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The efficiency of the foreign exchange market is crucial because exchange rates play a vital role in balancing a nation's internal and external economies. Iran's foreign exchange market has undergone significant developments and fluctuations in recent years, impacting its efficiency. This is evident in the monthly time series data for the unofficial exchange rates of the dollar, euro, and yuan from 2001 to 2021. An interesting trend has emerged since 2017: the Chinese yuan appears to be gradually replacing the dollar and euro as the primary trading currency in Iran's international market. Statistical tests, including the Augmented Dickey-Fuller (ADF), Phillips-Peron (PP), and KPSS tests, indicate weak-form efficiency in the markets for all three currencies (dollar, euro, and yuan). This suggests that these markets remain vulnerable to speculative attacks. Furthermore, Johansen's cointegration and Granger's causality tests reveal an absence of semi-strong efficiency in all three markets. This implies that past price information alone is insufficient to predict future exchange rates. The research findings suggest that choosing the yuan as an alternative currency has had a somewhat positive impact on improving the efficiency of the Iranian currency market.

In the past, mill races were part of the urban structure of many towns in Slovakia. As regulated and artificially created waterways, they served to drive mills, rollers, or hammers. With the use of new sources of energy, they lost their functions, and most of them were dried, filled, or buried underground. In our research, we examine the former mill race corridor in Podolínec (Prešov region, Slovakia) and its potential to contribute to urban regeneration strategies. The research steps included the following, namely 1. Identification of the route of the mill race corridor according to historical sources, 2. survey of its current state and its spatial preservation in the urban structure, 3. evaluation of the possibilities of its new uses, which could increase the quality and attractiveness of urban public spaces. The research results show that the fragments of the corridor of the extinct mill race are still identifiable in the urban fabric, and in the cadaster, they are in public ownership and suitable for new uses. The fragments of the corridor of the extinct mill race in Podolínec represent a potential for strengthening the blue and green infrastructure, pedestrian and cycling greenways, and a potential for the presentation of cultural heritage values, which could contribute to the improvement of the qualities of the urban environment.

Traditional Iranian architecture principles have deep roots in this region's culture, thoughts, and climatic conditions. Privacy, as one of these principles, which has ever regulated all aspects of life, has been beautifully embodied in the vernacular residential architecture of Iran. It proved to have profound effects which resulted in a specific spatial organization of the house and the placement of various functions, either private or semi-private. Many research studies have claimed that privacy was an attribute of Islamic rules in Iranian architecture. Based on historical and phenomenological analyses of vernacular Iranian architecture this paper strives to confront the privacy principle also according to Iranian (or former Persian) culture, climate, and security conditions. Changed geopolitical and cultural conditions in the 20th century raised new forms of architectural residential morphology almost completely negating the principle of privacy. The question is whether the vernacular principle of privacy should be embodied in the new design of Iranian residential houses or be preserved merely as an expression of former culture increasing the quality of the image of the city and its attractiveness. The research completed by qualitative morphological and analytical methods clarifies the mentioned principles and identifies the definition of privacy, the factors affecting it, the roots of its formation, its influence on the physical-spatial organization of traditional residential architecture in Iran, and its continuation in modern residential architecture in Iran.

Urban overheating, intensified by climate change, poses a critical challenge in Central European cities, witnessing a rise in tropical days. Conventional mechanical cooling systems in buildings significantly contribute to carbon dioxide emissions, exacerbating global warming. In response, windcatchers—traditional Iranian natural cooling systems—emerge as a promising sustainable solution for contemporary architecture, even in non-arid climates. This research aims to evaluate windcatchers’ efficacy in improving building thermal comfort in Central European climates, focusing on Vienna’s urban environment. This study identifies optimal windcatcher designs by analyzing key variables: height variation, inlet dimensions, urban exposure, Building Management System (BMS) temperature thresholds, and integration with an earth tube system using Design Builder simulation software version 6. The findings reveal that a windcatcher standing at 2.5 m tall, with inlet dimensions of 0.9 m by 1.4 m, in an open, less densely populated urban setting, and with open valves when indoor temperatures surpass 22 °C, demonstrates the most effective reduction in cooling load. Moreover, both one-sided and two-sided windcatchers outperform conventional ventilation through openings. Additionally, combining a one-sided windcatcher with an earth tube system ensures efficient cooling even when exterior temperatures exceed 25 degrees Celsius. When augmented by a heat pump, this integrated system can provide heated ventilation.

Abstract Online non‐invasive methods to assess circuit breaker condition have been under consideration in recent years. The combination of the arcing time and the short‐circuit current recorded by protective relays can be utilized to assess the degrading impact of current interruption on arcing contacts. In many previous investigations, an integral over arcing time of different functions of current and voltage has been proposed to predict the erosion rate of arcing contacts. Although the arcing time is a crucial parameter for these indices, no easily adaptable method to online condition assessment is available. This paper proposes a method for online determination of arcing time based on the measurement of the switching time of the auxiliary contacts. Several experiments have been performed under no‐load conditions as well as during short‐circuit current interruption, on two circuit breakers with different trip coil excitations (AC and DC). The results show that the delay time between the contact separation instant of the arcing contacts and the switching time of the auxiliary contacts has a very low jitter. This enables precise determination of the arcing time by measurement of the switching time of the auxiliary contacts, which is accessible during the online operation of circuit breakers.

