Statistical energy analysis as a tool for quantifying sound and vibration transmission paths

When a complex structure is excited in several different ways by different sources, the sea energy balance equations result in a set of linear equations that can be used to calculate loss factors, coupling loss factors or net energy flows and incoming powers. If certain symmetry relations are used, and/or if some prior knowledge about the system is available, the set of linear equations is overdetermined and can be solved by a least square technique. A good indicator for the direction of the energy flow is the SEA temperature of the subsystems. Experiments and computer simulations performed on three plate arrangements gave in general good results when the coupling was weak and there were more than three modes in the frequency band of interest. Not so good results were obtained when a small energy flow has to be measured as the difference of large quantities.

Author(s):  
Ni Ketut Mirahayuni ◽  
Susie Chrismalia Garnida ◽  
Mateus Rudi Supsiadji

Abstract. Translating complex structures have always been a challenge for a translator since the structures can be densed with ideas and particular logical relations. The purpose of translation is reproducing texts into another language to make them available to wider readerships. Since language is not merely classification of a set of universal and general concept, that each language articulates or organizes the world differently, the concepts in one language can be radically different from another. One issue in translation is the difference among languages, that the wider gaps between the source and target languages may bring greater problems of transfer of message from the source into the target languages (Culler, 1976). Problematic factors involved in translation include meaning, style, proverbs, idioms and others. A number of translation procedures and strategies have been discussed to solve translation problems. This article presents analysis of complex structures in scientific Indonesian, the problems and effects on translation into English. The study involves data taken from two research article papers in Indonesian to be translated into English. The results of the analysis show seven (7) problems of Indonesian complex structures, whose effect on translation process can be grouped into two: complex structures related to grammar (including: complex structure with incomplete information, run-on sentences, redundancy , sentence elements with inequal semantic relation, and logical relation and choice of conjunctor) and complex structures related to information processing in discourse (including: front-weight- structure and thematic structure with changes of Theme element). Problems related to grammar may be solved with language economy and accuracy while those related to discourse may be solved with understanding information packaging patterns in the target language discourse. Keywords: scientific language, complex structures, translation


Author(s):  
G Mazzeo ◽  
MN Ichchou ◽  
G Petrone ◽  
O Bareille ◽  
S De Rosa ◽  
...  

In the wind tunnel facility, a test structure is often used for measuring its vibrational response to the aerodynamic excitation. A support is needed to sustaining the structure and it is mandatory that this support does not influence the vibrational energy to be measured. To this aim, the maximum amount of energy decoupling between the structure and the support is desired. This work is focused around a quick method to estimate this decoupling by using simplified models for the Turbulent Boundary Layer (TBL) excitation and for the structural response. Specifically, the Equivalent Rain-on-the-roof excitation is invoked with a Statistical Energy Analysis model for the structure. Some simple design rules are proposed and based on little information leading to foresee the difference of vibrational velocity levels between the two structural systems. A simplified test-case is used for the first investigations and a complex structure is finally conceived thinking to vibroacoustic measurements in a large wind tunnel facility. Although some results are largely expected, the global approach is promising.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Huan-Hua Xu ◽  
Zhen-Hong Jiang ◽  
Cong-Shu Huang ◽  
Yu-Ting Sun ◽  
Long-Long Xu ◽  
...  

