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Abstract

The current study is dedicated to measuring vowel temporal acoustics (duration, durational difference, and durational ratio) in the medial position of mostly CVCVCV polysyllabic words in Arabic and Japanese, avoiding the asymmetries in vowel position, syllable structure, and coda consonant quantity (singleton versus geminate) observed in previous experiments. Twenty-nine (16 Arabic and 13 Japanese) participants were asked to use a carrier sentence to produce 60 polysyllabic (mainly CVCVCV) items that contrasted in vowel quantity (short versus long) and vowel quality (/a/, /i/, and /u/) at a normal speech rate. The results show that while short and long vowels are durationally distinct within a language, Japanese vowels are clearly longer than Arabic vowels, although the durational difference remains approximately the same between the two languages. The durational ratio of short-to-long vowel presents a new pattern that contrasts with that reported in earlier research. Specifically, Japanese long vowels in the medial position of polysyllabic words are twice as long as their short counterparts, while Arabic long vowels are more than twice as long. This shows that both vowel position and syllable structure must be considered when measuring vowel temporal acoustics or when structuring stimuli for perception experiments.
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Authors and Affiliations

Yahya Aldholmi
1

  1. Department of Linguistics and Translation Studies, King Saud University, Riyadh, Saudi Arabia
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Abstract

The basic element of a project organizing construction works is a schedule. The preparation of the data necessary to specify the timings of the construction completion as indicated in the schedule involves information that is uncertain and hard to quantify. The article presents the methods of building a schedule which includes a fuzzy amount of labour, time standards and number of workers. The proposed procedure allows determining the real deadline for project completion, taking into account variable factors affecting the duration of the individual works.

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Authors and Affiliations

E. Plebankiewicz
P. Karcińska
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Abstract

Lateritic nickel ore is used for producing of ferronickel. Nickel grade in ferronickel ranged from 20–40%. Ferronickel is commonly used to manufacture stainless steel. A new method that can increase the levels of nickel grade is selective reduction, which is a process to reduce the metal oxide to the metallic phase with the addition of additives. In this work, the selective reduction of limonitic nickel ore was carried out by add the 5 wt%, 10 wt%, and 15 wt% of reductant and the 10 wt% of sulfur as additive. The process of selective reduction is performed at temperatures of 950, 1050, and 1150°C with the duration of processs of 60, 90, and 120 minutes, followed by magnetic separation to separate between the concentrate and tailings. The characterization used AAS, XRD, and SEM-EDS for grade and recovery; phases transformation; and the microstructure analysis. The optimum of the grade and recovery of nickel was obtained at a temperature of 1050°C with the duration of process of 60 minutes and 5 wt% of reductant and 10 wt% of additive, which obtain 3.72 wt% and 95.67%. The metal grade and recovery was increase with the increasing of temperature reduction. Nevertheless, too long of the duration of process and too many reductant addition resulted in negative effect on selective reduction of lateritic nickel ore. Highest recovery could get more nickel in the process. And sulfur has the important rules when the selective reduction has been done on the increasing nickel content, the forming of FeS, and decreasing the grain size of ferronickel according to the microstructure in the SEM images around ~30 μm.
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Bibliography

