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Background Dementia is a global public health priority. Many modifiable factors have been shown to influence the development of dementia, but these factors are not adequately known by the general public. This study assessed public awareness of the factors that are associated with dementia among the general population in China. Methods A cross-sectional study was conducted from May to October 2019 using an Internet-based questionnaire. We collected basic sociodemographic characteristics and investigated participants’ knowledge of risk and protective factors that are associated with dementia. The primary outcome measures were the proportions of participants who identified each option as a risk or protective factor. Logistic regression analysis was performed to compare levels of the knowledge of factors that are associated with dementia across populations with different demographic characteristics. Results Data from a total of 3,338 respondents were analyzed. The percentages of participants who accurately identified dementia risk factors were the following: 84.24% for negative affect, 65.07% for alcohol use, 56.68% for smoking, 48.74% for hypertension, and 42.66% for diabetes. The percentages of participants who accurately identified dementia protective factors were the following: 90.00% for exercise, 84.69% for social activity, 80.92% for intelligence games, 74.45% for reading, and 6.14% for antihypertensive or hypolipidemic drugs. The majority of Chinese people correctly recognized the role of lifestyle factors in the development of dementia but not medical factors. Levels of knowledge of the factors that are associated with dementia were significantly distinct across populations with different characteristics. The following sociodemographic characteristics were associated with more comprehensive knowledge of dementia risk and protective factors: women, young age, high education levels, white-collar jobs, and contact with individuals with dementia. Conclusions Public awareness and knowledge of risk and protective factors for dementia in China are still insufficient. More efforts are needed to publicize information about dementia to reduce risk and prevent dementia.

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Microgrids (MGs) are composed of multiple distributed generators (DGs) interfaced to micronetwork through paralleled connected power inverters (PIs). Load sharing among multiple DG units is an important task for autonomous operation of microgrids. In order to realize satisfactory power sharing and voltage regulation between DG units, different voltage droop control strategies have been reported in the literature. In the medium voltage (MV) microgrids, power sharing, and voltage regulation often deteriorate due to dependence on nontrivial feeder impedances. The conventional control strategies are subject to steady-state active and reactive power-sharing errors along with system voltage and frequency deviations. Furthermore, complex microgrid configurations either in looped or meshed networks often make power balancing and voltage regulations more challenging. This paper presents an improved control strategy that can be extended for radial networks in order to enhance the accuracy of power sharing and voltage regulation. The proposed control strategy considers load voltage magnitude regulation as opposed the voltage regulation at inverters terminals. At the same time, a supervisory control loop is added to observe and correct system frequency deviations. This proposed method is aimed at replacing paralleled inverter control methods hitherto used. Simulation studies of the proposed scheme in comparison with the conventional control strategy in MATLAB/Simulink validate the effectiveness of the proposed strategy.Inventions 2018, 3, 47 2 of 14 mode, the distributed power inverters interfaces (DPIs) between load and microsource are governed by the droop control algorithm, which are responsible for the voltage regulation and power sharing in accordance with their ratings and corresponding energy source power. Hence, the control of paralleled connected power inverters has been investigated in recent years [11][12][13].Conventionally, the frequency and voltage magnitude droop are used as decentralized control schemes among DG units [11,12]. It can be seen as primary control of a synchronous machine. With the help of droop control active power sharing can be achieved among these DGs units. However, reactive power sharing is highly dependent on a DG unit's output filter and feeder impedances [11,[14][15][16]. The identical feeder impedance could be unequal as various DG units and load are located at different distances to each other. The unequal LCL-filter's impedance among various DGs units are due to different design considerations and system conditions [15]. In addition, configuration of microgrid network and existence of local loads often aggravate the power balancing problem. Therefore, power sharing of conventional droop control can be affected by mismatch of feeder impedances and make islanded microgrids less flexible and reliable [11,15].To solve the power control issue, a considerable number of control schemes based on droop concept have been proposed, which are classified into four main categories: (1) virtual fram...