• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.496-501
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• 2012

Thirty-five available feeds were fermented in vitro in order to investigate their soluble total organic carbon (TOCs) and methane ($CH_4$) production rate. A fermentation reactor was designed to capture the $CH_4$ gas emitted and to collect liquor from the reactor during in vitro fermentation. The results showed that $CH_4$ production rate greatly varied among feeds with different ingredients. The lowest $CH_4$-producing feeds were corn gluten feed, brewer's grain, and orchard grass among the energy, protein, and forage feed groups, respectively. Significant differences (p<0.05) were found in digestibility, soluble total organic carbon (TOCs), and $CH_4$ emissions among feeds, during 48 h of in vitro fermentation. Digestibility and TOCs was not found to be related due to different fermentation pattern of each but TOCs production was directly proportional to $CH_4$ production (y = 0.0076x, $r^2$ = 0.83). From this in vitro study, TOCs production could be used as an indirect index for estimation of $CH_4$ emission from feed ingredients.

• Korean Management Science Review
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• v.31 no.1
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• pp.27-40
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• 2014

Tour products have been recognized as a perishable asset. For tour operation companies (TOCs), improving profitability is a core decision problem for their business. Since package tour products, typical products of TOCs, are perishable after the tour was departed, TOCs have been tried to increase their sales before the departure date with various marketing strategies including price discounts. The pricing problem for perishable assets have been studied in Revenue Management for a long time. However, it is hard to find a research on pricing decisions for tour products. In this paper, we focus on a pricing problem for tour products. In particular, we will consider the pricing scheme with customer preference values on purchasing conditions. With conjoint analysis, we can use the part-worth value as a preference value for each level of purchasing conditions. To construct various discount prices, we use an enumeration method and suggest a mathematical optimization model. With experimental analysis for a sample tour package, we will show that our pricing process is very helpful for designing customer-oriented pricing decision.

• Journal of the Korean Society for information Management
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• v.36 no.2
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• pp.255-273
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• 2019

Recently, the table of contents (TOC) has been becoming increasingly accessible and utilized. The study conducted descriptive statistics and comparative analysis of the table of contents in terms of parts of speech and subject in text. For this purpose, this study chose the books of the social sciences field from acquisition lists of an academic library, obtained Dewey class numbers of target books from KERIS union catalog, and extracted TOC data from online bookstore. Morphological analysis was performed on each book titles and TOCs, and descriptive statistics and frequency analysis were carried out. As a result, nouns made up roughly half of the morphemes of titles or the TOCs. TOCs had about 50 times more nouns than titles. The percentage of unique nouns that appeared only in the table of contents is estimated to be 95.2% of the TOC's total nouns. The table of contents also showed a differences in its lengths depending on the field of social science.

• Journal of Korea Port Economic Association
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• v.35 no.3
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• pp.1-18
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• 2019

The competition between port authorities (PAs) and terminal operating companies (TOCs) in providing port logistics services has gained importance. The PAs enter into leasing contracts with TOCs in various ways. This study aims to model a contract method that maximizes the joint profit between a PA and a TOC. Particularly, this study aims to model the equilibrium by comparing four types of contract schemes in the non-coordination, cooperation, Cournot, and collusion models. The results of the analysis show that the two-part tariff scheme generates a higher joint profit than the fixed and fee contracts. It is understood that risk- and profit-sharing between the PAs and TOCs helps the latter to maximize the throughput and the joint profit. These results are expected to provide an important theoretical basis for decision-making about port rent and freight between the PAs and TOCs.

• Journal of the Korean Society for information Management
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• v.37 no.1
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• pp.1-21
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• 2020

This study applied automatic classification using table of contents (TOC) text for 6,253 social science books from a newly arrived list collected by a university library. The k-nearest neighbors (kNN) algorithm was used as a classifier, and the ten divisions on the second level of the DDC's main class 300 given to books by the library were used as classes (labels). The features used in this study were keywords extracted from titles and TOCs of the books. The TOCs were obtained through the OpenAPI from an Internet bookstore. As a result, it was found that the TOC features were good for improving both classification recall and precision. The TOC was shown to reduce the overfitting problem of imbalanced data with its rich features. Law and education have high topic specificity in the field of social sciences, so the only title features can bring good classification performance in these fields.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.75-80
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• 2009