Abstract Background OPD and OPD' are the two main active components of Ophiopogon japonicas in Shenmai injection (SMI). Being isomers of each other, they are supposed to have similar pharmacological activities, but the actual situation is complicated. The difference of hemolytic behavior between OPD and OPD' in vivo and in vitro was discovered and reported by our group for the first time. In vitro, only OPD' showed hemolysis reaction, while in vivo, both OPD and OPD' caused hemolysis. In vitro, the primary cause of hemolysis has been confirmed to be related to the difference between physical and chemical properties of OPD and OPD'. In vivo, although there is a possible explanation for this phenomenon, the one is that OPD is bio-transformed into OPD' or its analogues in vivo, the other one is that both OPD and OPD' were metabolized into more activated forms for hemolysis. However, the mechanism of hemolysis in vivo is still unclear, especially the existing literature are still difficult to explain why OPD shows the inconsistent hemolysis behavior in vivo and in vitro. Therefore, the study of hemolysis of OPD and OPD' in vivo is of great practical significance in response to the increase of adverse events of SMI. Methods Aiming at the hemolysis in vivo, this manuscript adopted untargeted metabolomics and lipidomics technology to preliminarily explore the changes of plasma metabolites and lipids of OPD- and OPD'-treated rats. Metabolomics and lipidomics analyses were performed on ultra-high performance liquid chromatography (UPLC) system tandem with different mass spectrometers (MS) and different columns respectively. Multivariate statistical approaches such as principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA) were applied to screen the differential metabolites and lipids. Results Both OPD and OPD' groups experienced hemolysis, Changes in endogenous differential metabolites and differential lipids, enrichment of differential metabolic pathways, and correlation analysis of differential metabolites and lipids all indicated that the causes of hemolysis by OPD and OPD' were closely related to the interference of phospholipid metabolism. Conclusions This study provided a comprehensive description of metabolomics and lipidomics changes between OPD- and OPD'-treated rats, it would add to the knowledge base of the field, which also provided scientific guidance for the subsequent mechanism research. However, the underlying mechanism require further research.


1968 ◽  
Vol 58 (3) ◽  
pp. 977-991
Author(s):  
Richard A. Haubrich

abstract Arrays of detectors placed at discrete points are often used in problems requiring high resolution in wave number for a limited number of detectors. The resolution performance of an array depends on the positions of detectors as well as the data processing of the array output. The performance can be expressed in terms of the “spectrum window”. Spectrum windows may be designed by a general least-square fit procedure. An alternate approach is to design the array to obtain the largest uniformly spaced coarray, the set of points which includes all the difference spacings of the array. Some designs obtained from the two methods are given and compared.


2021 ◽  
Vol 75 (3) ◽  
pp. 70-75
Author(s):  
B.E. Yagaliyeva ◽  
◽  
B.B. Akhmetov ◽  
V.A. Lakhno ◽  
G.S. Zhilkishbayeva ◽  
...  

A model for managing the investment process is proposed, based on the example of investing in cybersecurity of national scale informatization objects, taking into account the multifactorial nature of this process. The difference between this model and those previously developed is that, firstly, it considers the investment process as a complex structure, for which it is not enough to model it as a one-factor category. Second, our model is based on the solution of a bilinear multi-step quality game with several terminal surfaces. The solution is obtained within the framework of the scheme of a new class of bilinear multistage games describing the interaction of objects in a multidimensional space. Consideration of the investment process in such a setting makes it possible to adequately describe the process of searching for rational strategies of players in the course of investing in information technologies. The study made it possible to implement the program code of the model in the MatLab simulation environment.


2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Heriyanto Heriyanto ◽  
Asrol Asrol ◽  
Detri Karya ◽  
Verry Yarda Ningsih

Heriyanto et al, 2018. Analysis of the Production Factors of the People's Palm Oil According to the Land Typology in Indragiri Hilir Regency, Riau Province. JLSO 7(1): Palm oil commodities are one of the plantation sub-sector commodities that increase the income of farmers and the community, provide processing industry raw materials that create added value. The land cultivated by independent oil palm farmers consists of land land, tidal peatlands, coastal peatlands and coastal land. The difference in typology of this land will contribute to different production. The research aimed to analyze the oil palm production and the dominant factor affecting oil palm production according to the typology of land in Indragiri Hilir Riau Province. The data were analyzed using descriptive statistics and built multiple regression models with the dummy variable method of Ordinary Least Square (OLS). The results of the study showed that the production of oil palm cultivation on land is the highest compared to the typology of tidal peatland, coastal peat and coastal land. The dominant factors affecting palm oil production in Indragiri Hilir Regency were the amount of fertilizer use, labor, age of plants, herbicides and dummy typology of land. In order to obtain optimal production, this study recommended doing oil palm farming in accordance with the correct cultivation techniques in accordance with the characteristics of land typology. Besides that the use of balanced fertilizer (elements of N, P, and K) in accordance with the recommended needed to be applied.


