• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.402-407
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• 2010

Zerovalent iron (ZVI) is one of the most commonly used metallic reducing agents for the treatment of toxic contaminants in wastewater. Traditional ZVIs are less effective than nanoscale ZVI (nZVI) due to prolonged reaction time. However, the reactivity can be significantly increased by reducing the size of ZVI particles to nanoscale. In this study, nZVI particles were synthesized under laboratory condition and their efficiency in removing hexavalent chromium (Cr(VI)) from aqueous solutions were compared with commercially available ZVI particles. The results showed that the synthesized nZVI particles (SnZVI) reduced >99% of Cr(VI) at the application rate of 0.2% (w/v), while commercial nZVI (CnZVI) particles resulted in 59.6% removal of Cr(VI) at the same application rate. Scanning electron micrographs (SEM) and energy dispersive spectra (EDS) of the nZVI particles revealed the formation of Fe-Cr hydroxide complex after reaction. Overall, the SnZVI particles can be used in treating chromium contaminated wastewater.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.8
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• pp.71-80
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• 2022

This study aims to investigate the effects of fair value valuation of biological assets and bearer plants measured at historical cost on the cost of third-party capital. The study contributes to the agricultural sector and the International Accounting Standard - IAS 41, which has been modified to remove the requirement to apply fair value for bearer plants, one of the primary biological assets with no active market. For this, 182 companies from 39 countries were studied in the years 2020 and 2021, with information taken from the Thomson Reuters Eikon platform. The methodology involves regression by the ordinary least squares method based on the model of Daly and Skaife (2016). The results show that the biological asset at fair value does not influence the cost of debt and that the measurement of bearer plants at historical cost has no effect on the cost of debt. Fair value did not change the perceived cost of debt of the analyzed companies in the studied period, contrary to Daly and Skaife (2016). Finally, the cost of third-party capital can be influenced by other aspects related to profit quality, which were not examined in this paper, such as profit management.

• Korean Journal of Biological Psychiatry
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• v.6 no.1
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• pp.30-33
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• 1999

While depression is certainly a prevalent disorder, it is often severe and debilitating and does not always have the good prognosis we have been led to expect. Social approaches to affective disorders have not been subjected to the same level of scrutiny as the interventions used in the management of schizophrenia. Psychosocial Rehabilitation is now at a critical stage. Psychoeducation, social skill training, cognitive remediation, family education, vocational rehabilitation and case management programs are essential for the rehabilitation of chronic depression.

• Journal of Species Research
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• v.1 no.2
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• pp.249-256
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• 2012

Located 60 km from southern tip of Korean peninsula, Jeju is the largest Island in Korea and composed of volcanic habitat. Twenty-eight species of terrestrial mammals are listed from Jeju Island, of which 1 species and 3 subspecies are endemic. Also, 1 endangered species and 4 invasive alien species of land mammals are listed. Current status, brief history, management and conservation of the 28 species are discussed.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.49-61
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• 2021

Integrated mite management provided a basic direction to early the fruit tree IPM. The early IPM concept was based on incorporation of the biological control for mite pests with the existing chemical control compatibly. Since then, the hypotheses and mechanisms of the interaction between species diversity and pest population dynamics have provided a broader understanding of mite-centered pest management in fruit tree ecosystems. Based on the principle of the ecosystem, biological control and pest management through habitat modification or manipulation are developing to the concept of agro-ecological engineering. In particular, the natural enemy diversity is dynamically changed according to the different cultivation environment in the management of mite pests, and the species composition of phytophagous mites is also changed by the environment for orchard management. This paper reviews the biological control of mites, which was the basis of apple IPM, and also re-examines the topics of species diversity and pest management, predacious mite diversity in relation to mite control and the change of species composition of mite pests in the sight of ecological engineering. Finally, we suggest a strategy for biological control of spider mites in apple orchards in Korea.

