• Journal of Korean Port Research
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• v.10 no.2
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• pp.91-101
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• 1996

Today transportation problems are severer with the increase of the vehicles and travel demand in urban areas, but could not be completely solved with only the expansion of the new transportation facilities. Because the expansion of the new transportation facilities are limited in urban areas. As one of the Transportation System Management(TSM) techniques in this study, the simulation results of the existing signal systems which were operated based upon the peak time periods for increasing the efficiency on the pretimed signalized intersections(PSI) during the different time periods : the AM on-Peak, the AM off-Peak, the PM off-Peak, and the PM on-Peak, were as follows : i) There was no distinct difference in the total traffic volumes concentrated on the signalized intersections during the different time periods, but a considerably big difference in the directional traffic volumes for those time periods. ii) There were about 53% reduction of the average delay and 51% reduction of the fuel consumption when applying the different signal systems to the different time periods regardless of the CBD and Non-CBD. iii) There were about 36% increase of the average delay and 33% increase of the fuel consumption when applying the same signal systems during the peak time periods to the different time periods regardless of the CBD and Non-CBD. Based on the above results, it was concluded that constructing the different signal systems for the different time periods would be better than construction the same ones for those periods on the pretimed signalized intersections in urban areas.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3D
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• pp.399-408
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• 2009

The major changes in construction environment are that construction project is bigger and more complicated and the power of construction market changes from the supplier to the client or the user. Especially public construction enterprises have advanced to introduce the value engineering (VE) which is one of the cost management based on the owner's leading at the design phase for economical efficiency and quality improvement. According to the these efforts, the implementation of VE was legislated in the revised Construction Technology Management Act in 2000, governmental agencies, local autonomies, and construction public enterprises universally has taken the VE into consideration. In this circumstance, the scope that VE construction applied at 50 billion won projects from 2003 has been extended to 10 billion won projects in 2006. Therefore, the VE construction will be activated in the future. The cost savings and function improvement, which are the purpose of VE are not only construction public enterprises, but also every public client supported from government's budget or owned by the government. Therefore, the purpose of this study is to propose the improved process and performance index of VE for governmental agencies, local autonomies, and construction public enterprises which want to introduce or improve the VE process. This research also suggested the To-be design-phased VE process model. In addition, it suggested the To-be model of design management reflected the To-be design-phased VE process model, which is eliminated two problems reflected for the performance improvement of the As-is model of design management.

• Asia Marketing Journal
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• v.15 no.3
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• pp.79-95
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• 2013

New product innovation is a process of embodying new knowledge in a product and technology licensing is getting popular as a means to innovations and introduction of new product to the market in today's competitive global market environment. Incumbents often rely on technology licensing to access new product opportunities created by other firms. Prior research has examined various aspects of technology licensing agreements such as specific contract terms of licensing agreements, e.g., distribution of control rights, exclusivity of licensing agreements, cross-licensing, and the scope of licensing agreements. This study aims to provide answers to an important, but under-researched question: why do some incumbents initiate more licensing agreement for exploratory learning while others do it for exploitative learning along the innovation process? We attempt to extend our knowledge of licensing agreements from an organizational learning perspective. Technology licensing as a specific form of interfirm linkages can be initiated with different learning objectives along the process of new product innovation. The exploratory stages of the innovation process such as discovery or research stages involve extensive searches to create new knowledge or capabilities, whereas the exploitative stages of the innovation process such as application or test stages near the commercialization are more focused on developing specific applications or improving their efficiency or reliability. Thus, different stages of the innovation process generate different types of learning and the resulting technological resources. We examine when incumbents as licensees initiate more licensing agreements for exploratory learning objectives and when more for exploitative learning objectives, focusing on two factors that may influence a firm's formation of exploratory and exploitative licensing agreements: 1) its past radical and incremental innovation experience and 2) its internal investments in R&D and marketing. We develop and test our hypotheses regarding the relationship between a firm's radical and incremental new product experience, R&D investment intensity and marketing investment intensity, and the likelihood of engaging in exploratory and exploitive licensing agreements. Using data collected from various secondary sources (Recap database, Compustat database, and FDA website), we analyzed technology licensing agreements initiated in the biotechnology and pharmaceutical industries from 1988 to 2011. The results of this study show that incumbents initiate exploratory rather than exploitative licensing agreements when they have more radical innovation experience and when they invest in R&D activities more intensively; in contrast, they initiate exploitative rather than exploratory licensing agreements when they have more incremental innovation experience and when they invest in marketing activities more intensively. The findings of this study contribute to the licensing and interfirm cooperation studies. First, this study lays a foundation to understand the organizational learning aspect of technology licensing agreements. Second, this study sheds lights on how a firm's internal investments in R&D and marketing are linked to its tendency to initiate licensing agreements along the innovation process. Finally, the findings of this study provide important insight to managers regarding which technologies to gain via licensing agreements. This study suggests that firms need to consider their internal investments in R&D and marketing as well as their past innovation experiences when they initiate licensing agreements along the process of new product innovation.

