bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of fuel consumption and exhaust emissions in WLTP and NEDC procedures
Authors: KOSZAŁKA Grzegorz , SZCZOTKA Andrzej , SUCHECKI Andrzej
Published: March 2021

Fuel consumption achieved in the New European Driving Cycle (NEDC) could be 50% lower than the fuel consumption in real driving conditions and in the case of emissions of regulated toxic compounds the differences could even be much greater. In order to bring the results achieved in official tests closer to real life figures, the European Commission introduced in 2017 the Worldwide Harmonized Light Vehicles Test Procedure (WLTP), which replaced the NEDC. In this article the results of fuel consumption and exhaust emissions for 3 cars fitted with engines of the same displacement but with direct and indirect gasoline injection, determined according to the NEDC and WLTC were presented. The results show that the effect of driving cycle on the fuel consumption is equivocal – for one car, fuel consumption was higher in the WLTC; for the other one in the NEDC; and for the third one, fuel consumption achieved in both driving cycles was practically the same. Emissions of regulated exhaust compounds, except for THC, obtained in the WLTC were higher than in the NEDC driving cycle.
The influence of cetane-detergent additives into diesel fuel increased to 10% (V/V) of RME content on energy parameters and exhaust gas composition of a diesel engine
Authors: STANIK Winicjusz , CISEK Jerzy
Published: March 2021

To avoid the negative effects of increasing the amount of RME in the diesel fuel (to 10%), three different additive packages were used: stabilising, cleaning, and increasing the cetane number with different concentrations. The tests were carried out using a 4-cylinder, turbocharged 1.9 TDI engine from VW. The tests were carried out for 4 fuels (comparative fuel with a content of 7% RME and 3 test fuels with a content of 10% RME, differing in the content of the additive package.It was found that each of the 3 additive packages used does not have a significant impact on fuel consumption. However, a different effect of the tested additives on the composition of exhaust gases was observed. The first package had a slight effect on reducing the NOx concentration in the exhaust, but only for small engine loads. On the other hand, the second additive pack worked more effectively only at higher engine loads (in relation to the reduction of NOx concentration in the exhaust gases). In the third packet, the amount of the cetane additive was doubled (compared to the second packet). Then, the reduction in the NOx concentration in the exhaust gas by 3–8% was obtained with reference to the comparative fuel.
Performance analysis of turbofan engine with additional combustion chamber fueled by alternative fuel
Authors: MARSZAŁEK Natalia
Published: March 2021

Presented paper is focused on the performance analysis of turbofan engine with additional combustion chamber fueled by alternative fuel. Additional combustion chamber was situated between high pressure turbine and low pressure turbine. Such configuration is also know under the name inter turbine burner (ITB). As an alternative fuels burn in additional combustion chamber were selected cryogenics fuels: liquid hydrogen and liquid methane. The main combustion chamber was supplied by conventional aviation fuel - kerosene. Thermodynamic model of turbofan engine with ITB was implemented in MATLAB environment. The problem of modeling an additional combustion chamber was presented.Analysis was carried out for take-off conditions. Obtained results indicate that implementation of ITB exert a positive influence on engine performance result in thrust increase.
Impact of the use of comfort devices on the exhaust emission from a hybrid vehicle
Authors: SIEDLECKI Maciej , MERKISZ Jerzy , KUBIAK Kamil , RYMANIAK Łukasz , DOBRZYŃSKI Michał , GALLAS Dawid
Published: March 2021

Vehicles are equipped with more and more devices to improve the comfort of traveling. They are usually powered by electricity generated by the engine, which translates into an increase in its loads and, as a consequence, fuel consumption and emission. However, there is no information about the possible increase in the amount of other harmful components contained in the exhaust gases. Often this result is inadequate to that obtained during the operation of the vehicle, where the obtained fuel consumption is higher. As part of this article, tests were carried out in real hybrid vehicle traffic conditions on the same test route using an analyzer from the PEMS (Portable Emission Measurement System) ¬ SEMTECH DS Sensors Inc. The analysis of gaseous components of exhaust gases together with the exhaust mass flow probe and the GPS system made it possible to calculate the pollutant emission.. On this basis, the actual mileage fuel consumption of the tested vehicle was calculated using the road emission of carbon-containing compounds (carbon balance method).
Environmental assessment of the exploitation of diesel engines powered by biofuels
Authors: GRZELAK Paulina , ŻÓŁTOWSKI Andrzej
Published: March 2021

Many factors, such as climate change and the associated risk of increasing the average temperature on the globe, energy security and the finishing of fossil fuel deposits have caused other renewable energy sources to be sought. Transport, as a branch of industry largely responsible for air pollution and greenhouse gas emissions in large cities, requires the necessary changes in the way vehicles are powered. Until now, the fuels available at petrol stations use admixtures of first generation biofuels, such as bioethanol, as a 5% additive to motor gasolines and biodiesel (FAME) as a 7% additive to diesel oil.
The article presents the idea of biorefinery installations, specifies the spectrum of substrates of the second and advanced generations, which may be a biorefinery input, including waste oils that can be used to produce hydrogenated HVO vegetable oils and other high-value products. The paper presents he existing biorefinery plant in Venice resulting from the transformation of a conventional oil refinery in which HVO fuel is produced. The article also presents the parameters of this new biofuel and compared them with the parameters of other fuels used to power self-ignition engines, such as FAME and diesel, along with discussing the prospects for HVO fuel development in Europe.
Diagnostic and reliability model of an internal combustion engine
Authors: ORCZYK Małgorzata , TOMASZEWSKI Franciszek
Published: March 2021