2007 ◽  
Vol 39 (2) ◽  
pp. 271-288
Author(s):  
Dusanka Lazarevic ◽  
Biljana Trebjesanin

This paper presents the results of the research of the characteristics of achievement motive of future physical education teachers. Starting from understanding of the importance of achievement motive for the successful accomplishment of professional goals and roles of teachers, the aim of our research is to examine the level of achievement motive, the characteristics of its structure and differences according to gender. The instrument MOP2002 (Francesko et al., 2002a) was applied, which presupposes the complex structure of this motive. The sample consisted of 373 students (263 male and 110 female) of the Faculty of Sport and Physical Education in Belgrade. The results show that their achievement motive is characterized by the tendency towards high level of presence, and its structure is in the largest degree determined by the components accomplishing goals as a source of pleasure and perseverance in accomplishing goals, which is followed by orientation towards planning. The component competing with others is demonstrated in a moderate degree and it is least expressed. It was shown that female students have a larger degree of achievement motive when compared to male students, and accomplishing goals as a source of pleasure and perseverance in accomplishing goals mostly contribute to the difference in structure of achievement motive. It can be expected that the achievement motive, with the structure and degree of presence determined in our respondents, will contribute that they, as future teachers, become a good motivational model and the creators of a desirable motivational climate.


Author(s):  
Gretchen D. Oliver ◽  
Kyle Wasserberger ◽  
Anne de Swart ◽  
Kenzie Friesen ◽  
Jessica Downs ◽  
...  

Context Inadequate hip range of motion (ROM) and isometric strength (ISO) may interfere with energy flow through the kinetic chain and result in increased injury susceptibility. Objective To examine the relationship of hip ROM and ISO with energy flow through the trunk and pitching-arm segments during the windmill softball pitch in youth athletes. A subsequent purpose was to examine the relationship between energy flow and pitch speed. Design Descriptive laboratory study. Setting University research laboratory. Patients or Other Participants A sample of 29 youth softball pitchers (age = 11.2 ± 1.3 years, height = 155.0 ± 10.4 cm, mass = 53.2 ± 12.6 kg). Main Outcome Measure(s) Bilateral hip internal-rotation and external-rotation (ER) ROM and ISO were measured. Net energy outflow and peak rates of energy outflow from the distal ends of the trunk, humerus, and forearm were calculated for the acceleration phase of the windmill softball pitch, and pitch speed was measured. Results Regression analysis revealed an effect of drive-hip ER ISO on the net energy flow out of the distal ends of the trunk (P = .045) and humerus (P = .002). Specifically, increased drive-hip ER ISO was associated with increased net energy outflow from the trunk to the humerus and from the humerus to the forearm. No significant effects of hip ROM or other hip ISO measures were observed. Additionally, pitchers who achieved higher peak rates of distal outflow tended to achieve higher pitch speeds. Conclusions An association was present between drive-hip ER ISO and the net energy flow out of the distal ends of the trunk and humerus during the acceleration phase of the windmill softball pitch, emphasizing the importance of hip and lower body strength in executing the whole-body windmill pitch. Overall, energy-flow analysis is an interesting new way to analyze pitching mechanics and will aid in furthering our understanding of performance and injury risk in windmill softball pitching.


1993 ◽  
Vol 115 (4) ◽  
pp. 995-1001 ◽  
Author(s):  
F. L. Litvin ◽  
C. Kuan ◽  
J. C. Wang ◽  
R. F. Handschuh ◽  
J. Masseth ◽  
...  

The deviations of a gear’s real tooth surface from the theoretical surface are determined by coordinate measurements at the grid of the surface. A method has been developed to transform the deviations from Cartesian coordinates to those along the normal at the measurement locations. Equations are derived that relate the first order deviations with the adjustment to the manufacturing machine tool settings. The deviations of the entire surface are minimized. The minimization is achieved by application of the least-square method for an overdetermined system of linear equations. The proposed method is illustrated with a numerical example for hypoid gear and pinion.


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