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Copyright of Journal of Petroleum Research & Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mishrif formation is the main carbonate reservoir in southern Iraq, which is extremely heterogeneous and require accurate geological description for optimal oil field development. This research is associated with developing a representative 3D static model that conserves geological elements and relieves the uncertainty of reservoir properties and volumetric estimates. The interpreted log data and core reports were selected to capture all structural, stratigraphical and petrophysical properties. The reservoir is discretized with irregular cells using the tartan grid, concentrating their accuracy in important areas. A sequential Gaussian simulation algorithm distributed the petrophysical properties for all reservoir units. The structural model showed that Mishrif reservoir in Garraf oil field has a domal structure with two main producing reservoirs (M1.2 and L1.2). The petrophysical model results present that unit L1.2 has high-quality properties with average porosity of 0.24 and water saturation of 0.17 and less than in unit M1.2, where the average water saturation and porosity are 0.47 and 0.185, respectively. The estimated oil in place with the volumetric method was 901 Million standard cubic meters, most of which accumulated in unit L1.2. This study was applied to reappraise the reserves of Mishrif reservoir in Garraf oil field using irregular gridding. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Japan Forest Engineering Society is the property of Japan Forest Engineering Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In vitro digestion models for assessing the bioaccessibility of lipophilic compounds from foodstuffs can either be static or dynamic. Carotenoids are the most widely studied compounds, while there is hardly any information on sterols and fat-soluble vitamins available, nor on the use of dynamic methods. There is a large variability in the parameters of static methods, which makes data comparison difficult. To harmonize digestion conditions and compare bioaccessibility, INFOGEST model has been established. This review assesses the most relevant digestion methods (non-INFOGEST, INFOGEST and dynamic) applied to carotenoids, sterols, and fat-soluble vitamins in food matrices in the last ten years. [ABSTRACT FROM AUTHOR]

The advent of the era of big data has had an important impact on the education mode, education management methods, and education thinking paths of college ideology and politics. In this paper, an innovative platform for the theoretical practice of ideological and political education based on the background of big data is constructed by a B/S (browser/server) architecture system, which first accesses the server database and executes the application. Secondly, UML (Unified Modeling Language) modeling is established, and static and dynamic modeling are used to realize the use of distance learning systems. Finally, the important branches of FCM algorithm modeling are applied to optimize the problem using cluster transformation, and the system is examined for data. The results show that the platform constructed in this paper can make students’ awareness of teaching contents reach 75%, attention reach 53%, the overall effect of teaching reach 88%, and the average value of online examination score is 7.2 in the teaching system. Thus, the platform constructed in this paper can help promote the theoretical practice of ideological and political education in colleges and universities and can better propose new ideas and methods for ideological and political education.

The Bleve is an explosion involving both the rapid vaporization of liquid and the rapid expansion of vapor in a vessel. The loss of containment results in a large fireball if the stored chemical is flammable. In order to predict the damage generated by a Bleve, several authors propose analytical or semi-empirical correlations, which consist in predicting the diameter and the lifetime of the fireballs according to the quantity of fuel. These models are based on previous experience, which makes their validity arbitrary in relation to the initial conditions and the nature of the product concerned. The article delves into uncertainty analysis associated with analytical and semi-empirical models of the BLEVE fireball. It could explore how uncertainties in input data, and the choice of a more or less inappropriate model, propagate into the model results. Statistical techniques such as global sensitivity analysis or uncertainty analysis are employed to quantify these uncertainties. In this paper, an attempt is made to evaluate and select reasonable models available in the literature for characterizing fireballs and their consequences. Correlations were analyzed using statistical methods and BLEVE data (experimental and estimated data by correlation) to determine the residual sum of squares (RSS) and average absolute deviation (AAD). Analysis revealed that the Center for Chemical Process Safety (CCPS), the TNO (Netherlands Organization for Applied Scientific Research), and the Gayle model revealed a high degree of satisfaction between the experimental and estimated data through correlation. [ABSTRACT FROM AUTHOR]

