• Title/Summary/Keyword: Environmental conservation

Search Result 2,438, Processing Time 0.027 seconds

Environmental factors affecting roost use of shorebirds in the southern Kanghwa Island, Republic of Korea (강화도 남단에 도래하는 도요새들의 해안 내륙 휴식지 이용과 이들의 이용에 영향을 미치는 환경요인들)

  • Kim, Kwan Mok;Moon, Young Min;Yoo, Jeong Chil
    • Journal of Wetlands Research
    • /
    • v.15 no.2
    • /
    • pp.251-264
    • /
    • 2013
  • There are some factors affecting the shorebirds in selecting a coastal inland roost site where they have to stay during the high tide when the entire intertidal zone is covered with water. We investigated eight species (Eastern Curlews Numenius madagascariensis, Green Shanks Tringa nebularia, Bar-tailed Godwits Limosa lapponica, Grey Plovers Pluvialis squatarola, Dunlins Calidris alpine, Whimbrels Numenius phaeopus, Eurasian Curlews Numenius arquata and Terek Sandpipers Xenus cinereus) to identify the spatial and temporal variability in coastal inland roost use in the area and the factors influencing the use. We considered the area and length of the standing water in the roost site, temperature, wind speed, the time of migration and the intensity of disturbance. As a result, number of individuals and type of species using the roost site varied across spatial and temporal scales. And the factors affecting the roost use was species-specific. The roost site of the study area was a closed shrimp farm however, it has been converted to a Salicornia herbacea, a salt marsh plant, farm recently. In a situation where coastal inland roost site is needed, we hereby describe a resolution for the juxtaposition of shorebirds and farming.

At-site Low Flow Frequency Analysis Using Bayesian MCMC: I. Theoretical Background and Construction of Prior Distribution (Bayesian MCMC를 이용한 저수량 점 빈도분석: I. 이론적 배경과 사전분포의 구축)

  • Kim, Sang-Ug;Lee, Kil-Seong
    • Journal of Korea Water Resources Association
    • /
    • v.41 no.1
    • /
    • pp.35-47
    • /
    • 2008
  • The low flow analysis is an important part in water resources engineering. Also, the results of low flow frequency analysis can be used for design of reservoir storage, water supply planning and design, waste-load allocation, and maintenance of quantity and quality of water for irrigation and wild life conservation. Especially, for identification of the uncertainty in frequency analysis, the Bayesian approach is applied and compared with conventional methodologies in at-site low flow frequency analysis. In the first manuscript, the theoretical background for the Bayesian MCMC (Bayesian Markov Chain Monte Carlo) method and Metropolis-Hasting algorithm are studied. Two types of the prior distribution, a non-data- based and a data-based prior distributions are developed and compared to perform the Bayesian MCMC method. It can be suggested that the results of a data-based prior distribution is more effective than those of a non-data-based prior distribution. The acceptance rate of the algorithm is computed to assess the effectiveness of the developed algorithm. In the second manuscript, the Bayesian MCMC method using a data-based prior distribution and MLE(Maximum Likelihood Estimation) using a quadratic approximation are performed for the at-site low flow frequency analysis.

A Study on Deterioration of Stone Monuments by Acid Fog (산성안개에 의한 석조문화재 구성암석의 손상 연구)

  • Do, Jin Young;Kim, Sang Woo;Cho, Hyen Goo
    • Journal of the Mineralogical Society of Korea
    • /
    • v.28 no.2
    • /
    • pp.135-145
    • /
    • 2015
  • In order to predict the deterioration of stone monument due to acid fog, an artificial fog test using pH4.0 and pH5.6 was applied to the Gyeongju Namsan granite, decite and marble. After the test had weathered Gyeongju Namsan granite a larger weight reduction due to acid fog than fresh one. Decite has shown the most significant changes among the tested rocks with about 0.005 % of weight reduction. Decite and weathered granite will have considerable weight reduction due to acid rain than the acid fog, whereas the marble was expected to show a weight reduction regardless of the phase of water. The porosity and water absorption rate of weathered granite had significantly increased. This result means that the weathered rock is predicted to be more susceptible to acid fog than the fresh rock. The absorption rate of the marble after the test had shown approximately 50 % increase. The color of the samples had slightly changed towards yellow, such tendency was greater shown in weathered rocks. The marble reacted with acid fog had an increased whiteness. A large amount of cation in the samples is caused mainly by the dissociation of minerals through the reaction with acid fog.

