• Korean Journal of Remote Sensing
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• v.38 no.4
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• pp.411-419
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• 2022

DPR Korea has been creating cropland across the country due to its chronic food shortage. Cropland was about 17.4% at the end of the 1980s, but it increased steadily to 19.6% at the end of the 1990s, 24.8% at the end of the first decade of 2000s, and 25.4% at the end of the 2010s. On the other hand, the forest land declined from about 74.8% in the late 1980s to 69.5% in the late 2010s. Urbanization is also progressing, increasing from about 1.15% at the end of the 1980s to 1.68% at the end of the 2010s. Most of the deforestation that occurred in DPR Korea was caused by conversion to cropland. These characteristics of land cover changes in DPR Korea provide useful information and implications for international and inter-Korean cooperation for DPR Korea.

• Construction Engineering and Management
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• v.13 no.2
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• pp.18-20
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• 2012

• Journal of the Korean Statistical Society
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• v.36 no.2
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• pp.299-320
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• 2007

We introduce a high breakdown point estimator referred to as data partitioning robust regression estimator (DPR). Since the DPR is obtained by partitioning observations into a finite number of subsets, it has no computational problem unlike the previous robust regression estimators. Empirical and extensive simulation studies show that the DPR is superior to the previous robust estimators. This is much so in large samples.

• Journal of the Korean Geographical Society
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• v.49 no.2
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• pp.264-274
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• 2014

The main purpose of the current research is to analyze DPR Korean carbon emissions due to forest loss and to identify potential project sites for REDD implementation. REDD (Reducing Emissions from Deforestation and forest Degradation) is a global environmental policy that is geared towards lowering carbon emissions in developing and least developed countries through saving forests that are vulnerable to future deforestation. DPR Korea is known for its underdevelopment as well as its serious environmental degradation, but limited research exists regarding these issues. The research employs remotely sensed global data and forest carbon stock information from the existing literature to quantify carbon emissions in DPR Korea. It turns out that the country may have had emitted about 82.6 to 149.3 $MtCO_2e$ due to forest loss between 2005 and 2009. A few administrative districts are delineated as prospective REDD sites, of which the outcomes of Local Moran's I represent high rates of deforestation. In brief, it appears there is a great possibility to lower carbon emissions in DPR Korea via REDD implementation.

• Toxicological Research
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• v.17 no.2
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• pp.91-96
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• 2001

Phthalates are widely used as plasticizers to impart softness and flexibility to normally rigid polyvinylchloride products. However, there are not much studies jar dermal and ocular irritation toxicity of phthalates. So we investigated the skin or eye irritation effect of some phthalates which was not reported. The primary skin irritation of diethyl phthalate (DEP), diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), dipropyl phthalate (DPP) and dipropyl phthalate (DPrP) was studied. The ocular irritation of dibutyl phthalate(DBP), DIDP, DINP, DPP and DPrP was also studied. DEP, DIDP, DINP, DPP, and DPrP were found to be non-irritating to the skin of the test animals. DBP, DIDP, DINP and DPP were found to be non-irritating to the eye of the rabbits. DPrP caused the slight irritations to the eye in 1 or 2 days after treatment but irritation of the animals was soon recovered.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1244-1250
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• 2000

A method for simultaneous quantitative determination of plasticizers such as diethyl phthalate(DEP), di-n-propyl phthalate(DprP), di-n-butyl phthalate(DBP), di-n-pentyl phthalate(DPP), butylbenzyl phthalate(BBP), di-(2-ethylhexyl) phthalate(DEHP), dicyclohexyl phthalate(DCHP) and di-(2-ethylhexyl) adipate(DEHA), which are suspected as endocrine disruptors, in food was studied. A analysis method was optimized for the quantification of plasticizers in Jjambbong, which is a kind of fatty noodle, by using GC/FID. The detection limits of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 3.5, 5.3, 2.2, 2.2, 7.2, 1.7, 1.9 and 3.0 mg/kg, respectively. Much higher recovery was obtained by extraction with acetone/n-hexane(1:1) rather than hexane solvent system. The recovery of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 72.7, 85.9, 91.4, 97.1, 100.8, 103.2, 104.3 and 95.8% after 4 time extractions, respectively. The migration of plasticizers from PVC wraps into PVC wrap covered Jjambbong was conducted after shaking(120 rpm) for 30min at room temperature with chosen solvent system. It was found that the migration level of DEHA were 577, 706, 770 mg/kg into Jjambbong, respectively, while the other plasticizers were not observed.