The article presents a diagnostic and reliability model of an internal combustion engine that allows to assess the reliability status of the engine’s systems for a two-state model of operation and maintenance: functional – failed. The proposed diagnostic model is a qualitative-quantitative probabilistic model combining the reliability states of the engine systems with the values of the vibroacoustic diagnostic signal parameters. The conducted diagnostic and reliability experiments and simulation tests showed that based on the developed diagnostic and reliability model, it is possible to determine the reliability states of the engine.
By-products from thermal processing of rubber waste as fuel for the internal combustion piston engine
Authors: CHWIST Mariusz , GRUCA Michał , PYRC Michał , SZWAJA Magdalena
Published: March 2021

The article presents results of investigation on the combustion of a mixture of oil from pyrolysis of tires and basic fuel in an internal combustion reciprocating piston engine. The tested fuel consisted of: diesel oil and oil from pyrolysis of tires at amount of 10% by volume. The tests were carried out on a single-cylinder naturally aspirated compression-ignition engine. The engine is equipped with a common rail fuel injection system and an electronic control unit that allows changing injection timing. A comparative analysis of pressure-volume charts for the reference fuel, which was diesel, and for a mixture of diesel with the addition of 10% oil from tire pyrolysis was carried out during the study. Injector characteristics for the reference fuel and the mixture were determined. Engine efficiency for both fuels was determined. Unrepeatability of the engine work cycles for the diesel fuel and the tested mixture was calculated. Finally, the share of toxic exhaust components in exhaust gases was analyzed. It was found that pyrolisys oil from tires can be used as additive to regular diesel fuel at amount up to 10%, however, toxic exhaust gases emission was increased.
The analysis of vibrations in the vehicle with naturally aspirated and turbocharged gasoline engine
Authors: ŁOZA Łukasz
Published: March 2021

In this paper, the author presents a study of vibrations in a passenger vehicle and the possible influence on driver’s body in the process of natural operation. The author describes the dependence of engine size and additional equipment as the possible primary source of the vibration variations and their further propagation in the entire vehicle structure. The analysis was performed on the passenger cars with naturally aspirated and turbocharged gasoline engines. The aim of this study was to verify the level of vibrations in the vehicle structure with these particular engines, especially influence of downsized power unit, during various state of engine operation. The second goal was to examine the vibrations in the specified location related to driver’s body. The measuring method used piezoelectric accelerometers, which were attached to the designated locations in the vehicle and were able to detect variations of the acceleration. The signals were collected as characteristics in the time domain. In order to achieve frequency domain for spectral analyses, the author applied the Fast Fourier Transform (FFT).
Cold start emissions from a gasoline engine in RDE tests at different ambient temperatures
Authors: KURTYKA Karolina , PIELECHA Jacek
Published: March 2021

The implementation of the 3rd package of the RDE test procedure has extended the test method by considering emissions from a cold start period into the total exhaust emissions from a vehicle. The article presents the research results of exhaust emissions of a vehicle equipped with a gasoline engine. The tests were carried out at two different ambient temperatures, in line with the requirements of the RDE test procedure for passenger cars, meeting the Euro 6d-Temp emissions standard. The obtained results were analyzed, i.e. there were compared the engine and vehicle operating parameters and the values of road exhaust emissions during the cold start at two different ambient temperatures. The summary presents the shares of the cold start phase for each exhaust emission compound in the urban part of the test and the entire RDE test, depending on the ambient temperature (8ºC and 25ºC).
The impact of thermodynamics parameters of turbofan engine with ITB on its performance
Authors: Marszałek Natalia
Published: March 2021

Presented paper is focused on the influence of additional combustor chamber named inter turbine burner on turbofan engine unit parameters. Investigation has been made how changing selected engine parameters affect its performance. A comparison has been made between the baseline turbofan engine and the engine with ITB. Engine thermodynamics model was prepared in MATLAB software. Main combustion chamber was fueled by kerosene, commmonly used in aviation transport, while inter turbine burner by alternative fuel. As an alternative fuel were choose liquid hydrogen and methane. Numerical researches were carried out for take-off conditions. Engine specific thrust and specific fuel consumption were obtained as a function of bypass ratio, turbine inlet temperature, fan pressure ratio, HPC and LPC pressure ratio. The results of the study indicate that hybrid engine with additional combustion chamber fueled by hydrogen fuel is more efficient than other studied cases.
The possibility of energy consumption reduction using the ECO driving mode based on the RDC test
Authors: Cieślik Wojciech , Szwajca Filip , Golimowski Jacek
Published: March 2021

