback. Objectives: Customers\u27 views and sentiments are also analyzed by businesses to assess consumer behavior or a point of view on certain products or services. Methods/Approach: This research proposes a method to extract customers\u27 opinions and analyse sentiment based on a collected dataset, including 236,867 online Vietnamese reviews published from 2011 to 2020 on foody.vn and diadiemanuong.com. Then, machine learning models were applied and assessed to choose the optimal model. Results: The proposed approach has an accuracy of up to 91.5 percent, according to experimental study findings. Conclusions: The research results can help enterprise managers and service providers get insight into customers\u27 satisfaction with their products or services and understand their feelings so that they can make adjustments and correct business decisions. It also helps food e-commerce managers ensure a better e-commerce service design and delivery

Air Emission Inventory

Emission inventory (EI) is a comprehensive listing of pollutants from all sources in a geo-graphical area during a period of time. The development of EI database is very important to air quality management and helps us to find out main sources. In general, to develop a reliable EI for one specific area, the following steps are involved: (i) list the types of sources, (ii) determine the types of air pollutant emission from each of the listed sources, (iii) find out the emission factor (EF) for each of the concerned pollutants, (iv) determine the number and size of specific sources in the area, and (v) multiply the appropriate numbers from step (iii) and (iv) to obtain the total emissions and then sum up the similar emissions to obtain the total for the area. With emission inventory, we can define the main sources in the study area and have the best solution for clean air action. Besides, the result from EIs can be used to study in other sectors related to human health, economic loss from air pollution, etc. This chapter will describe the method for development of an air emission inventory for developing and developed countries

Optimal Methodology to Generate Road Traffic Emissions for Air Quality Modeling:Application to Ho Chi Minh City

Growing population, consuming a large amount of energy such as combustion of fossil fuel, increasing pollutant emissions in the atmosphere are the threats to the sustainable development of our planet in general, and of the air quality in particular. According to the World Health Organization, air pollution causes the death of more than 2 million people per year in developing countries, and millions of people also suffer from various respiratory illnesses. Road traffic is the main source of air pollution in cities and there are large uncertainties associated to this source of pollution. Different models are available to quantify the amount of pollutants released by road traffic. However, these models always require a large amount of information and work, and thus their use results expensive. These limitations are difficult for the study and the management of air quality in cities from the developing world. Thus, it is extremely difficult to design efficient abatement strategies to reduce air pollution. For this reason, it is necessary to develop a new methodology for generating road traffic emissions to contribute to a better management of the urban air quality. The first aim of this PhD thesis is to develop and to validate a new model for generating road traffic emissions in several steps with different levels of complexity. The developed model is called EMISENS. Its main specifications are: (i) EMISENS is able to compute a total amount of emissions and to distribute it in time and in space using a methodology which combines the top-down and the bottom-up approaches; (ii) the model is able to compute the emissions and the uncertainties within a reasonable computing time and (iii) the model formulation is based on well referenced methodology (COPERT IV). The validation of EMISENS model was carried out by its application over Strasbourg, France. The results of EMISENS have been compared with the results of the more complete and complex model Circul'air which is currently used to manage the Strasbourg air quality. After comparing the results of the two models, it appeared that they are very close. This example of application illustrates the capacity of EMISENS to calculate road traffic emission inventory (EI) for cities in developed countries as well as in developing countries. Further on, a complete EI is carried out over Ho Chi Minh City (HCMC) by applying an innovative methodology based on the application of the EMISENS model. HCMC is the largest city in Vietnam, it had more than 6 million inhabitants in 2006. It has more than three million vehicles and 28,500 factories in the city. High levels of air pollution are thus very often detected. The purpose of this part of the research consists in applying the EMISENS model to generate road traffic emissions. For the other emission sources, the top-down approach is used for generating the EI. The results show that the road traffic is the main emission source in the city. The motorcycles are responsible of the traffic emissions (94 % of CO, 68% of Non-Methane Volatile Organic Compound (NMVOC), 61 % of SO2 and 99 % of CH4). Two scenarios for reducing traffic emissions are evaluated to reduce the HCMC emissions for the year 2015 and 2020. In addition, two other scenarios are the Business as Usual scenarios for the year 2015 and 2020 are also studied to evaluate the traffic emissions in HCMC. The third part of this work consists in applying air quality models to the region of HCMC, the aim here is to study abatement strategies for emission reduction in the city. The results of the simulation show that the plume of O3 is developed in the north-western part of the city. These results are in good agreement with the measurements. Among the four previous emission scenarios, we chose only two reduction emission scenarios to study the effective abatement strategies for the year 2015 and 2020 in using air quality model. These two affective abatement strategies are adopted to help the local government to take decision for managing air quality in HCMC. The 100 Monte Carlo (MC) simulations are run for estimating the uncertainty in the results of air quality simulations. The results of these two abatement strategies showed that if the local government follows the emission control plan: For 2015, the O3 concentration in 2015 will be similar to the present O3 concentration. For 2020, the O3 concentration in 2020 will decrease of around 10% to 30% of O3 in comparison to the actual level. However, the O3 concentration in 2020 is still higher than standard limit. The developed methodology for generating road traffic emissions offers several advantages. It is able to calculate a road traffic emission for both developing and developed countries. The calculation is divided in several steps with different level of complexity. Therefore, this methodology provides the new approach to manage air quality in cities

