scholarly journals Erosion Transportation Processes as Influenced by Gully Land Consolidation Projects in Highly Managed Small Watersheds in the Loess Hilly–Gully Region, China

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1540
Author(s):  
Qianqian Ji ◽  
Zhe Gao ◽  
Xingyao Li ◽  
Jian’en Gao ◽  
Gen’guang Zhang ◽  
...  

The Loess Hilly–Gully region (LHGR) is the most serious soil erosion area in the world. For the small watershed with high management in this area, the scientific problem that has been paid attention to in recent years is the impact of the land consolidation project on the erosion environment in the gully region. In this study, the 3D simulation method of vegetation, eroded sediment and pollutant transport was innovated based on the principles of erosion sediment dynamics and similarity theory, and the impacts of GLCP were analyzed on the erosion environment at different scales. The verification results show that the design method and the scale conversion relationship (geometric scale: λl = 100) were reasonable and could simulate the transport process on the complex underlying surface of a small watershed. Compared with untreated watersheds, a significant change was the current flood peak lagging behind the sediment peak. There were two important critical values of GLCP impact on the erosion environment. The erosion transport in HMSW had no change when the proportion was less than 0.85%, and increased obviously when it was greater than 3.3%. The above results have important theoretical and practical significance for watershed simulation and land-use management in HMSW.

2021 ◽  
Vol 1 (1) ◽  
pp. 43-49
Author(s):  
Ernasari Ernasari ◽  
Cahyono Kaelan ◽  
Andi Armyn Nurdin

Balut bidai training aims to minimize the impact that can occur so that every lay person can help if they find victims who have an accident.The research aimed to analyze to what extent the effect of the splint wrap training using the watching video method on the fracture management knowledge of the Youth Red Cross members. This was the qualitative research with the one group pretest posttest design method with the samples of 70 students of YRC members. The samples were selected using the non-probability sampling technique with the purposive sampling approach. The date were analyzed using T-Test. The research result indicates that there is no significant difference concerning the knowledge level between the simulation group and video group (? = 0.063), whereas on the skill level, there is the significant difference between the simulation group and video group (? = 0.000). Thus, it can be concluded that the training using the video method can improve the fracture management knowledge fester than the training using the simulation method, so that it is expected that the training using the video method can be utilized for almost all topics, and every cognitive, affective, psychomotoric and interpersonal domain.


2020 ◽  
Vol 22 (9) ◽  
pp. 28-34
Author(s):  
Huseynova А.А. ◽  
Vashchinnikova K.D.

Turning to the new educational paradigm, the research paper considers the conditions for ensuring the effective-ness of authentic assessment of students ' achievements within the competence approach and the transition from traditional knowledge control to tests developed on the basis of the theory of pedagogical measurements. Special attention is paid to independent assessment as a tool for stimulating learning activities, as well as to the justifica-tion of the pattern design method used in the develop-ment of measurement tools. The experimental basis of the study is based on the results of an independent assess-ment of educational achievements of students of the sen-ior level of secondary vocational education in social studies in several educational organizations. As a result of the survey of participants in independent testing, the formation of a stable positive learning motivation is not-ed. The relationship with the assessment of the impact on educational motivation is confirmed by the respondents ' attitude to the authentic assessment procedure on the part of participants in the assessment process: school-children, teachers, and parents. As a result, it was re-vealed that all subjects of the educational process evalu-ate the impact of the proposed method of assessment on educational motivation from a positive side.


2012 ◽  
Vol 43 (1-2) ◽  
pp. 54-63 ◽  
Author(s):  
Baohong Lu ◽  
Huanghe Gu ◽  
Ziyin Xie ◽  
Jiufu Liu ◽  
Lejun Ma ◽  
...  

