scholarly journals Analysis of balancing of four stroke V6 engines

2013 ◽  
Vol 155 (4) ◽  
pp. 44-55
Author(s):  
Ryszard MOSAKOWSKI
Keyword(s):  
Moment Of Inertia ◽  
Reciprocating Motion ◽  
Connecting Rod ◽  
Bank Angle ◽  
First Order ◽  
Cylinder Bank ◽  
The Moment ◽  
Inertia Forces ◽  
Selection Of

Analysis of balance of V6 engines with a common-pin crankshaft depending on a cylinder bank angle and the crank radius to connecting rod length ratios l based on the relations derived is presented in the paper. The bank angles providing the lowest moment of inertia forces in reciprocating motion for selected l values were determined. The position of the plane of the main counterweights in order to maximum balance of the moment of the first order inertia forces and degree of its balancing in the function of the cylinder bank angle were also defined in the paper. The position of the balancing shaft with respect to the crankshaft to fully balance the moments of the first order inertia forces was also determined. Apart from the quality of balancing, also other criteria for the selection of the cylinder bank angle of vehicle engines were indicated in the paper.

scholarly journals Comparative analysis of balancing of V6 engines with common- and split-pin crankshafts

2014 ◽  
Vol 156 (1) ◽  
pp. 3-12
Author(s):  
Ryszard MOSAKOWSKI
Keyword(s):  
Comparative Analysis ◽  
Point Of View ◽  
Reciprocating Motion ◽  
Bank Angle ◽  
Moments Of Inertia ◽  
Cylinder Bank ◽  
Mathematical Relation ◽  
Inertia Forces ◽  
Mathematical Relations

An analysis of balancing of V6 engines equipped with split-pin crankshafts with any cylinder bank angle based on the mathematical relations derived in the paper was carried out. A comparison of the quality of their balancing with engines equipped with common-pin crankshafts was also carried out. The bank angle ranges beneficial for balancing of moments of inertia forces in reciprocating motion were determined. A mathematical relation on the optimum value of the main counterweights in the function of the cylinder bank angle was derived as well. The advantages of the split-pin crankshafts from the point of view of balancing were also indicated also.

scholarly journals Analysis of balancing of six-cylinder in-line two-stroke internal combustion engines

2009 ◽  
Vol 139 (4) ◽  
pp. 22-33
Author(s):  
Ryszard MOSAKOWSKI
Keyword(s):  
Comparative Analysis ◽  
Internal Combustion Engines ◽  
Second Order ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Moments Of Inertia ◽  
First Order ◽  
L Value ◽  
The Moment ◽  
Inertia Forces

Simple relations describing the resultant moments of inertia forces of the first and second order for all sixty possible configurations of the crankshaft in two-stroke four-cylinder engine have been derived in the paper. A comparative analysis of the crankshafts with different arrangements of cranks have been carried out with respect to the resultant moments of the first and second order inertia forces. The comparison has been carried out for two values of the crank throw to connecting rod length ratio, namely l = 0.3 and l = 0.5. The outcomes of the comparative analysis indicate that irrespective of the l value, within the range of its values having practical meanings, the arrangement of cranks 1-5-3-4-2-6 is the best. As a result of 50% balancing of the moment of the first order inertia forces the differences between various configurations of the crankshaft are significantly reduced and configuration 1-4-2-6-3-5 equals with respect to balancing with the commonly used configuration 1-5-3-4-2-6.

scholarly journals The Evolution of Quality of Life Assessment and Use in Dermatology

Dermatology ◽  
2019 ◽  
Vol 235 (3) ◽  
pp. 167-174 ◽  
Author(s):  
Pavel V. Chernyshov
Keyword(s):  
Quality Of Life ◽  
Skin Diseases ◽  
Life Quality ◽  
Life Assessment ◽  
Core Outcome Sets ◽  
The Moment ◽  
Development And Validation ◽  
The Impact ◽  
Selection Of