• Journal of Radiation Industry
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• v.18 no.3
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• pp.167-171
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• 2024

Technetium-99 (⁹⁹Tc) is recognized as a critical concern in the disposal of spent nuclear fuel due to its long half-life and remarkable stability, existing predominantly as TcO₄^- in the natural environment. The anionic form of technetium is highly soluble and mobile, posing significant environmental risks from the viewpoint of nuclear waste management. Thus, developing efficient and cost-effective sorbents for aqueous Tc(VII) is essential for mitigating relevant contamination. In the present work, the adsorption characteristics of Re(VII), a chemical analog of Tc(VII), were investigated using the clay mineral bentonite, modified with two different organic cations: hexadecylpyridinium (HDPy) and hexadecyltrimethylammonium (HDTMA). Sorption experiments were conducted at a liquid-to-solid ratio of 1 g/L with Re(VII) solutions prepared at concentrations from 10^-4 mol/L to 10^-6 mol/L. The sorption ratio and distribution coefficients were determined with samples collected at reaction times of 10, 50, 100, and 500 minutes after 0.45 ㎛ syringe filtration. In parallel, the modified bentonite samples were further analyzed using the X-ray diffraction (XRD) method to understand the adsorption mechanism of Re(VII) onto the target minerals. According to the quantification analysis results, a rapid equilibrium reaction of aqueous Re(VII) for all modified bentonite samples was identified. Moreover, near-complete adsorption of Re(VII) was observed when the bentonite was modified at 200-400% of its cation exchange capacity (CEC) for both organic cations. For cases of lower modification, the HDTMA-modified bentonite showed relatively higher adsorption efficiency compared with the one modified with HDPy. This result was inferred to be due to the difference in inter-layer spacing based on the characteristics of the organic cations. It is expected that the results obtained through this study will serve as a preliminary case for the synthesis of adsorbents for the retardation of highly mobile anionic radionuclides, such as I and Tc, in the natural environment.

• Economic and Environmental Geology
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• v.55 no.4
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• pp.377-388
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• 2022

Laboratory-scale experiments were performed to identify the As removal mechanism of the residual slag generated after the mineral carbonation process. The residual slags were manufactured from the steelmaking slag (blast oxygen furnace slag: BOF) through direct and indirect carbonation process. RDBOF (residual BOF after the direct carbonation) and RIBOF (residual BOF after the indirect carbonation) showed different physicochemical-structural characteristics compared with raw BOF such as chemical-mineralogical properties, the pH level of leachate and forming micropores on the surface of the slag. In batch experiment, 0.1 g of residual slag was added to 10 mL of As-solution (initial concentration: 203.6 mg/L) titrated at various pH levels. The RDBOF showed 99.3% of As removal efficiency at initial pH 1, while it sharply decreased with the increase of initial pH. As the initial pH of solution decreased, the dissolution of carbonate minerals covering the surface was accelerated, increasing the exposed area of Fe-oxide and promoting the adsorption of As-oxyanions on the RDBOF surface. Whereas, the As removal efficiency of RIBOF increased with the increase of initial pH levels, and it reached up to 70% at initial pH 10. Considering the PZC (point of zero charge) of the RIBOF (pH 4.5), it was hardly expected that the electrical adsorption of As-oxyanion on surface of the RIBOF at initial pH of 4-10. Nevertheless it was observed that As-oxyanion was linked to the Fe-oxide on the RIBOF surface by the cation bridge effect of divalent cations such as Ca²⁺, Mn²⁺, and Fe²⁺. The surface of RIBOF became stronger negatively charged, the cation bridge effect was more strictly enforced, and more As can be fixed on the RIBOF surface. However, the Ca-products start to precipitate on the surface at pH 10-11 or higher and they even prevent the surface adsorption of As-oxyanion by Fe-oxide. The TCLP test was performed to evaluate the stability of As fixed on the surface of the residual slag after the batch experiment. Results supported that RDBOF and RIBOF firmly fixed As over the wide pH levels, by considering their As desorption rate of less than 2%. From the results of this study, it was proved that both residual slags can be used as an eco-friendly and low-cost As remover with high As removal efficiency and high stability and they also overcome the pH increase in solution, which is the disadvantage of existing steelmaking slag as an As remover.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.157-166
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• 1995

