• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5551-5557
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• 2012

Sedimentary rocks dug up in construction fields are mostly stockpiled for landfill disposal, leading to an increase in construction costs and construction inefficiency. After screening, some of the sandstone can be used as aggregate; however, most of the shale ends up as industrial waste in practice. In this study, to stabilize the demand and develop resources for alternative aggregates of concrete, the potential use of shale, which is widely distributed in the Daegu-Kyeongbuk region, as a concrete aggregate was evaluated. Red and black shale exported from a Daegu excavation site was selected for use in the experiments and evaluated by comparing with hornfels, which is widely used as a coarse aggregate and is a type of andesite and metamorphosed sedimentary rock. The physical properties of the aggregate were evaluated in accordance with the test methods of KS F 2527 "crushed concrete aggregate," and the compressive strength against the shale aggregate replacement ratio was measured. The compressive strength of the concrete after 28 days was 30.8 MPa when the black shale replaced 100% of the aggregate in the concrete and 31.1 MPa when the red shale replaced 100% of the aggregate in the concrete. Compared with the compressive strength of 37.5 MPa for concrete prepared by using plain aggregate, using shale as a substitute for the aggregate produced an average compressive strength that was 82% of normal concrete.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5637-5645
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• 2012

To enhance the reutilization of waste skate skin for the functional food resources, the investigations of extraction characteristics, antioxidative activity of skate skin water extracts on the oxidation of three cooking oils were carried out, and rheological properties, storage safety and sensory evaluation of collagen gel from skate skin were performed. Aromatic and phenolic compounds contents of $50^{\circ}C$ extracts were higher by 49.4% and 32.7%, respectively, than those of $25^{\circ}C$ extracts. Reducing power of extract at $50^{\circ}C$ was higher by 52.74% than that of $25^{\circ}C$ extract, but was 14.9% of ascorbic acid and 27.8% of BHT. Electron donating ability was corresponded to reducing power and phenolic compounds contents. Antioxidative effect of extracts on cooking oil was higher at $50^{\circ}C$ extract than $25^{\circ}C$ extract, and its order was on corn seed oil, soybean oil and olive oil. Antioxidative effect of $50^{\circ}C$ extract showed 38.27~96.83% and 49.53~75.31% of those of ascorbic acid and BHT, respectively, over three cooking oil. The optimum extraction condition for collagen gellation was $100^{\circ}C$, 2 hours extraction under 2.5 folds hydrolysis, and gel strength was lowered above 50% by 10% seasoning.

• KDI Journal of Economic Policy
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• v.12 no.3
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• pp.95-123
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• 1990

Advertising, while providing a linkage between sales and consumption, helps promote rational consumption patterns by expanding the scope of information for consumers facing an ever-increasing array of consumption decisions. In so doing, advertising promotes competition among suppliers and sellers, thereby improving market transparency. Intrinsically, advertising can influence the instantaneous decisions made by consumers, and because of this peculiar feature of advertising, ensuring fair advertising practices is a policy issue of great importance. Concurrently, discerning whether the amount of advertising, which is determined by the profit motive of advertisers, is socially appropriate or whether this amount constitutes a waste of scarce resources is a necessary and indispensable consideration in establishing a public policy to respond to the mounting deluge of advertising. Although the Fair Trade Act and numerous other related laws are being enforced with regard to advertising, it may be difficult to say that a unified, practicable and logical basis for regulating the variegated and complex forms of advertising has been established. This paper examines the various theoretical arguments on the welfare effects of advertising as a rationale to justify regulation from the viewpoint of economics. In this manner, this paper helps define the essential nature of advertising and seeks to present a rational approach toward the regulation of advertising.

• Journal of the Korea Concrete Institute
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• v.19 no.6
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• pp.667-676
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• 2007

As the 21st century began, cement and concrete that are representatives of modem building materials became a major factor in global warming, air pollution and environmental pollution. Also, the problems that are generated while pursuing high performance and high strength became social issues. Therefore, it has become urgent to prepare counter plans. This study has aimed at the recycling of sewage sludge ash and developing it as a new concept in building material which serves the environmental considerations for long-lasting developmental purpose. Also, the study aimed to find a substitute for scarce natural resources and to secure high techniques for waste recycling. The purpose of this study was also to solve fundamentally secondary environmental pollution. The results revealed that the chemical components of sewage sludge ash are mainly $SiO_2\;and\;Al_2O_3$ which are similar to the components of pozzolan. Also, it was identified that sewage sludge ash can be utilized as a hardened specimen with an alkali activated pozzolan reaction. Considering the possibility of appropriate strength development and the advantage of drying shrinkage, compared with that of cement, it was believed that sewage sludge ash can demonstrate a function as a substitute for cement given.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1126-1126
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• 2001