The creation of the Dermatology Life Quality Index (DLQI) questionnaire facilitated many studies on the impact of skin diseases on patients’ quality of life (QoL). Many national and international guidelines recommend QoL assessment in dermatology, and some of them contain detailed recommendations on treatment goals and changes of treatment approaches based on DLQI score banding and minimal clinically important difference. The methodology of QoL in strument development and validation is constantly becoming more rigorous. Initiatives on selection of core outcome sets for skin diseases are focused on clinical trials but may also be beneficial for clinicians. There are various benefits of using QoL information in clinical practice, but experience of this is very limited at the moment. QoL assessment in dermatology is a rapidly developing field with a gradual shift from theory to practice.

scholarly journals Validating the Methods to Process the Stress Path in Multiaxial High-Cycle Fatigue Criteria

Materials ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 206
Author(s):  
Jan Papuga ◽  
Eva Cízová ◽  
Aleksander Karolczuk
Keyword(s):  
Fatigue Strength ◽  
Equivalent Stress ◽  
Stress Path ◽  
Multiaxial Fatigue ◽  
Moment Of Inertia ◽  
Critical Plane ◽  
Strength Criteria ◽  
Multiaxial Stress State ◽  
The Moment ◽  
Selection Of

The paper discusses one of the key features in the multiaxial fatigue strength evaluation—the procedure in which the stress path is analyzed to provide relevant measures of parameters required by multiaxial criteria. The selection of this procedure affects the complete equivalent stress derived for any multiaxial load combinations. Three major concepts—the minimum circumscribed circle, minimum circumscribed ellipse, and moment of inertia methods—are described. Analytical solutions of their evaluation for multiaxial stress state with components described by harmonic functions are provided. The concepts are validated on available experimental data when included into six different multiaxial fatigue strength criteria. The results show that the moment of inertia results in too conservative results. Differences between both methods of circumscribed entities are much smaller. There are indications however that the minimum circumscribed ellipse solution works better for critical plane criteria and for the criteria based on stress tensor transformation into the Ilyushin deviatoric space. On the other hand, the minimum circumscribed ellipse solution tends to shift integral criteria to the conservative side.

scholarly journals Selection of Sport- and Racehorses

2005 ◽  
pp. 3-10
Author(s):  
Sándor Mihók
Keyword(s):  
High Performance ◽  
Decisive Role ◽  
Active Role ◽  
The Body ◽  
Second Phase ◽  
Human Needs ◽  
Equestrian Sports ◽  
The Moment ◽  
Selection Of

The utilisation of the horse has changed from time to time in response to human needs. For a few decades, it has been serving in several equestrian sports more intensively. It has also been proved that the standards for this kind of performance cannot be established in the way certain characteristics, such as the weight gain or milk production of other animal breeds can. Breeding horses for sporting comprises highly complex selection criteria.Some of these (e.g. external features, temperament, manageability and intelligence) do not put the breeder in a difficult position, but finding the traits that establishes the safety of sporting achievements poses a genetic problem.The performance of a horse for sports is a highly complex feature, which cannot easily be assessed or put down in figures. In addition, man plays a decisive role in shaping all kinds of performance of a horse at any given time by not only creating conditions for a better performance, but also by playing an active role in increasing it.The performance of the horse is mostly defined by its general aptitude to movement, ie., the regularity, clear rhythm and springiness of basic types of strides, as well as the ability to move in a naturally balanced way. Training and riding principles are based on these traits. These two together will determine about 70% of the value of the horse and its adequacy for high performance equestrian sports. In order to avoid subjectivity in determining the above variables and to increase the degree of objectivity, competent expert teams (trainers, judges, other riders) are employed to form an opinion on an individual animal.Assessing horse performance outside races does not seem to be efficient, as owing to the dominant effects of the environment, the indicator of inheritability is hardly above 0.1.Free jumping is an especially appropriate means for assessing a horse’s readiness and ability to move in an environment free of disturbing factors. In free jumping, it is especially important to judge the style of the jump. The first phase of jumping – as a sequence of movements – lasts from the moment the fore-feet touch the ground until the moment the hind-feet push off, while the second phase lasts from this moment until touching the ground. The most important task in the first phase is to make the angle of the dip of the body by the supporting fore-feet that is necessary for the jump. The quality of the jump is determined by the jumping and adequately expanded hind-legs. The intensity of pushing off and jumping done by the hind-legs can be inferred, and differences between individuals can be discerned from the shaping of the curve by the hocks and the paths of the pasterns in relation to the withers.