• Korean Journal of Construction Engineering and Management
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• v.13 no.4
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• pp.100-109
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• 2012

Large road construction projects are typically partitioned into sections that are then contracted individually to contractors. Each section requires using similar heavy equipment including excavators, dump trucks and pavers, which constitute the highest cost. Normally the equipment is not shared between them, as each contractor wishes to have their equipment readily available. However, such practices result in very low utilization of these equipment. The goal of this research is to develop a programmatic resource sharing system in which contractors can share equipment depending on the changing needs of a multi-sectioned road project. This paper introduces the results of a survey performed to investigate how contractors currently manage the supply and demand of equipment and the equipment that are practical for sharing across a project. More importantly, the paper describes a set of metrics (DPR, nDPR, SDI) needed to quantify the amount of supply/demand variance occurring in each section. The metrics were used on an actual road construction project, and the results show that each section suffers from an imbalance between its monthly planned and actual utilization of equipment. The results also indicate that the sharing of the equipment can lead to potentially large savings as equipment requirements can be met within a project as to short leasing from outside vendors.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2008.11a
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• pp.59-66
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• 2008

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.41-46
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• 2000

The level of plasticizer such as diethyl phthalate (DEP), di-n-propyl phthalate (DprP), di-n-butyl phthalate (DBP), di-n-pentyl phthalate (DPP), butylbenzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP), dicyclohexyl phthalate (DCHP) and di-(2-ethylhexyl) adipate (DEHA) was determined in disposable sanitary gloves. Samples of disposable sanitary gloves were taken at retail shops, and their overall extractions in carbon tetrachloride were measured, after establishment of soxhlet appratus in 6 hours. All of 8 samples of disposable sanitary gloves at retail shops were polyethylene (PE). All of the manufactures was voluntarily labelled their boxes of gloves in line Korea Food Code. The level of phthalate esters and DEHA in all of 8 samples were not exceed the detection limit. The detection limits of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 1.8, 1.9, 1.3, 1.1, 0.9, 0.7, 2.1 and 0.8 mg/L, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.1
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• pp.29-43
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• 2002

The purpose of this paper is to examine atmospherical factors affecting user's satisfaction in natural park to answer the research question: what are the effects of atmosphere on user's satisfaction in natural parks(NP). After reviewing the literature, mechanism of NP, and use elements in NP, We constructed the conceptual framework and have formulated the hypothesis of this research. We had obtained data through a questionnaire, which surveyed 508 visitors at 6 of the 73 NP in Korea in 2001, based on stratified sampling method. We have analyzed the data using descriptive statistical methods, the mean difference test, Pearson's correlation analysis, and the multiple linear regression method. We found that 1) the five atmospheric variables, j.e., number of users(NOU), crowding, damage to park resources(DPR), and maintenance of park resources and facilities(MPRF), encounter level(EL) affecting user's satisfaction, have tuned out to be statistically significant at a five percent level. The direction of the relationship between user's satisfaction and MPRF, NOU, EL is the same as that of the dependent variable and the opposite of crowding, and BPR, 2) in bivariate analysis, the positive relationships between user's satisfaction and park resources, MPRF are fairly high and statistically significant. The higher the value of DPR, and crowing, the lower the degree of user's satisfaction, 3) in multivariate analysis, such variables as NOU, crowding, DPR, EL, and MPRF affecting user's satisfaction have been statistically significant at five percent level, and 4) the relative contribution of MPRF, park resources, park facilities, NOU, crowding, DPR, and size of activity space on user's satisfaction have been determined to have respectively 6.00, 4.78, 2.53, 1.83, 1.64, 1.59 and 2.03 times more important than that of EL. Among the atmospheric variables, MPRF is the most important at 1.26 times higher than that of park resources. The research results suggest that the development of devices for the increase in user's satisfaction and user management program based on the knowledge we have found, be recommended in the planning and development process of natural park. The approach adopted by this research is valid and useful for evaluation criteria of NP. It is recommended that more empirical studies by activity types, activity spaces, and seasons on atmospheric elements affecting user's satisfaction be performed in the future.