Cao et al. 2010 – Cao, Z.C., Sun, T.C., Yang, H.F., Wang, J.J. and Wu, X.D. 2010. Recovery of iron and nickel from nickel laterite ore by direct reduction roasting and magnetic separation. Chinese Journal of Engineering 32(6), pp. 708–712, DOI: 10.13374/j.issn1001-053x.2010.06.004.
Dalvi et al. 2004 – Dalvi, A.D., Bacon, W.G. and Osborne R.C. 2004. The Past and The Future of Nickel Laterites. PDAC 2004 International Conference Trade Show and Investors Exchange, Toronto, Canada.
Elliot et al. 2015 – Elliot, R., Rodrigues, F., Pickles, C.A. and Peace, J. 2015. A two-stage process for upgrading thermal nickeliferous limonitic laterite ores. Canadian Metallurgical Quarterly 54(4), pp. 235–252, DOI: 10.1179/1879139515Y.0000000009.
Elliot et al. 2017 – Elliot, R., Pickles, C.A. and Peace, J. 2017. Ferronickel particle formation during the carbothermic reduction of a limonitic laterite ore. Minerals Engineering 100, pp. 166–176, DOI: 10.1016/j.mineng.2016.10.020.
Foster et al. 2016 – Foster, J., Pickles, C.A. and Elliot, R. 2016. Microwave carbhotematic reduction roasting of low-grade ore nickeliferous silicate laterite. Minerals Engineering 88, pp. 18–27, DOI: 10.1016/j.mineng.2015.09.005.
Jiang et al. 2013 – Jiang, M., Sun, T., Liu, Z., Kou, J., Liu, N. and Zhang, S. 2013. Mechanism of sodium sulfate in promoting the selective reduction of nickel laterite ore during reduction roasting process. International Journal of Mineral Processing 123, pp. 32–38, DOI: 10.1016/j.minpro.2013.04.005.
Li et al. 2012 – Li, G., Shi, T., Rao, M., Jiang, T. and Zhang, Y. 2012. Beneficiation of nickeliferous laterite by reduction roasting in the presence of sodium sulfate. Minerals Engineering 32, pp. 19–26, DOI: 10.1016/J.MINENG.2012.03.012.
Prasetyo, A.B. and Puguh. 2011. Increased levels of nickel (Ni) and iron (Fe) from laterite ore saprolite type low levels for raw materials containing nickel pig iron (NCPII/NPI). Met. Mag. 26, pp. 123–130.
Prasetyo, A.B. and Firdiyono, F.E. 2014. Reduction process optimization laterite ore limonite as raw materials type NPI (Nickel Pig Iron). Majalah Metalurgi 29(1), pp. 9–16.
Valix and Cheung. 2002. Effect of sulfur on the mineral phases of laterite ores at a high-temperature reduction. Minerals Engineering 15, pp. 523–530.
Wang et al. 2017 – Wang, Chu, Z., Liu, M., Wang, H., Zhao, W. and Gao, L. 2017. Preparing ferronickel alloy from low-grade laterite nickel ore reduction based on metallized-magnetic separation. Metals 7(8), pp. 313, DOI: 10.3390/met7080313.
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Authors and Affiliations

Fathan Bahfie
1
ORCID: ORCID
Achmad Shofi
2
Ulin Herlina
1
Anton S. Handoko
1
Nanda A. Septiana
3
Syafriadi Syafriadi
3
Suharto Suharto
1
Sudibyo Sudibyo
1
Suhartono Suhartono
4
Fajar Nurjaman
1

  1. Research Unit for Mineral Technology, National Research and Innovation Agency of Indonesia, Jalan Ir. Sutami Km 15 South Lampung, Lampung, Indonesia
  2. Agency for Rembang Regional Planning and Development, Rembang Local Government, Indonesia
  3. Department of Physic-University of Lampung,Jl. Prof. Dr. Ir. Sumantri Brojonegoro No. 1, Gedong Meneng, Kec. Rajabasa, Kota Bandar Lampung, Indonesia
  4. Chemical Engineering Department, University of Jenderal Achmad Yani, Jalan Terusan Jend. Sudirman, Cibeber, Kec. Cimahi Sel., Kota Cimahi, Jawa Barat, Indonesia
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Abstract

Tea mosquito bugs (TMB; Helopeltis bradyi, Hemiptera, Miridae) are a main pest in tea and cacao plantations worldwide. Pheromone-mediated mating disruption (MD) is a promising strategy to manage TMB populations. Experiments were conducted to evaluate the simultaneous effect of TMB female delayed mating (1, 3 and 5 days delayed mating) and pairing duration (1 day, 5 days, and entire lifespan) on several reproductive parameters. Results showed that female delayed mating obviously affected egg number, egg viability, and offspring number, but male delayed mating did not show such effects. Shortened pairing durations had a significant effect on egg viability and offspring number but not on egg number. Increased delayed mating and pairing duration negatively affected adult longevity. In general, we noted that TMB reproductive performance is vulnerable to delayed mating and shortened pairing durations, thus providing essential guidance for the implementation of MD strategies of TMB in the field.
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Authors and Affiliations

