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Ecological efficiency of production and the ecological footprint of organic agriculture
Matja？ Turinek B.Sc., Young researcher,Maja Turinek,Silva Grobelnik Mlakar M.Sc., Senior Lecturer,Franc Bavec Ph.D., Full Professor
Journal for Geography , 2010,
Abstract: The rising energy prices and climatic changes have intensified the search for alternative farming systems where energy consumption per unit would be lowered. A long-term field trial, started in 2007 at the University of Maribor, focuses on food quality and the ecological footprint of onventional (CON), integrated (INT), organic (ORG) and biodynamic (BD) farming systems. The gained data has been evaluated and interpreted using the SPIonExcel tool. Results from the first year show better environmental performance of both, ORG and BD systems in production of wheat (Triticum aestivum L.) and spelt (Triticum spelta L.), mainlydue to the non-use of external synthetic production factors. When yields are added to the equation, the ORG and BD systems emerge also as more efficient per unit of land area. Thus, the ORG and BD farming systems present viable alternatives for reducing the impact ofagriculture on climate change, while ensuring a more sustainable food security.
Experimental and numerical study on buckling of axially compressed composite cylinders
Edgars Eglītis, M.sc.ing., Reasearcher , Kaspars Kalni , Dr. sc.ing., Leading researcher , O gerts Ozoli , M.sc.ing., Researcher
Scientific Journal of Riga Technical University. Construction Science , 2009, DOI: 10.2478/v10137-009-0004-2
Abstract: Thin shells are lightweight, efficient structures that can support very high buckling loads. However, unlike columns and plates, shells usually have a very unstable post-buckling behaviour that strongly influences their buckling characteristics. Axially compressed cylinder may be one of the last classical problems in structural mechanics for which it remains difficult to obtain close agreement between careful experiments and the best predictions from numerical modelling, and therefore much more research is needed on this subject. Within this investigation, 18 glass fibre composite shells with wall thickness of 1.1 mm, 0.3 m and 0.5 m diameters and various lengths have been produced along with flat specimens for determination of elastic properties of the material. The cylinders were repeatedly loaded until post-buckling and load-shortening curves and pictures of buckling mode shapes have been registered. Finite element models of the specimens have been developed in ABAQUS finite element package and non-linear explicit dynamic analyses have been performed for comparison with experimental and analytical results. Gradually improving the finite element model and adding artificial initial imperfections resulted in good agreement between the experimental and numerically obtained critical loads. The buckling modes observed during the experiments are in good agreement with the results of finite element simulations as well.
Explanation of Residential Satisfaction in the internal and external renewal Experiences of Deteriorated urban areas
1Urbanization PhD Researcher, College of Fine Arts, University of Tehran, Tehran, Iran
- , 2015,
Abstract: Deteriorated urban textures are areas of a city isolated from developmental life cycle. They have turned into the focus of problems and inefficiencies. The evaluation of renewal actions claims to promote residents’ satisfaction in some cases. At the same time of improving objective and economic quality of life, there are claims regarding the lack of any improvements in their subjective quality of life. Above physical reforms, renewal actions in deteriorated textures should consider the issue of enhancing residents’ quality of life. Hence, besides considering physical aspects, renewal thoughts must also seek to provide and promote their quality of life and satisfaction. This article explains the status of residents’ satisfaction in the internal and external experiences of urban deteriorated fabrics renewal. To do so, first, the aspects of residential satisfaction in deteriorated textures will be discussed. Then, the status of these aspects in renewal experiences will be reviewed. Accordingly, the aspects of achieving residential satisfaction in these fabrics are explained via deductive reasoning method. Based on historical research method, renewal experiences are studied regarding the aspects of residential satisfaction. Residential satisfaction in deteriorated fabrics is influenced by all physical-environmental, services, socio-cultural, managerial, and economic aspects. Reviewing the renewal experiences across the world showed that, by 1990s, renewal was only continued based on physical and economic aspects in deteriorated areas. Yet, in this decade, it was tried to include social, managerial, and subjective aspects of residential satisfaction in the renewal of these textures by participating residents and stakeholders in the whole renewal process and using the existing social capital. In Iran, again, the evolutions of renewal thinking and actions show that, by 2000s, renewal was mainly done based on physical and economic aspects with a rationalistic, top-down and one-way management. Yet, in 2000s, it was tried to provide the scene for considering social and qualitative issues by participatory planning and development in the local scale.
A Web Clustered System for Achieving Higher Performances through Load Balancing Mechanism  [PDF]
Young Rhee
American Journal of Industrial and Business Management (AJIBM) , 2013, DOI: 10.4236/ajibm.2013.33041
Abstract:

In this paper, we study a methodology of distributing client requests in the LVS cluster system. The basic WLC algorithm is studied intensively. A load distributing algorithm which assigns its weight into each real server is devised by considering the state of the network resources on real servers. Network simulation is executed to estimate balanced usage of the resource using web load generating software. In order to analyze the dynamics of server performance due to the workload, we model a system software to evaluate the level of load balancing in the LVS, and perform actual experiments using web agenda. It is shown that the correction potentiality of the suggested algorithm is somewhat better than the WLC algorithm in terms of balanced resources usage.