The fate and use efficiency of applied nitrogen were evaluated in a pot experiment with different fertilizers and water management practices during 30days after fertilizer application. N-P-K compound fertilizers, 13-10-1l(F-l) for upland Crop use and 15-10-10(F-3) for rice Crop use, and mixed fertilizer, 21-17-17(F-2) for basal dressing in rice were used. Fertilizers corresponding to 1.8g N were mixed thoroughly with the whole volume of sandy loam soil in a pot. The pots were flooded upto 3cm above soil surface for O(0dF), 10(10dF), 20(20dF), and 30(30dF) days after fertilizer application and all the treatments were flooded continuously from 30 days after fertilizer application. During the flooding period water percolation rate was adjusted to 2.5mm/day. Rice seedlings were transplanted 40 days after fertilizer application. The pH of infiltrated water increased with increasing duration of flooding. The pH of F-2 was higher than those of F-1 and F-3 between which there were no differences. The applied nitrogen remained 23% in F-1, 29% in F-2, and 29.1 % in F-3, and 45.0% in 0dF, 26.6% in 10dF, 24.8% in 20dF, and 20.3% in 30dF as inorganic nitrogen at 63 days after fertilizer application. Nitrogen losses by leaching amounted to 51.3%, 32.1% and 48.1% of applied nitrogen in F-1, F-2 and F-3, respectively. Nitrogen leaching losses increased with increasing duration of flood- ing, amounting to 25.7%, 29.8%, 32.7%, and 35.8% in 0dF, 10dF, 20dF and 30dF, respectively. Gaseous loss of applied nitrogen was greatest in F-2, followed by F-1 and F-3. Total loss of nitrogen due to gaseous volatilization and leaching was greatest in F -1, followed by F -2 and F-3, and were greater in the treatments with longer flooding after fertilizer application. Nitrogen recovery by rice shoot until 72 days after transplanting were 23.2%, 24.7% and 27.4% of applied nitrogen in F-1, F-2 and F-3, respectively and 34.1%, 25.5%, 21.1%, and 21.2% in 0dF, 10dF, 20dF and 30dF, respectively.

• Journal of Aquaculture
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• v.18 no.4
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• pp.225-230
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• 2005

This experiment was conducted to compare the effects of extruded pellets and raw fish-based pellet on olive flounder Paralichthys. olivaceus. Six diets were prepared for this study: two formulated extruded pellets (FEP1 & FEP2), three commercially available extruded pellets (CEP1, CEP2 & CEP3) and moist pellet (MP). Weight gain offish fed FEP1 and CEP3 were significantly higher (P<0.05) than those of fish fed FEP2, CEP1, CEP2 and MP, while that of fish fed MP was not significantly different (f<0.05) from those of fish fed the FEP2, CEP1 and CEP2. Feed efficiency of fish fed CEP2 was significantly lower (P<0.05) than those of fish fed FEP1, FEP2, CEP1, CEP3 and MP. There was no significant difference in protein efficiency ratio and hepatosomatic index between fish fed FEP1 and CEP3, and among fish fed FEP2, CEP1 and CEP2. There was no significant difference in condition factor among fish fed the FEP1 and CEP3, and between fish fed FEP2, CTP1 and MP. However, fish fed MP had a lower survival rate than fish fed the other five EP These results suggest that diet FEPl could be developed to replace MP for the owing stage of flounder without adverse effects on growth performance.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.404-408
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• 2005