The greenhouse effect and overall climate changes are the main reasons for developing ecological powertrain units dedicated to road vehicles. An electrical drivetrain without using conventional combustion engines fueled by hydrocar-bon fuels is an effective method to significantly reduce CO2 emissions from the fleet. It is particularly vital in 2020 emis-sion regulations aspects, and continuously the number of vehicles increasing. In this paper battery electric drive system of a small size passenger car was analyzed in terms of two different drive modes in cooperation with two recuperative braking modes. The research was carried out with real driving condition test requirements and driving parameters re-cording. Based on data obtained from OBD signals, energy flow and torque distribution have been specified. In results, overall reducing energy consumption has been achieved with ECO mode compared to normal mode. Selection of the driving mode ECO has a positive impact on reducing the state of charge saving more than 5%, taking into account the whole RDC test; greater energy consumption reductions were observed in selected test areas.
Evaluation efficiency of low-power fans used in the means of transport
Authors: Nygard Adam , Bartoszewicz Jarosław
Published: March 2021

The article presents test results on low-power fans used in the means of transport. Fans evaluation was in the context of energy efficiency. Interest in scientific topics related to low-power fans has its source in the reports of the Chief Inspector of Environmental Protection on the state of the natural environment in Poland and European Union reports assessing our natural environment. The goal of the article is to compare experimental results with Minister of Economy Regulation of March 11th, 2014, which introduces changes in accordance to European Parliament and Council Directive 2009/125/WE, with regard to ecodesign requirements for fans driven by motors with an electric input power between 125 W and 500 kW.
Non-Regulated Emissions and PN of Two Passenger Cars with Diesel-Butanol Blends
Authors: Engelmann Danilo , Comte Pierre , Czerwinski Jan , Renz Stephan , Bonsack Peter
Published: March 2021

Biofuels represent one of the alternatives to obtain the CO2-neutral propulsion of IC-engines. Butanol, which can be produced from biomass, is considered and was investigated in the last years due to the very advantageous characteristics of this alternative fuel. Butanol can be easily and irreversibly blended both with light (gasoline) and heavier (Diesel) fuels. Comparing with ethanol it has the advantages of: higher calorific value, lower hygroscopicity and lower corrosivity. It can replace the aviation fuels.
This paper presents the emission results obtained on two Diesel passenger cars with different technology (Euro2 and Euro6c) and with addition of Butanol to Diesel fuel, as a part of the research project DiBut (Diesel and Butanol). Interesting results are given about some non-legislated (non-regulated) components, Acetaldehyde (MeCHO) and Formaldehyde (HCHO) and about the PN-emissions with/without DPF.
Energy conversion in motor vehicles.
Authors: Szałek Andrzej
Published: March 2021

The portfolio of the automotive market appears more and more low-emission and zero-emission propulsions in vehicles. This is the result of measures taken to limit or even eliminate the emission of harmful substances into the atmosphere generated by vehicles. The article covers issues related to energy conversion in automotive drive systems currently offered by automotive manufacturers. Standard, hybrid, hybrid plug-in, electric and fuel cells drive system were analyzed. Attention was drawn to the chain of energy transformations related to each of the analyzed drive systems. The efficiency of the presented vehicle drive systems was analyzed. General conclusions were formulated regarding the method of analyzing energy changes related to the operation of automotive propulsion systems. The article reviews selected author's own works on hybrid and hydrogen propulsions.
Piston assembly in the most powerful 2.0l diesel engine – case study of the current tribological system and innovative concepts for the future
Authors: KAŁUŻNY Jarosław , MERKISZ Jerzy , STEPANENKO Aleksander , WRÓBLEWSKI Emil , GAPIŃSKI Bartosz , PIASECKI Adam , GALLAS Dawid
Published: March 2021

This article is a contribution to the ongoing debate on the scenario of the vehicle powertrains development. The directions of the internal combustion engines development in search of the possibility of effective economic and ecological indicators improvement have been indicated. It has been pointed out that this goal can be achieved through the use of nanotechnology in order to exceed the downsizing barriers resulting from the permissible mechanical loads for conventional materials. The article presents the study of the construction and materials used in the piston assembly of the most advanced four-cylinder, compression-ignition diesel engine currently in manufacture. Original concepts of nanotechnology have been proposed to reduce friction losses in major friction components of future engines with extremely high loads. The main idea is to verify the hypothesis that the sub-micron surface texture of the friction components obtained in the process of applying anti-wear outer layers can lead to an effective reduction of friction losses under real engine operating conditions. Computer simulations of the effects of introducing the surface texture in the upper sealing ring on friction loss confirm this hypothesis by showing friction value being reduced by 3-4% relative to the standard ring profile. In the summary, further advanced technologies designed to effectively utilize the unique properties of carbon nanotubes have been described.
Bio-ketones from lignocellulosic biomass: experimental investigation on fuel properties, combustion and emissions characteristics of cyclopentanone blend with diesel in compression ignition engine
Authors: DOUSTDAR Omid , WYSZYNSKI Miroslaw Lech , TSOLAKIS Athanasios , MAHMOUDI Hamid
Published: March 2021

