• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.124-128
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• 1999

The photochemistry of the derivatives of o-nitrobenzylcarboxyl esters or benzylsulfonyl derivatives has been well studied separately. But little attempt has been made to combine the fruits these two studies. Being photochemically active, benzylsulphonyl and intro groups should influence the reactivity of each other's, especially when the excited states are fully mixed due to the proximity of their location. The questions which should be clearly answered are; what kind of effect will be excerted to the other group, and whether these two functional groups are coupled in the course of the reaction. To answer the questions raised above, wer have synthesized two sulfonyl esters and four amides from the newly available starting material, 2-nitro-${\alpha}$-toluenesulfonyl chloride. The products identified from the exploratory solution photochemistry were cyclohexanol, phenol, cyclohexylamine, and sulfur dioxide. The results are not much different from the products originally anticipated. It has been temporarily concluded that there is little interaction between the benzyl sulfonyl group and ortho-nitro chromophore. The fact that a base (an amine) has been photochemically generated in solution photochemistry was further confirmed by and utilized in the solid phase quantitative photochemistry done on the film, so as to carry out the photochemical epoxide cure.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.31-39
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• 2007

Monitoring data of 48 agricultural irrigation reservoirs from 1999 to 2004 was analyzed for water quality characteristics including biochemical oxygen demand $(BOD_5)$, chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and chl-${\alpha}$. Land uses of the watersheds associated with these reservoirs were determined for residential, forest, upland, paddy and miscellaneous, and regressed against water quality characteristics. Correlation analysis showed that forest land use was negatively correlated with all the water quality characteristics implying it's beneficial effects in water quality perspectives. Other land uses including residential, upland, and paddy generally illustrated positive correlation with water quality characteristics, which indicates most human activities of the watershed could degrade water quality of the receiving water bodies. Paddy land use partially contributed to the water quality degradation in contrast to the previous studies. It might be attributed to the relatively clean water quality of the study area, where even slight pollutant loading could degrade sensitively water quality. Further investigation is recommended for the effect of proximity as well as land use portions on the water quality of receiving water body.

• Journal of Environmental Impact Assessment
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• v.25 no.6
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• pp.457-465
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• 2016

Around the world, a lot of people are migrating to the urban areas, and new cities are continuously being constructed. Currently about 54 percent of the world's population live in the urban areas, and by 2050, it is expected to increase to 66 percent; thus, managing the urban areas is one of the most important challenges of sustainable development in the 21st century. The key to successful urban management is to preserve the urban green spaces, which provide aesthetic, psychological and health benefits to the urban citizens. However, the benefits of the urban green spaces are not fully appreciated within the societies due to the difficulty of economic valuation of the urban green spaces. This study examined whether the view of the Songdo Central Park has a positive influence on the prices of the surrounding apartments, using the hedonic pricing method. The results showed that a positive relation exists between the view of the Songdo Central Park and the price of apartment. The price of an apartment with the view of the Songdo Central Park was 5 percent higher than that of an apartment without the view. In addition, it was estimated that the proximity to the Songdo Central Park has an influence on the housing price as well.

• The Journal of the Korea Contents Association
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• v.18 no.7
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• pp.590-599
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• 2018

As a basic information to implement the fire plan that dominates multiple targets effectively under the battle environment with limited resources, such a process is mandatory that gives a priority order to a target with the high level of threat by quantitatively computing the threat level of an individual target through the analysis on the target. However, the study has still remained in the initial level on an evaluation algorithm for the threat level of the ground target. Considering this fact, the present paper proposes the evaluation algorithm for the threat by multiple ground targets. The proposed algorithm has a core point to consider the type of target and protected asset to implement the computation of proximity; set the additional value based on the weights indicating the significance of weapon and protected asset; and compute the threat level of a target that considers the characteristics of the target. The evaluation and verification of performances have been implemented through the simulation and visualization of an algorithm proposed in the present paper. From the performance result, as the proposed algorithm has been able to perform effectively the threat assessment according to the weights indicating the significance of weapons and protected assets under diverse environments where weapons and protected assets are located, high utility and effect are expected when applied to an actual ground weapon system.