Stochastic simulation is widely applied for estimating the design flood of various hydrosystems. The design flood at a reservoir site should consider the impact of upstream reservoirs, along with any development of hydropower. This paper investigates and applies a stochastic simulation approach for determining the design flood of a complex cascade of reservoirs in the Longtan watershed, southern China. The magnitude of the design flood when the impact of the upstream reservoirs is considered is less than that without considering them. In particular, the stochastic simulation model takes into account both systematic and historical flood records. As the reliability of the frequency analysis increases with more representative samples, it is desirable to incorporate historical flood records, if available, into the stochastic simulation model. This study shows that the design values from the stochastic simulation method with historical flood records are higher than those without historical flood records. The paper demonstrates the advantages of adopting a stochastic flow simulation approach to address design-flood-related issues for a complex cascade reservoir system.


2021 ◽  
Vol 19 (1) ◽  
pp. 63-73
Author(s):  
Aimable Nsabimana ◽  
Fidele Niyitanga ◽  
Dave D. Weatherspoon ◽  
Anwar Naseem

Abstract Rwanda’s “Crop Intensification Program (CIP)” is primarily a land consolidation program aimed at improving agricultural productivity and food security. The program, which began in 2007, focuses on monocropping and commercialization of six priority crops: maize, wheat, rice, white potato, beans, and cassava. CIP has facilitated easy access to improved seed stocks, fertilizer, extension services, and postharvest handling and storage services. Although studies have documented the impact of CIP on changes in farm yield, incomes, and productivity, less is known about its impact on food prices. In this study, we examine the crop-food price differences in intensive monocropped CIP and non-intensive monocropped CIP zones in Rwanda. Specifically, the study evaluates price variations of beans and maize along with complementary food crops in intensive and non-intensive monocropped zones before and after the introduction of the CIP policy. We find that the CIP policy is not associated with differences in CIP crop prices between the intensive and non-intensive monocropped zones. Over time, prices increased for CIP crops but generally, the crop prices in the two zones were cointegrated. Prices for non-CIP crops in the two different zones did show price differentials prior to the implementation of CIP, with the prices in intensive monocropped zones being greater than in the non-intensive monocropped zones. Moreover, the prices in intensive areas are cointegrated with prices in non-intensive areas for maize and beans and these prices are converging. This indicates that farmers who intensively produced one CIP crop were able to go to the market and purchase other food crops and that price differences between zones have decreased over time, potentially making the CIP intensive farmers better off.


Author(s):  
Min-Guk Seo ◽  
Chang-Hun Lee ◽  
Tae-Hun Kim

A new design method for trajectory shaping guidance laws with the impact angle constraint is proposed in this study. The basic idea is that the multiplier introduced to combine the equations for the terminal constraints is used to shape a flight trajectory as desired. To this end, the general form of impact angle control guidance (IACG) is first derived as a function of an arbitrary constraint-combining multiplier using the optimal control. We reveal that the constraint-combining multiplier satisfying the kinematics can be expressed as a function of state variables. From this result, the constraint-combining multiplier to achieve a desired trajectory can be obtained. Accordingly, when the desired trajectory is designed to satisfy the terminal constraints, the proposed method directly can provide a closed form of IACG laws that can achieve the desired trajectory. The potential significance of the proposed result is that various trajectory shaping IACG laws that can cope with various guidance goals can be readily determined compared to existing approaches. In this study, several examples are shown to validate the proposed method. The results also indicate that previous IACG laws belong to the subset of the proposed result. Finally, the characteristics of the proposed guidance laws are analyzed through numerical simulations.


2020 ◽  
Vol 12 (24) ◽  
pp. 10454
Author(s):  
Katarína Teplická ◽  
Martin Straka

This article summarizes the arguments within the scientific discussion on the issue of using mining machines and their life cycle. The main goal of the article is to investigate the impact of a combination of mobile and stationary mining machines and their optimal distribution in the mining process to increase the efficiency of mining and processing of raw materials. The following methods of research were focused on the use of technical indicators for the valuation efficiency of the mining process: a simulation method was used for the distribution of mining machines, comparison analysis was used for the real and past state of mining machines, and a decision tree was used as managerial instrument for optimal alternatives of mining machines. The research empirically confirms and theoretically proves that optimal distribution of mining machines and machine parks is very important for mining companies. The benefit of this research for the mining company was the new location of the machines and the combination of stationary production lines and mobile equipment. The optimal layout of the machines reduced the number of conveyor belts and improved the transfer of limestone processing to mobile devices, saving time, which was reflected in transport costs. The results can be useful for other mining companies seeking to create an optimal machine park.


