POLYPHONIC GENRES IN PIANO CREATIVITY OF CHINESE COMPOSERS

Statement of the problem. The twentieth century marked an increased interest in polyphonic music. The geography of polyphonic works for piano expanded significantly and a creative development of many Chinese composers, writing polyphonic piano pieces, took place. Today, polyphonic pieces make up a significant part of the piano repertoire in China, but they are little studied by musicologists and performers. The objective of this study – to reveal the contribution of Chinese composers to the creation of polyphonic piano repertoire of the XX – early XXI century. Analysis of the research and publications on the theme. А large number of modern authors study polyphony from the point of physical and mathematical research methods (Igarashi, Yu. & Ito, Masashi & Ito, Akinori, 2013; Weiwei, Zhang & Zhe, Chen, & Fuliang, Yin, 2016; Li, Xiaoquan et al. others, 2018). This approach does not reveal the factual musical component of polyphonic genres. In the 20th century, musicologists explored polyphony in musical folklore (Wiant, 1936; Fan Zuyin, 2004; Li Hong, 2015) and in professional Chinese composing (Sun Wei-bo, 2006, Winzenburg, 2018). The scientific novelty. This article studies the role of Chinese composers in the development of the world polyphonic piano repertoire of the XX – early XXI century. The methodological basis for the analysis of polyphonic works was the theoretical concepts of P. Hindemith, Peng Cheng, Fang Zuin, Li Hong, Sun Wei-bo. The results of the study. The research outcomes demonstrate the evolutionary development of the genre diversity of Chinese piano polyphony as well as those composers who created magnificent musical pieces. Conclusions. Chinese composers have fully mastered the art of modern counterpoint, represented by the genres of polyphonic program pieces (He Lu Ting), invention (Xiao Shu Xian, Du Qian, Sun Yun Yin, Chen Chen Quang), polyphonic suite (Ma Gui), large polyphonic cycle ( He Shao, Chen Hua Do, Xiao Shu Xian), fugue (Li Jun Yong, Yu Su Yan, Chen Gang, Tian Lei Lei, Duan Ping Tai, Zheng Zhong, Xiao Shu Xian) and small cycle “Prelude and Fugue” (Ding Shan Te, Chen Zhi Ming, Wang Li Shan). Creatively assimilating and rethinking the experience of Western polyphonists, Chinese composers have filled their polyphonic works with national features, firmly linking them with the origins of Chinese traditional and folk music. The polyphonic way of transmitting musical material becomes the most expressive at the moments of profound creativity and musical dramatization.

Acetylenic Carbon-Containing Stable Five-Membered Metallacycles

Due to the linear property around an acetylenic carbon, the introduction of such an atom to a small cycle would result in high ring strain. Currently, the smallest isolated rings are five-membered, including metallacycloalkynes and metallapentalynes. Both types contain at least one unusual small bond angle around the acetylenic carbon, thus exhibiting abnormal reactivities. This feature article gives a comprehensive overview on these two kind complexes. The synthesis and reactivities are extensively described, the source of stability is presented, and the future prospect is discussed. The article aims to provide a better development for the chemical diversity of five-membered metallacycloalkynes and metallapentalynes.

A Modified TurboEdit Cycle-Slip Detection and Correction Method for Dual-Frequency Smartphone GNSS Observation

Recently, some smartphone manufacturers have subsequently released dual-frequency GNSS smartphones. With dual-frequency observations, the positioning performance is expected to be significantly improved. Cycle-slip detection and correction play an important role in high-precision GNSS positioning, such as precise point positioning (PPP) and real-time kinematic (RTK) positioning. The TurboEdit method utilizes Melbourne–Wübbena (MW) and phase ionospheric residual (PIR) combinations to detect cycle-slips, and it is widely used in the data processing applications for geodetic GNSS receivers. The smartphone pseudorange observations are proved to be much noisier than those collected with geodetic GNSS receivers. Due to the poor pseudorange observation, the MW combination would be difficult to detect small cycle-slips. In addition, some specific cycle-slip combinations, where the ratio of cycle-slip values at different carrier frequencies is close to the frequency ratio, are also difficult to be detected by PIR combination. As a consequence, the traditional TurboEdit method may fail to detect specific small cycle-slip combinations. In this contribution, we develop a modified TurboEdit cycle-slip detection and correction method for dual-frequency smartphone GNSS observations. At first, MW and PIR combinations are adopted to detect cycle-slips by comparing these two combinations with moving-window average values. Then, the epoch-differenced wide-lane combinations are used to estimate the changes of smartphone position and clock bias, and the cycle-slip is identified by checking the largest normalized residual whether it exceeds a predefined threshold value. The process of estimation and cycle-slip identification is implemented in an iterative way until there is no over-limit residual or there is no redundant measurement. At last, the cycle-slip values at each frequency are estimated with the epoch-differenced wide-lane and ionosphere-free combinations, and the least-square ambiguity decorrelation adjustment (LAMBDA) method is adopted to further obtain an integer solution. The proposed method has been verified with 1 Hz dual-frequency smartphone GNSS data. The results show that the modified TurboEdit method can effectively detect and correct even for specific small cycle-slip combinations, e.g., (4, 3), which is difficult to be detected with the traditional TurboEdit method.