Use of alternative fuels in compression ignition engines is the topic for many studies. This paper presents the results of lubricity, calorific value, viscosity, surface tension and density of a ketone blend with diesel to use as a fuel in compression ignition engine. Analyses of fuel properties are vital due to their effect on fuel system. In addition, this study is related to the development of future biofuels and it indicates the effect of oxygen double bond in molecular structure of ketones on important fuel properties. Cyclopentanone which has cyclic molecular structure was used; it can be produced from lignocellulosic biomass through various processing ways. This ketone was blended with diesel fuel at 10% vol. Results from fuel properties tests were compared to the conventional diesel fuel. In the next step this blend was tested in a research diesel engine to analyse its combustion behaviour and emission characteristics of exhaust gases; these results were compared with ultra-low sulphur diesel fuel. Results showed that cyclopentanone, as an additive to diesel, improved surface tension and density of the fuel but in contrast had negative effect on viscosity, lubricity and calorific value of the fuel, but still in the standard range. Combustion behaviour of this fuel in the diesel engine also showed longer ignition delay of ketone blend and also that gaseous emission such as CO and THC are higher than from diesel fuel and NOx emission is less than from conventional diesel fuel combustion.
NILAI TOLERANSI DALAM NOVEL “AYAT-AYAT CINTA 2” KARYA HABIBURRAHMAN EL-SHIRAZY
Authors: Kahfi Muhammad Rajul
Published: March 2021

Penelitian ini dilatar belakangi oleh kepopuleran Novel Ayat-ayat Cinta 2 karya Habiburrahman El-Sirazhy yang menggambarkan harmonisasi antarumat beragama. Ayat-ayat Cinta 2 karya Habiburrahman El-Sirazhy merupakan salah satu karya sastra yang bersifat kompleks, unik dan tidak langsung dalam pengungkapannya masih memerlukan penjelasan yang tepat agar memberikan pemahaman yang sesuai tentang toleransi dan klasifikasinya. Penelitian dilakukan dengan metode deskripsi kualitatif terhadap Novel Aya-ayat Cinta 2 karya Habiburrahman El-Shirazhy dengan mendokumentasikan data yang terdapat dalam novel, mengolah data, dan menyusun hasil identifikasi serta menyimpulkan hasil data yang dianalisis secara keseluruhan dalam bentuk tulisan. Hasil penelitian diuraikan dengan memandang nilai-nilai toleransi pada Novel Ayat-ayat Cinta 2 karya  Habiburrahman El-Shirazy sesuai dengan klasifikasi toleransi yaitu: kultural, suku, jenis kelamin, agama, dan sebagainya berdasarkan UUD 1945.
NILAI KEAGAMAAN DALAM NOVEL “TITIAN NABI” KARYA MUHAMMAD MASYKUR A.R. SAID
Authors: Hidayah Nur
Published: March 2021

Novel Titian Nabi karya Muhammad Masykur A.R. Said sarat akan nilai-nilai keagamaan. Penelitian tentang nilai dalam karya sastra, khususnya novel Titian Nabi sangat penting dilakukan untuk mengetahui hubungan karya sastra dengan kehidupan masyarakat berkaitan dengan nilai keagamaan. Masalah dalam penelitian ini adalah bagaimana pengarang mendeskripsikan nilai-nilai keagamaan yang terdapat dalam novel Titian Nabi karya Muhammad Masykur AR Said. Penelitian ini bertujuan untuk mendeskripsikan nilai-nilai keagamaan yang terdapat dalam novel Titian Nabi karya Muhammad Masykur AR Said.
KEMAMPUAN MEMBACA KRITIS PESERTA DIDIK KELAS VIII SMP NEGERI 15 BANJARMASIN
Authors: Sapiah  , Jumadi  , Taqwiem Ahsani
Published: March 2021

Tujuan penelitian,  mendeskripsikan kemampuan, (a) mengingat dan mengenali fakta tersurat isi bacaan, (b) menginterpretasikan makna tersirat isi bacaan, (c) mengaplikasikan konsep isi bacaan, (d) menganalisis isi bacaan, (e) menyintesis isi bacaan, (f) menilai isi bacaan, dan (g) membaca kritis secara komprehensif peserta didik kelas VIII SMP Negeri 15 Banjarmasin. Jenis penelitian ini adalah penelitian kuantitatif dengan metode deskriptif. Pengambilan sampel menggunakan teknik sampling sederhana. Pangambilan sampel 25% dari pupolasi, yakni sebanyak 52 orang. Teknik pengumpulan data melalui tes.Teknik analisis data dilakukan dengan beberapa tahapan. Berdasarkan  analisis hasil penelitian, yaitu kemampuan (a) mengingat dan mengenali fakta tersurat kategori baik, dengan nilai rata-rata 66,15. (b) menginterpretasikan makna tersirat kategori cukup, dengan nilai  rata-rata 65. (c) mengaplikasikan konsep dikategorikan baik, dengan nilai rata-rata 66,53. (d) menganalisis dikategorikan baik, dengan nilai rata-rata 72,5. (e) menyintesis dikategorikan baik, dengan nilai rata-rata 75,19. (f)  menilai isi bacaan, dikategorikan cukup, dengan nilai rata-rata 62,5. Untuk kemampuan membaca kritis secara komprehensif dikategorian baik, dengan nilai rata-rata 70,10.
Effects of the Covid-19 Pandemic Estimated in the Financial Statements and the Auditor`s Report
Authors:   West University Timisoara, Romania, CRUCEAN Andreea Claudia , HATEGAN Camelia-Daniela ,   West University of Timisoara, Romania
Published: March 2021