This article presents a generalizable, low computational cost, simple, and fast gravity compensation method for legged robots with a variable number of legs. It is based on the static problem, which is a reduction in the dynamic model of the robot that takes advantage of the low velocity of climbing robots. To solve it, we propose a method that computes the torque to be applied by each actuator to compensate for the gravitational forces without using the Jacobian matrix for the forces exerted by the end-effector and without using analytical methods for the gravitational components of the model. We compare our method with the most popular method and conclude that ours is twice as fast. Using the proposed gravity compensator, we present a torque-based PD controller for the position of the leg modules, and a body velocity control without dynamic compensation. In addition, we validate the method with both hardware and a simulated version of the ROMERIN robot, a modular legged and climbing robot. Furthermore, we compare our controller with the usual kinematic inverse controllers, demonstrating that the mean angular and linear error is significantly reduced, as well as the power requirements of the actuators. [ABSTRACT FROM AUTHOR]

The 3D static reservoir modelling provides a good understanding for the hydrocarbon reservoir distribution and properties. This study aimed to construct a static model to study the gas-reservoir potentiality of the Messinian Abu Madi Formation in Baltim Field, offshore Nile Delta Basin. This model was constructed based on the interpretation of the thirty-seven 2D seismic sections besides the analysis of well logs data for five drilled wells (Baltim East-2, Baltim East-3, Baltim East-5, Baltim North-1 and Baltim North-2). The seismic interpretation exposed that the Abu Madi incised valley in Baltim Field is oriented NNW-SSE with width ranges from 5 to 8 km and approximately 32 km in length. The reservoir modelling revealed a relatively homogeneous reservoir facies qualities for gas production in two different zones within the Abu Madi sandstones. The trapping mechanism for these intervals is represented by pinching out in the two sides of the Abu Madi paleo-valley and bounded by two faults in the northern and southern parts of the study area.

The purpose of this study is to analyze the contribution of the interactions between electrodes, measured either as correlation or as Jaccard distance, to the classification of two actions in a motor imagery paradigm, namely, left-hand movement and right-hand movement. The analysis is performed in two classifier models, namely, a static (linear discriminant analysis, LDA) model and a dynamic (hidden conditional random field, HCRF) model. The impact of using the sliding window technique (SWT) in the static and dynamic models is also analyzed. The study proved that their combination with temporal features provides significant information to improve the classification in a two-class motor imagery task for LDA (average accuracy: 0.7192 no additional features, 0.7617 by adding correlation, 0.7606 by adding Jaccard distance; p < 0.001) and HCRF (average accuracy: 0.7370 no additional features, 0.7764 by adding correlation, 0.7793 by adding Jaccard distance; p < 0.001). Also, we showed that adding interactions between electrodes improves significantly the performance of each classifier, regarding the nature of the interaction measure or the classifier itself.

Continuum robots are often used as wrist joints in medical robots because of their high dexterity and flexibility. Especially, the notched continuum robot (NCR) is used in the miniaturized wristed surgical robot. The Piecewise Constant Curvature (PCC) assumption is often used in the design of NCR. However, due to the friction effect, ideal PCC is difficult to achieve. Static analysis is a necessary means to correct the curvature of NCR. The static modeling of NCR is often based on the theory of small deformation. However, this cannot obtain accurate solutions at large bending angles. In this paper, a static model of a triangular-notched continuum robot is proposed. It presents a curvature correction method of NCR, considering large deformation. In addition, the friction effect is considered in the correction of PCC. The static model is derived from the end notch. Based on the Coulomb friction model, the recurrence relationship of the force on the cable is obtained. Then the elliptic integral solution corresponding to the large deformation assumption is calculated. The deformation parameters of the NCR are obtained by numerical iteration. Finally, the capability and validity of the static model proposed in this paper are verified in the experiment. This paper is of great significance for establishing an accurate static model for curvature correction and design of the notched continuum robot. [ABSTRACT FROM AUTHOR]

