Invisibility is one of the aspirations of human beings that the optics and materials have made, and metamaterials make this achievable. Metamaterials have amazing optical properties, including a negative refractive index, which are not found in nature and must be prepared with special techniques. Normally, the light that hits an opaque object is reflected from it and becomes visible. Metamaterials transform this two-way relationship between light and objects so that the light changes its direction around the object without being reflected and passing through it. In this case, the object becomes invisible because no light is visible. In this article, general information about how objects become invisible and methods of preparing metamaterials will be presented by using the principles of light physics and explaining the phenomena of light refraction and surface plasmon.

Study the titles of body organs as well as counting them in the anatomical texts of humoural medicine indicates an important issue: in these texts and in comparison with modern anatomical texts, there is no mention of a significant number of body organs. This is while these two different conclusions are the result of the observations of the same action: the dissection of the corpse. In addition, some of these organs are visible to the naked eye, including lymphatic vessels. Therefore, the humoural physician has seen some organs in the process of dissection, but has not. According to the authors of this article, the reason for the Invisibility of these organs lies in the connection between observation and theory. In short, the observation of the humoural physician's dissection practice, unlike the observation of the modern anatomist dissection practice, has been based on the humoural theory. Hence, the humoural physician, in the process of dissection, has seen organs which have a humoural function. The rest of the body organs were either not seen or reduced to a fleshy appendages.

Photonic crystals are structures that can control the propagation of light by creating periodic changes in the refractive index. These structures facilitate directing electromagnetic waves in specific directions and making objects invisible by creating a bandgap. Photonic crystals, as microscopic structures with unique optical properties, are used in the design of Invisibility systems. However, the design and optimization of these structures, especially with new methods like deep learning, have not been thoroughly investigated. Utilizing deep learning techniques can be highly beneficial in this area. Therefore, this paper employs the deep neural network architecture ResNet to optimize photonic crystals. ResNet can assist designers in selecting suitable materials and determining the optimal dimensions and arrangements of photonic nanostructured crystals for Invisibility by extracting complex and nonlinear features from input data. The phenomenon of negative refraction in photonic crystals and the way light propagates in the proposed Invisibility were studied using FDTD simulation. The results indicated that appropriate design of photonic crystals using deep learning could contribute to the creation of efficient structures.

Plasmonic cloaking is one of the Invisibility methods which is very attractive for researchers. Despite of non-perfect nature of this method there are some advantages such as easier practical realization for it. In this paper, considering cylindrical layered metamaterial with composition of graphene and TiO2 layers, wave equation is solved for this structure analytically. After calculating scattering cross section, Invisibility condition is investigated in the structure. Then, the effect of changing in some geometrical and physical parameters such as chemical potential, core radius and number of layers on Invisibility condition is analyzed. Some numerical simulation using COMSOL approve the results.

The main purpose of this article is to use metasurfaces to make objects invisible. The process is that, after examining how to analyze the electromagnetic plan metasurface of the plate, a method for the analysis of cylindrical metasurfaces is presented. Then, inspired by the modeling of plan metasurfaces, a method based on the physical characterization of cylindrical metasurfaces in order to model and extract their tensor parameters is expressed. The methods presented in this paper for analyzing, modeling and extracting the parameters of cylindrical metasurfaces can be implemented for any desired type of linear metasurfaces in a wide frequency range consisting of radio and microwave waves to light waves. In the next step, the proposed formulation is used to reduce the scattering of electromagnetic waves from objects or so-called Invisibility. The proposed method for Invisibility makes it possible to provide different configurations of metasurfaces to achieve any type of Invisibility according to the limitations of practical implementation. In addition, the formulation is effective in providing a physical understanding and description of Invisibility. To test the results, the formulation of this paper was applied to a designed metasurface sample. Finally, with the help of full-wave simulations, the metasurface tensor parameters are extracted and the desired Invisibility is realized.

This paper presents a mantle cloak structure to provide a wideband capability to hide a metallic cylinder over a broad span of angles of obliquely impinging plane waves. A bi-layered dielectric structure and a sheet of metasurface are used to enclose the object to be hidden. At first, the scattered field, including co- and cross-polarized components, is analytically formulated using circumferential waves for a multi-layer wrap around the cylinder. A tensor description is also applied to model the impedance of the metasurface for TE and TM waves. Then, a metasurface made of rectangular patches is considered, and its related parameters are optimized to hide a perfect electric conductor (PEC) cylinder. Moreover, a double-layered mantle cloak is presented and numerically investigated using a software package to enhance its cloaking bandwidth. The numerical results show that the clocking bandwidth is enhanced by up to 33% compared to that of a single-layered structure.

Relying on the distinction between two key cultural strategies of foreignization and domestication postulated by Venuti, this research explores the way in which foreign literature has been portrayed in Persian context. To this end, three world famous novels originally written in English are compared with their Persian translations. The outlet of the research is based on the solid foundation of the practical models of translation that have been gleaned from a number of studies. This product-oriented descriptive translation research is a qualitative attempt to describe and analyse the applied foreignization and domestication procedures. The research questions aims to explore the dominant strategy in the dichotomy of foreignizationl domestication as well as the scope of application of these two strategies in the corpus of the research. According to the obtained results, domestication has been introduced as the most pervasive cultural translation strategy applied in the corpus of the research as well as each ST-TT pair.

Although Iranian government organizations suffer from excessive manpower, they are not adequately effective and are not capable of fulfilling their essential missions. In other words, invisible employees have become the dominant phenomenon of today's governmental organizations. Many factors have contributed to the ineffective use of manpower, including bureaucratic culture and passive leadership. This research project studied the effect of bureaucratic culture on the Invisibility of employees with the mediating role of passive leadership in governmental organizations of Lorestan province. This cross-sectional, descriptive– correlational study is applied in terms of purpose. The statistical population of the study was comprised of 1317 employees of different governmental organizations of Lorestan province. Based on the Morgan table, a sample of 297 employees was selected using stratified random sampling. In order to measure the variables of the research, Denison’ s bureaucratic culture questionnaire (1990), Brian and Holtz’ s passive leadership questionnaire (2017), and the invisible employee questionnaire by Mohammad Yari et al. (2018) were used. The reliability of the questionnaires was confirmed by Cronbach's alpha, and then the structural equation modeling in PLS software was used for data analysis. The results of the study showed that bureaucratic culture, both directly and through passive leadership, leads to the Invisibility of employees in government organizations of the Lorestan province.

Pteridium aquilinum which wildly could be found in different continents, is common in Hycanian region of Iran. This weeds species can cause problems in rangeland, agriculture and forest management. As this species is encroaching into mountainous rangelands, this study assesses the P. aquilinum presence and its edaphic niches in summer rangelands of Bandpay, Babol, Mazandaran province, Iran. The vegetation cover, density, height, and biomass besides the soil were sampled in four invaded sites including forest, two shrublands, and one grassland. The results showed that the species had a mean cover of 50 to 75%, mean density of 12 to 37 stands/m2, mean stand height of 50 to 90 cm, and mean above-ground biomass of 4 to 7 tons/ha. All measured variables in invaded grasslands except frond height were significantly greater than that in invaded shrublands and forest. Invaded areas had significantly greater organic matter, N, and EC and less pH than that in not invaded rangelands. P. aquilinum showed an optimum in acidic soil with high moisture. Control of this species should be a part of management otherwise the spread of this species could lead to further land abandonment.