Effects of Thinning on Abundance and Community Structure of Arthropods in a Pinus koraiensis Plantation (잣나무림조림지에서 간벌이 절지동물 풍부도와 군집구조에 미치는 영향)

  • Kwon, Tae-Sung;Yang, Hee-Moon;Shin, Joon-Hwan;Kim, Suk-Kuwon;Yi, Hoon-Bok
    • Korean journal of applied entomology
    • /
    • v.49 no.3
    • /
    • pp.187-198
    • /
    • 2010
  • Thinning treatment has a huge effect on understory and litter structures in forest ecosystem, and the resulting changes may impact some arthropod groups such as plant-feeders and detritivores. This study was carried out to find a change in arthropod abundance and their structures in relation to the thinning activity in a Pinus koraiensis plantation in Chuncheon, Korea, where thinning was conducted twice: in 1998-2000 (old-thinning) and 2007 (new-thinning). Arthropods were collected using pitfall traps in 2006 and 2008. Effects of old-thinning on change of abundance and community structure of arthropod were significant, but the effects of new-thinning were not significant. The most significant thinning effect was found in detritivores, followed by plant feeders, but the effect was hardly significant in predators. Among detritivores the changes in abundance was diverse. The abundance of orthopteran plant-feeder increased, but Curculionidae declined after thinning. There was not different in abundance of total arthropods between thinned and unthinned areas because the difference may have cancelled each other out by increased or decreased abundance of taxa. Community structures of arthropods were most greatly affected by years, followed by the old-thinning, but the new-thinning did not affect community structures.

Development of Recycled Paper Properties using In-Situ Process (In-Situ 공정(工程)을 이용한 재활용(再活用) 펄프의 물성특성(物性特性) 향상 연구(硏究))

  • Lee, Jong-Kyu;Yoo, Kwang-Suk;Nam, Seong-Yong;Ah, Ji-Whan
    • Resources Recycling
    • /
    • v.19 no.3
    • /
    • pp.62-70
    • /
    • 2010
  • As the demand for paper continues to grow and the importance of recycled paper, white ledgar(WL) and old newspaper pulp(ONP), continuously increase. In addition, usage of recycled paper is essential in terms of forest conservation and environmental protection issues. However, optical and mechanical properties of recycled paper have some drawbacks than regular paper's properties that is indispensable. In order to complement these problems of recycled paper, precipitated calcium carbonate (PCC) was synthesized by the In-situ process with a recycled pulp. Depending on the size of PCC is divided into 2 types, $0.01{\mu}m{\sim}0.09{\mu}m$ colloid type ultra-fine particle and $0.1{\mu}m{\sim}0.9{\mu}m$ cubic type particles. In this study, we analyze how the different shape and size of precipitated calcium carbonate affects in the optical and mechanical properties of the recycled paper used as a filler. Furthermore, we mixed with chemical pulp for overcome reduce of mechanical properties, without using other chemicals, when we use PCC as a filler. The results has the possibility to meet in GR excellent recycling certification mark, standard was proposed.

Study on design methods for museum restoration of modern architecture - Centering on cases of restoration modern architecture which fulfilled its epochal function to museum - (근대건축물의 뮤지엄 재생을 위한 디자인방법에 관한 연구 - 시대적 기능을 다한 근대건축물이 뮤지엄으로 재생된 사례를 중심으로 -)