In this work, an analytical method for finding the equilibrium configuration of the suspension systems used for the non-steered (usually rear) wheels of the passenger car is proposed. This study is based on the static model, which takes into account the elastic elements of the suspension (springs, bushings, anti-roll bar, buffers). The external loading of the suspension system comes from the contact forces between the wheels and the ground, depending on the specific operating regime of the vehicle (static or dynamic, by case). An algorithm for analysis of the relative movements in the wheel guiding mechanisms was developed (and further integrated in the general method for finding the equilibrium position) with the purpose of establishing the deformations of the elastic elements. Finally, a computer program was conceived and tested on a particular application. [ABSTRACT FROM AUTHOR]

Based on the anti-parallelogram mechanism, an approximate cylindrical rolling joint is proposed to develop a novel cable-driven snake-arm robot with multiple degrees of freedom (DOF). Furthermore, the kinematics of the cable-driven snake-arm robot are established, and the mapping between actuator space and joint space is simplified by bending decoupling motion in the multiple segments. The workspace and bending configurations of the robot are obtained. The static model is established by the principle of minimum potential energy. Furthermore, the simplified cable constraints in the static model are proposed through Taylor expansion, which facilitates the equilibrium conformation analysis of the robot under different external forces. The cable-driven snake-arm robot prototype is developed to verify the feasibility of the robot design and the availability of the static model through the experiments of the free bending motion and the external load on the robot. [ABSTRACT FROM AUTHOR]

Simulation tools are essential to design the infrastructure and plan the trains operations of electrical railway systems. Traditionally, the train model (that estimates the electrical, mechanical and kinematical behaviors of the vehicles) and electrical network model (that estimates the electrical behavior of the energy supply network) are developed separately. Then, they are simulated together to estimate the interactions between both subsystems. The paper objective is to compare different models to highlight the impacts on the interactions between the vehicles and the railway electrical network, which are crucial to have accurate estimations of the system behavior. For this purpose, a new dynamical model, which is based on a systemic approach and a causality analysis, is compared to a conventional static model, which is based on a cartesian approach and a power flow analysis. The dynamical model is accurate and has been experimentally validated but requires a long computational time. The static model is fast to compute and give a good estimation of the energy consumption for conventional railway systems. However, it is not always able to estimate the power flows within the DC network, and especially when all traction power substations are blocked. [ABSTRACT FROM AUTHOR]

Due to their exceptional performance in coping with large variations in output voltage and current, parallel resonant converters (PRC) are commonly used in high-voltage applications. The incorporation of step-up transformer parasitic components as part of a power topology, on the right duty and a suitable switching frequency, determines the high efficiency and wide variety of applications with PRC. Switching losses are reduced in the same topology by tracking and running on the optimum mode for each power and voltage by a set frequency and duty. The PRC's static model behaviors, under optimum operating circumstances, are illustrated. The equivalent polynomial model is used to quickly compute the switching frequency and duty cycle required to achieve the converter's desired output voltage and power. The polynomial model is simple and easy to implement in any form of a digital signal controller (DSC). Normalized parameters are used to widen the operational range and generalize the model. This also offers the essential protection against current and voltage spikes. The work in progress depicts the specific procedures involved in developing a polynomial model. The normalized equations provide a graphical description of the static model, from which the graphical representation of the polynomial are derived. Hence, polynomial equations are obtained. This paper describes the PRC static model, how to convert it to a polynomial model, how to validate it with MATLAB-Simulink, how to program F28335 using Simulink, and how to use it in practice. [ABSTRACT FROM AUTHOR]