The COVID-19 pandemic had a significant impact on all aspects of life, but also on the financial reporting of companies and on the activity of auditors. The paper aims to highlight the importance of reporting in the financial statements the subsequent events caused by the COVID-19 pandemic, but also of the aspects that can significantly influence the going concern of companies' activities, respectively how these effects can cause changes in the quality of audit services. The study was conducted on a sample of 60 companies listed on the Bucharest Stock Exchange, analyzing the components of the annual reports for the financial year 2019, namely the financial statements, the administrator's report and the independent auditor's report. The results showed that the effects generated by the COVID-19 pandemic had a significant impact in most of the industries studied, affecting both companies to carry out activities by closing borders, reducing or even closing certain activities, stopping travel and hindering communication with suppliers, customers or investors, reduced sales, deferred payments or the need to optimally manage costs and available resources, as well as at the level of employees by performing work at home, technical unemployment or salary reductions, but also at the level of the client-auditor relationship, by limiting travel in business interest. Most of the estimated effects of the pandemic were presented in the administrator's report, some of the effects being mentioned in the explanatory notes to the financial statements. From a statistical point of view, the companies' declaration of the effects of the pandemic was correlated with the size of the auditor, the opinion issued by him and the average number of employees. The study showed that certain auditors assessed the risks posed by subsequent events reported by companies, presenting insignificant uncertainties in some cases, but also significant uncertainties regarding the going concern of the activity of some companies.
Considerations Regarding Correlated Analysis between Comply or Explain Declaration and Non-Financial Reports
Authors:   The Bucharest University of Economic Studies, Romania, CARATAS Maria Alina , STANCIU Victoria ,   The Bucharest University of Economic Studies, Romania
Published: March 2021

Corporate governance still remains a topic of great interest to both researchers and practitioners, as a result of the on-going challenges that companies face. The current economic and pandemic context and the need for a sustainable development bring new requirements to the governance, imposing a rethinking of strategy and business processes. The new challenges require consolidated implementations of corporate governance. The purpose of this study is to analyze how the companies’ alignment to the governance requirements is reflected in “comply or explain” declarations as well as in the non-financial reports and emphasize some identified vulnerabilities, most of them being determined by the obvious limitation of transparency and the attempt of minimizing the importance of some nonconformities. The objective of the study is to identify the barriers occurred in a solid corporate governance implementation and sustainable development of companies, as these aspects are emphasized in the reports of companies from various industries listed on Bucharest Stock Exchange. The companies’ governance consolidation process, on all its pillars, encompasses the social responsibility coordinate, and remains for the Romanian companies a process that must be accelerated and assumed entirely. The conclusions of this study offer important reflection points and might represent a solid basis for improvement of corporate governance and implicitly of stakeholders' benefits.
A Measure of Tax Burden for the Companies Listed on the AeRo Segment of the Bucharest Stock Exchange
Authors:   Alexandru Ioan Cuza” University of Iasi, Romania, ISTRATE Costel
Published: March 2021

Tax pressure can be calculated at the macroeconomic level, but also at the microeconomic level, by analysing the data provided by companies in their financial statements, or by authorities giving official statistics. In this study, the authors adapt a formula for the calculation of the effective tax rate, proposing, at the denominator, the taxes reported explicitly by companies in their profits and loss account, to which they added the reconstituted value of social and fiscal contributions of the employees. Also, unlike the literature so far, they divided these tax expenses to the sales (revenues) and not to any other indicators from the profit and loss account. The population analysed is represented by the companies listed on the AeRo market of BSE, in the period 2010- 2019, a total of almost 3,000 observations. The results allowed them to notice a systematic increase in the share of the tax burden in sales, over the period taken into account. In verifying the effects of some variables proposed by the literature on the tax burden, the authors found that large firms have a lower tax burden, more profitable firms are more taxed than others, the tax burden is lower for more leveraged firms, and increasing the share of fixed assets in the balance sheet leads to an increase in the tax burden. In addition to the literature, they introduced a new variable - audit opinion - and found out that firms that receive modified audit opinions have a higher tax burden.
Fair Value Complexity and the Audit Risk
Authors:   Babes-Bolyai University in Cluj-Napoca, Romania, DEACONU Adela , CIURDAS Ioana ,   Babes-Bolyai University, Cluj-Napoca, Romania, BONACI Carmen Giorgiana ,   Babes-Bolyai University, Cluj-Napoca, Romania
Published: March 2021

This paper checks if the auditors in an emergent context, where the fair value (FV) concept, its implementation and audit are relatively new, are aware of the estimation risk induced by the valuation process (the FV provider and FV disclosure), depending on the quality of internal control (IC). An experiment was applied to a group of auditors and master students, using two elements pertaining to FV reporting: “Valuation attributes and sensitivity of data”, respectively “Methods, assumptions and model”. This experiment revealed that: (1) FV audit risk is lower when the estimation is made by an external, instead of an internal valuator; (2) the master’s students, compared to more experienced professional auditors, manifest an overconfidence in the external Valuation Report in terms of valuation attributes, data availability and solutions adopted to test the sensitivity of value; (3) the audit risk is lower when the valuator is external and hence the auditors verify in detail the information provided in the Valuation Report as inputs and methods applied; (4) when IC is strong as quality, the verification of methods, assumptions and model induces for auditors a higher risk than the other FV disclosed component, valuation attributes and sensitivity of data, in the case of management estimation.
Reducing SO2 content in wine by combining High Pressure and glutathione addition
Authors: Christofi Stefania , Katsaros George , Mallouchos Athanasios , Cotea Valeriu , Kallithraka Stamatina
Published: March 2021