• Korean Journal of Construction Engineering and Management
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• v.16 no.5
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• pp.77-85
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• 2015

The Hedonic Pricing model is the predominant approach used today to model the effect of relevant factors on real estate prices. These factors include intrinsic elements of a property such as floor areas, number of rooms, and parking spaces. Also, The model also accounts for the impact of amenities or undesirable facilities of a property's value. In the latter case, euclidean distances are typically used as the parameter to represent the proximity and its impact on prices. However, in situations where multiple facilities exist, multi-colinearity may exist between these parameters, which can result in multi-regression models with erroneous coefficients. This research uses Variance Inflation Factors(VIF) and Ridge Regression to identify these errors and thus create more accurate and stable models. The techniques were applied to apartments in Guro-gu of Seoul, whose prices are impacted by subway stations as well as a public prison, a railway terminal and a digital complex. The VIF identified colinearity between variables representing the terminal and the digital complex as well as the latitudinal coordinates. The ridge regression showed the need to remove two of these variables. The case study demonstrated that the application of these techniques were critical in developing accurate and robust Hedonic Pricing models.

• Journal of the Korean Geographical Society
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• v.36 no.4
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• pp.356-381
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• 2001

This study has three objectives. One of them is to debate on the incompatible Neo-Malthusianism and Comucopianism, which give us a comparative gauge for analysis of the population elements in Korea and Japan. The other is to investigate how a variety of population elements are related to specific regions, Korea and Japan. And the last is to compare and analyze the residential preference pattems and the degree of care for the future life for the aged over 50 ages. Various elements in population show that Japan is of type superior to Korea, and that the gap between two countries is getting narrow every year. Wiber's migration expectancy is much higher in Kwangiu-si and Chollanam-do than in Hiroshima-ken. Burial customs in funeral ceremony has been vanished in Japan, but only 30 percents in Korea is crematory. This burial customs being much stiff existent in Korea, the effect of the population decrease caused by the death is reduced. A case study through questionnaire on the residential preference patterns for the aged over 50 years old shows that Japanese than Korean are more dependent on their sons and daughters, and ‘loneliness of solitary life’is the first reason in both countries. The degree of care for the future life is also remarkably higher in Japanese than in Korean. These are related in various ways to their ages, scholarships and local areas(si or gun). A general cognition in which the shortage of labour forces comes into existence in aged society is of misconception, because it comes from taking labour forces away from the aged, not from being old society. Even a minute population change is worth notice since the inertia law is also applied to the population phenomenon. Malthusinism hold fairly good even now, and the notion is very important in which population, resources and environmental problems are no longer personal or a regional matters, but the global family's issues.

• Journal of Photoscience
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• v.11 no.32
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• pp.71-74
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• 2004

The macrocycle L exhibited a switch on-off behavior through the fluorescent responses by aromatic imine molecule 1 (X=H) / trifluoroacetic acid (TFA). In the 'switch on' state, it was supposed that the aromatic imine molecule 1 is in the cavity of macrocycle L and a photoinduced electron transfer (PET) from the nitrogen of azacrown part to the anthryl group is inhibited by the interaction between the aromatic imine molecule 1 and the azacrown part of macrocycle L. In the 'switch off' state, it was supposed that the protonated imine molecule 1 is induced by the continuous addition of TFA and a repulsion between the protonated azacrown part and the protonated imine molecule 1 is occurred. It was considered that this process induces the intermolecular PET from the protonated imine molecule 1 to the anthryl group of macrocycle L because of a proximity effect between the anthryl group and the protonated imine molecule 1. From the investigation of the transient emission decay curve, the macrocycle L showed three components (3.45 ns (79.72%), 0.61 ns (14.53%), and 0.10 ns (5.75%). When the imine molecule 1 was added in the macrocycle L as molar ratio=1:1, the first main component showed a little longer lifetime as 3.68 ns (82.75%) although the other two components were similar as 0.64 ns (14.28%) and 0.08 ns (2.96%). On the contrary, when the imine molecule 3 (X=C1) was added in the macrocycle L as molar ratio=l:1, all the three components were decreased such as 3.27 ns (69.83%), 0.44 ns (13.24%), and 0.06 ns (16.93%). The fluorescent pH titration of macrocycle L was carried out from pH=3 to pH=9. The macrocycle L and C $U^{2+}$- macrocycle L complex were intersected at about pH=5, while the E $u^{3+}$ -macrocycle L complex was intersected at about pH=5.5. In addtion, we investigated the fluorescence change of macrocycle L as a function of the substituent constant ($\sigma$$_{p}$$^{o}$) showing in the para-substituent with electron withdrawing groups (X=F, Cl) and electron donating groups (X=C $H_3$, OC $H_3$, N(C $H_3$)$_2$), respectively, as well as non-substituent (X=H).).ctively, as well as non-substituent (X=H).