Research on capital structure, recently characterized by the use of dynamic capital structure. The use of dynamic capital structure basically wants to know the existence of optimal leverage as hypothesized by Trade-Off Theory and Speed off Adjustment (SOA) to optimal leverage. This research tries to overcome this problem, by using dynamic panel data by using company characteristics and macroeconomic factors. The use of General Method of Moment (GMM) to overcome the problem of econometrics due to the use of dynamic models. Samples taken from manufacturing companies listing on the Indonesia Stock Exchange 2009-2015. The inference model and the determinant behavior of capital structure can be explained by Trade-Off Theory and Pecking Order Theory. The variable characteristics of the company and macro economy are significant and are marked according to the hypothesis. The findings of this study include: the influence of profitability, size, tangibility, growth opportunity and business risk. In addition, on average companies in Indonesia can increase their debt to utilize tax shields

Coke oven gas (COG) dome injection in COREX melter gasifier is recognized as one of effective method to reduce the amount of solid fuel used for gasification. In this work, a static model was developed to study the characteristics when COG is injected from dome. The critical bosh gas and critical fuel rate in COREX melter gasifier under different melting rate and coke rate were discussed. The amount of COG injection from dome under the critical fuel rates was studied. The results shows that when the heat of bosh gas reaching the critical value, the decrement of fuel rate decreases with the increase of melting rate and increases with the increase of coke rate. Under the critical fuel rate, the total volume of COG increases with the increase of melting rate and coke rate. After the COG injection, the amount and reduction capacity of the generator gas can meet the needs of reduction in shaft furnace. The findings of this work can be used as a theoretical basis to guide plant operations for COG injection.

Continuum robots are often used as wrist joints in medical robots because of their high dexterity and flexibility. Especially, the notched continuum robot (NCR) is used in the miniaturized wristed surgical robot. The Piecewise Constant Curvature (PCC) assumption is often used in the design of NCR. However, due to the friction effect, ideal PCC is difficult to achieve. Static analysis is a necessary means to correct the curvature of NCR. The static modeling of NCR is often based on the theory of small deformation. However, this cannot obtain accurate solutions at large bending angles. In this paper, a static model of a triangular-notched continuum robot is proposed. It presents a curvature correction method of NCR, considering large deformation. In addition, the friction effect is considered in the correction of PCC. The static model is derived from the end notch. Based on the Coulomb friction model, the recurrence relationship of the force on the cable is obtained. Then the elliptic integral solution corresponding to the large deformation assumption is calculated. The deformation parameters of the NCR are obtained by numerical iteration. Finally, the capability and validity of the static model proposed in this paper are verified in the experiment. This paper is of great significance for establishing an accurate static model for curvature correction and design of the notched continuum robot.

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, the demand function of drinkable water in Qazvin Province was estimated using dynamic and static methods. The required data were collected from the data of the provinces of Qazvin in the time period (1996-2016) and collected by referring to the statistical system of Statistics Center of Iran and the provincial planning and budget organization of Qazvin Province. The explanatory variables used in the model include household income, temperature (minimum and maximum), urban population, water price, rainfall, number of subscribers.The method used to estimate the static model, generalized least squares, and in the dynamic model, is a two-step generalized moment method. The results showed that the water price coefficient in the static and dynamic model is -0.217 and -0.19, respectively, which is a negative sign of the correctness of the demand law and less than one indicative of the low elasticity of water. The variable coefficient of household income in the static and dynamic model was 0.2 and 0.15, respectively, which positive and less than one, respectively, indicating the normality and necessity of water in the drinkable sector. In relation to the price of other goods, the coefficient was estimated in both negative models were -0.72 and -0.9, respectively, which indicates that water is a complementary product. Finally, the value of the variable coefficient was 0.5, which indicates that the demand for water is 0.5 times the demand for water last year.