• Journal of Korea Technology Innovation Society
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• v.11 no.2
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• pp.219-240
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• 2008

This paper aims to suggest a policy for biological resource based on a comprehensive understanding on biological resources. Biological resources are different from traditionally recognized viable organisms (Biodiversity) in ecosystems. Biological resources are culturable and replicable resources of living organisms such as tissues, cells and genes. Moreover, biological resources include human-derived biological materials. Biological resources is not simply a matter of science and technology. Biological resources should be dealt with as national resources. There are many international issues regarding biological resources, such as intellectual property rights (IPRs), safety on handling and distribution, material transfer agreements (MTAs) for mutual benefits and biological standards. Ethical debates are also being raised because biological resources are related with human-derived biological materials. Every nation has tendency to adopt its government policies to strengthen its sovereignty on biological resources and international cooperation. In addition, international linkages are essential for providing enhanced worldwide accessibility to biological resources. Japan has shown several international initiatives in the field of biological resources. Korea has just begun to design appropriate policies for the use and R&D of biological resources. Therefore, this paper suggests the following needs: 1) policy at the national level beyond the interests of researchers, 2) inter-ministerial coordination across government ministries, 3) expansion of scope and size of each BRC (Biological Resource Centers), and 4) building networks and systems such as national information center, representative centers by field, and each BRC.

• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.64-79
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• 2017

Identifying disease genes from human genome is a critical task in biomedical research. Important biological features to distinguish the disease genes from the non-disease genes have been mainly selected based on traditional feature selection approaches. However, the traditional feature selection approaches unnecessarily consider many unimportant biological features. As a result, although some of the existing classification techniques have been applied to disease gene identification, the prediction performance was not satisfactory. A small set of the most important biological features can enhance the accuracy of disease gene identification, as well as provide potentially useful knowledge for biologists or clinicians, who can further investigate the selected biological features as well as the potential disease genes. In this paper, we propose a new stepwise random forests (SRF) approach for biological feature selection and disease gene identification. The SRF approach consists of two stages. In the first stage, only important biological features are iteratively selected in a forward selection manner based on one-dimensional random forest regression, where the updated residual vector is considered as the current response vector. We can then determine a small set of important biological features. In the second stage, random forests classification with regard to the selected biological features is applied to identify disease genes. Our extensive experiments show that the proposed SRF approach outperforms the existing feature selection and classification techniques in terms of biological feature selection and disease gene identification.

• Journal of Forest and Environmental Science
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• v.36 no.4
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• pp.298-310
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• 2020

Fuel management can play enormous role in fire management in tropical dry forests. However, unlike the temperate forests, knowledge on implications of different fuel management methods in tropical forests is often inadequate. In this study, the implications of prescribed burning and hand thinning treatments on implementation cost, fuel loading and post-treatment fire behaviour were tested and compared in degraded forests and teak plantations in two forest reserves of different levels of dryness in Ghana. The study found that prescribed burning was less expensive (62.02 US Dollars ha-1) than hand thinning (95.37 US Dollars ha-1). The study also indicated that the two fuel management methods were able to reduce fuel loading in degraded forests and teak plantations. However, prescribed burning was more effective in reducing fuel loading than hand thinning. While the relative change of fuel reduction was 13% higher in prescribed burning than the hand thinning in degraded forest, it was 41% higher in prescribed burning than hand thinning in teak plantations. The fire behaviour of post-treatment experimental fire was also lower in prescribed burning than the hand thinning and control plots. Fuel management, therefore, has a great potential in fire management in degraded forests and teak plantations in Ghana.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.790-793
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• 2020

Length-weight relationships (LWR) for 27 fish species inhabit Southern sea in Korea were investigated to describe several biological characters. Total 7,399 individuals were collected by R/V Tamgu-20 using bottom trawl between 2018 to 2019 and were identified as 19 families and 27 species. Parameter b ranged from 2.414 to 3.472. Thirteen species among 27 species showed isometric growth (b=3), six species showed negative allometry (b<3) and eight species showed positive allometry (b>3). The results of this study provide useful basic biological information about 27 fishes and are highly reliable due to use of data measured directly.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.932-937
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• 2011

Main objectives of this paper were; firstly, to explain impacts of suspended solid in the water body on the relationship between water quantity and water quality; secondly, study on the inter-relationship between organic materials, nutrients, pathogens, and suspended solids considering eco-friendly water resources. Relationship between water quality and water quantity is not easy to understand as it includes physicochemical-biological reactions and diffuse pollutions. Especially, suspended solid makes water resource management difficult. Eroded soil in the upper land transported to the downstream by water flows carrying biological and physicochemical information and sedimented in the downstream. As sediment scoured under high flow condition and environmental change, suspended solid and sediment should be emphasized for understanding the inter-relationship between water quality and water quantity. Knowledge gaps between known monitored data and management of suspended solid were identified as well for future study.