• Investigative Magnetic Resonance Imaging
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• v.16 no.2
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• pp.159-168
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• 2012

The proximity of thoracic aortic aneurysm to the left subclavian artery (LSA) has made the coverage of LSA during thoracic endovascular aortic repair (TEVAR) be essential. Despite controversy concerning the safety of LSA coverage and the indications for LSA revascularizations, the cerebral hemodynamic change after LSA coverage has not been demonstrated. We prospectively examined two patients who would undergo TEVAR with LSA coverage by using 2D cine phase contrast MR imaging. After LSA coverage, the left subclavian steal was properly compensated by the increased flow volumes of both carotid arteries and right vertebral artery, which is the major collateral supply. The total brain supply after TEVAR did not lessen, which showed good correlation with uneventful clinical outcome. Therefore, 2D phase contrast MR imaging can be recommended as a useful technique to evaluate the hemodynamic change of the LSA coverage during TEVAR and to triage the candidate for LSA revascularization.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.647-662
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• 2015

This study analyzes the factors that influence the number of public transportation passengers. By comparing the major TOD planning elements such as mixed-use level, job-housing proximity level, comparison of the density and pure density in the 66-autonomous city townships through a comparison such as TOD plan element achievements and indicators are chosen. A model is derived by correlation analysis and regression analysis of the parameters. The result of the regression analysis of the station influence area (SIA) in Incheon, the parameters that effect the number of passengers of public transportation are the number of employees, population, number of bus stops in the SIA, and the distance between the bus stop and the subway entrance. Therefore, as the number of employees and the resident population increase, the volume of traffic increases. Also, the number of public transportation users increases when there are more bus stops and when the distance between the bus stop and the subway entrance is short. This study shows that subways and SIA has achieved many parts of the TOD in Incheon, because the SIA around 29 subways and 11 Seoul-Incheon trail stations already included important TOD planning elements.

• Journal of Korea Water Resources Association
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• v.40 no.7
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• pp.571-583
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• 2007

The effects of climatic changes owing to urbanization, geographical and topographical conditions on Penman-Monteith reference evapotranspiration, and energy and aerodynamic terms of Penman-Monteith reference evapotranspiration have been studied. In this study, 56 climatological stations including the Seoul metropolis in South Korea have been selected, and the area of study site was set at $314\;km^2$. The climatological station is centrally located In the study area with a 10 km radius. The geographical and topographical characteristics of these sites were examined using GIS analysis. Land use status of the study area was also examined to estimate the extent of urbanization. The study results indicated that the variation of reference evapotranspiration rate is closely related to urbanization in most climatological stations. The level of change in reference evapotranspiration was higher in areas with higher urbanization rates. The change in reference evapotranspiration appears to be caused by temperature rises following heat island phenomena due to urbanization, and by the decrease in humidity, wind speed and sunshine duration due to the Increase in residential areas in urban districts. Especially, the humidity decrease causes a significant decrease in evapotranspiration rate. The study results showed that climatic change due to urbanization and proximity to the coast had the greatest effect on reference evapotranspiration.