جستجوی مقالات مرتبط با کلیدواژه « desirability » در نشریات گروه « کشاورزی »

Optimization of fertilizer and plant density are management approaches to improve resources efficiency and decline environmental pollutions. Response surface methodology (RSM) is defined as a set of mathematical and statistical techniques that are used to develop, to improve or to optimize a product by using Central composite designs. In this work, optimization of cow manure and plant density on biomass yield and essential oil percentage of peppermint as a medicinal plant species using central composite design for RSM was evaluated.

An experiment was conducted using central composite design with 13 treatments and two replications at the Research Field of Ferdowsi University of Mashhad during the growing season of 2017-2018. The treatments were allocated based on low and high levels of plant density (10 and 15 plants.m-2, respectively) and cow manure (0 and 70 t.ha-1, respectively). Fresh weight of stem, dried weight of stem, fresh weight of leaves, fresh weight of leaves, total dried weight and essential oil percentage in two sampling times and two cuttings were measured as dependent variables and changes of these variables were evaluated by a regression model. Lack-of-fit test was used to evaluate the quality of the fitted model. The adequacy of the model was tested by analysis of variance. The full quadratic polynomial equation was tested to determine the significance of the model and the component of the model (linear, squared and first-order interaction terms) and the quality of the fitted model was judged using the determination coefficient (R2).

The results showed that effect of linear and square components were significant on all studied characteristics in two sampling times. Interaction between the two factors of manure and plant density was significant on the studied traits only for the second sampling stage. Lack of fit had no significant effect on the studied traits. The full square model for the response variables gave insignificant lack-of-fit indicating that the data were satisfactorily explained. In the first and the second cuttings, R2 ranges for biomass yield and biomass yield+ essential oil were 70.39-84.62% and 27.36-63.06%, respectively. The highest observed and predicted values of biomass yield were recorded in 12.5 plants.m-2+ 35 t.ha-1 cow manure (755.13 g.m-2) and 15 plants.m-2+ 35 t.ha-1 cow manure (319.92 g.m-2), respectively. The mean yield of biomass yield in the second cutting was higher than the first cutting. Optimum levels of plant density and cow manure and desirability for biomass yield were calculated with 10 plants.m-2+23 t.ha-1 and d= 0.94 and the parameters for biomass yield, and essential oil percentage were with 10 plants.m-2, 49 t.ha-1 and d= 0.96, respectively.

In general, it seems that resource use optimization using RSM may be suitable cropping approach for sustainable production of medicinal plants in agroecosystems.

The effect of various levels (5, 10 and 15%) of fish protein concentrate (FPC) in batter formulation was investigated. The physicochemical properties of chicken nugget were evaluated in order to find the optimium level of FPC in batter formulation. Flow behavior showed that the control batter and a treatment contains of 7.5% FPC had higher viscosity. Moisture loss and fat uptake in control sample was higher than all treatments contain FPC in both deep fat and air fryer. Thicker crust resulted by higher level of FPC in batter leads less oil uptake during frying. Moreover, the samples contain FPC had the highest score in terms of texture and overall acceptability. In spite the fact that nuggets contain FPC had the high rate of our research priorities, however, the level around 15% considered as a limitation. Using desirability optimization, the range between 7.5- 8% of PFC in batter formulation was selected as the best level.

Entrepreneurship is a multi-faceted phenomenon, which, on the one hand, is affected by all economic, social, cultural and political dimensions and, on the other hand, affects these dimensions. Therefore, the development of entrepreneurship depends on the different aspects of the angles and the various aspects that necessitate the application of the ecosystem approach. This research was essentially aimed at examining the existing and desired status of the components of the ecosystem of entrepreneurship in knowledge companies. The statistical population of the research consisted of the members of knowledge societies in Kermanshah and Hamedan provinces. Using the Pontoon chart, 335 of them were selected through a sampling procedure. The main tool of the research was questionnaire, the reliability of the questionnaire was calculated by sequential alpha coefficient (88% -86% = α). The collected data were analyzed using SPSS software. The results showed that the greatest gap between the existing and the optimal level of the dimensions of the business ecosystem in the knowledge-based companies, in terms of support, financially, is visible and the smallest gap in the human resources, as well as the components related to the market and financial dimensions according to the amount z have the most difference

