scholarly journals Experience and scientific research to substantiate the performance of work in construction

2020 ◽  
pp. 71-79
Author(s):  
I. E. Shatrova ◽  
E. A. Demidova
Keyword(s):  
Market Economy ◽  
Negative Impact ◽  
Residential Buildings ◽  
Practical Importance ◽  
Optimal Level ◽  
Housing Construction ◽  
Construction Work ◽  
Actual Duration ◽  
Probabilistic Nature

The article provides an analysis of the timeliness of work in construction and experience and research to justify the duration of work in construction. Experience shows that in construction, including housing construction, there is a significant deviation of the actual duration of work from the projected one, which leads to untimely commissioning of residential buildings. Increasing the reliability of justifying the duration of work in construction in conditions of the probabilistic nature of construction production, as experience and research shows, can be carried out on the basis of time reservation to compensate for the negative impact of the micro- and macroenvironment. At the same time, as experience shows, the determination of the duration of construction and installation works, in most cases, is carried out using deterministic methods focused on the use of established standards without taking into account the influence of random factors due to the probabilistic nature of construction production. Other methods, which in one way or another take into account the probabilistic nature of construction production, do not provide an opportunity, when justifying the duration of housing construction work, to determine the optimal level of time reservation required to eliminate the consequences of a negative impact on the progress of work from a large number of random factors. Thus, the development of a scientifically based methodological basis for optimizing the duration of housing construction and a market economy is an urgent problem of scientific and practical importance. Determination of the optimal duration of housing construction work is based on theoretical and methodological systemic principles, which make it possible to determine the optimal level of time reservation and study its dependence on individual organizational and technological factors, taking into account the specifics of construction production and the conditions of a market economy.

DEFINITION OF TIME SPENT ON REPAIR OF BUS TRANSMISSION UNITS TAKING INTO ACCOUNT TECHNOLOGICAL EQUIPMENT RELIABILITY

2020 ◽  
Vol 2020 (9) ◽  
pp. 29-33
Author(s):  
Sergey Bulatov
Keyword(s):  
Negative Impact ◽  
Probabilistic Method ◽  
Technological Equipment ◽  
Quality And Safety ◽  
Transmission Unit ◽  
Equipment Reliability ◽  
Hours Of Work ◽  
Definition Of ◽  
Time Decrease

The paper purpose is the effectiveness estimation in the technological equipment use, taking into account its reliability and productivity for defective transmission units of buses. The problem consists in the determination of time to be spent on repair of bus transmission units taking into account technological equipment reliability. In the paper there is used a probabilistic method for the prediction bus transmission units, and also a method of the dynamics of averages which allow ensuring minimum of costs for units downtime during repair and equipment cost. The need for repair of transmission units (gear box) arises on an average after 650 hours, the average productivity of the bench makes 4.2 bus / hour. The bench fails on the average after 4600 hours of work, the average time of the bench makes 2 hours. In such a way the solution of the problem specified allows analyzing the necessity of time decrease for transmission unit repair to avoid long downtimes of buses in repair areas without negative impact upon high repair quality and safety during the further operation.

Laboratory Researches of Resistance to a Heat Transfer of an Easy Protecting Design

2014 ◽  
Vol 635-637 ◽  
pp. 60-64
Author(s):  
Daria Vladimirovna Petrosova ◽  
Dmitri Vadimovich Petrosov ◽  
Natalia Mikhailovna Kuzmenko
Keyword(s):  
Heat Transfer ◽  
Residential Buildings ◽  
Initial Experience

Now in Russia construction of buildings with framework use from a metalwork which show itself as universal, strong, easy and fast-built is actively conducted. There are offers and initial experience of application of easy steel protecting designs with an effective heater in multystoried frame residential buildings, but without sufficient theoretical and experimental justification.In this regard, the question of determination of the heatphysical properties, in particular the specified resistance to a heat transfer, is actual.Results of laboratory researches of the specified resistance are presented to a heat transfer of an easy protecting design in article.