The aim of this work was to examine the potential of High Pressure (HP) technology as an alternative technique to SO2 addition for red wine preservation. It focused on producing wines with reduced added SO2 and the simultaneous addition of glutathione (GSH) as a natural antioxidant. Selected quality parameters of red wine samples from Mouchtaro grapes treated by HP using various pressure parameters were tested. HP processing studied was applied at 200, 400 and 600 MPa for 0, 5 and 15 min. The application of HP for a long duration resulted in a significant reduction in phenolic compound concentrations (TP) due to both extended polymerisation and reduced volatile acidity (VA) and acetic acid concentrations (AAC), which in turn was mainly due to better antimicrobial protection. Based on the changes to the contents of all TP, VA and AAC groups, processing for 5 min at 400 MPa was selected as the optimum HP condition. Red wine samples from Mouchtaro grapes containing 0, 20, 40, 60, 80 and 100 mg/L of SO2 and 10 mg/L of GSH were HP-treated under the selected pressure/time conditions. Untreated samples containing the same concentrations of SO2 and GSH were used as control samples. Indices such as AAC, Antioxidant activity (AOA), total anthocyanins, TP, mean Degree of Tannin Polymerisation (mDP) and the composition of volatiles was determined over a period of 12 months. Sensory analysis of the samples took place during the 12th month of storage. After the 12-month period, the pressurised samples with GSH showed higher content of total aldehyde/ketone and higher-alcohols, consistently lower concentrations of acetic acid, ethyl acetate and total esters, and lower VA values. Finally, based on the results obtained from the sensory analysis, untreated samples were characterised by "Red fruits" odours, whereas treated samples were distinguished by their "chocolate" aroma. These results suggest that HP could be used for the production of more "mature" wines. A reduced SO2 concentration of up to 40 or 60 mg/L may be sufficient for wine stabilisation when combining HP treatment and GSH additions, depending on grape variety.
Invariant Pseudoparallel Submanifolds of an Almost $\alpha$-Cosymplectic $(\kappa,\mu,\nu)$-Space
Authors: Atceken Mehmet
Published: March 2021

In this article, the geometry of pseudoparallel, Ricci-generalized pseudoparallel and 2-Ricci-generalized pseudoparallel invariant submanifolds of an almost $\alpha$-cosymplectic $(\kappa,\mu,\nu)$ space has been searched under the some conditions. We also give some characterizations for such submanifolds. I think that obtained new results contribute to differential geometry.
Considerations of Statistical Errors in a Study Protocol for Clinical Trials
Authors: Lee Hui Seung , Lim Chi-Yeon
Published: March 2021

Statistics are essential for clinical trials, and it is very important to have an accurate understanding of the purpose of the study and to apply the appropriate statistical design or methodology. Prior to conducting a clinical trial, the research protocol requires approval from the IRB (Institutional Review Board) or regulatory agency approval, and contains a variety of contents. The research protocol conducts clinical trials according to GCP (Good Clinical Practice) and describe clinical design and statistical methodologies for demonstrate the efficacy and safety of new drug or new medical devices using the obtained data in clinical trials. At this time, statistical design is applied for the protocol based on the primary study objective. The primary study objective is to influence the selection of primary endpoint to evaluate this, the sample size, the technique of minimizing the bias, the statistical analysis and method of testing the statistical hypothesis. However, statistical errors and contradictions are easy to find in the study protocol and the same errors are repeated many times, so in this paper we aim to avoid these errors in clinical studies and apply them correctly in clinical trials, intended to be helpful in derives scientific design, validity, and reliable results.
Organizational Culture for Infection Control and Practice of Standard Precaution in Veterans Hospital Nurses: The Mediating Effect of Self-Efficacy
Authors: Kim Yunghye , Song Yeoungsuk
Published: March 2021

Objectives: The purpose of this study was to examine the relationships between organizational culture for infection control and practice of standard precaution, and explore the mediating effect of self-efficacy in Hospital nurses. Methods: A descriptive research design was used. The subjects of this study were nurses working at the Hospital. Data collection was done using a self-report questionnaires in June 2019. Total 172 nurses participated for survey paper. IBM SPSS Statistics 21.0 was used. Results: The mean scores of organizational culture for infection control and practice of standard precaution were 56.39 and 161.76 respectively and self-efficacy was 67.52. Practice of standard precaution was positively associated with self-efficacy (r=0.53, p<0.001), and organizational culture for infection control (r=0.39, p<0.001). Self-efficacy plays a full mediation in the relationship between organizational culture for infection control and practice of standard precaution (Z=4.43, p<0.001). Conclusions: Improving self-efficacy may help in increasing practice of standard precaution.
The Predictive Factors of Medication Errors in Clinical Nurse
Authors: Kim Junekyu , Song Yeoungsuk , Suh Soon Rim
Published: March 2021

