In recent decades, the inflation phenomenon has been one of the most important issues for Iranian economy. Regardless of its effects on economy, identifying the determinants of inflation has always been a challenge in all economies. Therefore, in order to compare the endogenous money theory with the quantity theory of money, this study analyzes the relationship between inflation and its determinants. To this end, the spectral analysis approach at high and low frequencies is applied during the period 1991: Q1 to 2018: Q1. The results show that there is the causality relationship from the growth of liquidity towards inflation as well as from inflation to liquidity in the short- term and long-term. In addition, there is the causality relationship from the monetary base growth to inflation in the long-term, while this causal relationship runs from monetary base growth towards inflation in the short-term. Moreover, the causality relationship from money multiplier growth to inflation is confirmed in the long-term. Consequently, the causes of inflation are different in the short- and long-term.

Foundations are sometimes located either on a sloped surface or near the crown of a slope. Obvious examples can be seen in the footings of bridges abutments, foundations near excavations, retaining walls, and electric transmission towers built on mountain slopes. When the footing is placed near the edge of sloping ground, the bearing capacity may be significantly reduced, depending on the location of the footing concerning the slope. Therefore, the bearing capacity and stability of a slope is one of the most important research issues in geotechnical engineering. The adjacent soil's bearing capacity and the slope's stability can be increased by installing continuous confining structures like skirts. Skirted foundations are a type of shallow foundation with internal or lateral skirts made of steel or reinforced concrete. Using a skirt due to confinement of the soil beneath the foundation and transmitting the shear Failure at the level of the skirt tip. In this research, a series of laboratory tests were conducted on strip footing models adjacent to sand slope whit one side vertical skirt to evaluate the load-settlement response subjected to vertical compression loading. The effects of skirt depth (Hs) and setback distance (b) of the model on the bearing capacity and settlement of skirted foundations were studied. The results of the model tests have shown that using skirts improves the bearing capacity and settlement values of skirted foundations compared with shallow foundations without a skirt. The ultimate bearing capacity of skirted foundations increases up to about 104 to 232% with increasing the ratio of skirt depth to foundation width. To investigate the effect of setback distance on the skirted foundation behavior, three different distances of footing from crest to the width of the footing of 0, 1, and 2 were used. The results showed that the increase in the ratio of the distance of footing from the crest to the width of footing caused to increase in the ultimate bearing capacity of only footing. The results showed when the skirted footing is placed directly at the crest (b=0), increasing the depth of skirts leads to a significant increase in the bearing capacity. By increasing the edge distance from the slope crest to the footing, the effect of utilized skirts decreases. The Settlement Reduction Factor (SRF) decreased from 4 to 72% with the increase in the depth of the skirt and with a decrease in setback distance. Furthermore, the effect of a single-side skirt strip foundation resting on the top of the sand slope was investigated on the values of foundation tilting and failure mechanism. Evaluating results showed that strip footing near the slope has a clockwise tilt angle and after using one single skirt the tilt angle got changed. It was observed that in setback distance b/B=0 under s/B=15% with an increase in skirt depth (Hs=1b, 3B), the reduction values of footing tilt were from 46 to 24%, respectively. In the end, utilized skirts affect the failure mechanism and dependent on skirt length and setback distance change the failure pattern of the soil, face failure to toe, or base failure.

 It is common to apply physical modeling for a more precise investigation of phenomena in geotechnical engineering. The reconstitution of specimens is an appropriate way to study soil behavioral parameters in laboratories due to the restrictions of acceptable undisturbed sample preparation. Reconstitution of the sand sample is one of the most well-known challenges of physical modeling. One of the most significant aspects of physical modeling geotechnical engineering is the repeatability of bed preparation. The reconstitution of sample and bed preparation in physical modeling are divided into two general approaches, depending on the type of porosity control employed. Methods where the porosity is adjusted after deposition, is only appropriate for dense beds with diverse layers. This category includes the methods of tamping and vibration. Another methods where the porosity is controlled during deposition, which aim at obtaining any porosity within the maximum-minimum porosity limits of the material that is pluviation technique. Because of the favorable conditions and prompt modeling it enables, the preparation of layers by the pluviation technique is one of the most reliable bed preparation methods. The pluviation technique can be divided into three categories, air pluviation, vacuum pluviation, and water pluviation. In addition, each category is divided into three minor subgroups that monitor sand-rain outflow intensity as follows, controlling the deposition intensity of sand output from single or multiple nozzles of various shapes, controlling the deposition intensity of the sand output from single or multiple sieves, controlling the deposition intensity of the sand output from longitudinal aperture (curtain pluviation). The effective parameters on pluviation system are deposition intensity and fall height. Deposition intensity, itself, is affected by aperture width, traveling pluviator speed, and the number of opening. The sand reconstitution technique must properly provide real sample conditions in a wide range of soil density (loose to dense), the uniform void ratio in the entire reconstructed specimen, fully saturated conditions for undrained status, the samples should be well mixed without particle size segregation, regardless of particle size gradation and simulation of the studied depositional fabric characteristic.
In this research, a novel approach focusing on a traveling sand pluviator with two apertures was developed for the reconstitution of large-scale samples. Experiments on Iran’s Firuzkuh sand (#161) _Silica sand with fine-grained content of about 1% that is known as the standard sand in Iran and has been the most widely used sand for laboratory studies_ evaluated the effects of opening width, traveling pluviator speed, fall height, and number of openings on deposition intensity and relative density. The results showed that a decrease in deposition intensity is correlated with a decrease in aperture width and an increase in traveling pluviator speed, which significantly enhances relative density. With changes in the effective parameters, a broad range of relative densities could be obtained—from 12 to 93 percent. Comparisons between the findings of the experiments revealed that double-aperture pluviation plate, given the increases in sand outlet and deposition intensity, had a density equivalent to that of single-aperture pluviation plate whit; moreover, each aperture behaved as separate, resulting in prompt sand bed preparation. The findings also revealed that increase in fall height leads to increase in relative density.