Multiplicative Watermarking Method with the Visual Saliency Model Using Contourlet Transform

We have proposed an image adaptive watermarking method by using contourlet transform. Firstly, we have selected high-energy image blocks as the watermark embedding space through segmenting the original image into nonoverlapping blocks and designed a watermark embedded strength factor by taking advantage of the human visual saliency model. To achieve dynamic adjustability of the multiplicative watermark embedding parameter, the relationship between watermark embedded strength factor and watermarked image quality is developed through experiments with the peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM), respectively. Secondly, to detect the watermark information, the generalized Gaussian distribution (GGD) has been utilized to model the contourlet coefficients. Furthermore, positions of the blocks selected, watermark embedding factor, and watermark size have been used as side information for watermark decoding. Finally, several experiments have been conducted on eight images, and the results prove the effectiveness of the proposed watermarking approach. Concretely, our watermarking method has good imperceptibility and strong robustness when against Gaussian noise, JPEG compression, scaling, rotation, median filtering, and Gaussian filtering attack.

Influencing Factors and Strategies of the Flow of Academic Professionals in Colleges and Universities Based on Convolutional Neural Networks

The influencing factors of academic professional mobility in colleges and universities are complex and diverse, and the intensity of each influencing factor has obvious characteristics of differentiation. However, scholars have few relevant studies based on the intensity of factors affecting the flow of academic professionals in colleges and universities. Therefore, this article aims to study and analyze the influence of different factors on the flow of academic professionals in different types of colleges and universities, which is of great significance for promoting the rational and orderly flow of academic professionals. This paper proposes a comprehensive application of multiple methods, such as questionnaire surveys and data statistics, based on ERG theory, based on the four types of universities and colleges: research-oriented, teaching research, teaching, and application. The influence intensity of the flow-influencing factors is comparatively studied. It clarified the differences in the influence of spiritual factors, economic factors, and social factors on the mobility of academic professionals in colleges and universities, established a mobility factor model, and put forward policy recommendations for colleges and universities to promote the rational and orderly mobility of academic professionals. A total of 2042 questionnaires on “Policy Improvement Factors Affecting the Flow of Academic Experts in Universities” were released, four academic experts of different levels were assigned to universities, and 1,561 were effectively searched. Among them, there were 336 research universities, 157 educational research universities, 404 educational universities, and 164 applied universities. The experimental results of this article show that the factors affecting the flow of academic professionals in universities include economic strength factor of 0.4945, social strength factor of 0.5456, and intellectual strength factor of 0.52. Therefore, the factors affecting the mobility of university scholars can be used in strategic research.

Improvement of Aerodynamic and Strength Characteristics of a Multi-Shaft Axial Turbine of a Turboshaft Engine

The article presents the results of solving the complex task of increasing the rotor wheel strength factor and the efficiency of the twin-shaft axial turbine of the small turboshaft engine using methods of multidisciplinary optimization. This turbine consists of a single-stage compressor turbine (CT) and a free turbine (FT). An analysis of the original variant of the turbine revealed that the strength factor of their rotor wheels are significantly lower than the necessary structural requirement. To eliminate the occurring problem at the first step the initial task of estimation the rotor wheels only on the basis of structural requirements was performed without taking into account aerodynamic processes. As a result, variants of the turbine rotor wheels were obtained to provide the structural constraints. They were used as starting points for the complex task of optimization, taking into account aerodynamic and deformation processes. The task of multi-disciplinary CT and FT optimization was solved step by step. As a first step, specific CT and FT models were built, which as a result of their optimization allowed to ensure acceptable strength factor of rotor wheel and slightly increased turbine efficiency. In the next step, a joint model of both turbines was built and tested. Its analysis showed that mutual influence of these working processes of the turbines leads to a distortion of the flow temperature distribution in the flow path, which causes a reduction of the FT blades strength criteria to an unacceptable level. Further optimization of the joint turbine model, taking into account aerodynamic and deformation processes, made it possible to increase the efficiency of both turbines by 0.4% (for each one), providing the necessary safety margins for the disks.

STRATEGI PENGEMBANGAN PRODUK KERUPUK KEMPLANG DENGAN METODE SWOT DI UMKM DUA PUTRI BUMI WARAS KOTA BANDAR LAMPUNG

The strategy of developing kemplang cracker products in Dua Putri UMKM sub-district of Bumi Waras, Bandar Lampung city is experiencing a high level of competition, the aim of this research is to produce a strategy that is in accordance with the conditions of the Dua Putri UMKM in developing a business, and to provide strategic input from the results of the research. Data collection techniques in this study were carried out by observation, interviews and questionnaires then analysed by SWOT. It is known that the IFAS value is 3,36080 with a strength factor having a value of 2.51632 and a weakness of 0.84448 with a difference in value (+) of 1.67184. and the EFAS value is 2.82229 with the opportunity factor having a value of 2.30108 and the threat factor 0.52121 with the difference in value (+) 1.77987. This value indicates that the organization is experiencing a period of growth both in sales, taste, and price differences. UMKM two putri kemplang crackers are on average in her quest to pursue a strategy of exploiting strengths to overcome weaknesses. From the results of the Cartecius diagram, that kemplang cracker Dua Putri UMKM are in quadrant 1 (one), namely an aggressive strategy, where this UMKM is in a very favorable position, this UMKM has the opportunity and strength so that it can take advantage of the existing opportunities