Piano cycles by Roman Tsis: stylistic and expressive aspects

The task of this article is to consider the genre specifics of the cycle of preludes and a small cycle of program pieces, the interconnection of traditions and innovative searches in the field of creating an executive- didactic repertoire for pianists on the example of the author's collection of Roman Tsis. The methodology of the research is to use theoretical and structural-system methods in the analysis of sources and samples of the didactic repertoire of different authors; comparative - in the study of the features of the individual author's style as the basis for mastering technical and sound creation tasks. The scientific novelty lies in the fact that for the first time the author analyzes the interconnection of traditions and innovative searches in the field of creating an executive-didactic repertoire for pianists in the class of general and specialized piano in the genre system of a cycle of programmatic preludes and small cycles with the help of contemporary composer creativity. R. Tsis's piano cycles have a significant didactic potential from the standpoint of understanding interpretative tasks in terms of different stylistics, genre varieties, principles of texture organization, composing techniques and sounding aspects. With a rather modest technical arsenal and small scale compositions, they reproduce a variety of formative techniques and principles of melodic development. Due to the presence of small cycles and the monogamous suite of preludes, it is possible to simulate the selection of the repertoire depending on the tastes, preferences and interpretive-didactic needs of a particular representative of the class of general and specialized piano. This approach allows individually to form the most appropriate set of works that would gradually build and develop the aesthetic and performing-interpretive potential of the student, his ability to solve artistic tasks and overcome technical difficulties. The key to success is to engage in a multi-role and multi-genre repertoire with the ability to separate individual thumbnails or, conversely, simulate suites-cyclic structures.

Detection of Ratcheting in Finite Element Calculations

The distinction between a ratcheting and non-ratcheting response is critical for many high temperature design methods. Non-ratcheting is generally considered safe — deformation remain bounded over the lifetime of the component — while ratcheting is undesirable. As a particular example, the elastic perfectly-plastic (EPP) design methods described in recent ASME Section III, Division 5 code cases require a designer to distinguish ratcheting from non-ratcheting for finite element analyses using a relatively simple, elastic perfectly-plastic constitutive response. However, it can be quite difficult to distinguish these two deformation regimes using finite element (FE) analysis particularly in the case where the actual ratcheting strain is small. In practice FE analysis of structures that are analytically in either the plastic shakedown or ratcheting regimes will result in small, cycle-to-cycle accumulated strains characteristic of ratcheting. Distinguishing false ratcheting — the structure is actually in the plastic shakedown regime — from true ratcheting can be challenging. We describe the characteristics of nonlinear FE analysis that cause these false ratcheting strains and describe practical methods for distinguishing a ratcheting from a non-ratcheting response.

A New Cycle Slip Detection and Repair Method for Single-Frequency GNSS Data

Cycle slip detection for single frequency Global Navigation Satellite System (GNSS) data is currently mainly based on measurement modelling or prediction, which cannot be effectively performed for kinematic applications and it is difficult to detect or repair small cycle slips such as half-cycle slips. In this paper, a new method that is based on the total differential of ambiguity and Least-Squares Adjustment (LSA) for cycle slip detection and repair is introduced and validated. This method utilises only carrier-phase observations to build an ambiguity function. LSA is then conducted for detecting and repairing cycle slips, where the coordinate and cycle slips are obtained successively. The performance of this method is assessed through processing short and long baselines in static and kinematic modes and the impact of linearization and atmospheric errors are analysed at the same time under a controlled variable method. The results indicate this method is very effective and reliable in detecting and repairing multiple cycle slips, especially small cycle slips.