Composition changes of swine manure and the effects on MAP ($MgNH_4PO_46H_2O$) crystallization by microwave irradiation were examined. The concentration of ${PO_4}^{3-}$ was increased within a fixed period of time and then decreased, but $NH_4$-N was reduced continuously during microwave irradiation. Concentration of ${PO_4}^{3-}$ was started to reduce just from the point of foam formation during microwave irradiation, and the temperature at that time was always $49^{\circ}C$ irrespectively to microwave irradiation rate. Inorganic carbon was reduced with microwave irradiation, but soluble organic carbon (TOCs) was increased proportionally. Crystallization rate under conditions of non-microwave irradiation, irradiation up to $93^{\circ}C$ and $48^{\circ}C$ was 87.8%, 87.3% and 98.5%, respectively, showing 10% enhancement when irradiated up to $48^{\circ}C$. However, removal efficiency of ammonia nitrogen was proportional to the microwave irradiation rate or duration, obtaining 2.5%, 4.5% and 10.2%, respectively. Based on these results, it would be a useful strategy to irradiate microwave up to $49^{\circ}C$ to enhance MAP crystallization rate by changing the ionic pattern of nutrients in the manure. Meanwhile, provision of enough microwave irradiation rate might be needed to achieve high $NH_4$-N removal.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.1
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• pp.84-98
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• 2000

Control of Trihalomethanes(THMs) is a major concern of many water treatment plants. A number of researchers have studied the effectiveness of activated carbon adsorption process in removing THMs or organic halogen compounds. Recently, attention has been paid to the biological activated carbon (BAC) treatment of THM precursors as an alternative to the carbon adsorption treatment because of its effectiveness as well as its low running cost. In this study, changes of THM formation potential(THMFP) and removal of substrates in the SBR effluent were investigated in an attempt to clarify the mechanisms of the decrease/increase of THMFP in the BAC treatment. The increase and decrease of THMFP concentrations were observed in effluents during prolonged operation. When PCP or DBS was feeded as substrate contained in SBR effluent, the THMFPs were easyly removed with TOCs removal. But the case of SBR effluent containing SDS or glycine was introduced, and when microbial growth came to its near steady state, the THMFPs of treated effluents were increased more or less in comparison to those in the influents. Such increases of THMFP coincided with the increase in microbial growth within the activated carbon fiber(ACF) column. In the case of only sucrose was feeded as substrate on ACF colume, THMFP concentrations of effluent were higher than those of influent. The THMFP concentration was significantly increased on inlet part of ACF column, which biomass inhabits abundantly, then they were decreased gradually. These increases mean production of the secondary THM precursors by biological activities, which can be removed by adsorption and biological degradation on ACF column.

• Journal of Korean Library and Information Science Society
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• v.39 no.1
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• pp.299-318
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• 2008

Library catalogs are as a tool in order to satisfy the information needs of user but currently user's need is more complex and more diverse. Therefore, currently library catalogs do not meet the user's need and have some limitations. One of the ways for solving this problem will provide for the table of contents about monography. However recently, table of contents about books is builded individual library itself so the redundancy issue is pointed to waste of the cost of materials and human resources. Therefore, it should establish a standardized table of contents information DB and each of the related institutions can collaborate and share ways to be provided to take advantage of the table of contents. In order to this, central institutions should be provided a standardized way of building DB, provided conversion program, and mutual sharing principles associated with the building of table of contents DB.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.641-648
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• 2003

In a batch mode treatment process, which electrolyzes the wastewater after derivation of N-P crystal formation and recovery, the characteristics of pollutant removal induced with the changes of loading rate and hydraulic retention time were studied. $MgCl_2$ was used as Mg source for the formation of struvite and the molar ratio of $MgCl_2$ to $PO_4^{3-}$ in influent was 1.3. When analyzing the average treatment efficiencies and removal characteristics obtained from four separate operations (Run I, II, III, IV), removal efficiencies of PO43- was not function of its loading rate. Under a condition of sufficient aeration and Mg source provided, over 88% of $PO_4^{3-}$ was eliminated by the formation of MAP without any pH adjustment, in spite of loading rate variation. An optimum-loading rate of NH4-N to achieve high removal efficiency was approximately $100g/m^3/d$. Below that loading rate, the removal of NH4-N was proportional to the loading rate into the system, and hence stable and high removal efficiency, over 90%, was achieved. However, when the loading rate increased over that rate, removal efficiency began to drop and fluctuate. Removal efficiency of TOCs was dependant upon the hydraulic retention time ($r^2$=0.97), not upon the loading rate. Stable and high color removal (94%) was obtained with 2 days of HRT in electrolysis reactor.