Indriani Feberati Putri
1
Suputa Suputa
1
Alan Soffan
1
ORCID: ORCID

  1. Department of Plant Protection, Universitas Gadjah Mada, Yogyakarta, Indonesia
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Abstract

The Randomized Earned Value Method enable to control the time and cost of works during the implementation of a construction project. The method allows to assess the compliance of the current advancement in time and actually incurred costs with the adopted plan. It also allows to predict the date and amount of the project completion costs. Individual assessment indicators (BCWS, BCWP, ACWP) are calculated after the ongoing control of the progression of works. In the case of randomly changing of implementation conditions, the calculated in this way values of the indicators may be unacceptable because of overlarge differences in comparison to actual values. Therefore, it is proposed an EVM enhancement and additional risk conditions analysis. In this approach data from the quantity survey of works are randomized based on analysis of variations between actually measured and planned values of duration and cost of implemented works. It is estimated the randomized values of individual indicators after successive controls of the progress of works. After each project advancement control the duration and cost of the works that remain to be performed are estimated. Moreover, new verified overall time and total cost of the project implementation are also estimated. After the last inspection, randomized values of the final date and total cost of completion of the project are calculated, as well as randomized values of time extension and total cost overrun. Of course, for randomized values, standard deviations of individual quantities are calculated. Therefore, the risk of time and the risk of cost of the project implementation are presented in the risk charts. The proposed approach provides a better assessment of the progress of works under risk conditions. It is worth to add that the method does not require significant changes to the typical construction management process, however, it ensures realistic consideration of the influence of random factors on the course and results of individual works and the entire project.
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Authors and Affiliations

Tadeusz Kasprowicz
1
ORCID: ORCID
Anna Starczyk-Kołbyk
1
ORCID: ORCID

  1. Military University of Technology, Faculty of Civil Engineering and Geodesy, ul. gen. Sylwestra Kaliskiego 2, 00–908 Warsaw, Poland
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Abstract

The main goal of this paper is to analyze the matching function in the Polish labour market in 1994‒2008. Matching function is the relationship between outflows from unemployment to employment and the number of unemployed persons and vacancies as well as other variables which affect the efficiency of the matching process directly or indirectly. Such matching function in its augmented form is estimated here for Poland with the use of data from register of unemployed persons.

The results indicate that there is a statistically stronger impact of the unemployed than vacancies on new hires. Furthermore, the institutional conditions of the labour market, the structure of the unemployed and the participants of active labour market programs (ALMP) play a role in the matching process.

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Authors and Affiliations

Sylwia Roszkowska
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Abstract

Synthetic modelling of the flood regime is based on the overall knowledge of the hydrological regime in a catchment. The Flow-duration-Frequency (QdF) modelling is used to combine three parameters characterising flood with its mean or exceeded flow, its characteristic duration, and occurrence frequency. Which of these can be established locally at the extreme mean volume flow rates of a catchment reference hydrometric station? The determination of the reference QdF model in mean (volume) and exceeded flows requires two characteristics reflecting the flood regime in a catchment. The first is the characteristic flood duration and the second is the 10-year quantile of the annual maximum instantaneous flow. The comparison of the local situation to the reference QdF models enables to develop the final QdF model of the catchment and therefore the baseline QdF for exceeded and synthetic mono-frequency hydrographs. These are essential components in the study of flood risk mapping and the estimation of the instantaneous peak distribution from mean daily streamflow series.
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Authors and Affiliations

Sofiane Kourat
1
ORCID: ORCID
Bénina Touaïbia
1
ORCID: ORCID
Abdelhalim Yahiaoui
2
ORCID: ORCID

  1. National Higher School of Hydraulic, Blida, Algeria
  2. University of Bouira, Institute of Technology, Rue Drissi Yahia, Bouira 10000, Algeria
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Abstract

