46 research outputs found
Workload analysis in logging technology employing a processor aggregated with a farm tractor
Panel analysis of home prices in the primary and secondary market in 17 largest cities in Poland
We analyse the determinants of house prices in the primary and secondary market of 17 largest cities in Poland during the 2002-2013 period. We find that prices are driven by economic fundamentals, such as income growth or rise in employment. Prices in the secondary market react to increases in the loan availability, that was driven by low interest rates resulting from FX denominated housing loans that were granted since 2006. This finding does not hold for the primary market, which is to a large extent financed with cash. We confirm empirically that the house appreciation in the past period has a strong effect on the current price, which confirms herding behaviour in the housing market. Another finding is that the secondary market has a stronger effect on the primary market than the other way around. This means that housing demand is satisfied in the first place from the secondary market, and if prices rise, potential buyers go to the primary market. Finally, we find that price increases in Warsaw spill over to the local markets of 16 regional cities. This finding is consistent with the contagion theory in the real estate market, according to which price increases in the centre lead to price increases in the periphery
On the dynamics of the primary housing market and the forecasting of house prices
This article discusses and explains the dynamics of the primary housing market, focus-ing on housing supply, demand, price and construction costs dynamics. We focus our attention on the primary housing market, because it can create an excessive supply, which can cause distress to the economy.
Due to multiplier effects, even small changes in fundamental factors, such as a minor changes in the interest rate, result in demand shocks. Positive demand shifts cannot be easily satisfied, as supply is rigid in the short run. This usually makes house prices grow and developers increase their production, which will be delivered to the market with a lag. Housing developers have the marketing tools to heat up the market for a prolonged period of time. Rising prices can lead to further demand increases, because housing is a consumer and an investment good. When demand moves back to its long run level, the economy is left with excessive supply, falling prices and bad mortgages.
We create a simple four-equation model, which is able to replicate the dynamics of the Warsaw primary housing market. Our model replicates historical data in an appropriate way and we apply it to forecast house prices in the next two years on quarterly basis
On the dynamics of the primary housing market and the forecasting of house prices
This article discusses and explains the dynamics of the primary housing market, focus-ing on housing supply, demand, price and construction costs dynamics. We focus our attention on the primary housing market, because it can create an excessive supply, which can cause distress to the economy.
Due to multiplier effects, even small changes in fundamental factors, such as a minor changes in the interest rate, result in demand shocks. Positive demand shifts cannot be easily satisfied, as supply is rigid in the short run. This usually makes house prices grow and developers increase their production, which will be delivered to the market with a lag. Housing developers have the marketing tools to heat up the market for a prolonged period of time. Rising prices can lead to further demand increases, because housing is a consumer and an investment good. When demand moves back to its long run level, the economy is left with excessive supply, falling prices and bad mortgages.
We create a simple four-equation model, which is able to replicate the dynamics of the Warsaw primary housing market. Our model replicates historical data in an appropriate way and we apply it to forecast house prices in the next two years on quarterly basis
Carotid endarterectomy in patients with contralateral internal carotid artery occlusion
Wstęp. Zakrzepica tętnicy szyjnej wewnętrznej u około 1/3 chorych
prowadzi do udaru mózgu. Celem pracy jest ocena wyników endarterektomii tętnicy
szyjnej wewnętrznej w zależności od drożności przeciwstronnej tętnicy szyjnej wewnętrznej.
Materiał i metody. W latach 1990–1998 wykonano 422 zabiegów endarterektomii
u 390 chorych, których podzielono na 2 grupy. W grupie I było 65 chorych (16,7%)
z niedrożną przeciwstronną tętnicą szyjną wewnętrzną, natomiast grupę II stanowiło
325 chorych (83,3%) z zachowaną drożnością tętnicy po stronie przeciwnej. Operowano
przede wszystkim chorych (94,8%) z dużym (> 70%) zwężeniem tętnicy szyjnej
wewnętrznej. Występowanie czynników ryzyka nie różniło się w obu grupach. W grupie
I znamiennie częściej (p = 0,01) stwierdzano pełnoobjawowy udar ze strony operowanej
tętnicy. Wykonywano standardową endarterektomię z pierwotnym szwem tętnicy.
Wyniki. Przedoperacyjna tomografia komputerowa znamiennie częściej (p <
0,001) wykazywała ognisko niedokrwienia mózgu po stronie operowanej w grupie I.
Czasowy przepływ wewnętrzny znamiennie częściej (p < 0,001) stosowano u chorych
z przeciwstronną niedrożnością tętnicy szyjnej wewnętrznej. Udar mózgu po stronie
operowanej stwierdzano u 3% chorych w grupie I i u 3,1% chorych w grupie II. Przeciwstronny
udar wystąpił u 1,5% osób w grupie I oraz u 0,56% osób w grupie II. Śmiertelność
wynosiła: 1,5% w grupie I i 1,3% w grupie II.
