scholarly journals Ellipsometric Study of the Zinc Selenide Natural Cleaves Oxidation

2015 ◽  
Vol 16 (3) ◽  
pp. 481-486
Author(s):  
V. А. Оdarych

Measuring of ellipsometric parameters of the light reflected from the fresh cleaves surface of zinc selenide  are conducted under atmospheric conditions during one year. It has been found that the process of cleaves surface interaction with air consists of two stages. A layer with  thickness to 7 nm is formed on the first stage within  to 3 weeks. This layer optical constants  are a little less than zinc selenide optical constants. An external transparent layer with the index of refraction approximately 1,4 and thickness to 2,5 nm show itself on the second stage from one month of to year. Supposed, this external layer contains the mixture of an unstable oxides and air.

2012 ◽  
Vol 42 (1) ◽  
pp. 3-22 ◽  
Author(s):  
Alexander Kazakoff

Advances in Engineering Software for Lift Transportation Systems In this paper an attempt is performed at computer modelling of ropeway ski lift systems. The logic in these systems is based on a travel form between the two terminals, which operates with high capacity cabins, chairs, gondolas or draw-bars. Computer codes AUTOCAD, MATLAB and Compaq-Visual Fortran - version 6.6 are used in the computer modelling. The rope systems computer modelling is organized in two stages in this paper. The first stage is organization of the ground relief profile and a design of the lift system as a whole, according to the terrain profile and the climatic and atmospheric conditions. The ground profile is prepared by the geodesists and is presented in an AUTOCAD view. The next step is the design of the lift itself which is performed by programmes using the computer code MATLAB. The second stage of the computer modelling is performed after the optimization of the co-ordinates and the lift profile using the computer code MATLAB. Then the co-ordinates and the parameters are inserted into a program written in Compaq Visual Fortran - version 6.6., which calculates 171 lift parameters, organized in 42 tables. The objective of the work presented in this paper is an attempt at computer modelling of the design and parameters derivation of the rope way systems and their computer variation and optimization.


Author(s):  
Yaru Guo ◽  
Tian-Chyi Jim Yeh ◽  
Yonghong Hao

Globally karst aquifers store large amount of precious water and create beautiful karst springs in many places. However, most of the karst springs flow declined, and some of the karst springs dried up with the effects of extensive groundwater development and climate variation. For example, Jinci Springs (China) is known for the beautiful landscape it created and large area of paddy fields it irrigated. Unfortunately, it dried up in May 1994. For better understanding of the hydrological processes of karst springs, this study introduced grey system models to quantify spring flow taking Jinci Springs as an example. Based on the characteristics of Jinci Springs flow, the spring flow was divided into two stages: the first stage (1954-1960), when the spring flow was affected only by climate variation; and the second stage (1961-1994), when the flow was impacted by both climate variation and anthropogenic activities. Results showed that the Jinci Springs flow had strong relations with precipitation occurring one year and three years earlier in the first stage. Subsequently, a grey system GM (1, 3) model with one-year and three-year lags was set up for the first stage. By using the GM (1, 3) model, we simulated the spring flow in the second stage under effects of climate variation only. Subtracting the observed spring flow from the simulated flow, we obtained the contribution of anthropogenic activities to Jinci Springs cessation. The contribution of anthropogenic activities and climate variation to Jinci Springs cessation was 1.46m3/s and 0.62m3/s, respectively. Finally, each human activity causing spring flow decline was estimated.


Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1927
Author(s):  
Yaru Guo ◽  
Tian-Chyi Jim Yeh ◽  
Yonghong Hao

Karst aquifers are prominent sources of water worldwide; they store large amounts of water and are known for their beautiful springs. However, extensive groundwater development and climate variation has resulted in a decline in the flow of most karst springs; some have even dried up. In order to obtain a better understanding of the factors contributing to this development, this study introduced grey system models, which quantified spring flow, taking Jinci Springs (China), which dried up in May 1994, as an example. Based on the characteristics of Jinci Springs, spring flow was divided into two stages: first (1954–1960), when the spring flow was affected only by climate variation; and second (1961–1994), when the flow was impacted by both climate variation and anthropogenic activities. The results showed that Jinci Springs flow had a strong relationship with precipitation occurring one year and three years earlier in the first stage. Subsequently, a grey system GM (1,3) model with one-year and three-year lags was set up for the first stage. By using the GM (1,3) model, we simulated the spring flow in the second stage under effects of climate variation only. By subtracting the observed spring flow from the simulated flow, we obtained the contribution of anthropogenic activities to Jinci Springs’ cessation. The contribution of anthropogenic activities and climate variation to the decline was 1.46 m3/s and 0.62 m3/s, respectively. Finally, each human activity that caused the decline was estimated. The methods devised herein can be used to describe karst hydrological processes that are under the effects of anthropogenic activities and climate variation.