This study aims to identify the potential predictors (i.e., financial well-being, mindfulness, and marital duration) of relationship satisfaction among married couples in Malaysia. Respondents were 156 Malaysian married couples from different races – Malay, Chinese, Indian, and others. All respondents responded to three questionnaires which are In Charge Financial Distress/ Financial Well-Being Scale (Prawitz et al., 2006), Mindfulness Attention Awareness Scale (Brown & Ryan, 2003), and Couple Satisfaction Index (Funk & Rogge, 2007). A significant positive relationship was found between financial well-being and mindfulness with relationship satisfaction, meanwhile, no statistically significant relationship was found between marital duration and relationship satisfaction. Moreover, mindfulness is established to be the strongest predictor of relationship satisfaction among married couples in Malaysia. This result emphasized the role of mindfulness within the context of development and sustainability of marital relationships satisfaction in addition to general well-being.
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Bibliography


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Authors and Affiliations

Athirah Yasmin Mohd Shakir
1
ORCID: ORCID
Dzilal Abdul Aziz
1
Suwathi Carmergam
1

  1. Management & Science University, Malaysia
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Abstract

Rainfall is one of the main components of the hydrologic cycle; thus, the availability of accurate rainfall data is fundamental for designing and operating water resources systems and infrastructure. This study aims to develop an empirical model of rainfall intensity ( It,p) as a function of its probability ( p) and duration ( t). In 1999–2020, data on the hourly duration of rainfall were collected from automatic rainfall recorder (ARR) gauges. The empirical model has been developed using a statistical approach based on duration ( t) and probability ( p), and subsequently they have been validated with those obtained from ARR data. The resulting model demonstrates good performance compared with other empirical formulas (Sherman and Ishiguro) as indicated by the percent bias ( PBIAS) values (2.35–3.17), ratio of the RMSE (root mean square error) between simulated and observed values to the standard deviation of the observations ( RSR, 0.028–0.031), Nash–Sutcliffe efficiency ( NSE, 0.905–0.996), and index of agreement (d, 0.96–0.98) which classified in the rating of “very good” in model performance. The reliability of the estimated intensity based on the empirical model shows a tendency to decrease as duration ( t) increases, and a good accuracy mainly for the rainfall intensity for shorter periods (1-, 2-, and 3-hours), whereas low accuracy for long rainfall periods. The study found that the empirical model exhibits a reliable estimate for rainfall intensity with small recurrence intervals ( Tr) 2-, 5-, 10-, and a 20-year interval and for a shorter duration ( t). Validation results confirm that the rainfall intensity model shows good performance; thus, it could be used as a reliable instrument to estimate rainfall intensity in the study area.
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Authors and Affiliations

Donny Harisuseno
1
ORCID: ORCID
Linda Prasetyorini
1
ORCID: ORCID
Jadfan S. Fidari
1
ORCID: ORCID
Dian Chandrasasi
1
ORCID: ORCID

  1. University of Brawijaya, Faculty of Engineering, Water Resources Engineering Department, MT. Haryono Street No. 167, 65145, Malang, Indonesia
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Abstract

Precipitation is a component of the hydrological cycle, knowing its spatial distribution is vital for the management of hydrographic basins, the territory and the development of fundamental activities for society. That is why the present study shows the spatial variability of rainfall in Cartagena de Indias city with a network of rain gauges, made up of nine pieces of equipment, separated from each other by 0.9–27 km. After a year of recording (2019), using historical series of data, it was found that the maximum rainfall occurs in the trimester between September and November, with interpolated maps made by the Ordinary Kriging (OK) method it was found that the maximum rainfall is focused on the north, centre and west of the territory, instead, the maximum intensities are presented in the centre and west, the minimums for both variables are presented to the east and south. The 70 and 90% of the rain events have a duration of less than 30 min and 1 h, respectively. Three-parameter exponential function was fitted to the paired correlation distances, and presented correlations lower than 0.8, 0.5 and 0.2 from distances of 1, 3 and 7 km, respectively, in 30 min rain integration. It was also found that with a pluviometric network conformed by at least six pieces of equipment and separated by a 5 km distance from each other in the urban area, a correlation of 0.5 and compliance with the WMO recommendations would be obtained.
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Authors and Affiliations