Objectives: The aim of this study was to identify predictive factors (fatigue, labor intensity, quality of sleep, and job stress) of medication errors in clinical nurses to improve patients’ safety. Methods: The participants of this study were 148 female nurses who have clinical experience for more than 1 year at K hospital and pregnant nurses among them were excluded. The data were collected from February 27th to March 20th, 2019. The measurements of medication errors, fatigue, labor intensity, quality of sleep, and job stress were used. Data were analyzed with descriptive statistics, t-test, ANOVA, Scheffé test, Pearson correlation coefficients and multiple regression analysis using IBM SPSS/WIN 23.0. Results: The predictive factors associated with nurses’ medication errors were clinical experience (β=-0.41), fatigue (β=0.31), work department emergency room (β=0.28), work department surgery ward (β=0.25), and job stress (β=0.23). The results showed that the nurses who had less clinical experience and felt more fatigue or job stress, were likely to have more medication errors. Also, the nurses who work in emergency room or surgery units, experience more medication errors. Conclusions: Clinical experience, fatigue, work area-emergency room, work area-surgery word and job stress were the main influential factors on medication errors of clinic nurse. Theses influential factors should be integrally considered in nursing management to decrease medication errors. Especially, it is needed to develop a programs that can indirectly improve clinical experience to prevent medication errors.
The Effect of Interaction between Obesity and Grip Strength on Health-Related Quality of Life in Elderly: Based on the Korea National Health and Nutrition Examination Survey (2016-2018)
Authors: Hyun Seungjae , Woo Darae , Park Sangshin
Published: March 2021

Objectives: The aim of this study is to determine interaction between obesity and grip strength in health-related quality of life (HRQOL). Methods: This study analyzed the data of 4,119 Korean men and women aged 65 years or older who participated in Korea Health and Nutrition Examination Survey, 2016-2018. Body mass index was divided into normal and obesity. Grip strength was defined as the maximum value of the measured data. Sarcopenia was considered as the average of grip strength less than 26 kg in men and 18 kg in women. HRQOL was measured based on the Euro quality of life-5 dimensions questionnaire. We conducted a linear regression analysis to examine interaction effect between obesity and grip strength, and to estimate the interaction term between obesity and sarcopenia in HRQOL. Results: We identified that obesity interacted with grip strength to affect HRQOL (p=0.022) in aged people. Obese elderly men and women were more likely to have lower HRQOL scores compared to those who had normal weight among participants with low grip strength values. However, there was no significant difference between obesity and normal weight at high grip strength (34.3 kg-52.7 kg) in HRQOL significantly (p=0.41). Moreover, we identified interaction effect between obesity and sarcopenia (p=0.019). Participants who had sarcopenia with normal weight were not different from those who were obese in HRQOL (p=0.61). Conclusions: Obesity and grip strength were associated with HRQOL. Also, those two factors were interacted to affect HRQOL. Obesity was interacted with sarcopenia to shape HRQOL. Therefore, we need to give a more attention to the elderly who were obese with low grip strength.
The Effect of Health Belief, Safety Motivation, and Safety-climate on the Performance of Taking Standard Precautions on Nursing College Students
Authors: Song Yeoungsuk , Byun So Hae , Kang Sun Yeong , Jeong Da Min , Choi Yu Jin , Jang Ji Won , Han Ye Ryeong , Lee Jung-Hoon
Published: March 2021

Objectives: This study was conducted to investigate the effect of health beliefs, safety motivations, and safety-climate on the performance of taking standard precautions of nursing college students with clinical practice experience. Methods: The subjects of this study were 173 students in the 3rd and 4th grades of nursing college located in Daegu Metropolitan City with clinical practice experience, and data were collected from September 7th to September 25th, 2020 using a structured questionnaire. Results: As a result of the study, the health belief of nursing college students was 3.60 (±0.75) points, safety motivation 22.40 (±5.33) points, safety-climate 4.79 (±1.90) points, and the performance of taking standard precautions was 3.21 (±0.63) points. Hierarchical regression analysis was performed with the presence or absence of infection management education, health belief, safety motivation, and safety-climate as independent variables to identify the factors that affect the performance of taking standard precautions. Factors affecting the performance of taking standard precautions are health belief (β=0.33, p=0.003), safety motivation (β=0.28, p=0.003), safety-climate (β=0.20, p=0.009). Conclusions: According to this study, health belief, safety motivation, and safety-climate influenced the performance of taking standard precautions. These results suggest that it is necessary to emphasize the importance of practicing standardism, motivate nursing students, and provide a safer hospital practice environment in order to improve the performance of taking standard precaution when nursing college students are in hospital practice.
Developing the Osteoporosis Risk Scorecard Model in Korean Adult Women
Authors: Park Ilsu
Published: March 2021

