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Large underground spaces are complex and huge, with problems such as fragmented data that cannot be shared, outdated management methods, and high operation and maintenance costs. The digitization of building information and the use of digital twin technology can effectively improve the efficiency of building operation and maintenance. Using information technology to build a digital-twin-based operation and maintenance management system, the huge and discrete data and equipment system information are effectively integrated and explored for application. First, we analyze the shortcomings of the traditional delivery and operation and maintenance methods and introduce the necessity of a new method of operation and maintenance management based on digital twin; then, we divide the operation and maintenance information of the construction project into four major categories of spatial information and eight major categories of equipment information and complete the coding work, and the categorized data serve as the data basis for operation and maintenance; second, we develop a digital twin operation and maintenance management platform based on the operation and maintenance data of BIM; finally, we carry out case validation for the three major constructions. Finally, case validation is carried out for three major buildings and a large underground space and the practical application shows that the operation and maintenance management system based on digital twin technology provides technical guarantee for decentralized information and system integration management and the information management quality and efficiency of the operation and maintenance process are effectively improved. Through the practice of summarizing the experience, which is worth learning, we aim to create a large underground space operation and maintenance management method to provide a reference. [ABSTRACT FROM AUTHOR]

Maintaining thermal comfort throughout an entire year is complicated because conditions vary greatly throughout the seasons. The aim of this article was to understand the influence of seasonal characteristics on the thermal comfort in classrooms and to propose a method to select suitable adaptive coefficients for different conditions. Field investigations were conducted in an educational building in Tianjin during autumn and winter. In the study, multiple environmental parameters were investigated, including air temperature, black globe temperature, relative humidity, air velocity, and the vertical temperature difference (VTD). The respondents' thermal sensations were collected via questionnaires. The respondents' thermal sensation and the influence of seasonal characteristics on thermal sensation were analyzed. The results showed that the thermal neutral temperature varied in different seasons, and the deviations between the mean thermal sensation vote (MTSV) and the predicted mean vote (PMV) showed obvious discrepancies throughout the different seasons. Furthermore, the adaptive coefficient αs for the adaptive thermal comfort prediction model (APMV) were 0.25 and 0.57 for autumn and winter, respectively. Based on the aforementioned result, a discriminant function (DFA) using the seasonal factors to select the suitable α was obtained. [ABSTRACT FROM AUTHOR]

Based on annual minimum air temperature, the minimum ground temperature, cloudiness, air pressure, wind velocity in Lianyungang City during 1971 -2010 and sounding geopotential height, wind direction, dew point and temperature at related stations, using mathematical stepwise regression method and SPSS statistical software, short-term prediction equations of daily minimum air temperature and daily minimum ground temperature at the observation station were established. According to the relationships between frost and temperature, ground temperature, based on local frost forecast standard, the short-term forecast equation was used to judge if frost occurred in Lianyungang City. Via real-time weather monitoring , accurate and fine forecast and early warning, short-term objective forecast business system of frost in Lianyungang was established for a full range of effective service. [ABSTRACT FROM AUTHOR]

Varieties of neurophysiological measures have been utilized in visual attention studies. The linear parameters like power spectrum are the most commonly used features in the existing studies. In this paper, however, nonlinear parameters including approximate entropy, sample entropy and multiscale entropy were tested. All subjects were instructed to perform tasks with three different attention levels (i.e. attention, no attention and rest) in two experiments. Nonlinear features were extracted from the EEG signals. Then, statistical analyses and classification with support vector machine (SVM) were performed. A comparison between the classification results based on the linear feature / and the sample entropy was performed for further analysis. The results suggest that sample entropy stands out in the dynamical parameters with the accuracies of 76.19% and 85.24% in recognition of three levels of attention for the two experiments respectively. And the further comparison shows that the sample entropy performs even better than the / power ratio. It is suggested that nonlinear dynamical parameters may be indispensable for a robust attention recognition system. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Divided nevus of the eyelid: successful treatment with CO2 laser," by Y. Zeng in the 2015 issue.

Objective: To investigate the feasibility of immediate breast and nipple-areola reconstruction after skin-sparing mastectomy., Methods: 24 patients who received skin-sparing mastectomy underwent immediate breast reconstruction with or without breast implants. The nipple-areola complex is also reconstructed with the skin paddle of the latissimus dorsi flap in one stage., Results: All the latissimus dorsi myocutaneous flaps survived completely. Partial necrosis happened in two reconstructed nipples which healed after dress changing. The follow-up period ranged from 6 to 12 months. 3 patients presented with capsular contracture (Baker I), with no necessary of surgical revision. The retraction rate of reconstructed nipples projection is 35.4% at 6 months postoperatively and 38.6% at 12 months postoperatively. 91.7% of patients were satisfied or very satisfied with the breast shape, while 83.3% were satisfied or very satisfied with the breast volume. All the patients considered the reconstructed nipple very good, while 91.6% were satisfied with the nipple projection. 91.7% considered immediate nipple reconstruction to be very important, and 8.3% considered it to be important. 66.7% considered the new breast could replace the breast they had lost, and 8.3% considered that it could not., Conclusion: For skin-sparing mastectomy, immediate breast and nipple reconstruction can achieve good aesthetic results.