  • Kim, In-Seob;Lee, Sung-Hoon
    • Korean Institute of Interior Design Journal
    • /
    • v.20 no.3
    • /
    • pp.215-224
    • /
    • 2011
  • Throughout the world, interest in issues relevant to energy, resources, environment, etc, is ever soaring. Therefore, the restoration of modern architecture that fulfilled its epochal function is working as a cultural, historic medium. In addition, it also plays its role in the side of environmental approach and so on. Moreover, the museum, which was only used for the possession of art collections and exhibition purposes, is currently expanding its scale and range as the center of culture and education. Also in reality, with the use of various programs, it is globally pursuing urban vitalizations. This study looks at the meaning of modem architecture restoration as well as its relationship with urban area. Furthermore, the purpose of this study is to look for design method's direction by finding the relevance between modem architecture restoration and museum during the restoration. This study is based on transformation and preservation scale during the restoration of modern architecture. It analyzed plane and design direction. Additionally, this study analyzed the architectural and regional effect caused by restoration. As a result, in accordance with the direction of museum and the usage, scale, structure as well as superficial aging condition of previous architecture, it shows difference in design methods in the process of restoration. The exterior of architecture was restored and preserved to its original form in order to show the symbolical form through historical value. This is essential to the modern museum. On the other hand, the interior of architecture put more value on utilization concept that its preservation and thus was restored accordingly. However, in all the cases, previous architecture were commonly used and even when alterations and additions were made due to aging and their change in usage, they were restored in a way that preserved and harmonized previous architecture. If the design method for restoration of modern architecture selects the restoration method by considering problems related to location, building value, structure, if it is studied from various angles and is restored after considering its usage as a museum, then we will be able to generate cultural and historical synergy effect. Furthermore, apart from architecture, it will have great impact on urban vitalizations.

Comparing Laboratory Responses of Engineered Emulsified Asphalt and Foamed Asphalt Mixtures for Cold In-place Recycling Pavement (현장 상온 재생 아스팔트 포장을 위한 고점착 유화 아스팔트 혼합물과 폼드 아스팔트 혼합물의 반응특성 비교)

  • Kim, Yong-Joo Thomas;Lee, Ho-Sin David
    • International Journal of Highway Engineering
    • /
    • v.12 no.1
    • /
    • pp.79-86
    • /
    • 2010
  • Cold in-place recycling (CIR) using emulsified asphalt or foamed asphalt has become a more common practice in rehabilitating the existing asphalt pavement due to its cost effectiveness and the conservation of paving materials. As CIR continues to evolve, the engineered emulsified asphalt was developed to improve the field performances such as coating, raveling, retained stability value and curing time. The main objective of this research is to compare the laboratory responses of the engineered emulsified asphalt (CIR-EE) mixtures against the foamed asphalt (CIR-foam) mixtures using the reclaimed asphalt pavement (RAP)materials collected from the CIR project on U.S. 20 Highway in Iowa. Based on the visual observation of laboratory specimens, the engineered emulsified asphalt coated the RAP materials better than the foamed asphalt because the foamed asphalt is to create a mastic mixture structure rather than coating RAP materials. Given the same compaction effort, CIR-EE specimens exhibited lesser density than CIR-foam specimens. Both Marshall stability and indirect tensile strength of CIR-EE specimens were about same as those of CIR-foam specimens. However, Marshall stability and indirect tensile strength of the vacuum-saturated wet specimens of CIR-EE mixtures were higher than those of CIR-foam mixtures. After four hours of curing in the room temperature, the CIR-EE specimens showed less raveling than the CIR-foam specimens. On the basis of test results, it can be concluded that the CIR-EE mixtures is less susceptible to moisture and more raveling resistant than CIR-foam mixtures.

A Comparison of Machine Learning Species Distribution Methods for Habitat Analysis of the Korea Water Deer (Hydropotes inermis argyropus) (고라니 서식지 분석을 위한 기계학습식 종분포모형 비교)