The paper presented here is the initial part of a larger study, in which it was determined which quality parameters in cheese powder could already be predicted by NIR at an early stage in the process and which could only be predicted at the final stages of the process. This initial study was performed in order to establish the levels and nature of variation within and between batches such that the subsequent data collection could be tackled optimally. The perspectives evolved into more than was originally planned and revealed some interesting uses of NIR-technology. Cheese powder production starts as a batch process, where waste cheese from other dairies is melted down in a vat. The process then turns into a continual process as the vat is emptied and the melted cheese is then filtered, homogenized, pasteurized and finally spray dried. Between each batch the powder is to a greater or lesser degree a mixture of 2 batches. This paper is divided into 2 aspects, one regarding the optimization of sampling time and the other is a study of process dynamics. Optimizing sampling time This initial study included 9 powder samples from 9 different batches produced during one day. The raw materials for the batches were chosen with the aim of creating a relatively high level of variation in the data. The total of 81 samples were taken out at regular intervals and spectra were collected on a NIR-systems 6500 instrument. The subsequent reduction of the data by PCA to score values shows the power of NIR as a tool to determine not only when samples are representative of a certain batch, but also which batches are stable enough to include in a further study. Studying process dynamics To take this experiment a step further 1 of the 81 samples were sent to the laboratory for further analyses. The samples were chosen on the criteria that they covered the spectral variation in the dataset. These samples were analysed for 4 chemical components and 5 physical attributes, which are essential for describing the quality of the product. The latent structure of the 7 samples, using the chemical and physical variables, is totally comparable to the latent structure of the NIR spectra. This outcome makes it possible to describe the dynamics of one day's production both chemically and physically with relatively little resources. Additionally it raises the question as to whether reference values are needed, as the latent structure of the NIR-spectra appears to be sufficient in providing information on the quality of the product. To be able to use NIR in this way would require defining quality limits in the principal component space as opposed to each of the reference values. The potential of NIR applied in an explorative fashion with batch processes opens a whole new gateway for the use of this technology. This study explains yet again after so many years in the field “why I'm crazy about NIR!”.

• The KIPS Transactions:PartA
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• v.13A no.1 s.98
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• pp.27-34
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• 2006

Designers should know CAD tool/license information such as available number of licenses or tools, types, and configuration methods to use CAD tools properly in their group. Usually, this information is provided by managers who administrate CAD tool and license servers in the specific design group. In the previous CAD tool/licenses sharing methods, designers have to get CAD tool/license information manually and setup the environments with their own hands. n a new designer comes into the design working group, the designer wastes unnecessary design time, because of these processes. As a result, designer's poductivity and utilization of CAD tools will decrease Besides, managers also waste their time and effort, since they should provide CAD tool/license information manually to each designer. In this paper, we present an automated scheme to share CAD tool/license information based on directory service. The proposed methods automate the communication processes between managers and designers that minimze unnecessary time to share CAD information. In addition, as this system maintains the consistency of CAD information automatically that remove the repeated work of managers and designers, it improves the enciency of sharing. Besides, it automates the license configuration steps using prof(y Last, we offer Executable Proxy which is proper for thin CAD application. We believe this scheme will reduce designers and managers' time and effort as well as maximize the utilization of CAD tools.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.467-474
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• 2012

This study was carried out to evaluate effect of temperature condition on nitrogen mineralization of organic matter, distribution of microbial group by PLFA profiles, and soil microbial community structure in volcanic ash soil. Dried soil 30 g mixed well each 2 g of pellet (OFPE) organic fertilizers, pig manure compost (PMC), and food waste compost (FWC). And then had incubated at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, respectively. Nitrogen mineralization rate increased with increasing temperature and that was in the order of FWC>OFPE>PMC. Distribution ratio of microbial group by PLFA profiles were different significantly caused by incubation temperature and the type of organic matter. As incubating time passed, density of microbial group decreased gradually. The Gram-bacteria PLFA/Gram+ bacteria PLFA, Fungi PLFA/Bacteria PLFA, and Unsaturated PLFA/saturated PLFA ratios were decreased according to the increasing temperature gradually. But cy19:0/$18:1{\omega}7c$ ratio increased both FWC and PMC treatment. Principal component analysis using PLFA profiles showed that microbial community structure made up clearly at both 75 days ($10^{\circ}C$) and 270 days ($30^{\circ}C$) by temperature factor. As incubating time passed, microbial community structure shifted gradually.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.293-301
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• 2013