Objectives: The aim of the study was to develop the osteoporosis risk scorecard model in korean adult women aged over 30 years old. Methods: The participants of the study were 11,427 adult women aged over 30 years old who participated in the four years of the Korea National Health and Nutrition Examination Survey (2015-2018). The data were analyzed using Rao-Scott chi-square test and weighted multiple logistic regression analysis of complex sampling design. The osteoporosis risk scorecard model was developed by weighted multiple logistic regression using points to double the odds (PDO) method. Results: This study found that there were many major influencing factors for osteoporosis which included household income, educational level, body mass index (BMI), hypertension, stroke, rheumatoid arthritis, hypercholesterolemia, sarcopenia, menopause and age of menarche. In the scorecard results, the highest score range was observed in the order menopause, age of menarche (16-17 years old), educational level (elementary school or below), rheumatoid arthritis BMI (<18.5 kg/m2) and others, suggesting that these were the most important risk factors. Conclusions: The significance of this study is that it comprehensively grasps the causal relationship between osteoporosis and various factors in korean adult women. Also, it can be used as a useful measurement tool for women’s musculoskeletal health management in health-related organizations by scoring this relationship.
Factors Associated with Human Papillomavirus Non-vaccination: The National Health and Nutrition Survey
Authors: Kim Min-Ju , Lim Eunsun , Park Sangshin , Choi Nam-Kyong
Published: March 2021

Objectives: The purpose of this study was to investigate the human papillomavirus (HPV) vaccination proportion and the factors associated with HPV non-vaccination according to the characteristics of Americans. Methods: The 2015-2018 National Health and Nutrition Survey (NHANES) data were analyzed. The subjects aged 9 to 26 were divided into subgroups according to age and sex. Results: The meaningful variables influencing HPV vaccination included birth country, health insurance, hepatitis A vaccine, hepatitis B vaccine, routine place to go for healthcare and times receive healthcare last year. The factors associated with HPV non-vaccination were income, hepatitis A vaccine, hepatitis B vaccine and times receive healthcare last year. Conclusions: This study was based on a survey of Americans, so the factors associated with HPV non-vaccination may differ from those of Koreans.
Development Characteristics and Quantitative Prediction of Multiperiod Fractures in Superdeep Thrust-Fold Belt
Authors: Feng Jianwei , Qu Junxiao , Zhang Pengfei , Qin Feng
Published: March 2021

For a superdeep imbricated thrust-fold belt in the Kuqa depression of Tarim Basin, NW China, the structural fractures have a great impact on the tight gas reservoir productivity. In this research, structural fractures were characterized from core data and imaging logging data. Numerically, the finite element (FE) method was applied to simulate the 3-D paleotectonic stress field of the key fracture-generating period as well as the present-day stress field in the Keshen gas field. Based on previously developed geomechanical models, we further derived the models of fracture aperture and porosity under the palaeostress field. A fracture permeability model considering fracture filling degree and stress was developed based on the Fracture Seepage Theory. Finally, we obtained a series of calculation models for the present-day fracture aperture and permeability. The predictions based on these models agreed well with actual measurement results, with most of the relative errors less than 20%. The developed 3-D FE geomechanical model and fracture parameter prediction method hold great promise for characterizing fractures in other deep low-permeability reservoirs.
A New Effective Multiwalled Carbon Nanotube-Foam System for Mobility Control
Authors: Ramanathan Raja , Abdelwahab Omar , Nasr-El-Din Hisham A.
Published: March 2021

Nanoparticles have improved a surfactant's ability to create long-lasting foam. Recent studies have widely recommended the use of silica nanoparticles to enhance foam stability. This paper presents an experimental investigation of a new and highly effective alpha olefin sulfonate (AOS)–multiwalled carbon nanotube (MWCNT) system for mobility control during gas enhanced oil recovery (EOR) operations.

The new AOS–MWCNT system was evaluated for its foam stability at 150°F using a high-pressure view cell. The MWCNT was obtained as solid particles of aspect ratio up to 100 and silica nanoparticles of median size of 118 nm. The foam system was optimized for its maximum half-life by varying the concentration of the AOS and the nanotube from 0.2 to 1% and 250 to 1,000 ppm, respectively. Compatibility testing with salts was done as well. Coreflood experiments with 1.5-in.-diameter, 6-in.-long Berea sandstone cores were run to calculate the mobility reduction factor at 150°F. Nitrogen foam was injected into the core at 80% foam quality in the tertiary recovery mode, and the pressure drop across the core was measured. The formation brine had a salinity of 5 wt% sodium chloride (NaCl), and the foaming solutions were prepared with 2 wt% NaCl.

The optimal concentrations of the AOS solution and the nanotubes for maximum foam stability were determined to be 0.5% and 500 ppm, respectively. The optimized AOS–MWCNT system yielded 60% greater nitrogen foam half-life (32 minutes) than an optimized AOS–silica system at 150°F. The foam half-life of a stand-alone 0.5% AOS solution was 7 minutes. In the presence of crude oil, the foam half-life decreased for all the tested systems. Coreflood experiments at 150°F showed a significant increase in the mobility reduction factor when the new AOS–MWCNT system was used as the foamer instead of stand-alone AOS or AOS–silica system. The new foaming system was stable through the duration of the experiment, yielding foam in the effluent samples. There was no formation damage observed. Salt tolerance for the MWCNT nanofluid was higher than the silica nanofluid.

Foam needs to be stable for long periods of time to ensure effective mobility control during gas injection for EOR. This paper investigates a new highly effective AOS-multiwalled carbon nanotube system that outperforms the AOS–silica foaming systems in terms of foam stability and mobility control at 150°F.