scholarly journals Assessing Architecture-and-Landscape Integration as a Basis for Evaluating the Impact of Construction Projects on the Cultural Landscape of Tourist Seaside Resorts

Land ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Wojciech Bal ◽  
Magdalena Czalczynska-Podolska
Keyword(s):  
Construction Projects ◽  
Cultural Landscape ◽  
Negative Impact ◽  
Residential Buildings ◽  
Evaluation Criteria ◽  
Development Project ◽  
Clear Trend ◽  
Original Culture ◽  
Construction Plans ◽  
The Impact

The coastline of Western Pomerania has natural and cultural assets that have promoted the development of tourism, but also require additional measures to ensure the traditional features and characteristics are protected. This is to ensure that new developments conform to a more uniform set of spatial structures which are in line with the original culture. Today, seaside resorts are characterized by a rapid increase in development with a clear trend towards non-physiognomic architectural forms which continually expand and encroach on land closer to the coastline. This results in a blurring of the original concepts that characterized the founding seaside resort. This study evaluates 11 development projects (including a range of hotels, luxury residential buildings and hotel suites) built in 2009–2020 in the coastal area of Western Pomerania. An assessment of architecture-and-landscape integration for each development project was made, using four groups of evaluation criteria: aesthetic, socio-cultural, functional and locational factors. The study methodology included a historical and interpretative study (iconology, iconography, historiography) and an examination of architecture-and-landscape integration using a pre-prepared evaluation form. Each criterion was first assessed using both field surveys and desk research (including the analysis of construction plans and developer materials), and then compared with the original, traditional qualities of the town. This study demonstrates that it is possible to clearly identify the potential negative impact of tourism development on the cultural landscape of seaside resorts, and provides recommendations for future shaping, management and conservation of the landscape.

scholarly journals Potentiometric Surfactant Sensor Based on 1,3-Dihexadecyl-1H-benzo[d]imidazol-3-ium for Anionic Surfactants in Detergents and Household Care Products

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3627
Author(s):  
Nikola Sakač ◽  
Dubravka Madunić-Čačić ◽  
Dean Marković ◽  
Lucija Hok ◽  
Robert Vianello ◽  
...  
Keyword(s):  
Anionic Surfactants ◽  
Negative Impact ◽  
Ion Pair ◽  
Two Phase ◽  
Potentiometric Response ◽  
Titration Curves ◽  
Signal Change ◽  
Nernstian Slope ◽  
Good Agreement

A 1,3-dihexadecyl-1H-benzo[d]imidazol-3-ium-tetraphenylborate (DHBI-TPB) ion-pair implemented in DHBI-TPB surfactant sensor was used for the potentiometric quantification of anionic surfactants in detergents and commercial household care products. The DHBI-TPB ion-pair was characterized by FTIR spectroscopy and computational analysis which revealed a crucial contribution of the C–H∙∙∙π contacts for the optimal complex formation. The DHBI-TPB sensor potentiometric response showed excellent analytical properties and Nernstian slope for SDS (60.1 mV/decade) with LOD 3.2 × 10−7 M; and DBS (58.4 mV/decade) with LOD 6.1 × 10−7 M was obtained. The sensor possesses exceptional resistance to different organic and inorganic interferences in broad pH (2–10) range. DMIC used as a titrant demonstrated superior analytical performances for potentiometric titrations of SDS, compared to other tested cationic surfactants (DMIC > CTAB > CPC > Hyamine 1622). The combination of DHBI-TPB sensor and DMIC was successfully employed to perform titrations of the highly soluble alkane sulfonate homologues. Nonionic surfactants (increased concentration and number of EO groups) had a negative impact on anionic surfactant titration curves and a signal change. The DHBI-TPB sensor was effectively employed for the determination of technical grade anionic surfactants presenting the recoveries from 99.5 to 101.3%. The sensor was applied on twelve powered samples as well as liquid-gel and handwashing home care detergents containing anionic surfactants. The obtained results showed good agreement compared to the outcomes measured by ISE surfactant sensor and a two-phase titration method. The developed DHBI-TPB surfactant sensor could be used for quality control in industry and has great potential in environmental monitoring.