Javier A. Mouthon-Bello
1
Edgar Quiñones-Bolaños
1
ORCID: ORCID
Jairo E. Ortiz-Corrales
1
ORCID: ORCID
Natalia Mouthon-Barraza
1
Maria D.J. Hernández-Fuentes
1
Andrea C. Caraballo-Meza
1

  1. Universidad de Cartagena, Faculty of Engineering, Department of Civil Engineering, Consulate Ave 30, No. 48-152, 130014, Cartagena de Indias, Colombia
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Abstract

At present, Pakistan has been facing acute shortage of irrigation water and farmers have been using conventional irrigation methods for orchards, such as flood and basin irrigation, thus wasting huge amount of fresh water. Therefore, it is necessary to find efficient irrigation methods to cope with this major burning issue. The micro drip irrigation method is considered efficient but in the case of mango orchards there is a problem of irrigation frequency, number of emitters, and duration of flow from emitters to meet water demand. Considering the above, an experiment was conducted in the experimental field of the Sindh Agriculture University, Tandojam, by installing the drip system with two circular peripheries of lateral lines in clay loam soil covering the entire canopy of a mature mango tree. The radius of the first and second periphery around the tree trunk was 100 cm and 150 cm, respectively. Four emitters with 4 dm3∙h –1 discharge of individual dipper were fixed in each periphery. Emitters were tested for six different irrigation times, i.e. 1, 2, 3, 4, 5 and 6 h, to observe the moisture distribution pattern. Hydraulic characteristics, such as density, field capacity, porosity, infiltration rate, available water and permanent wilting point (PWP), were determined using standard methods (1.4 g∙cm –3, 33%, 49%, 8 mm∙h –1, 12.41% and 20% respectively). The texture class of the soil profile was determined as clay loam at the soil depth 0–120 cm. Fifty soil samples were collected at 0–10, 10– 30, 30–60, 60–90, and 90–120 cm depths and at 0–20, 20–40, 40–60, 60–80 and 80–100 cm distances on two opposite sides of emitters. The emitters provided sufficient moisture up to field capacity in clay loam soil with flow duration of 4 h. The maximum moisture distribution efficiency was 77.89% with flow duration of 4 h at vertical depth of 0–120 cm and 0–100 cm distance horizontally among four emitters as compared to 1, 2, 3 h flow duration which under irrigated the canopy area and 5, 6 h flow duration which excessively irrigated the canopy area of the mango tree. The water demand of the mango tree was met by 4 h flow duration which provided adequate moisture to the entire canopy up to 120 cm depth in the root zone and water saving was calculated as 15.91% under the installed drip irrigation system as compared with the conventional (basin) irrigation method.
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Authors and Affiliations

Shoukat Ali Soomro
1
ORCID: ORCID
Muhammad Saffar Mirjat
1
Munir Ahmed Mangrio
1
Mashooque Ali Talpur
1

  1. Sindh Agriculture University, Tandojam, Faculty of Agricultural Engineering, 70060, Hyderabad, Pakistan
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Abstract

Sub-bottom profiler (SBP) is an acoustic instrument commonly used to survey underwater shallow geological structure and embedded objects whose most important performance parameter is the actual vertical resolution. This paper presented a methodology to measure and evaluate the actual vertical resolution of SBP based on an experiment in an anechoic tank, which was divided into three components: building of artificial geological model, measurement of acoustic parameters, and determination of actual vertical resolution of the acoustic profiles. First, the wedge-shaped geological model, whose thickness could be accurately controlled, was designed and built in an anechoic tank to try to directly measure the vertical resolution of SBP. Then, the acoustic pulse width of SBP was measured to calculate the theoretical general vertical resolution and extreme vertical resolution. Finally, based on the acoustic profiles obtained in the experiment, the method which was used to evaluate the actual vertical resolution by measuring the duration of reflection event was put forward. Due to comparing measurement data of different parameter settings of the SBP, the study has revealed that the SBP had the lowest resolution in the 4 kHz–500 µs setting, which was 226.5 µs, or 36.2 cm, and the highest resolution in the 15 kHz–67 µs setting, which was 72.7 µs, or 11.6 cm. The vertical resolution decreased with the increase of the pulse width. The results also showed that the actual resolution was close to the theoretical general resolution and far from the extreme resolution.