In this work, an analytical method for finding the equilibrium configuration of the suspension systems used for the non-steered (usually rear) wheels of the passenger car is proposed. This study is based on the static model, which takes into account the elastic elements of the suspension (springs, bushings, anti-roll bar, buffers). The external loading of the suspension system comes from the contact forces between the wheels and the ground, depending on the specific operating regime of the vehicle (static or dynamic, by case). An algorithm for analysis of the relative movements in the wheel guiding mechanisms was developed (and further integrated in the general method for finding the equilibrium position) with the purpose of establishing the deformations of the elastic elements. Finally, a computer program was conceived and tested on a particular application.

Based on the anti-parallelogram mechanism, an approximate cylindrical rolling joint is proposed to develop a novel cable-driven snake-arm robot with multiple degrees of freedom (DOF). Furthermore, the kinematics of the cable-driven snake-arm robot are established, and the mapping between actuator space and joint space is simplified by bending decoupling motion in the multiple segments. The workspace and bending configurations of the robot are obtained. The static model is established by the principle of minimum potential energy. Furthermore, the simplified cable constraints in the static model are proposed through Taylor expansion, which facilitates the equilibrium conformation analysis of the robot under different external forces. The cable-driven snake-arm robot prototype is developed to verify the feasibility of the robot design and the availability of the static model through the experiments of the free bending motion and the external load on the robot.

In order to model the friction of the current-carrying pantograph-catenary system, the LuGre static friction model was established by experimental research the relationship between friction force and pressure fluctuation frequency, pressure fluctuation amplitude, contact current, and sliding speed. The static parameters in the model were identified by using the McQuad method and the general global optimization method. Based on the established LuGre static friction model, by introducing dynamic parameters, the LuGre dynamic friction model was established. The dynamic parameters in the model were identified by combining Genetic algorithm with Simulink simulation. The outputs of model verifying the dynamic model with more effective, which provides a reference for the frictional prediction and frictional wear properties of pantograph-catenary system. [ABSTRACT FROM AUTHOR]

One of the goals of the university is to achieve the maximum values ​​of the competencies of the graduated specialist, which ensures his success in work, increases the competitiveness of the university, and contributes to the influx of more trained applicants. Ultimately, this indicator characterizes the maximum performance of the university in terms of impact on the national economy. The task of optimal construction of the educational process is the task of optimal management of the resources of the university and the student (university resources: labor, time, financial, computing, territorial, informational, etc.; student resources: labor, financial, time, etc.) - the search for an option that provides maximum indicator that evaluates the result. As for the criteria of optimality, the authors believe that it is possible to accept as an assessment of the learning outcome of a graduate of his competence. Then the research task is formulated as achieving a maximum of competencies in conditions of limited available resources. A graduate's competencies are a consequence of the level of study of academic disciplines, which, in turn, depends on the resources invested. In this formulation of the problem, we do not touch upon the issue of individual abilities and focus on the maximum result for each student within the framework of his abilities. This approach is focused not on a specific student, but on the creation of preferable conditions of the educational process, passing through which, students will achieve the maximum mastery of the system of competencies. The formulation of the problem of optimal resource allocation allows several options: a static model (one time interval); a system of hierarchical models (consideration of competencies by levels of detail); taking into account the duration of the impact of resources (dividing resources into capital and one-time); dynamic model (covering the entire training period); optimization of the structure of the curriculum (optimization of the time resource); the relationship between the competencies of personnel and the performance of the enterprise. The article presents a system of mathematical models for optimizing the allocation of university resources when organizing the educational process. The relationship between the competencies of personnel and the performance of the enterprise has been analyzed. The issues of interaction between universities and the real sector of the economy through the formation of the competencies of a university graduate are considered.