THE CONCEPT, TYPES, TASKS AND THE NEED FOR THE USE OF URGENT INVESTMENT TOOLS OF CRISIS MANAGEMENT AT ENTERPRISES

2017 ◽  
Author(s):  
Oksana Yurynets ◽  
Keyword(s):  
Crisis Management ◽  
Economic Condition ◽  
Negative Impact ◽  
Negative Influence ◽  
Management Program ◽  
Management Tools ◽  
The Subject ◽  
Effective Development ◽  
Selection Of

Currently, many Ukrainian enterprises are in crisis. Getting out of this situation requires the use of various types of urgent crisis management tools, among which investment instruments play an important role. The purpose of this article is to form the theoretical basis for the use of urgent investment tools of crisis management at enterprises. It was found that the urgent investment tools of crisis management in the enterprise should be understood as ways of immediate (urgent) investment actions which are aimed at eliminating or reducing the negative impact of the crisis on the economic condition of the enterprise and ensuring its further effective development. These instruments are grouped according to the following characteristics: the environment in which the relevant instruments are formed and operate, the relation to the current owners of the enterprise, the effectiveness of implementation, the duration of the effect of implementing instruments, the urgency of their implementation, the areas of investment, the objectives of application, the duration of application, the types of financial and economic crises at the enterprise, the elimination (reduction) of the negative influence of which the corresponding tools are directed at, the subject of investment. It is established that the main tasks of using investment urgent tools of anti-crisis management at the enterprises are: selection of the best types of investment urgent tools of anti-crisis management; selection of the best variant of each type of urgent investment tools of crisis management; setting deadlines for the implementation of selected types and options for urgent tools of crisis management at the enterprise; determination of the optimal amount of total investments that should be invested in the implementation of the crisis management program at the enterprise, and the corresponding to this volume of the general list of investment urgent tools of such management; identifying the best sources of investment and establishing the best structure of investment in terms of these sources.

scholarly journals Redefining cost-optimal nZEB levels for new residential buildings

2019 ◽  
Vol 111 ◽  
pp. 03035 ◽  
Author(s):  
Raimo Simson ◽  
Endrik Arumägi ◽  
Kalle Kuusk ◽  
Jarek Kurnitski
Keyword(s):  
Energy Use ◽  
Net Present Value ◽  
Residential Buildings ◽  
Energy Performance ◽  
Optimal Level ◽  
Building Envelope ◽  
Simulation Software ◽  
The European Union ◽  
Apartment Building ◽  
Detached House

In the member states of the European Union (EU), nearly-Zero Energy Buildings (nZEB) are becoming mandatory building practice in 2021. It is stated, that nZEB should be cost-optimal and the energy performance levels should be re-defined after every five years. We conducted cost-optimality analyses for two detached houses, one terraced house and one apartment building in Estonia. The analysis consisted on actual construction cost data collection based on bids of variable solutions for building envelope, air tightness, windows, heat supply systems and local renewable energy production options. For energy performance analysis we used dynamic simulation software IDA-ICE. To assess cost-effectiveness, we used Net Present Value (NPV) calculations with the assessment period of 30 years. The results for cost-optimal energy performance level for detached house with heated space of ~100 m2 was 79 kWh/(m2 a), for the larger house (~200 m2) 87 kWh/(m2 a), for terraced house with heated space of ~600 m2 71 kWh/(m2 a) and for the apartment building 103 kWh/(m2 a) of primary energy including all energy use with domestic appliances. Thus, the decrease in cost-optimal level in a five-year period was ~60% for the detached house and ~40% for the apartment building, corresponding to a shift in two EPC classes.

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