• Journal of the Korean Institute of Landscape Architecture
• /
• v.51 no.1
• /
• pp.42-55
• /
• 2023

A methodology to predict the carbon performance of newly created urban greening plans is required as policies based on quantifying carbon performance are rapidly being introduced in the face of the climate crisis caused by global warming. This study developed a tree carbon calculator that can be used for carbon reduction designs in landscaping and attempted to verify its effectiveness in landscape design. For practical operability, MS Excel was selected as a format, and carbon absorption and storage by tree type and size were extracted from 93 representative species to reflect plant design characteristics. The database, including tree unit prices, was established to reflect cost limitations. A plantation experimental design to verify the performance of the tree carbon calculator was conducted by simulating the design of parks in the central region for four landscape design, and the causal relationship was analyzed by conducting semi-structured interviews before and after. As a result, carbon absorption and carbon storage in the design using the tree carbon calculator were about 17-82% and about 14-85% higher, respectively, compared to not using it. It was confirmed that the reason for the increase in carbon performance efficiency was that additional planting was actively carried out within a given budget, along with the replacement of excellent carbon performance species. Pre-interviews revealed that designers distrusted data and the burdens caused by new programs before using the arboreal carbon calculator but tended to change positively because of its usefulness and ease of use. In order to implement carbon reduction design in the landscaping field, it is necessary to develop it into a carbon calculator for trees and landscaping performance. This study is expected to present a useful direction for ntroducing carbon reduction designs based on quantitative data in landscape design.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.25 no.3
• /
• pp.63-71
• /
• 2017

In this study, washing parameters such as washing time, agitation velocity, and cycles were optimized for high surface area of the activated carbon (AC) by KOH activation. Even though AC with high surface area showed at higher washing efficiency, over 90% on washing efficiency was regulated by the intra-particle diffusion due to high tortuosity of the pore structures on AC. In addition, we can obtain $K_2CO_3$ through the evaporation from the wastewater and use it for chemical activation of AC. The AC with $K_2CO_3$ activation has specific surface area values of $2,219m^2/g$ equally that of KOH activation. Considering that $K_2CO_3$ is an effective alternative as a KOH, our results demonstrated that the process by recycling wastewater on AC production could be applicable for near-zero wastes.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.7 no.3
• /
• pp.227-234
• /
• 2005

From published data of mature forests worldwide, Raich and Nadelhoffer suggested that total belowground carbon allocation (TBCA) could be estimated from the difference between annual rates of soil respiration and aboveground litterfall. Here we analyze new measurements of IRGA-based soil respiration and litterfall of natural mature oak forests dominated by Quercus mongolica in Korea. Rates of in situ soil respiration and aboveground litter production are highly and positively correlated. Our results disagree with the Raich and Nadelhoffer model far world forests. A regression analysis of the data from Q. mongolica forests produced the following relationship: annual soil respiration : 141 + 2.08 ${\times}$ annual litterfall. The least squares regression line has a more gentle slope (2.08) than the slope (2.92) described by Raich and Nedelhoffer for mature forests worldwide. The regression slope of our study indicates that, on average, soil respiration is about two times the aboveground litterfall-C, which further implies that TBCA is similar with annual aboveground litterfall-C at natural Q. mongolica forests in Korea. The non-zero Y-intercept (141) of the regression indicates that TBCA may be greater than litterfall-C where litterfall rate are relativery low. Over a gradient of litterfall-C ranging from 200-370 g C $m^{-2}yr^{-l}$, TBCA increased from 350-530 g C $m^{-2}yr^{-l}$.