Author(s):  
Dale E. Bockman ◽  
L. Y. Frank Wu ◽  
Alexander R. Lawton ◽  
Max D. Cooper

B-lymphocytes normally synthesize small amounts of immunoglobulin, some of which is incorporated into the cell membrane where it serves as receptor of antigen. These cells, on contact with specific antigen, proliferate and differentiate to plasma cells which synthesize and secrete large quantities of immunoglobulin. The two stages of differentiation of this cell line (generation of B-lymphocytes and antigen-driven maturation to plasma cells) are clearly separable during ontogeny and in some immune deficiency diseases. The present report describes morphologic aberrations of B-lymphocytes in two diseases in which second stage differentiation is defective.


2020 ◽  
Vol 39 (6) ◽  
pp. 8139-8147
Author(s):  
Ranganathan Arun ◽  
Rangaswamy Balamurugan

In Wireless Sensor Networks (WSN) the energy of Sensor nodes is not certainly sufficient. In order to optimize the endurance of WSN, it is essential to minimize the utilization of energy. Head of group or Cluster Head (CH) is an eminent method to develop the endurance of WSN that aggregates the WSN with higher energy. CH for intra-cluster and inter-cluster communication becomes dependent. For complete, in WSN, the Energy level of CH extends its life of cluster. While evolving cluster algorithms, the complicated job is to identify the energy utilization amount of heterogeneous WSNs. Based on Chaotic Firefly Algorithm CH (CFACH) selection, the formulated work is named “Novel Distributed Entropy Energy-Efficient Clustering Algorithm”, in short, DEEEC for HWSNs. The formulated DEEEC Algorithm, which is a CH, has two main stages. In the first stage, the identification of temporary CHs along with its entropy value is found using the correlative measure of residual and original energy. Along with this, in the clustering algorithm, the rotating epoch and its entropy value must be predicted automatically by its sensor nodes. In the second stage, if any member in the cluster having larger residual energy, shall modify the temporary CHs in the direction of the deciding set. The target of the nodes with large energy has the probability to be CHs which is determined by the above two stages meant for CH selection. The MATLAB is required to simulate the DEEEC Algorithm. The simulated results of the formulated DEEEC Algorithm produce good results with respect to the energy and increased lifetime when it is correlated with the current traditional clustering protocols being used in the Heterogeneous WSNs.


Author(s):  
Fitriah Khoirunnisa ◽  
Friska Septiani Silitonga ◽  
Veri Firmansyah

Penelitian ini bertujuan menganalisis kebutuhan petunjuk praktikum berbasis Keterampilan Proses Sains (KPS) untuk mencapai kemampuan merancang eksperimen pada materi kalor reaksi kalorimetri. Penelitian dilakukan terhadap peserta didik kelas XI SMA Negeri 2 Kota Tanjungpinang. Variabel penelitian mencakup analisis kebutuhan bahan ajar dan analisis kesesuaian Kompetensi Inti (KI) dan Kompetensi Dasar (KD). Jenis penelitian yang dilakukan adalah penelitian deskriptif kualitatif. Tahapan pertama dalam penelitian ini adalah menganalisis kebutuhan bahan ajar dengan cara membandingkan dua petunjuk praktikum yang selama ini telah digunakan di sekolah tersebut, ditinjau dari aspek struktur format penulisan, aspek kreativitas, dan aspek keterampilan proses sains yang terdapat dalam petunjuk praktikum. Sehingga didapatkan kesimpulan bahwa petunjuk praktikum yang selama ini digunakan tidak memberikan kesempatan kepada peserta didiknya untuk merancang eksperimen yang telah ditentukan. Tahapan kedua yaitu menganalisis kesesuaian kompetensi inti dan kompetensi dasar, yang bertujuan untuk menentukan indikator pencapaian kompetensi (IPK) yang akan menjadi acuan dalam mengembangkan petunjuk praktikum berbasis keterampilan proses sains. Dari kedua tahapan yang telah dilakukan maka dapat disimpulkan bahwa peserta didik memerlukan petunjuk praktikum yang mampu mengonstruksi pikiran dan mengaktifkan kinerja mereka, sehingga pendekatan Keterampilan Proses Sains menjadi pilihan dalam mengembangkan petunjuk praktikum yang sesuai dengan karakteristik kurikulum 2013.   This research aims to analyze the needs of Science Process Skills based Practical Instruction to achieve the ability to design experiments on the calor of reaction. This research was done to the students of class XI SMA Negeri 2 Tanjungpinang City. Research Variable includes the analysis of the needs of the learning materials and analysis of the suitability of the Core Competence (KI) and Basic Competence (KD). The type of research conducted is descriptive qualitative research. The first stages in this research is to analyze the needs of learning materials by comparing two practical instructions that had been implementing in the school, from the aspects of the structure of writing format, creativity, and science process skills embedded in practical instructions. The conclusion of this research that current practical instructions does not give an opportunity to the participants to design determined experiments. The second stage, namely analyzing the suitability of core competence and basic competence, which aims to determine the indicators of achievement of the competencies (GPA) which will be a reference in developing process skills-based teaching instructions science. Of the two stages that has been done then it can be concluded that learners need practical instructions to construct  thinking and and their performance, so the Science Process Skills approach is an option in developing practical instruction suitable for the characteristics of the curriculum of 2013.