  • Song, Won-Kyong;Kim, Eun-Young
    • Korean Journal of Remote Sensing
    • /
    • v.28 no.1
    • /
    • pp.171-180
    • /
    • 2012
  • The field of wildlife habitat conservation research has attracted attention as integrated biodiversity management strategies. Considering the status of the species surveying data and the environmental variables in Korea, the GARP and Maxent models optimized for presence-only data could be one of the most suitable models in habitat modeling. For make sure applicability in the domestic environment we applied the machine learning species distribution model for analyzing habitats of the Korea water deer($Hydropotes$ $inermis$ $argyropus$) in the $Sapgyocheon$ watershed, $Chungcheong$ province. We used the $3^{rd}$ National Natural Environment Survey data and 10 environment variables by literature review for the modelling. Analysis results showed that habitats for the Korea water deer were predicted 16.3%(Maxent) and 27.1%(GARP), respectively. In terms of accuracy(training/test) the Maxent(0.85/0.69) was higher than the GARP(0.65/0.61), and the Spearman's rank correlation coefficient result of the Maxent(${\rho}$=0.71, p<0.01) was higher than the result of GARP(${\rho}$=0.55, p<0.05). However results could be depended on sites and target species, therefore selection of the appropriate model considering on the situation will be important to analyzing habitats.

A Study on the Removal of Ammonia by Using Peat Biofilter (미생물 활성토탄을 이용한 암모니아 제거에 관한 연구)

  • Choung, Youn Kyoo;Ahn, Jun Seong
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.14 no.3
    • /
    • pp.655-668
    • /
    • 1994
  • Conventional deodorization filters using soil and compost reach the capacity limitation of deodorization in short period, because its removal mechanism primarily depends on adsorption. Therefore, in this study the experiment was performed on the removal of ammonia which is a strong inorganic malodor, frequently emitted from night soil treatment plants and sewage treatment plants, by seeding activated sludges on the bio-peat containing higher organic contents, water conservation capacity, permeability and lower pressure drop. As a result, in raw peat filter natural ammonia outlet was observed in consequence of pH increase resulted from ammonia ionizing in liquid phase. Ammonia removal mechanism primarily depended on the adsorption onto the anion colloidal substances in peat. In peat bio-filter, theoretical ammonium salts ratio was higher than that of raw peat, resulted from slight pH increase by microorganism activity, however, the experimetal value of ammonia-nitrogen accumulated in bio-peat was lower than that of raw peat because of nitrification by nitrifying bacteria. In the initial reaction period, adsorption was predominant in the ammonia removal mechanism, but nitrification was conspicuous after the middle period. Mass balance of nitrogen was established using experimental data of input $NH_3$ loading, output $NH_3$ loading, $NH_4{^+}$-N, $NO_x$-N, and Org-N. The critical time of unsteady state, which is the maximum activating point of microorganism in bio-filter, was determined using experimental data, and the ammonia adsorption curve was computed using regression analysis. On the basis of the results obtained by above analysis, the delay days for the saturation of adsoption capacity in peat bio-filter was calculated.

  • PDF

Modeling of the charge and discharge behavior of the 2S2P(2 series-2 parallel) AGM battery system for commercial vehicles (상용자동차용 직·병렬 AGM 배터리 시스템의 충·방전 거동 모델링)

  • Lee, Jeongbin;Kim, Ui Seong;Yi, Jae-Shin;Shin, Chee Burm
    • Journal of Energy Engineering
    • /
    • v.21 no.4
    • /
    • pp.346-355
    • /
    • 2012
  • Recent in the world environmental issues and energy depletion problems have been received attention. One way to solve these problems is to use hybrid electric vehicles (HEVs). Therefore, the interest in HEV technology is higher than ever before. Viable candidates for the energy-storage systems in HEV applications may be absorbent glass mat (AGM) lead-acid, nickel-metal-hydride (Ni-MH) and rechargeable lithium batteries. The AGM battery has advantages in terms of relatively low cost, high charge efficiency, low self-discharge, low maintenance requirements and safety as compared to the other batteries. In order to implement HEV system in required more electric power commercial vehicles AGM batteries was connected to 2 series-2 parallels (2S2P). In this study, a one-dimensional modeling is carried-out to predict the behaviors of 2S2P AGM batteries system during charge and discharge. The model accounts for electrochemical reaction rates, charge conservation and mass transport. In order to validate the model, modeling results are compared with the experimentally measured data in various conditions.