Features of Borehole Degassing of the Outburst-prone Coal Seams

The conditions and features are given concerning the degassing of outburst-prone coal seams by wells drilled from the underground workings in the plane of the mined seam. Technological schemes for the location of wells in the mining areas during the preparation and development of the coal seams prone to sudden outbursts of coal and gas were substantiated taking into account the coal strength determined using the method of M.M. Protodyakonov. The scheme of coal seams degassing by wells oriented to the working face line is recommended with a coal strength factor f ≥ 1.3, the degassing scheme with crossed wells — at f < 1.3. The wells are drilled parallel to the working face line and oriented to it. The schemes are implemented in the shallow mines of Karaganda (Kazakhstan), Ukraine and China. Degassing of coal seams not unloaded from the rock pressure by crossing wells ensured an increase in methane production from 1 ton of coal by 0.4–4.8 m3 in the conditions of seams with different coal strength. The highest indicators were achieved in the powerful outburst-prone seams with a coal strength factor of f = 0.3–0.8 in the conditions of the mines of Karaganda Basin, where the volumes of methane extraction by crossing wells were 5.0–5.6 m3 per ton of the degassed coal reserves in the working areas. In the conditions of the outburst-prone shallow seams of Ukraine, the volumes of methane extraction from 1 ton of the degassed coal reserves on the medium density seams amounted to 2.5–4.4 m3 with a coal strength factor of f = 0.6–1.1. 2-2.3 m3 of methane was removed from 1 ton of coal at the Dziulishan mine (China) at a strongly crushed coal layer II1 with a strength factor f = 0.3–0.6. The use of degassing schemes for gas-bearing and outburst-prone coal seams ensures an increase in the productivity of working faces and, as a result, high economic indicators.

Probability justification for a minimum margin of safety when calculating ship machine parts and endurance mechanisms

Расчеты прочности при проектировании и создании современной техники являются одним из главных критериев качества и конкурентоспособности изделий машиностроения. Неотъемлемой частью расчета прочности на выносливость является оценка минимально допустимого запаса прочности. Существующая оценка этого запаса на основе данных по отказам деталей несет в себе большую долю субъективизма. Предлагается методика определения минимально допустимого коэффициента запаса прочности. Ее принципиальное отличие от существующих заключается в том, что здесь этот коэффициент запаса прочности подсчитывается с учетом рассеяния характеристик прочности детали и действующих в ней напряжений при заданной вероятности отсутствия усталостного разрушения. Это позволяет исключить многие условности при прогнозировании прочностной надежности деталей и создает предпосылки для получения проектных решений, оптимальных по прочности и массе. Strength calculations in the design and creation of modern technology are one of the main criteria for the quality and competitiveness of engineering products. An integral part of the endurance strength calculation is the assessment of the minimum allowable margin of strength. The existing assessment of this stock, based on data on the failure of parts, carries a large share of subjectivism. It is proposed a method of determining the minimum allowable safety factor. Its fundamental difference from the existing one is that here this strength factor is calculated taking into account the scattering of the characteristics of the strength of the part and the stresses in it at a given probability of absence of fatigue destruction. This eliminates many conventions when predicting the strength of the reliability of parts and creates the prerequisites for obtaining design solutions that are optimal in strength and mass.

Shear-Dependent Yield Stress of Iron Ore Fine Tailings in Two-Step Flocculation Process

Both shear and flocculation have a significant influence on the rheological behavior of tailings, especially the yield stress. In the two-step flocculation process, the above two kinds of actions exist at the same time, and they influence each other. In order to explore the change rule of the yield stress and its internal causes, a two-step flocculation process of the iron ore fine tailings with different shear conditions in the four different phases was designed. In the primary flocculation phase, tailing particles combined with the primary flocculant and formed a primary floc network structure. In the primary broken phase, shear destroyed the primary floc network structure and decreased the average floc size, so the shear-dependent yield stress, the floc strength factor, and the fractal dimension decreased. In the secondary flocculation phase, broken floc combined with the secondary flocculant and produced a more compact floc network structure which had a better shear resistance. Therefore, in the secondary broken phase, with the increase of shear, the decrease of yield stress, the floc strength factor, and fractal dimension were less obvious than that in the primary broken phase. In both two broken phases, the yield stress of the secondary flocculating slurry was always higher than that of the primary flocculating slurry, but with the increase of shear, the difference became smaller. The floc strength and fractal dimension also showed the same rule. The internal reasons for the stronger shear resistance of the secondary flocculating slurry were the increase of the number of binding sites, the electric neutralization between the two flocculants, and the steric hindrance effect of the flocculants.

STRATEGI PENGEMBANGAN USAHA KERAJINAN PERAK DENGAN METODE ANALISIS SWOT PADA USAHA SSS SILVER

The purpose of this research is to find out the dominant factors of strengths, weaknesses, opportunities and threats to SSS Silver's silvercraft business in running its business and determine marketing strategies that can be applied to SSS Silver silvercraft business in order to grow its business. The number of respondents who were the management of SSS Silver who sampled the research was 3 people. The analysis technique used is SWOT analysis. The results of this study show that the dominant internal factor affecting SSS Silver's silver craft business in running its company's operations is the strength factor, while the dominant external factor is the business opportunity factor that SSS Silver has. Based on the results of SWOT analysis, the right strategy used by SSS Silver silvercraft business is so strategy model that is a strategy that uses strength and by utilizing opportunities (Opportunies). Keywords: silver craft, development strategy, SSS Silver, SWOT.