Wyniki wyszukiwania - BazTech

1

Study on the influence of pin shaft clearance on the bearing performance of the hydraulic support

Shunyi Du, Yang Yang

Eksploatacja i Niezawodność

|

2023

|

Vol. 25, no. 4

art. no. 174367

EN

The pin clearance is a significant factor affecting the bearing capacity of the hydraulic support, but the effect of the pin clearance is often neglected in the current studies. Therefore, on the basis of considering the Equal stiffness spring damping system of the column, the dynamic simulation model of the hydraulic support without clearance was constructed to study the static bearing capacity of the hydraulic support. Moreover, as per the contact model of the connectingpin clearance, the dynamic simulation model of the single-pin clearance hydraulic support was established. The effect of single pin clearance on the load of the front and rear columns of the hydraulic support and the transmission force at key bearing points was analyzed. Meanwhile, the influence of single pin clearance at different positions on the bearing capacity of the hydraulic support was compared. Through the design of orthogonal test, the change of the transmission force of the bearing points under the coupling of multi-pin clearance was studied.

2

S-modeS-model for project cost management in value engineering for construction companies

Yang Yang, Xiao Wanxin, Lyshenko Margarita, Zhang Yang

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

|

Vol. 71, nr 6

art. no. e146617

EN

Today’s fast-changing environment for construction companies requires rapid responses and adaptation of their projects. Despite the multitude of tools applied for project cost management in engineering and construction companies, there is a need to form comprehensive solutions. The purpose of the study is to form a methodological approach to project cost management in the field of engineering construction based on alternative models to diagnose the development, assessment and selection of functional areas and content of cost management in the construction project, which allows one to increase adaptability and flexibility in the process of its implementation. The basis of research methodology is modeling, which allows one to adjust the economic and financial flows based on three S-curves, one for each component of the total cost of the work: direct costs, indirect costs and reserves. These curves include the direct cost curve for the main purchasing packages as well. This brings financial flows closer to reality because it is possible to adjust the S-curves according to the behavior of each subsystem. The contribution of the study is the proposed approach of integrating concepts related to the coordination and development of project design and production management (lean construction), forming a “3D model of management”, in a broad and comprehensive management system. It assumes a comprehensive and complete way to manage civil engineering projects. The proposed methodological approach can make a significant contribution to the preparation of forecasts and estimates by planners and controllers in the context of construction projects.

3

Research on Scattering Feature Extraction of Underwater Moving Cluster Targets Based on the Highlight Model

Yang Yang, Fan Jun, Wang Bing

Archives of Acoustics

|

2023

|

Vol. 48, No. 2

235--247

EN

In detecting cluster targets in ports or near-shore waters, the echo amplitude is seriously disturbed by interface reverberation, which leads to the distortion of the traditional target intensity characteristics, and the appearance of multiple targets in the same or adjacent beam leads to fuzzy feature recognition. Studying and extracting spatial distribution scale and motion features that reflect the information on cluster targets physics can improve the representation accuracy of cluster target characteristics. Based on the highlight model of target acoustic scattering, the target azimuth tendency is accurately estimated by the splitting beam method to fit the spatial geometric scale formed by multiple highlights. The instantaneous frequencies of highlights are extracted from the time-frequency domain, the Doppler shift of the highlights is calculated, and the motion state of the highlights is estimated. Based on the above processing method, target highlights’ orientation, spatial scale and motion characteristics are fused, and the multiple moving highlights of typical formation distribution in the same beam are accurately identified. The features are applied to processing acoustic scattering data of multiple moving unmanned underwater vehicles (UUVs) on a lake. The results show that multiple small moving underwater targets can be effectively recognized according to the highlight scattering characteristics.

4

Improving the resolution of seismic data based on S transform and modified variational mode decomposition, an application to Songliao Basin, Northeast China

Liu Siqin, Zhou Zhusheng, Peng Sanxi, Yang Yang, Zeng Weizu, Chen Keyang

Acta Geophysica

|

2022

|

Vol. 70, no 3

1103--1113

EN

The sandstone of the lithologic reservoir in Songliao Basin is characterized by thin vertical thickness and rapid lateral pinch outs, which make it difficult to identify and describe the sandstone due to insufficient resolution of existing seismic data. To solve this problem, a method based on S-transform and modified variational mode decomposition is proposed to improve the resolution in the time–frequency domain by cepstrum deconvolution. Firstly, the time–frequency spectrum of seismic records is obtained by generalized S-transform; then it is transformed into cepstrum; and the wavelet amplitude spectrum is extracted by modified variational mode decomposition with permutation entropy, to realize the time–frequency domain deconvolution of cepstrum. After improving the resolution of seismic data in the study area, the frequency band of the data is broadened by more than 20%. After frequency expansion, the seismic refection structure reflects the sedimentary characteristics of the actual sandstone in the area. The seismic refection has a good correspondence with the well point sandstone, and the thin sandstone is clearly depicted. It is fully verified that this method can effectively improve the resolution of seismic data and has the characteristics of relative amplitude preservation.