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Authors and Affiliations

Fangqi Wang
Lifeng Dong
Jisheng Ding
Xinghua Zhou
Changfei Tao
Xubo Lin
Guanhui Liang
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Abstract

To examine the correlation of driver visual behaviors and subjective levels of fatigue, a total of 36 commercial drivers were invited to participate in 2-h, 3-h, and 4-h naturalistic driving tests during which their eye fixation, saccade, blinking variables, and self-awareness of their fatigue levels were recorded. Then, one-way ANOVA was applied to analyze the variations of each variable among different age groups over varying time periods. The statistical analysis revealed that driving duration had a significant effect on the variation of visual behaviors and feelings of fatigue. After 2h of driving, only the average closure duration value and subjective level of fatigue had an increase of one-fifth or more. After 4h of driving, however, all these variables had a significant change except for the number of saccades and pupil diameter measurements. Particularly, driver saccadic eye movement was more sensitive to driving fatigue, and the elderly were more likely to be affected by the duration of the drive. Finally, a predictor of driver fatigue was determined to detect the real-time level of fatigue and alert at the critical moment.

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Authors and Affiliations

Yonggang Wang
ORCID: ORCID
Jingfeng Ma
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Abstract

In recent years, autoregressive conditional duration models (ACD models) introduced by Engle and Russell in 1998 have become very popular in modelling of the durations between selected events of the transaction process (trade durations or price durations) and modelling of financial market microstructure effects. The aim of the paper is to develop Bayesian inference for the ACD models. Different specifications of ACD models will be considered and compared with particular emphasis on the linear ACD model, Box-Cox ACD model, augmented Box-Cox ACD model and augmented (Hentschel) ACD model. The analysis will consider models with the Burr distribution and the generalized Gamma distribution for the innovation term. Bayesian inference will be presented and practically used in estimation of and prediction within ACD models describing trade durations. The MCMC methods including Metropolis-Hastings algorithm are suitably adopted to obtain samples from the posterior densities of interest. The empirical part of the work includes modelling of trade durations of selected equities from the Polish stock market.

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Authors and Affiliations

Roman Huptas
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Abstract

In empirical research on financial market microstructure and in testing some predictions from the market microstructure literature, the behavior of some characteristics of trading process can be very important and useful. Among all characteristics associated with tick-by-tick data, the trading time and the price seem the most important. The very first joint model for prices and durations, the so-called UHF-GARCH, has been introduced by Engle (2000). The main aim of this paper is to propose a simple, novel extension of Engle’s specification based on trade-to-trade data and to develop and apply the Bayesian approach to estimation of this model. The intraday dynamics of the return volatility is modelled by an EGARCH-type specification adapted to irregularly time-spaced data. In the analysis of price durations, the Box-Cox ACD model with the generalized gamma distribution for the error term is considered. To the best of our knowledge, the UHF-GARCH model with such a combination of the EGARCH and the Box-Cox ACD structures has not been studied in the literature so far. To estimate the model, the Bayesian approach is adopted. Finally, the methodology developed in the paper is employed to analyze transaction data from the Polish Stock Market.

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Authors and Affiliations

Roman Huptas
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Abstract

Redundancy based methods are proactive scheduling methods for solving the Project

Scheduling Problem (PSP) with non-deterministic activities duration. The fundamental

strategy of these methods is to estimate the activities duration by adding extra time to the

original duration. The extra time allows to consider the risks that may affect the activities

durations and to reduce the number of adjustments to the baseline generated for the project.

In this article, four methods based on redundancies were proposed and compared from two

robustness indicators. These indicators were calculated after running a simulation process.