This study discusses the feasibility of coffee bean residue as a raw material of medium-density fiberboard (MDF). In this relation, the effect of coffee bean residue known as an absorbent material on the physical and mechanical properties of MDF manufactured at its different addition level. Coffee bean residue which is a by-product of coffee mill and large amount of waste left over after processing for instant coffee was added at the level of 3, 6, and 9% on dry basis and urea formaldehyde resin was used as the adhesive. The MDF made with mixture of wood fiber and coffee bean residue was tested for physical and mechanical properties as well as formaldehyde emission. The bending strength and internal bonding strength of the MDF made with mixture of wood fiber-coffee bean residue were higher than that of the KS standard in randomized mat structure type, but not in layered mat structure type. Also, the physical properties of MDF made with mixture of wood fiber-coffee bean residue showed a considerable improvement in thickness swelling over the commercial MDF. More importantly, the formaldehyde emission rate of MDF made with mixture of wood fiber-coffee bean residue met the KS standard and was close to that of commercial MDF. These results showed the feasibility of coffee bean residue as a raw material for the production of environmentally-friendly MDF. Additional works on adhesive-coffee bean compatibility, improvement of moisture absorption effect and reduction the formaldehyde emission rate by carbonization of coffee bean residue may be required.

• The Journal of Engineering Geology
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• v.18 no.1
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• pp.55-68
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• 2008

At present underground structures such as road tunnels, railway tunnels, underground petroleum storages and radioactive waste storages are being constructed in numerous places in Korea. For the construction of underground structrues, it should be accounted for natural factors (geology, hydrogeology, soil, vegetation, topography and drainage patterns) and human-social factors (land use, urbanization, population, culture and transportation). Especially, hydrogeology should be regarded as an important factor for evaluating the safety of underground structures and their impact to groundwater system around the structures. This study aimed to recognize hydrogeological characteristics of shallow formations in the area from Dongrae crossway to Seo-Dong where 45 boreholes were drilled for the construction of Line-3 subway in Busan Megacity. Slug tests for unsaturated and saturated zones were conducted on 30 boreholes in the study area. From the result of the slug tests, it was identified that average zonal hydraulic conductivity in the unsaturated zone was higher than that in the saturated zone. Besides, the slug test result in the saturated zones may reflect hydraulic properties of the upper most part of the saturated zones.

• Proceedings of the Korean Society of Grassland Science Conference
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• 2002.09b
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• pp.131-156
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• 2002

Although economically viable, the livestock industry is currently facing a number of challenging environmental problems and highly complex social issues, many of which are related to its size and geographically concentrated nature. Increased emphasis on environmental quality has also placed new demands on livestock producers to ensure that their production practices are in harmony with natural environment. In terms of sustainable agricultural systems, ruminants have served and will continue to serve a valuable role. They are particularly useful in converting vast renewable resources from rangeland, pasture, and crop residues or other by-product into food edible for human. With ruminants, land that is too poor or too erodable to cultivate becomes productive. Also, nutrients in by-products are utilized and do not become a waste-disposal problem. In Korea, however, native and dairy cattle production is not consistent with the advantageous roles of ruminant livestock in sustainable agricultural system because imported feed grains become the main basis for cattle raising. At present the ruminant livestock producers are heavily concentrated in and around the urban areas. About 75% of all the nation's cattle herds are kept on the outskirts of urban areas. As a result, the amount of pasture and forage land available per head of cattle is generally small. Furthermore, animals are raised in a cattle shed with high density. This situation is rather unfavorable for the national economic and environmental points of view As nation income increased, the demand for livestock products grew at an unforeseeable pace. But the pasture area involving in current utilization is tended to decrease during recent years. Based on the above figures more than 250,000 ha of pasture ought to be available for the present herd of cattle. It is obvious that these needs can scarcely be met with arable lands. Lands area for the establishment of new grassland have to be found in the hills and mountains which have not yet been used for crop framing or livestock. The development of extensive grasslands in the hill and woodland areas is now a declared aim. The starting point of the present work is the lack of knowledge of forage production and utilization in hill pasture and woodland in spite of indispensable necessity for livestock production in Korea. The importance of pastoral system in hill region and woodland is particularly emphasized in a standpoint of sustainable livestock production. Main chapter comprises the principle and techniques applicable for improving the utilization of hill pasture and woodland. We finally discussed the problems to solve and future works for a successful livestock production in hill and mountainous area in Korea.