Mechanical Analysis of Diamond Saw Blade

2011 ◽  
Vol 480-481 ◽  
pp. 539-545 ◽  
Author(s):  
Jun De Yang ◽  
Zhong Ping Luo ◽  
Fan Lu ◽  
Yuan Wang
Keyword(s):  
Mechanical Analysis ◽  
Rock Hardness ◽  
Downward Pressure ◽  
Diamond Saw ◽  
Feeding Speed ◽  
The Moment ◽  
Saw Blade ◽  
The Impact ◽  
Selection Of

The following conclusion is drawn from detailed mechanical analysis of Diamond Saw Blade,The load on diamond is not significant in cutting. However, at the moment the blade starts in its working state, the impact on rock has significant destructiveness on diamonds. Higher linear velocity of the blade, higher rock hardness and higher feeding speed all contribute in greater impact force on the diamond from the rock. And it is also stated that the unstable quality of diamond saw blade is closely related to the selection of diamond without following the TT1 test result. When designing the diamond saw blade, the saw cutting performance of the rock should be taken into consideration, as well as the necessary analysis of the force on the blade.There are three forces exerted on the saw blade: ①vertical downward pressure;②horizontal feeding thrust;③tangential cutting force of the saw. They are discussed separately in the following.

scholarly journals Groupware for Collaborative Tailoring

2005 ◽  
Author(s):  
◽  
Alejandro Fernández
Keyword(s):  
Social System ◽  
Work Conditions ◽  
Team Work ◽  
Target System ◽  
Team Members ◽  
The Social ◽  
Group Members ◽  
The Moment ◽  
Selection Of

In everyday work, teamwork in the presence of the tools, the resources, and the processes that enable work is mostly transparent to the workers. They center their attention on performing work. However, a noticeable change in the work conditions, in the required quality of the product, or in the perceived results of work, may be experienced as a breakdown that brings teamwork to the center of attention. To deal with breakdowns it is currently common practice to include tailoring facilities in groupware systems. The extent to which these facilities are provided, and the way in which they are implemented, determine the power users have to change the groupware system. Determining these facilities has been the focus of most research on tailorability in CSCW. How collaborative tailoring (defined as, collaboration for and in tailoring) can be facilitated remains as yet undetermined. This thesis tackles the problem of the lack of computer support for dis- tributed team members that need to perform tailoring in the context of team- work. The challenge of tailoring in the context of teamwork is to understand and support the needs of the group members, from the moment they encounter a breakdown during work until they have enacted the changes they deem nec- essary. This thesis is based on the premise of participation as a means to achieve acceptance of change. The approach to support collaborative tailoring of team- work presented in this thesis consists of a method for collaborative breakdown handling, a selection of specific groupware tools to be used for the deliberation activities defined by the method, and guidance in the form of scaffoldings for the application of the method. Breakdowns can also occur during tailoring. To deal with breakdowns that occur during tailoring, the method, the tools, and the scaffolding can be tailored. The proposed support for collaborative tailor- ing of teamwork is delivered as a stand-alone groupware system for collaborative tailoring. The system can be deployed along existing groupware systems, thus extending them with support for collaborative tailoring. This thesis exceeds related work by approaching tailoring of teamwork as a social system with a model that explains tailoring as the result of collaborative breakdown handling. The requirements of communication, collaboration, co- operation and coordination, and negotiation observed in the social system are supported by the corresponding technical system. The approach in this thesis is not limited to its application in a particular scenario or groupware system. The only requirement is that the target system/scenario can be tailored. The approach has been conceived to enable and support its own evolution as the result of its tailoring.