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasing hydrocarbon recovery from tight reservoirs is an essential goal of oil industry in the recent years. Building real dynamic simulation models and selecting and designing suitable development strategies for such reservoirs need basically to construct accurate structural static model construction. The uncertainties in building 3-D reservoir models are a real challenge for such micro to nano pore scale structure. Based on data from 24 wells distributed throughout the Sadi tight formation. An application of building a 3-D static model for a tight limestone oil reservoir in Iraq is presented in this study. The most common uncertainties confronted while building the model were illustrated. Such as accurate estimations of cut-off permeability and porosity values. These values directly affect the calculation of net pay thickness for each layer in the reservoir and consequently affect the target of estimating reservoir initial oil in place (IOIP). Also, the main challenge to the static modeling of such reservoirs is dealing with tight reservoir characteristics which cause major reservoir heterogeneity and complexities that are problematic to the process of modeling reservoir simulation. Twenty seven porosity and permeability measurements from Sadi/Tanuma reservoir were used to validate log interpretation data for model construction. The results of the history matching process of the constructed dynamic model is also presented in this paper, including data related to oil production, reservoir pressure, and well flowing pressure due to available production. [ABSTRACT FROM AUTHOR]

In this paper, we propose a tandem tethered balloon scheme as a solution for increasing the operating altitudes of balloons to near-space altitudes of more than 20 km. By adding a middle balloon with a smaller volume than that of the top balloon in the middle weak wind zone, this scheme partially offsets the weight of the tether above the middle balloon, thereby greatly increasing the operating altitude of the tethered balloon. Another significant advantage of this scheme is that, when the working altitude exceeds 20 km, the opposite directions of the winds at high and low altitudes can be exploited to reduce the horizontal displacement of the top balloon, raising the safety factor and the wind-resistant capabilities of the tether. In this paper, a three-dimensional static model is established for the tandem ultra-high-altitude tethered balloon, and a static equilibrium governing equation of the tandem ultra-high-altitude tethered balloon is derived. In addition, a design method based on the principle of the tether safety factor has been proposed for the tandem tethered balloon. For the first time, a sensitivity analysis was conducted for the tether resistance coefficient, balloon resistance coefficient, and balloon lift coefficient for the design optimization and flight test stages. Finally, we analyzed the three-dimensional cross-sectional profile of the tether, the maximum tension of the tether, the length of the tether, and the variation of the angle between the ground end of the tether and the horizontal plane for a tandem tethered balloon system that remained airborne continuously for one month. This work confirms that the model is viable in complex and variable wind field environments and capable of long-duration flights. [ABSTRACT FROM AUTHOR]

Desire has been a marginal topic in TESOL. This study investigated whether and to what extent English learning affects Taiwanese young females’ aspiration toward western males. Four hundred ninety-nine respondents filled out a questionnaire that investigates their English learning experience and aspiration to cross–culture marriage with western males. Sixteen were interviewed. Results showed correlations between the acceptance of marrying a westerner and the following variables (in the rank of strength): 1. Preference for western movie stars, 2. Parents’ attitudes toward marrying a westerner, 3. Perceptions of compliments from native-English-speaking teachers, 4. Making foreign friends as the motivation to learn English, 5. The fondness of learning English, 6. Becoming more charming as the motivation to learn English, and 7. Going abroad as the motivation to learn English. The findings suggest that the experience and motivation of English learning did influence the female students’ aspiration toward western males, but not as strong as their inner motivation and the mass media.

Among various cultural models, the dichotomy of static versus dynamic models has provided a fertile ground for research. Although a number of static models are suggested, the dominant trend in almost all static models is provided by Hofstede who focuses on cultural differences along four major dimensions (power distance, individualism, uncertainty avoidance, and masculinity) and reduces “the complex phenomenon of culture in simple and measurable terms” (Fang, 2010, p. 156). The main concern is whether static bipolar models can cope with the requirements of the globalized era when cross-cultural communication “in an increasingly borderless and wireless workplace, marketplace, and cyberspace” (Fang, 2012, p. 2) is needed. Studying Fang’s dynamic cultural model versus Hofstede’s static cultural dimensions theory, the present paper, through the case study of Iranian culture, hypothesizes that dynamic models, such as Fang’s (2005, 2012), which recognize the paradoxical essence of cultures, emphasize all-dimensional cultural nearness. In Fang’s model, cultures are dialogic and open for cross-cultural interaction rather than monologic and segregated.