In order to obtain the basic information far agricultural utilization of Germanium (Ge), the growth characteristics and germanium absorption in lettuce were investigated with different concentration of germanium in soil. This experiment was carried out in the waster pot $(15,000^{-1}a)$. Germanium concentrations in soil for lettuce cultivation were maintained at 0.26, 2.0, 4.0, 6.0 and $8.0mg\;kg^{-1}$, respectively. The content of germanium in lettuce was increased with the increase of germanium concentration in soil. When lettuce was cultivated on soil supplemented with Ge $8.0mg\;kg^{-1}$, germanium phytotoxicity (reduction of plant height, No. of leaf and fresh weight) was not observed. When lettuce was cultivated on soil supplemented with Ge 4.0 and $8.0mg\;kg^{-1}$, it germanium content were found 0.75 and $1.27mg\;kg^{-1}$, respectively. Germanium absorption efficiency of lettuce was not different by germanium concentrations in the soil. When lettuce was cultivated on soil supplemented with Ge 2.0, 4.0 and $8.0mg\;kg^{-1}$, its absorption germanium efficiency was found 0.05, 0.04 and 0.03%, respectively. Germanium contents in different parts of lettuce cultivated with Ge $8.0mg\;kg^{-1}$ were $0.65mg\;kg^{-1}$ on inner leaf and $1.59mg\;kg^{-1}$ on outer leaf.

• Korean Journal of Poultry Science
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• v.36 no.4
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• pp.287-292
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• 2009

The objective of the current study was to evaluate the effects of garlic extract (GE) supplementation on growth performance, nutrient digestibility, carcass characteristics and meat composition in broilers. Dietary treatment were control (corn-soy based diet, 0 ppm), and diets added with 100 or 200 ppm GE. Starter and finisher diets were fed from 0 to 3 wk and 4 to 5 wk, respectively. Supplementation of GE had no effect on weight gain, but there was trend towards improvement in growth rate in birds fed diets containing 100 ppm GE during overall period, while birds fed 100 ppm GE had better feed efficiency (p<0.05) than birds fed control diet during finisher period. Birds fed GE had greater (p<0.05) nutrient digestibility of dry matter than birds fed control diet. The TBARS values of breast muscle obtained from birds fed 100 and 200 ppm GE were lower than breast muscle of control birds on day 8 and 12 of storage. The breast muscle of birds fed 200 ppm GE had higher (p<0.05) $L^*$ values than breast muscle of birds fed control and 100 ppm GE diets. The carcass characteristics, meat and bone composition, CIE $a^*$ and $b^*$ values did not differ among the dietary treatments. In conclusion, supplementation of GE enhanced feed efficiency and nutrient digestibility in broilers.

• Korean Journal of Poultry Science
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• v.6 no.2
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• pp.83-90
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• 1979

In order to evaluate the effect of lipids on the utilization of the energy and Protein of the diet, the isocaloric and isoprotein diets added with mutton fat, tallow, and lecithin at the levels of two percent and five percent were prepared. The growth of chicken and the feed efficiency were observed on hatched chicken which were fed a commercial diet for the first week, with starters for the next four weeks, and with finisher diets for the last three weeks respectively during the eight weeks of the experiment. Growth rate, feed efficiency, and average body weight gain per day were similar among the chicken fed diets containing various lipids or at the levels of two percent and five percent. The metabolizable energy of the diets was found to be from 2.713kcal to 3.059kcal per gram, and the metabolizability of the gross energy was from 62 percent to 70 percent. Also the metabolizability of basal diet was higher as compared with the diets containing lipids. And the lower energy utilization was found in the broilers fed diets containing five percent lipids than those of two percent, showing not significant difference between them. Daily metabolizable energy of three week old birds ranged from 132kca1 to 168kcal which resulted in also a tendency of lower values in the five percent diets. And daily retained nitrogen of birds ranged from 0.631 gr to 0.738 gr, which showed an increasing tendency on the birds fed five percent mutton fat and tallow in comparison with those of two percent. But the lecithin brought about a reverse tendency. The digestibility of crude fats was found to be from 48 percent to 76 percent, but not significant difference among diets plus lipids or at the levels of two percent and five percent. The birds fed five percent mutton fat and tallow showed a tendency of lower digestibility as. compared with those fed two percent, but the similar results were found between two percent and five percent lecithin fed to the birds. Then, it was tentatively concluded that the effect of the mutton fat on the energy and protein utilization was similar to tallow but resulted different tendency with lecithin.