Analyzing prediction market trading behaviour to select Delphi-experts

foresight ◽  
2018 ◽  
Vol 20 (4) ◽  
pp. 364-374 ◽  
Author(s):  
Simon Kloker ◽  
Frederik Klatt ◽  
Jan Höffer ◽  
Christof Weinhardt
Keyword(s):  
Delphi Study ◽  
Trading Volume ◽  
Prediction Market ◽  
Content Type ◽  
Informed Traders ◽  
The Moment ◽  
Delphi Studies ◽  
Selection Of ◽  
Trading Behaviour

Purpose The selection of experts for Delphi studies is crucial for the quality of the forecast results and the information taken into account. In the past, this has usually been done by selecting participants according to their reputation, although this approach is questionable in terms of reaching the most knowledgeable participants having new, relevant and valid information. In this context, this paper aims to propose to operate a prediction market alongside Delphi studies and select participants based on their trading behaviour in the market for the Delphi study. Design/methodology/approach Based on more than three years of historical prediction market trading data, the authors verify attributes that indicate insightful trades, as previously discussed in the finance literature, by using regression and classification trees. Findings The paper contributes attributes of trading behaviour that are theoretically derived from literature and potentially related to informed traders. These are tested and evaluated on historical prediction market data. Especially, the trading volume, the spread at the moment of trading and the market maker attribute seem to predict informed traders the best. Originality/value Algorithms based on identified attributes can be used to objectify the selection of experts for Delphi studies with potential gains in terms of the amount of information considered.

Development of e-сommerce logistics

2019 ◽  
pp. 95-100
Author(s):  
E. A. Torgunakov ◽  
E. V. Torgunakova
Keyword(s):  
Full Range ◽  
Sales Promotion ◽  
Online Store ◽  
Scientific Methods ◽  
General Scientific ◽  
Online Stores ◽  
Basic Approaches ◽  
The Moment ◽  
Selection Of

In the competitive, rapidly developing e-commerce market, most of the costs of organizations are associated with logistics and sales promotion. Implementation of fulfillment, i.e. the full range of services provided to e-commerce companies by a universal logistics operator, reduces the costs of goods delivery while ensuring the safety of goods and high quality of service.Aim. The presented study aims to examine and develop methods for improving the logistics processes of companies operating in the e-commerce market.Tasks. The authors examine the specific features and trends on the Russian e-commerce market, analyze the existing methods of delivering goods from online stores to the end consumer, and substantiate the need to apply modern methods of goods delivery.Methods. This study uses general scientific methods of cognition to examine the logistics processes of e-commerce and formulate basic approaches to improving the logistics of online stores.Results. The statistics of the Russian e-commerce market is analyzed. The specific features of logistics in e-commerce and methods of goods delivery are determined. Different types of logistics operators acting in the e-commerce market are examined. The benefits and drawbacks of fulfillment – the full range of services provided to e-commerce companies by a universal logistics operator from the moment a customer places an order to the moment they receive the goods – are identified. It is established that fulfillment for an online store includes the acceptance nad storage of goods, correspondence, and other types of cargo at a specially equipped warehouse, proper packaging of goods that are to be shipped to the consumer, and selection of an optimal delivery scheme depending on urgency and other factors. The necessity of implementing this delivery technology in the operation of an online store is substantiated.Conclusions. Improvement of the methods of goods delivery to the consumers of online stores can reduce logistics costs while providing quality service.

scholarly journals Myśli Jana Jakuba Rousseau o wychowaniu i muzyce – ich reminiscencje w rytmice Emila Jaques-Dalcroze’a

2015 ◽  
Vol 30 (3) ◽  
pp. 87-103
Author(s):  
Ewa Szatan
Keyword(s):  
Music Education ◽  
Learning Process ◽  
Musical Education ◽  
The Moment ◽  
The One ◽  
Selection Of

The text is an attempt to analyze and interpret a selection of Jean-Jacques Rousseau’s thoughts about education relating to music education, the thoughts that I find as reminiscences of assumptions and methods of Emil Jaques-Dalcroze. He focuses his discourse on the issues related to the moment when the musical education of the child takes form and also on the quality of the child’s first contacts with music, and the role of parent and teacher in the child’s appreciation of music. A comparison of the assumptions regarding musical education of Rousseau and Jaques-Dalcroze may seem interesting, because, despite the passage of successive decades, they seem to be still valid, as, for example, the one that speaks of the joy of discovery that should accompany the child in the learning process.

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