Three-dimensional simulation using geostatistical methods in terms of the possibility of creating multiple realizations of the reservoir, in which heterogeneities and range of variables changes are well represented, is one of the most efficient methods to describe the reservoir and to prepare a 3D model of it and the results have been used as acceptable results in the calculations due to the high accuracy and the lack of smoothing effect in small changes compared to the results of Kriging estimation. The initial volumetric tests of the Hendijan reservoir in southern Iran were carried out according to the construction model and the petrophysical model prepared by the software and according to the fluid contact levels, and the ratio of net thickness to total thickness in different reservoir zones. The calculations can be distinguished based on the zoning of the reservoir and also on the basis of type of facies. Accordingly, the average volume of fluid in place of the field is calculated in different horizons. The results of the simulation showed that the Ghar reservoir rock has gas and Sarvak Reservoir has the largest amount of oil in place.

Underactuated robotic grippers have the advantage of lower cost, simpler control, and higher safety over the fully actuated grippers. In this study, an underactuated robotic finger is presented. The design issues that should be considered for stable grasping are discussed in detail. This robotic finger is applied to design a two-fingered underactuated gripper. Firstly, a new three-DOF linkage-driven robotic finger that combines a five-bar mechanism and a double parallelogram is presented. This special architecture allows us to put all of the required actuators into the palm. By adding a torsion spring and a mechanical stopper at a passive joint, this underactuated finger mechanism can be used to perform parallel grasping, shape-adaptive grasping, and environmental contact-based grasp. Secondly, the dynamic model of this robotic finger is developed to investigate how to select an appropriate torsion spring. The dynamic simulation is performed with a multi-body dynamic simulator to verify our proposed approach. Moreover, static grasp models of both two-point and three-point contact grasps are investigated. Finally, different types of grasping modes are verified experimentally with a two-fingered underactuated robotic gripper.

There are still some errors and instabilities in futures analysis. In order to improve the accuracy of prediction, this study combines image processing technology and applies image processing technology to interest rate wireless to construct a static model based on image processing. The necessary conditions for no arbitrage are realized by adjusting the price of issuing virtual vouchers at a parity, that is, the discount rate is monotonous in discrete cases. In addition, this paper obtains static model statistical graphs through data, and combines image noise processing and image segmentation technology to improve the clarity of statistical graphs and records the results for analysis of this research model. The research shows that the model proposed in this study has certain feasibility in futures analysis and can provide theoretical reference for subsequent related research. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examines the effect of governance on the attractiveness of FDI through a sample of 41 African countries. We contribute to the literature by using various measures of institutional quality to identify the institutional quality aspects that affect the attractiveness of FDI in African countries. We use both the static panel data approach (fixed effect (FE) and random effect (RE)) and the dynamic panel approach (GMM in system). The empirical results show that the attractiveness of FDI to African countries is positively correlated with the control of corruption, the effectiveness of governments, the quality of regulation, and the voice and accountability. The results of this study imply that the dynamics of the modern economy requires African countries to improve the dimensions of governance and establish good governance practices. [ABSTRACT FROM AUTHOR]

This study presents a new solution to cope with the intermittent nature of renewable generations (RGs) and facilitate the integration of RGs in the smart active distribution network. Electric spring (ES) as one of the most influential solutions in demand‐side management is proposed as a flexible resource for flexible operation of grid‐connected microgrid against other sources of uncertainty such as forecasted load demand and energy price as well as the RGs output. This innovative approach has been considered in the context of a stochastic problem by presenting the static model of ES for the first time. The modelling of uncertainties is done by the roulette wheel mechanism as a scenario generation process and backward method for reducing the number of scenarios. In the proposed optimisation problem, the objective function is minimising the operating cost and voltage deviation as well as maximising system flexibility, subject to the AC power flow, ES and RGs constraints and technical system limitations. Finally, the proposed solution is tested on 33‐bus IEEE test system by the general algebraic modelling system software. The case studies demonstrate the efficiency of the proposed ES model in different simulation and experimental cases in providing flexi‐renewable microgrid. [ABSTRACT FROM AUTHOR]

