• Journal of Climate Change Research
• /
• v.6 no.2
• /
• pp.121-131
• /
• 2015

As the temperature has changed by climate change, changes in its own characteristic values of the chemical substance or the movement and distribution of chemicals take place in accordance with the changes of hydrological and meteorological phenomena. Depending on the impact of climate change on the chemical behavior, it is necessary to understand and predict quantitative changes in the dynamics of the environment of pollutants due to climate change in order to predict in advance the occurrence of environmental disasters, and minimize the impact on the life and the environment after the incident. In this study, we have analysed and compared chemical fate models validated by previous studies in terms of model configuration, application size and input/output factors. The potential models applicable to municipal and industrial areas were selected on the basis of characteristic of each model, availability of input parameters and consideration for climate change, identified the problems, and then presented an approach to improve applicability.

• Membrane and Water Treatment
• /
• v.10 no.4
• /
• pp.313-320
• /
• 2019

Increasing the concentration of nitrate ions in the soil solution and then leaching it to underground aquifers increases the concentration of nitrate in the water, and can cause many health and ecological problems. This study was conducted to evaluate the vulnerability of Meymeh aquifer to nitrate pollution. In this research, sampling of 10 wells was performed according to standard sampling principles and analyzed in the laboratory by spectrophotometric method, then; the nitrate concentration zonation map was drawn by using intermediate models. In the drastic model, the effective parameters for assessing the vulnerability of groundwater aquifers, including the depth of ground water, pure feeding, aquifer environment, soil type, topography slope, non-saturated area and hydraulic conductivity. Which were prepared in the form of seven layers in the ARC GIS software, and by weighting and ranking and integrating these seven layers, the final map of groundwater vulnerability to contamination was prepared. Drastic index estimated for the region between 75-128. For verification of the model, nitrate concentration data in groundwater of the region were used, which showed a relative correlation between the concentration of nitrate and the prepared version of the model. A combination of two vulnerability map and nitrate concentration zonation was provided a qualitative aquifer classification map. According to this map, most of the study areas are within safe and low risk, and only a small portion of the Meymeh Aquifer, which has a nitrate concentration of more than 50 mg / L in groundwater, is classified in a hazardous area.

• Natural Product Sciences
• /
• v.25 no.3
• /
• pp.222-227
• /
• 2019

Quantitative nuclear magnetic resonance (qNMR) is a well-established method adopted by international pharmacopoeia for quantitative and purity analyses. Emodin is a type of anthraquinone, well known as the main active component of Fabaceae, Polygonaceae and Rhamnaceae. Purity analysis of emodin is usually performed by using the high-performance liquid chromatography (HPLC)-UV method. However, it cannot detect impurities such as salts, volatile matter, and trace elements. Using the qNMR method, it is possible to determine the compound content as well as the nature of the impurities. Several experimental parameters were optimized for the quantification, such as relaxation delay, spectral width, number of scans, temperature, pulse width, and acquisition time. The method was validated, and the results of the qNMR method were compared with those obtained by the HPLC and mass balance analysis methods. The qNMR method is specific, rapid, simple, and therefore, a valuable and reliable method for the purity analysis of emodin.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.52 no.1
• /
• pp.59-66
• /
• 2019

The growth and maturation pattern of a commercial and endemic red algae Meristotheca papulosa were investigated in Jeju Island. Ecological researches were performed in a natural population of 10 m water depth in Sinheung from march 2014 to November 2015. Maximal blade length and weight of M. papulosa were 8.7 cm and 5.49 g in July 2014 and 10.7 cm and 10.17 g in September 2015, respectively. Growth in blade area of the species reached a maximum of $43.84cm^2$ and $67.41cm^2$ in July 2014 and 2015, respectively. Thalli in the field population were rarely observed from October to December but new recruits were found from January, following year. Carposporophytes were observed from June to September when bottom seawater temperatures were around $20^{\circ}C$. At the study site, seawater temperature was in the range of $14.9-25.7^{\circ}C$. Growth parameters of M. papulosa and relative abundance of carposporophytes showed significant correlation with environmental factors (temperature, salinity, DIN). In this result, we clarified the growth and maturation period of M. palpulosa, and provided effective data on the protection and management of natural populations and basic data for mass culture of the alga.

• Structural Engineering and Mechanics
• /
• v.69 no.5
• /
• pp.557-566
• /
• 2019

The reservoir basin bedrock produced significant impact on the long-term service safety of super-high arch dams. It was important for accurately identifying geomechanical parameters and its evolution process of reservoir basin bedrock. The deformation modulus mechanism research methods of reservoir basin bedrock deformation modulus for super-high arch dams was carried out by finite element numerical calculation of the reservoir basin bedrock deformation and in-situ monitoring data analysis. The deformation modulus inversion principle of reservoir basin bedrock in a wide range was studied. The convergence criteria for determining the calculation range of reservoir basin of super-high arch dams was put forward. The implementation method was proposed for different layers and zones of reservoir basin bedrock. A practical engineering of a super-high arch dam was taken as the example.