A Study on the Balanced Assignment of Allocating Large Group with Multiple Attributes into Subgroups  [PDF]
Young Rhee
American Journal of Industrial and Business Management (AJIBM) , 2018, DOI: 10.4236/ajibm.2018.86095
Abstract: In this paper, a balanced assignment methodology is proposed in case of entity with more than 2 attributes. The Mahalanobis distance is a basic idea of MTS method as a distance indicator considering the correlation of entities in quality control techniques. This can be applied to ensure the balanced assignment, and utilized the Signal to Noise Ratio as a measure of classifying large groups with entities into many subgroups. In order to analyze the balanced assignment, the simulation is performed for a given example. Validations against simulation data establish the effectiveness of this approach.
Comparison and Validation of Distance on the Balanced Assignments of Group Having Entities with Multiple Attributes  [PDF]
Young Rhee
American Journal of Industrial and Business Management (AJIBM) , 2019, DOI: 10.4236/ajibm.2019.96096
Abstract:
In this paper, the balanced assignment is studied in classification of a group with multiple attribute into many subgroups without losing its similarity. The similarity or closeness in clustering is often measured as a distance. The Mahalanob distance is considered as one of the tools for measuring its closeness. The comparison between the distance criterion is shown by changing a specific assignment standard, and finally comparing it against the MTS method.
An Analysis and Validation of Effectiveness on Demand Forecasting Considering the Planned Order Effect*  [PDF]
Young Rhee
American Journal of Industrial and Business Management (AJIBM) , 2021, DOI: 10.4236/ajibm.2021.1110063
Abstract: The accuracy of forecasting is guaranteed for applying the time related forecasting method under normal circumstances. However, man-made situations, such as planned order can lead to completely different forecasting results. The research to enhance the accuracy of forecasting is meaningful in that it can be improved by controlling the details of planned order. In this study, an effect of planned order is introduced and the method to enhance the accuracy of demand forecasting in the planned order system is proposed. The validity of the system is examined by comparing the effectiveness of demand forecasting under the planned order system.
Verification of Clustering Accuracy by Applying Direction-Based Method and Data Conversion  [PDF]
Young Rhee
Modern Economy (ME) , 2021, DOI: 10.4236/me.2021.1211080
Abstract: In this study, the process of clustering into a group with similar characteristics is shown through pattern analysis, and the similarity is examined whether this group has homogeneity. A direction-based method for clustering the time series data is introduced, and the grouping process is carried out through the direction setting by up or down and the logical operations thereafter. The similarity is verified by comparing the parts within the group after clustering. For more effective verification, data conversion, a data homogenization process, is performed. MAD, MSE, MPSE and TS are reviewed as similarity indicators. For data such as time series data, MPSE and TS, which are scale-independent measurements, are recommended.
A General Hermitian Nonnegative-Definite Solution to the Matrix Equation AXB = C  [PDF]
Phil D. Young, Dean M. Young, Marsha M. Young
Advances in Linear Algebra & Matrix Theory (ALAMT) , 2017, DOI: 10.4236/alamt.2017.71002
Abstract: We derive necessary and sufficient conditions for the existence of a Hermitian nonnegative-definite solution to the matrix equation AXB = C. Moreover, we derive a representation of a general Hermitian nonnegative-definite solution. We then apply our solution to two examples, including a comparison of our solution to a proposed solution by Zhang in [1] using an example problem given from [1]. Our solution demonstrates that the proposed general solution from Zhang in [1] is incorrect. We also give a second example in which we derive the general covariance structure so that two matrix quadratic forms are independent.
A Comparison Study of Input ESD Protection Schemes Utilizing NMOS, Thyristor, and Diode Devices  [PDF]
Jin Young Choi
Communications and Network (CN) , 2010, DOI: 10.4236/cn.2010.21002
Abstract: For three fundamental input-protection schemes suitable for high-frequency CMOS ICs, which utilize protection devices such as NMOS transistors, thyristors, and diodes, we attempt an in-depth comparison on HBM ESD robustness in terms of lattice heating inside protection devices and peak voltages developed across gate oxides in input buffers, based on DC, mixed-mode transient, and AC analyses utilizing a 2-dimensional device simulator. For this purpose, we construct an equivalent circuit model of input HBM test environments for CMOS chips equipped with input ESD protection circuits, which allows mixed-mode transient simulations for various HBM test modes. By executing mixed-mode simulations including up to six active protection devices in a circuit, we attempt a detailed analysis on the problems, which can occur in real tests. In the procedure, we suggest to a recipe to ease the bipolar trigger in the protection devices and figure out that oxide failure in internal circuits is determined by the peak voltage developed in the later stage of discharge, which corresponds to the junction breakdown voltage of the NMOS structure residing in the protection devices. We explain strength and weakness of each protection scheme as an input ESD protection circuit for high-frequency ICs, and suggest valuable guidelines relating design of the protection devices and circuits.
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