2014 ◽  
Vol 59 (1) ◽  
pp. 41-52 ◽  
Author(s):  
Norbert Skoczylas

Abstract The Author endeavored to consult some of the Polish experts who deal with assessing and preventing outburst hazards as to their knowledge and experience. On the basis of this knowledge, an expert system, based on fuzzy logic, was created. The system allows automatic assessment of outburst hazard. The work was completed in two stages. The first stage involved researching relevant sources and rules concerning outburst hazard, and, subsequently, determining a number of parameters measured or observed in the mining industry that are potentially connected with the outburst phenomenon and can be useful when estimating outburst hazard. Then, the Author contacted selected experts who are actively involved in preventing outburst hazard, both in the industry and science field. The experts were anonymously surveyed, which made it possible to select the parameters which are the most essential in assessing outburst hazard. The second stage involved gaining knowledge from the experts by means of a questionnaire-interview. Subjective opinions on estimating outburst hazard on the basis of the parameters selected during the first stage were then systematized using the structures typical of the expert system based on fuzzy logic.


2017 ◽  
Vol 924 (6) ◽  
pp. 6-16
Author(s):  
V.S. Tikunov ◽  
O.Yu. Chereshnia

The article presents a methodology for a comprehensive assessment of the environmental situation in Russian Federation regions based on the pollution index and the index of the ecological tension. The evaluation was carried out in two stages. At the first stage, the degree of pollution of the atmosphere, hydrosphere and lithosphere of the regions was estimated on the basis of the emission of pollutants into the atmosphere, departing from stationary sources, the formation of solid domestic wastes (SDW) and the discharge of contaminated wastewater. Based on these three indicators, a pollution index was constructed that estimates aggregate pollution level. In the second stage, the authors made the estimation of loads generated by atmospheric emissions, solid waste and waste water discharged into the territory of each region, per capita and in relation to the environmental capacity of the economy. This allows us to take into account the area of pollution, anthropogenic pressure and environmental responsibility of the population, as well as the environmental friendliness of production. On the basis of relative indicators, the index of ecological tension was created.


2021 ◽  
Vol 11 (2) ◽  
pp. 57
Author(s):  
Roksana Binte Rezwan ◽  
Yoshi Takahashi

This study aimed to understand the psychological process behind employees’ knowledge hiding (KH) behaviors in organizations. KH is an intentional act of concealing knowledge when it is requested by a colleague and can lead to counterproductive consequences for the organization. Therefore, this study synthesized previous studies (n = 88) on KH through a systematic literature review. We used the cognitive–motivational–relational (CMR) theory of emotion to create a framework for the studies’ findings. Based on the framework, the psychological process behind KH has two stages—personal goal generation and the knowledge-request event appraisal process, each of which contains its own CMR process. In the first stage, an individual’s internal and external attributes related to the organization shape their personal goals. In the second stage, an individual appraises the features of a knowledge-request event in terms of both their personal goal and the internal and external attributes that created the goal. If the knowledge request is appraised as harmful for the personal goal, emotion arises and leads to the manifestation of KH. This study contributes to the knowledge management literature as, to our knowledge, it is the first to propose a CMR theory-based framework to understand the overall psychological process behind KH.


2021 ◽  
pp. 105971232110310
Author(s):  
Charles Lenay

The aim of this article is to offer a new approach of perception regarding the position of a distant object. It is also a tribute to John Stewart who accompanied the first stages of this research. Having already examined the difficulties surrounding questions of the perception of exteriority within the framework of enactive approaches, we will proceed in two stages. The first stage will consist of an attempt to explain distal perception in terms of individual sensorimotor invariants. This poses the problem but fails to solve it. The second stage will propose a new pathway to account for spatial perception; a pathway that does not deny the initial intuitions of the autopoietic enactive approaches, but one which radically changes the conception of cognition by considering, from the perceptual stage, the need to take into account interindividual interactions. The protocol of an original experimental study will characterize this new approach considering the perceptual experience of objects at a distance, in exteriority, in a space of possibilities without parting from the domain of interaction. To do this, we have to work at the limits of the perceptual crossing, that is, at the moment when the perceptual reciprocity between different subjects begins to disappear.


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