Nearly isotropic upper critical fields in a SrFe1.85_{1.85}Co0.15_{0.15}As2_{2} single crystal

We study temperature dependent upper critical field $H_{\rm c2}$ of a SrFe$_{1.85}$Co$_{0.15}$As$_{2}$ single crystal (\textit{T$_c$}=20.2 K) along \textit{ab}-plane and \textit{c}-axis through resistivity measurements up to 50 T. For the both crystalline directions, $H_{\rm c2}$ becomes nearly isotropic at zero temperature limit, reaching $\sim$ 48 T. The temperature dependence of the $H_{\rm c2}$ curves is explained by interplay between orbital and Pauli limiting behaviors combined with the two band effects.Comment: Proceedings of M2S-IX, Tokyo 200

A Case Study of Characteristics of Damages Caused by Typhoon EWINIAR 2006 in South Korea

During recent years, the climate of Korea has clearly been divided between dry season and rainy season due to the global warming and other reasons, and a record breaking rain is falling every year. The mountain slopes in Korea receives significant damage generally during the seasons of high rain front and typhoon. In 2006, the rainy season started in July and Typhoon EWINIAR which hit South Korea between July 26 and 28 caused significant damage to various slopes and roads. This paper presents a case study of the damages and characteristics of the damages to cut slopes, fill slopes, and roads caused by the concentrated heavy rains for 3 days in the regions of Inje and YangYang

C-reactive Protein Positively Correlates With Metabolic Syndrome in Kidney Transplantation Patients

ObjectiveC-reactive protein (CRP) is an independent risk factor for renal allograft loss and predicts all-cause mortality in kidney transplantation patients. Metabolic syndrome has also been associated with increased mortality in kidney transplantation patients. The aim of this study was to investigate the relationship between CRP and metabolic syndrome in kidney transplantation patients.Materials and MethodsFasting blood samples were obtained from 55 kidney transplantation patients. Metabolic syndrome and its components were defined using diagnostic criteria from the International Diabetes Federation.ResultsIn total, 13 kidney transplantation patients (23.6%) had metabolic syndrome. Fasting CRP levels positively correlated with metabolic syndrome (p = 0.001). Univariate linear regression analysis indicated that fasting serum CRP values were positively correlated with body weight (p = 0.001), waist circumference (p = 0.008), body mass index (p < 0.001), and body fat mass (p = 0.042). Multivariate forward stepwise linear regression analysis of the significant variables showed that body mass index (β = 0.455, R2 = 0.207, p < 0.001) was an independent predictor of serum CRP levels in kidney transplantation patients.ConclusionCRP level positively correlated with metabolic syndrome in kidney transplantation patients. Body mass index was an independent predictor of serum CRP levels in kidney transplantation patients

High power, ultra-broadband supercontinuum source based on highly GeO2 doped silica fiber

We demonstrate a 74 mol % GeO2 doped fiber for mid-infrared supercontinuum generation. Experiments ensure a highest output power for a broadest spectrum from 700nm to 3200nm from this fiber, while being pumped by a broadband 4 stage Erbium fiber based MOPA. The effect of repetition rate of pump source and length of Germania-doped fiber has also been investigated. Further, Germania doped fiber has been pumped by conventional Silica based photonic crystal fiber supercontinuum source. At low power, a considerable broadening of 200-300nm was observed. Further broadening of spectrum was limited due to limited power of pump source. Our investigations reveal the unexploited potential of Germania doped fiber for mid-infrared supercontinuum generation. This measurement ensures a possibility of Germania based photonic crystal fiber or a step-index fiber supercontinuum source for high power ultra-broad band emission being pumped a 1060nm or a 1550nm laser source. To the best of our knowledge, this is the record power, ultra-broadband, and all-fiberized SC light source based on Silica and Germania fiber ever demonstrated to the date