2020 ◽  
Vol 12 (4) ◽  
pp. 1578 ◽  
Author(s):  
Hongxia Sun ◽  
Yao Wan ◽  
Huirong Lv

Exhaust pollution and energy crises are worsening worldwide. China has become the largest motor vehicle producer; thus, promoting the use of new energy vehicles (NEVs) in China has important practical significance. In this paper, considering the limited rationality of governments, NEV enterprises and consumers, we study the subsidy policy of the China NEV market using the evolutionary game and system dynamics (SD) methods. First, a tripartite evolutionary game model is developed and the replicator dynamics equations and Jacobian matrix are obtained. A SD simulation of the model was conducted to further clarify the impact of the initial market proportion and three variables used in the model. The results show that the initial market proportion affects the evolution speed but does not affect the evolution result when the three group players all choose a mixed strategy. For governments, they should not hastily cancel price subsidies provided to consumers; rather, they should dynamically adjust the rate of the subsidy decrease and increase the consumers’ extra cost for purchasing fuel vehicles (FVs). NEV enterprises should appropriately increase their investments in the research and development (R&D) of NEVs.


Curationis ◽  
2019 ◽  
Vol 42 (1) ◽  
Author(s):  
Mosehle S. Matlala ◽  
Thanyani G. Lumadi

Background: Midwifery is the backbone of women and child healthcare. The shortage of staff in maternity units is a crisis faced by many countries worldwide, including South Africa.Objectives: This study aims to explore the perceptions of midwives on the shortage and retention of staff at a public institution.Method: The study was conducted at one of the tertiary hospitals in Tshwane District, Gauteng Province. A total of 11 midwives were interviewed through face-to-face and focus group interviews. An explorative, descriptive generic qualitative design method was followed, and a non-probability, purposive sampling technique was used. Thematic coding analysis was followed for analysing data.Results: The impact of shortage of midwives was reported to be directly related to poor provision of quality care as a result of increased workload, leading to low morale and burnout. The compromised autonomy of midwives in the high obstetrics dependency units devalues the status of midwives.Conclusion: Midwives are passionate about their job, despite the hurdles related to their day-to-day work environment. They are demoralised by chronic shortage of staff and feel overworked. Staff involvement in decision-making processes is a motivational factor for midwives to stay in the profession. The midwives need to be in the centre of the decision-making processes related to their profession. The revision of the scope of practice and classification of midwifery profession away from general nursing complex by the South African Nursing Council (SANC) could place midwifery in its rightful status.


2014 ◽  
Vol 1008-1009 ◽  
pp. 850-860 ◽  
Author(s):  
Zhou Wei Zhang ◽  
Jia Xing Xue ◽  
Ya Hong Wang

A calculation method for counter-current type coil-wound heat exchanger is presented for heat exchange process. The numerical simulation method is applied to determine the basic physical parameters of wound bundles. By controlling the inlet fluid velocity varying in coil-wound heat exchanger to program and calculate the iterative process. The calculation data is analyzed by comparison of numerical result and the unit three dimensional pipe bundle model was built. Studies show that the introduction of numerical simulation can simplify the pipe winding process and accelerate the calculation and design of overall configuration in coil-wound heat exchanger. This method can be applied to the physical modeling and heat transfer calculation of pipe bundles in coil wound heat exchanger, program to calculate the complex heat transfer changing with velocity and other parameters, and optimize the overall design and calculation of spiral bundles.


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