For sequentially monitoring and controlling average and variability of an online manufacturing process, x¯ and s control charts are widely utilized tools, whose constructions require the data to be real (precise) numbers. However, many quality characteristics in practice, such as surface roughness of optical lenses, have been long recorded as fuzzy data, in which the traditional x¯ and s charts have manifested some inaccessibility. Therefore, for well accommodating this fuzzy-data domain, this paper integrates fuzzy set theories to establish the fuzzy charts under a general variable-sample-size condition. First, the resolution-identity principle is exerted to erect the sample-statistics’ and control-limits’ fuzzy numbers (SSFNs and CLFNs), where the sample fuzzy data are unified and aggregated through statistical and nonlinear-programming manipulations. Then, the fuzzy-number ranking approach based on left and right integral index is brought to differentiate magnitude of fuzzy numbers and compare SSFNs and CLFNs pairwise. Thirdly, the fuzzy-logic alike reasoning is enacted to categorize process conditions with intermittent classifications between in control and out of control. Finally, a realistic example to control surface roughness on the turning process in producing optical lenses is illustrated to demonstrate their data-adaptability and human-acceptance of those integrated methodologies under fuzzy-data environments.

The current situation in Vietnam is that patients with their illness can easily go to drugstores to buy medicine by their own prescriptions or drugstore ones. This exists for a long time. This research is not focus on the ways to combat this phenomenon, but we aim to study the factors that are affecting behaviors of patients in choosing drugstores in the South of Vietnam. We employed both quantitative and qualitative methodologies for this research; 400 people responded to survey questions and 10 people involved in interviews. Briefly analysis from quantitative study showed that the affected factors are price and process, which is convenient, and people answered to interview agreed that price and product are the important factors for them to go to drugstores. Hence, the sales and policies makers should pay attention to the needs of customers in doing business of drugstores.

Vietnam in recently years is considered to be a country with rapid development of the e-commerce with a lot of online shopping sites e.g., Shoppee, Lazada, Tiki, and Adayroi. These sites provide a high variety of products from household devices to motorbike. However, Vietnamese people are still aware of risk in doing e-purchasing. They often go to tradition outlets to buy products. This study aims to investigate the antecedents of customers’ intentions for the case of using Internet as a new way to purchase products in Vietnam. A research model is developed relied on the integration of theory of Technology Accepted Model and Perceived risk theory to predict customer intentions to online shopping. Five factors are included in this research: Perceived Usefulness, Perceived Ease of use, Perceived Risk, Customer’s Attitude and Customer’s intention. A convenience sample of 336 respondents was collected through online and offline survey. The results of this study support that exist a positive relationship between Perceived ease of use and Perceived usefulness. Attitude, in turn is positive affected by Perceived ease of use and Perceived usefulness in which Perceived ease of use has stronger influences. While perceived risk negative impacts customers’ intention, perceived risk and Perceived usefulness, on the other hand, positive influences customers’ intention. All hypotheses are supported. It is evident that online shoppers intention are evaluated mostly based on their attitude, perceived usefulness, perceived ease of use and perceived risk.

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