• Journal of Welding and Joining
• /
• v.24 no.4
• /
• pp.32-38
• /
• 2006

The objective of present research works is to investigate the effects of process parameters, including the power of laser, cutting speed, material thickness, and the edge angle, on the melted area in the sharp edge of the cut material fur the case of cutting of a low carbon steel sheet using high-power CW Nd:YAG laser. In order to investigate the influence of edge angle and size of loop on the melted area in the sharp edge, angular cutting tests and loop cutting tests have been carried out. From the results of angular cutting tests, the relationship between the edge angle and the melted area has been obtained. The results of the experiments have been shown that the melted area is rapidly reduced from $120^{\circ}$ of the edge angle and the melted area is nearly zero at $150^{\circ}$ of the edge angle. Through the results of loop cutting experiments, the relationship between the cutting angle on the melted area in the edge according to the size of loop have been obtained. In addition, it has been shown that a proper size of loop is nearly 3 mm as the corner angle is greater than $90^{\circ}$ and 5 mm as the comer angle is less than $90^{\circ}$. The results of above experiments will be reflected on the knowledge base to generate optimal cutting path of the laser.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.35 no.3
• /
• pp.251-256
• /
• 2015

The study was conducted to determine greenhouse gas (GHG) inventories in grasslands. After 'Low Carbon Green Growth' was declared a national vision on 2008, Medium-term greenhouse gas reduction was anticipated for 30% reduction compared to Business As Usual (BAU) by 2020. To achieve the reduction targets and prepare to enforce emissions trading (2015), national GHG inventories were measured based on the 1996 Intergovernmental Panel on Climate Change Guidelines (IPCC GL). The national Inventory Report (NIR) of Korea is published every year. Grassland sector measurement was officially added in 2014. GHG removal of grassland soil was measured from 1990 to 2012. Grassland area data of Korea was used for farmland area data in the "Cadastral Statistical Annual Report (1976~2012)". Annual grassland area corresponding to the soil classification was used "Soil classification and commentary in Korea (2011)". Grassland area was divided into 'Grassland remaining Grassland' and 'Land converted to Grassland'. The accumulated variation coefficient was assumed to be the same without time series changes in grassland remaining grassland. Therefore, GHG removal of soil carbon was calculated as zero (0) in grassland remaining grassland. Since the grassland area increases constantly, the grassland soil sinks constantly . However, the land converted to grassland area continued to decrease and GHG removal of soil carbon was reduced. In 2012 (127.35Gg $CO_2$), this removal decreased by 76% compared to 1990 (535.71 Gg $CO_2$). GHG sinks are only grasslands and woodlands. The GHG removaled in grasslands was very small, accounting for 0.2% of the total. However, the study provides value by identifying grasslands as GHG sinks along with forests.

• Korean Journal of Crystallography
• /
• v.6 no.2
• /
• pp.111-117
• /
• 1995

TiO2 thin films were prepared on a (100)silicon wafer using a chemical vapor deposition(CVD) method. The deposition experiments were performed using the TTIP in the deposition temperature ransing from 200 content. The deposition rate of TiO2 was increased with the substrate temperature and the oxygen content. The thickness of the deposited thin film and the compositional analysis of this thin films with theoxygen content were measured using Ellipsometry, SEM and ESCA, respectively. The deposited thin film was composed of a bilayer, external TiO2 and internal Ti. Carbon as a residual impurity was found to remain when zero sccm O2 was purged into a reaction chamber and the composition of the deposited thin film was found to change Ti into TiO in a deeper layer. However, when 600sccm O2 was supplied to a reaction chamber, it has been found to reside less carbon content than without O2. Finally, in the condition of 1200sccm O2, no impurity level of carbon was observed and a deeper layer consisted of the Ti composite, even though the deposited surface was composed of TiO2.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.2
• /
• pp.359-366
• /
• 2021

It's been more than 30 years since global warming by the increase in CO2 became a cause celebre worldwide. Recently the government promulgated Framework Act on on Low-Carbon Green Growth and has been continuously putting much effort into saving energy and reducing carbon dioxide emissions such as an international climate change conference to prevent the increase in CO2. However, because most cities are not planned for energy saving, new cities should be planned as the active energy-efficient urban structure for 'sustainable urban development' from a long-term perspective. This study aims to design a new prototype for the sustainable energy-independent and environment-friendly housing estates which is the nation's new vision in the era of the Fourth Industrial Revolution. A study on the energy-independent site planning and the quantitative standardization of its factor will be conducted.