Wnioski. Ryzyko powikłań oraz śmiertelność okołooperacyjna po endarterektomii
szyjnej w badanej grupie nie są większe u chorych z przeciwstronną niedrożnością
tętnicy szyjnej wewnętrznej. W grupie I znamiennie częściej zachodziła potrzeba
zastosowania czasowego przepływu wewnętrznego.Introduction. Carotid artery occlusion is the cause of death
or disabling cerebral symptoms in 1/3 of patients. The aim of the study was to
analyse the perioperative results of carotid endarterectomy (CEA) depending on the
patency of the contralateral internal carotid artery (ICA).
Material and methods. Four hundred and twenty-two CEA were performed in
390 patients between 1990–1998. Sixty-five (16.7%) patients had contralateral
ICA occlusion (group I). The rest, 325 patients (83.3%), had patent contralateral
ICA - group II. We operated on mainly severe (> 70%) ICA stenoses (94.8%).
The preoperative risk factors were similar in both groups. Preoperative severe
stroke on the operated ICA side was significantly more often observed in group
I (p = 0.01). Standard CEA with direct arterial suture was performed in all cases.
Results. Preoperative computed tomography (CT) scan revealed more often
ischaemic focus on the operated side in group I (p < 0.001). Intraoperative
shunt was significantly more often used in patients with contralateral ICA occlusion
(p < 0.001). The perioperative stroke from the operated side was observed in
3% patients from group I and in 3.1% from group II. Contralateral stroke occurred
in 1.5% from group I, and 0.56% from group II. Mortality rate was respectively
1.5% for group I, and 1.3% for group II (p = NS).
Conclusions. Risk of preoperative stroke and mortality rate were not higher
for patients with contralateral ICA occlusion. Intraoperative shunt was significantly
more often used in patients with contralateral ICA occlusion
The concentration of carbon monoxide in the breathing areas of workers during logging operations at the motor-manual level
Efficiency and Ability of Employees to Work in Relation to Timber Quality and Structural Ageing
Small and medium-sized enterprises play a crucial role in job creation in the wood industry. The process of employee ageing and avoidance of heavy physical effort affect the labour market contribution. The need to increase work efficiency is certainly reflected in the pressures on employees. Workplace health investigations with the Work Ability Index (WAI) is a one of several tools that take into account job requirements, the employee health status and their resources. In the conducted study, an attempt was made to assess the workability of logging workers in the private sector of small and medium-sized enterprises. Excellent work readiness was found only among harvester and forwarder operators aged 20-30. Different dynamics of WAI decline as a function of age were also observed. In general, for the study group, the WAI fluctuated at a moderate level depending on the technical equipment, age of the employees, BMI, log dimensions and quality (pulp, industry or large saw log wood) or machine productivity. The worst situation was observed during silvicultural treatments of deciduous (beech) stands using the cut-to-length (short saw log wood harvesting) method. Ageing, being overweight, deteriorating health and the mainly physical nature of work are risk factors for low (mediocre) work capacity. It can partially be modelled by increasing employee engagement through an appropriate incentive system. We often observed differences between the work demands determined by the employer's expectations and the social, physical, and health limitations of employees, which led them to seek easier jobs
The concentration of carbon monoxide in the breathing areas of workers during logging operations at the motor-manual level
Objectives: This article compares 2 variants of logging technologies at the motor-manual level: variant A – cutting and delimbing by means of a petrol chainsaw, skidding with the use of a cable winch mounted on a tractor (67–74 kW); variant B – cutting by means of a petrol chainsaw, skidding, debranching and cutting to length by means of a processor aggregated with a farm tractor (61 kW). Material and Methods: Direct dosimetry and non-parametric (moving block bootstrap) methods were used in order to specify the characteristics of the collected sets. Results: Bootstrap average values show that the average CO concentration at a skidding tractor operator’s station during early thinning was 2.54 mg×m–3. At processor operator’s station it amounted to 10.35 mg×m–3. Such results allow to conclude that a higher CO concentration at the above-mentioned 2 work stations was observed during early thinning. In the case of a petrol chainsaw operator, it was observed that the permissible exposure limit (23 mg×m–3) was exceeded and the short-term permissible exposure limit (117 mg×m–3) was not. The average concentration value for a chainsaw operator working individually during late thinning interventions was substantially lower (15.01 mg×m–3), which results from the lack of technological pressure that can be observed while cooperating with a processor operator. Conclusions: The risk increases along with conditions that generate the concentration of exhaust produced by 2-stroke petrol chainsaw engines