In the past, mill races were part of the urban structure of many towns in Slovakia. As regulated and artificially created waterways, they served to drive mills, rollers, or hammers. With the use of new sources of energy, they lost their functions, and most of them were dried, filled, or buried underground. In our research, we examine the former mill race corridor in Podolínec (Prešov region, Slovakia) and its potential to contribute to urban regeneration strategies. The research steps included the following, namely 1. Identification of the route of the mill race corridor according to historical sources, 2. survey of its current state and its spatial preservation in the urban structure, 3. evaluation of the possibilities of its new uses, which could increase the quality and attractiveness of urban public spaces. The research results show that the fragments of the corridor of the extinct mill race are still identifiable in the urban fabric, and in the cadaster, they are in public ownership and suitable for new uses. The fragments of the corridor of the extinct mill race in Podolínec represent a potential for strengthening the blue and green infrastructure, pedestrian and cycling greenways, and a potential for the presentation of cultural heritage values, which could contribute to the improvement of the qualities of the urban environment. [ABSTRACT FROM AUTHOR]

Silicone rubber (SR) is high-voltage insulator, but suffers from poor mechanical properties. Nanoparticle addition is a promising way to combat this problem. Herein, SiO2, Al2O3, MgO, SiC and thermally modified SiC nanoparticles were used to improve electrical resistivity, thermal stability and mechanical properties of SR. Surprisingly, electrical resistivity of SR was enhanced by one-order-of-magnitude by incorporation of small amount of nanoparticles, which induced nano-scale traps to capture charge carriers and restrict SR molecules conformation. Tensile strength and modulus of SR increased by SiO2, Al2O3, MgO and SiC incorporation, while decreased elongation at break, as a consequence of agglomeration as detected by microscopic observations. Nano fillers restricted the motion of polymer chains, so storage modules and hardness were increased. Addition of 2 phr SiC resulted in less polarization current comparably. Correspondingly, dielectric breakdown strength of the assigned sample was increased. SiC thermally modified interface is more conductive than the other parts of the matrix reduced charge accumulation and provide more conductive ways for increased charge carriers mobility, dissipate more charges and then increased dielectric breakdown strength. Dynamic-mechanical-thermal analyses demonstrated that storage modulus of SR nanocomposites was comparatively higher than neat SR, owing to rigidity contributed from SiO2 and SiC nanoparticles. Evidently, glass transition temperature shifted to a higher temperature (−109°C) compared to the neat SR (−127°C). Thermogravimetric analysis witnessed superiority of thermal stability of nanocomposites compared to SR, featured by 35°C rise in degradation temperature. The presence of nanoparticles in the polymer matrix acts as a barrier and prevents the release of gaseous products from burning and the entry of oxygen into the system lead to increase thermal stability. [ABSTRACT FROM AUTHOR]

In this paper, a lumped RC circuit model, which is based on the Transmission Line Modeling (TLM) method, is used to describe the space charge production and displacement mechanisms in three different solid dielectric materials (LDPE, PTFE and FR4). Each dielectric material is considered as a transmission line with the capacitive and resistance elements. The obtained circuit equations are solved along with the continuity equations for the various charged species in the bulk of solid dielectric material. The electric potential and field, density of different charged species and their recombination rates, resistive and capacitive properties of the solid dielectric material are calculated. In addition, the effects of the variations in the applied voltage, dielectric permittivity and temperature on these physical parameters are examined. Besides, compared with LDPE and PTFE, the net charge density increment rate in FR4 is much higher. Moreover, the influences of temperature on the net charge density in LDPE are not significant. Furthermore, at the higher applied voltages, the current density is increased. Interestingly, the effects of temperature variations on the recombination rates, net charge and current density in LDPE are much lower. Hence, the suitability of LDPE as solid dielectric material is proved.

Some economists believe that economic crises and problems, such as economic volatility, high unemployment and inflation and the social losses, stem from the government's economic intervention and the implementation of its imperative policies. In this regard, the lack of implementation of the government’s imperative policies by central bank and its independence is still a controversial issue. In the present paper, using Stackelberg model and game theory approach, the efficiency of bond issuance is evaluated as a result of central bank independence and its effect on social loss. For this purpose, a 3-player game including government, central bank and speculators having different objective functions, is designed for Iran. Modeling and numerical analyzing are performed using softwares GAMS and MAPLE during 2005 to 2009. According to minimization of social loss, the results indicate if the government does not play a dominant leadership role, and conversely, if the central bank exerts its leadership in making monetary policy via open market operations (central bank independence), the social loss can be reached to its minimum level.