5

Sustainable water management strategies from a historical landscape - case study of Ganzhou, China

Ge Dong Ning, Yang Yang, Fekete Albert

Teka Komisji Urbanistyki i Architektury Oddział PAN w Krakowie

|

2021

|

T. 49

325--332

EN

Starting from the consideration that sustainability of landscape heritage is logically coupled with today’s sustainable development needs, the research explores the general ideas, methods and strategies of ancient Chinese urban water management. Based on the traditional Chinese water management experience from the ancient city of Ganzhou, the paper - analyses the current water landscape heritage in Jiangxi Province, China. Based on the historic experience and knowledge introduced and analyzed in the case study of Ganzhou, it is possible to define rainwater management principles and sustainable development strategies for modern urban landscape that could be the basis of a new research perspective in facing today’s climate anomalies.

PL

Zaczynając od konstatacji, że zrównoważony rozwój dziedzictwa krajobrazowego jest logicznie połączony z dzisiejszymi potrzebami zrównoważonego rozwoju, badania wskazują ogólne pomysły, metody i strategie starożytnej chińskiej miejskiej gospodarki wodnej. Bazując na tradycyjnych chińskich doświadczeniach w zakresie gospodarki wodnej ze starożytnego miasta Ganzhou, artykuł analizuje obecne dziedzictwo krajobrazu wodnego w prowincji Jiangxi w Chinach. W oparciu o historyczne doświadczenie i wiedzę wprowadzoną oraz przeanalizowaną w studium przypadku Ganzhou, możliwe jest zdefiniowanie zasad zarządzania wodą deszczową i strategii zrównoważonego rozwoju dla nowoczesnego krajobrazu miejskiego, które mogłyby być podstawą nowej perspektywy badawczej w obliczu dzisiejszych anomalii klimatycznych.

6

Seismic signal de noising using time–frequency peak fltering based on empirical wavelet transform

Liu Naihao, Yang Yang, Li Zhen, Gao Jinghuai, Jiang Xiudi, Pan Shulin

Acta Geophysica

|

2020

|

Vol. 68, no. 2

425--434

EN

Seismic noise suppression plays an important role in seismic data processing and interpretation. The time–frequency peak fltering (TFPF) is a classical method for seismic noise attenuation defned in the time–frequency domain. Nevertheless, we obtain serious attenuation for the seismic signal amplitude when choosing a wide window of TFPF. It is an unsolved issue for TFPF to select a suitable window width for attenuating seismic noise efectively and preserving valid signal amplitude efectively. To overcome the disadvantage of TFPF, we introduce the empirical wavelet transform (EWT) to improve the fltered results produced by TFPF. We name the proposed seismic de-noising workfow as the TFPF based on EWT (TFPFEWT). We frst introduce EWT to decompose a non-stationary seismic trace into a couple of intrinsic mode functions (IMFs) with diferent dominant frequencies. Then, we apply TFPF to the chosen IMFs for noise attenuation, which are selected by using a defned reference formula. At last, we add the fltered IMFs and the unprocessed ones to obtain the fltered seismic signal. Synthetic data and 3D feld data examples prove the validity and efectiveness of the TFPF-EWT for both attenuating random noise and preserving valid seismic amplitude.

7

Study on leaching kinetics of laterite ore using hydrochloric acid

Li Jinhui, Xu Zhifeng, Wang Ruixiang, Gao Yang, Yang Yang

Physicochemical Problems of Mineral Processing

|

2019

|

Vol. 55, iss. 3

711--720

EN

The process of atmosphere-pressure acid leaching of laterites has attracted considerable attention in the nickel industry in recent years. However, the leaching kinetics of laterite using hydrochloride acid has not yet been fully researched. In this paper, the mineral analysis of the ore was carried out, and the leaching mechanism of different minerals at different time was studied comprehensively. The kinetics analysis of the leaching process of nickel, cobalt and manganese showed that the kinetics model of diffusion controlling was suitable and could be described by the linear equation, 1-3(1-a)2/3+2(1-a)=k2t. Based on the linear equation and the Arrhenius equation, the values of activation energy of metal leaching can be deduced (11.56 kJ/mol for nickel, 11.26 kJ/mol for cobalt and 10.77 kJ/mol for manganese). Study of leaching mechanism shows that the order of these minerals dissolution is: goethite, lizardite, magnetite and hematite. Due to the original or product of silica, magnetite, hematite and talc, they can form the solid film which hinders the leaching of valuable metals. Thus, the diffusion controlling step is inner diffusion, namely solid film diffusion controlling.