On the other hand, linear programming was applied as the solution technique to generate

the baselines of 480 projects analyzed. Finally, the results obtained allowed to identify the

most adequate method to solve the PSP with probabilistic activity duration and generate

robust baselines.

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Authors and Affiliations

Nestor Raul Ortiz-Pimiento
Francisco Javier Diaz-Serna
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Abstract

This article analyses the conditions affecting the incoming global solar radiation in Hornsund (Spitsbergen) in spring of 2015. Incoming solar radiation turned out to be average for the season under analysis, as compared with longer-term data. The clearness index (KT) was 0.46, and was mainly determined by the extent of cloudiness. As a result of differences in the length of day, sunshine duration in May was greater than in April. Incoming solar radiation to the earth's surface is also affected by the atmospheric optical properties. The average value of aerosol optical depth (AOD) at 500 nm in Hornsund in spring of 2015 was 0.087. In the analysed period, increased values of AOD at 500 nm (up to 0.143) were observed, although these are not record values. Over April and May, the greatest part of optical depth was comprised of anthropogenic aerosols (41%), followed by marine aerosols (26%), desert dust (21%) and biomass-burning aerosols (12%). This indicates the significant role of the anthropogenic factor in the climatic conditions of Spitsbergen.
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Authors and Affiliations

Joanna Uscka-Kowalkowska
Rajmund Przybylak
Krzysztof M. Markowicz
Andrzej Araźny
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Abstract

Gauging stations of meteorological networks generally record rainfall on a daily basis. However, sub-daily rainfall observations are required for modelling flood control structures, or urban drainage systems. In this respect, determination of temporal distribution of daily rainfall, and estimation of standard duration of rainfall are significant in hydrological studies. Although sub-daily rainfall gauges are present at meteorological networks, especially in the developing countries, their number is very low compared to the gauges that record daily rainfall.
This study aims at developing a method for estimating temporal distribution of maximum daily rainfall, and hence for generating maximum rainfall envelope curves. For this purpose, the standard duration of rainfall was examined. Among various regression methods, it was determined that the temporal distribution of 24-hour rainfall successfully fits the logarithmic model. The logarithmic model’s regression coefficients (named a and b) were then linked to the geographic and meteorological characteristics of the gauging stations. The developed model was applied to 47 stations located at two distinct geographical regions: the Marmara Sea Region and Eastern Black Sea Region, Turkey. Various statistical criteria were used to test the method's accuracy, and the proposed model provided successful results. For instance, the RMSE values of the regression coefficients a and b in Marmara Regions are 0.004 and 0.027. On the other hand, RMSE values are 0.007 and 0.02 for Eastern Black Sea Region.
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Authors and Affiliations

Cahit Yerdelen
1
ORCID: ORCID
Ömer Levend Asikoglu
1
ORCID: ORCID
Mohamed Abdelkader
1
ORCID: ORCID
Ebru Eris
1
ORCID: ORCID

  1. Ege University, Faculty of Engineering, 35100, Bornova – İZMİR, Turkey
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Abstract

In Western music culture instruments have been developed according to unique instrument acoustical features based on types of excitation, resonance, and radiation. These include the woodwind, brass, bowed and plucked string, and percussion families of instruments. On the other hand, instrument performance depends on musical training, and music listening depends on perception of instrument output. Since musical signals are easier to understand in the frequency domain than the time domain, much effort has been made to perform spectral analysis and extract salient parameters, such as spectral centroids, in order to create simplified synthesis models for musical instrument sound synthesis. Moreover, perceptual tests have been made to determine the relative importance of various parameters, such as spectral centroid variation, spectral incoherence, and spectral irregularity. It turns out that the importance of particular parameters depends on both their strengths within musical sounds as well as the robustness of their effect on perception. Methods that the author and his colleagues have used to explore timbre perception are: 1) discrimination of parameter reduction or elimination; 2) dissimilarity judgments together with multidimensional scaling; 3) informal listening to sound morphing examples. This paper discusses ramifications of this work for sound synthesis and timbre transposition.

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Authors and Affiliations

James Beauchamp

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