信息化手段对音乐剧教学的影响

随着科学技术的发展与进步,信息化技术在现代社会生活中的应用越来越普及。本文以信息化技术为手段,具体研究该技术对北京舞蹈学院音乐剧系教学与实践的影响。本文通过采用文献资料法和观察法,通过查阅文献资料与互联1网视频资料,结合笔者高校音乐剧教学实践,具体阐述信息化技术的优势、信息化技术促进线上音乐剧教学、信息化技术有利于音乐剧研讨与推广这三方面的内容,以现代化音乐软件和具体的教学实践为载体,充分利用信息化技术手段,使高校音乐剧教学内容更加多元,教学模式更加丰富。

Face mask detection algorithm based on HSV+HOG features and SVM

To automatically detecting whether a person is wearing mask properly,we propose a face mask detection algorithm based on hue-saturation-value(HSV)+histogram of oriented gradient(HOG)features and support vector machines(SVM).Firstly,human face and five feature points are detected with RetinaFace face detection algorithm.The feature points are used to locate to mouth and nose region,and HSV+HOG features of this region are extracted and input to SVM for training to realize detection of wearing masks or not.Secondly,RetinaFace is used to locate to nasal tip area of face,and YCrCb elliptical skin tone model is used to detect the exposure of skin in the nasal tip area,and the optimal classification threshold can be found to determine whether the wear is properly according to experimental results.Experiments show that the accuracy of detecting whether mask is worn can reach 97.9%,and the accuracy of detecting whether mask is worn correctly can reach 87.55%,which verifies the feasibility of the algorithm.

Analysis of Vibration Frequencies of Piezoelectric Ceramic Rings as Ultrasonic Transducers in Welding of Facial Mask Production

The explosive demands for facial masks as vital personal protection equipment(PPE)in the wake of Covid-19 have challenged many industries and enterprises in technology and capacity,and the piezoelectric ceramic(PZT)transducers for the production of facial masks in the welding process are in heavy demand.In the earlier days of the epidemic,the supply of ceramic transducers cannot meet its increasing demands,and efforts in materials,development,and production are mobilized to provide the transducers to mask producers for quick production.The simplest solution is presented with the employment of Rayleigh-Ritz method for the vibration analysis,then different materials can be selected to achieve the required frequency and energy standards.The fully tailored method and results can be utilized by the engineers for quick development of the PZT transducers to perform precise function in welding.

Development and Implementation of Antiradiation Respirator ＂ARR-1＂ for Use in Uranium Mining

It has been developed and implemented for use antiradiation mask ＂ARR-I＂ for use in the uranium industry. The outer layer is treated with a special solution with anti-gas composition, which holds the gaseous radioactive isotopes.

口罩陷阱

进入了冬天，甲流也变得更加“猖狂”，这不，好多同学都停课了，在家复习呢。一天，海力妈妈让海力去药店买几个口罩，叮嘱他一定要买一种专防甲流的新型口罩，说甲流抑制率达92％以上。

Thermochemical recycling of waste disposable facemasks in a non-electrically powered system

The COVID-19 pandemic encouraged the use of plastic-based personal protective equipment (PPE), which aidedgreatly in its management. However, the increased production and usage of these PPEs put a strain on the environment,especially in developing and underdeveloped countries. This has led various researchers to study low-costand effective technologies for the recycling of these materials. One such material is disposable facemasks. However,previous studies have only been able to engage electrically powered reactors for their thermochemical conversion,which is a challenge as these reactors cannot be used in regions with an insufficient supply of electricity. In thisstudy, the authors utilized a biomass-powered reactor for the conversion of waste disposable facemasks and almondleaves into hybrid biochar. The reactor, which is relatively cheap, simple to use, environmentally friendly, and modifiedfor biochar production, is biomass-powered. The co-carbonization process, which lasted 100 min, produced a 46%biochar yield, which is higher than previously obtained biochar yields by other researchers. The biochar thus obtainedwas characterized to determine its properties. FTIR analysis showed that the biochar contained functional groupssuch as alkenes, alkynes, hydroxyls, amines, and carbonyls. The EDX analysis revealed that the biochar was primarilymade of carbon, tellurium, oxygen, and calcium in the ratios of 57%, 19%, 9%, and 7%, respectively. The inclusion ofthe facemask decreased the surface area and porosity of the biochar material, as evidenced by its surface area andpore characteristics.

漫看

烟囱和圣诞老人 （这样的烟囱，让圣诞老人如何“下手”？）

Convergence and error estimate of cascade algorithms with infinitely supported masks in L_p(R^s)

The cascade algorithm plays an important role in computer graphics and wavelet analysis.In this paper,we first investigate the convergence of cascade algorithms associated with a polynomially decaying mask and a general dilation matrix in L p (R s) (1 p ∞) spaces,and then we give an error estimate of the cascade algorithms associated with truncated masks.It is proved that under some appropriate conditions if the cascade algorithm associated with a polynomially decaying mask converges in the L p-norm,then the cascade algorithms associated with the truncated masks also converge in the L p-norm.Moreover,the error between the two resulting limit functions is estimated in terms of the masks.