• Land and Housing Review
• /
• v.2 no.4
• /
• pp.429-437
• /
• 2011

The purpose of this research is to seek the suggestions applicable to Korean green-growth(development) policy and the realization of low carbon society by looking around the promotion policy and the process, the promotion system, main environmental policy in each city about the business for environmental model city in Japan which has been promoted in a city in order to realize low-carbon society. Japan had selected 13 local governments as an environmental model city as a part of a policy to build low-carbon society in 2008~2009, and Japan has formed information sharing between cities and provinces, the spread of information sharing and the free competition among local governments for an environmental model city through Zero Carbon City Promotion Council consisting of local governments and specialists. When examining these cases in Japan, the green-growth policy promoting currently in Korea needs to be converted from the central government-dominated policy to the local government-dominated policy and Koreaneeds to make more effort to develop software programs in order to realize green-growth social system.

• Journal of Soil and Groundwater Environment
• /
• v.17 no.2
• /
• pp.15-21
• /
• 2012

MTBE (Methyl tertiary-butyl ether) has been commonly used as an octane enhancer to replace tetraethyl lead in gasoline, because MTBE increases the efficiency of combustion and decreases the emission of carbon monoxide. However, MTBE has been found in groundwater from the fuel spills and leaks in the UST (Underground Storage Tank). Fenton's oxidation, an advanced oxidation catalyzed with ferrous iron, is successful in removing MTBE in groundwater. However, Fenton's oxidation requires the continuous addition of dissolved $Fe^{2+}$. Zero-valent iron is available as a source of catalytic ferrous iron of MFO (Modified Fenton's Oxidation) and has been studied for use in PRBs (Permeable Reactive Barriers) as a reactive material. Therefore, this study investigated the condition of optimization in MFO-PRBs using waste zero-valent iron (ZVI) with the waste steel scrap to treat MTBE contaminated groundwater. Batch tests were examined to find optimal molar ratio of MTBE : $H_2O_2$ on extent to degradation of MTBE in groundwater at pH 7 with 10% waste ZVI. As the results, the ratio of optimization of MTBE to hydrogen peroxide for MFO was determined to be 1:300[mM]. The column experiment was conducted to know applicability of MFO-PRBs for MTBE remediation in groundwater. As the results of column test, MTBE was removed 87% of the initial concentration during 120days of operational period. Interestingly, MTBE was degraded not only within waste ZVI column but also within sand column. It means the aquifer may affect continuously the MTBE contaminated groundwater after throughout the waste ZVI barrier. The residual products showed acetone, TBF (Tert-butyl formate) and TBA (Tert-butyl acetate) during this test. The results of the present study showed that the recycled materials can be effectively used for not only a source of catalytic ferrous iron but also a reactive material of the MFO-PRBs to remove MTBE in groundwater.

• Journal of the korean society of oceanography
• /
• v.32 no.2
• /
• pp.69-74
• /
• 1997

Depth profiles of organic carbon (C), biogenic silica (Si), and inorganic phosphorus (P) in Maxwell bay sediments were determined to investigate paleoclimatic changes during Holocene. Organic C and biogenic Si contents generally show a down-core decrease trend, which appears to be mostly controlled by their vertical fluxes through productivity in the surface waters, but it is uncertain that inorganic P contents are directly influenced by productivity changes with time. Before 4000 yr B.p. marine productivity seemed to be almost zero because ice permanently covered the surface waters of the study area. As the climate started to become relatively warm at 4000 yr B.p., ice was sporadically melted in the surface waters and thereby marine productivity gradually increased until 1500 yr B.p. For the last 1500 year, marine productivity must be high enough to overcome the dilution by high terrigenous sedimentation, thus that period was the warmest during the last 6000 year.