Groundwater is predominantly a renewable resource, and when managed properly can ensure a long-term water supply for increasing water demand and for climate change impacted region. Surface water renews as part of the hydrologic cycle in an average time period ranging from approximately 16 days (rivers) to 17 years (lakes and reservoirs); however, the average renewal time for groundwater is approximately 1400 years for aquifers to millions years for some deep fossil groundwater. Groundwater depletion, which is the reduction in the volume of groundwater storage, can lead to land subsidence, negative impacts on water supply, reduction in surface water flow and spring discharges, and loss of wetlands. Water balancing strategy has been considered as one of the most effective options to mitigate the groundwater depletion, and thus the balancing scenarios are applied as main approach to manage ground water sustainably. The purpose of the water balancing strategy in aquifers management is that groundwater level to be returned to the primary water level and to compensate the water resources shortage of aquifers’ storage.
1. Case study: Birjand aquifer with an area of 1100 square kilometers is situated in eastern part of Iran. The location of the aquifer is between 59o 45 and 58o 43 east longitude, and 33o 08 and 32o 34 north latitude.
2. Modeling: Laplace Equation is the basic equation for groundwater flow study in steady or unsteady states. In simulation by using numerical models, the boundary of the model, recharge and discharge resources, evaporation and recharge zones are important elements. After finding the key components of the conceptual model, the MODFLOW software was applied for simulation of groundwater. MODFLOW, which is a computer code that solves the groundwater flow equation and uses finite-difference method, is provided by the U.S. Geological Survey.
3. Sustainability Analysis: In order to achieve the objective of this study, water balancing scenarios should be evaluated for sustainability of the groundwater system using appropriate indices. Here, three indicators of reliability, vulnerability and desirability are proposed and were employed to assess the stability of groundwater system in different balancing scenarios in lumped and distributed forms. The aquifer sustainability index is expressed in Equation 4. In this equation, three indicators of aquifer reliability (Equation 1), aquifer vulnerability (Equation 2) and Desirability (Equation 3) have been used to assess the stability of groundwater system. The aquifer reliability index means in what extent the withdrawal scenario has been able to return the aquifer to its original state using the Equation 1 as follows:(1)
In which the number of periods where the groundwater level is above the desired level (equilibrium balance) and the total number of time steps in simulation. The vulnerability index indicates the amount of shortage in the groundwater storage and expresses the severity of the system failures using the Equation 2 as follows:(2)
In this equation, the desired groundwater level at time step t, the groundwater level simulated in t time period for each scenario, the groundwater level without scenarios and n the number of periods where the groundwater level is lower than the desired level. The index of the likelihood of returning the system to a favorable state is presented as an indicator of the desirability of the system using the Equation 3 as follows:.
(3)
In this equation, indicates the f ground water level after the depletion, is the desired level of groundwater and is the groundwater level (without the scenario). After estimating three indicators of reliability, vulnerability and desirability, the sustainability index for each scenario can be appraised using Equation 4.
(4)
In this equation, groundwater sustainability index, reliability index, desirability index and vulnerability index.
In this study, six water balancing strategies were employed to reduce 1, 1.5, 2, 2.5, 3 and 3.5 percent water withdrawing for agricultural water use. Results of the simulation of different water balancing strategies demonstrated that with reducing in water use, the stability index has been improved significantly. The improvement changes from 32% increase in the index for 1% water withdrawing reduction scenario to 88% increase in the index for the 3.5% water withdrawing reduction scenario. Moreover, the reviewing of the stability indices of the system in various scenarios reveals that a 2.5% reduction in water use will assistance the aquifer status achieve to a stable state.
In order to manage groundwater withdrawal, it is easier to assess the impact of the water balancing scenarios using the groundwater sustainability index. The review of sustainability indices in the studied aquifer shows that by reducing 1% of the water harvest, 32% of the system's stability increases, and if water harvest reduction reaches 3.5%, the index increases 88%. Considering the distributed potential and possibility of the investigation of different scenarios by proposed indices in this study, they can be applied to assess and manage other similar aquifers.

One of the strategies, is conducting artificial recharge, which is required to be evaluated using sustainability indexes in order to quantify the effects. In this research, a new approach is utilized for evaluation of groundwater system sustainability, combining the indexes, reliability, vulnerability and desirability considering the effect of artificial recharge scenario. First, the effect of Shurab Sivjan artificial recharge project on Birjand aquifer is simulated for a nine-year period, projected to 1404 Hijri (2025 Gregorian) with normal climatic condition, using MODFLOW model. Simulation results show that aquifer system sustainability is higher in the downstream parts, where the Khusf observation well is located, justifying by the groundwater recharge flow direction, low difference between optimum and measured groundwater level, and thin saturated thickness with 55 percent. Evaluation of indexes over the aquifer shows that the artificial recharge project could enhance the system sustainability between 21 to 25 percent according to reduce, constant and increment discharge scenarios. The proposed index in this research can be utilized for the other aquifers as well as in decision-making, because of its ability to define in distributed manner and possibility of evaluating the effects of different scenarios.