• Korean Journal of Agricultural Science
• /
• v.47 no.4
• /
• pp.727-742
• /
• 2020

Point cloud-based 3D maps can obtain many kinds of information for maintenance work on forest road networks. This study was conducted to compare the importance of each factor to select the factors required for the mapping of 3D forest road maps. This can be used as basic data for attribute information required to maintain forest road networks. The results of this study found that out of a total of 30 indexes extracted for mapping 3D forest roads, a total of 21 indexes related to stakeholder groups were significantly different. The importance of the index required by the civil service group was significantly higher than that of the other groups overall. In the case of the academic group, the index importance for cut slope, fill slope, and drainage facility was significantly higher. On the other hand, the index importance for the forestry cooperative and forest professional engineer group was mostly distributed between the civil servants' group and the academic group. In particular, the type of drainage system showed the highest value among the detailed indexes. Overall, drainage related factors in this survey had high coefficient values. The impact of water on forest roads was the most important part in road maintenance. In addition, the soil texture had a high value in relation to slope stability. This is thought to be because the texture of the soil affects the stability of the slope.

• Nuclear Engineering and Technology
• /
• v.54 no.9
• /
• pp.3299-3309
• /
• 2022

Nuclear energy has the potential to play an influential role in energy transition efforts than is now anticipated by many countries. Realizing sustainable human development and reducing global climate crises will become more difficult without significantly increasing nuclear power. This paper aims to probe the role of nuclear energy, external debt, and financial globalization in sustaining human development and environmental conditions simultaneously in BRICS (Brazil, Russia, India, China, and South Africa) countries. This study applied a battery of second-generation estimation approaches over the period from 1990 to 2019. These methods are useful and robust to cross-countries dependencies, slope heterogeneity, parameters endogeneity, and serial correlation that are ignored in conventional approaches to generate more comprehensive and reliable estimates. The empirical findings indicate that nuclear energy and financial globalization contribute to human development, whereas external debt inhibits it. Similarly, financial globalization accelerates ecological deterioration, but nuclear energy and external debt promote environmental sustainability. Moreover, the study reveals bidirectional feedback causalities between human development, carbon emissions and nuclear energy consumption. The study offers useful policy guidance on accomplishing sustainable and inclusive development in BRICS countries.

• Advances in materials Research
• /
• v.12 no.4
• /
• pp.287-308
• /
• 2023

The main objective of this article is to highlight the progress made in the development of new materials that have been gradually used by humans until today. Of course, this progress must be associated with other parameters in order to guarantee sustainable development. For this, today, it has become urgent to reduce the consumption of cement by resorting to its partial or total replacement by other similar materials in order to reduce CO₂ emissions in our environment. This should certainly help to develop greener building materials. In this study, it was decided to proceed with the partial or total replacement of Portland cement type CEM II/B-L-42.5N by slate and lime that had not undergone any previous transformation. The results obtained revealed that the mortar whose substitution compared to the replacement of cement (100%) cement and sand (0/4) confers better kinetics than those of the series composed of(100%) cement and fraction rubble (0/1).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.57 no.4
• /
• pp.372-379
• /
• 2024

The small yellow croaker Larimichthys polyactis is an important ecological and commercial species in the waters of Korea. Based on samples purchased monthly from a market from 2019 to 2021, except during the closed season, we analyzed the age and growth of the small yellow croaker using 894 otoliths. The total lengths of the small yellow croaker ranged from 12.0 to 38.9 cm, which is a sufficient length range for analyzing age structure and growth parameters. The translucent zone, formed during the spawning season in June, was counted as the annual mark. The estimated ages were 0-10 years, and the 38.9 cm individuals were 7 years old, while the 34.2 cm individuals were 10 years old. The highest proportion in this study (86.8%) was 0-3 years. The von Bertalanffy growth model was obtained as L_t=41.2(1-exp-^0.20(t+1.50)).

• Geomechanics and Engineering
• /
• v.39 no.2
• /
• pp.171-179
• /
• 2024

Gravity wall combined with anchoring frame beam is widely adopted to support a high slope under complex geomorphic condition, in which the rigid gravity wall is adopted as a lower structure and the flexible anchoring frame beam serves as an upper structure. The seismic anchor force and the seismic active earth pressure are two essential issues for the seismic design of combined retaining structure in high seismic intensity area. In this study, an analytical model of combined retaining structure is established based on the upper bound theorem of limit analysis, and the formulas for seismic anchor force and seismic active earth pressure of combined retaining structure are derived. The results are optimized by using the global optimization algorithm. The proposed method is verified by a comparison with previous method. Moreover, the influence of main parameters on seismic anchor force and seismic active earth pressure is analyzed to facilitate the seismic design of such combined retaining structure.