This study investigated the spatial distribution of an oil field’s petrophysical parameters, including porosity and permeability, by determining and identifying the hydraulic flow units. By identifying hydraulic flow units as well as rock types and investigating the distribution of porosity and permeability variables, good quality and suitable areas of reservoir could be classified. Permeability relationships are noteworthy since they can be used to identify flow units for evaluation of reservoir quality. Therefore, in the present study, using results from six wells from the upper Surmeh formation in the subject oilfield, a 3D static model of a reservoir was developed. This was carried out after determining the Hydraulic Flow Units (HFU) by the probability diagram of the normal logarithm of Flow Zone Indicators (FZI) (based on the continuous variable of FZI). The Sequential Index Simulation (SIS) method was used for model development. As the result of this study and under the developed model, the probable distribution of these parameters for each cell in the reservoir were calculated, considering mean permeability and porosity. Different areas in the field with respect to reservoir quality were also determined, even for areas in which there was no sufficient core data. In summary, the HFU3 and HFU4 have the best reservoir quality, while the HFU1 and HFU5 have the lowest reservoir quality. This is of the most important issues for reservoir optimum production planning. The study provides deep understanding of how HFUs are spread. In addition, the results of this study can be used for the development of a dynamic model. [ABSTRACT FROM AUTHOR]

In this study, a mathematical model, which combines two of the most important airline revenue management strategies, namely overbooking and seat inventory control, is applied in Thailand's passenger airline data. Using this model, it is possible to find a closed-form solution for both the optimal booking limit and the optimal overbooking limit, simultaneously. Numerical study was set to evaluate the performance of the two-class overbooking model and to test three hypotheses using real-life data. Our two-class overbooking model outperformed the fixed-booking limit policy. Moreover, three hypotheses: the effect of varying the number of update booking limit points, the effect of an incorrect initial mean for demand, and the effect of a number of smoothing constants on an exponential smoothing method were tested using real-life data. At the 0.05 significance level, it was found that different numbers of update booking limit points affected profit, incorrect initial mean for demand did not affect profit when a high number of update booking limit points was set, and all of the smoothing constants in exponential smoothing method affected profit to some extent.

We propose a two-class revenue management (RM) model, which combines two of the most important RM strategies, namely overbooking and seat inventory control for a passenger airline. We derive a closed-form expression for an optimal overbooking limit that maximizes the expected profit, and analytically perform sensitivity analysis by changing model parameters such as a revenue, a penalty cost associated with unsatisfied demand, a show-up probability, a refund, a denied boarding cost, and a plane capacity.

Background: The combination of various continuum manipulators is a potential solution to break the bottleneck of continuum manipulators. However, continuum manipulators dissatisfy the constant curvature assumption due to the influence of joints., Methods: In this paper, a mechanics-based kinematic model of the compound continuum manipulator is proposed, which indicates that the curvature is non-constant. The static model of the manipulator is established, and the relationship of the bending angles is obtained. An efficient static-based Inverse Kinematic Algorithm using Polynomial Curve (IKAPC) of the manipulator is proposed. The polynomial curve is used to fit the end trajectory of the first manipulator., Results: The simulation results show that the IKAPC is 354 times faster than the Levenberg-Marquardt algorithm. The experimental results show that the mechanics-based model improves the position accuracy by 3.75 times over the constant curvature method., Conclusion: This paper is critical for solving the inverse kinematics of the compound continuum manipulator., (© 2023 John Wiley & Sons Ltd.)