• Journal of Korean Institute of Industrial Engineers
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• v.14 no.1
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• pp.91-101
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• 1988

Break-even analysis is a simple and useful tool in decisions and planning activities though its use is somewhat limited to short-term analysis. The subject is discussed in the fields of engineering economics, production management, cost and managerial accounting, finance, marketing, and so on. Conventional break-even analysis suits the case of stable price and low interest rate. In this paper, we try to overcome the limit by considering following factors, namely, time value of money, depreciation, tax, and capital gains. Also, considering learning effect, we increase applicability to a new project which raises certain changes such as a replacement of production process, an employee turnover, etc. Thus, we suggest a model which has a dynamic break-even quantity per period for the project. Furthermore, we examine the effect of inflation in break-even analysis.

• Environmental and Resource Economics Review
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• v.11 no.3
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• pp.493-513
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• 2002

This empirical study analyzed the policy effect of deregulation in oil product prices. To investigate the effect of deregulation, it is tested whether gasoline prices are determined by market power. Also, the role of government in gasoline tax system is investigated. The empirical analysis has been done by using error correction model. The major findings are as follows. First of all, no significant empirical evidence is found to support that the deregulation affects the determination of gasoline prices. Secondly, the short-term CIF elasticity is estimated to be 0.14. This finding implies that if CIF increases 10%, the gasoline prices increase 1.4%. Finally, the investigation on government role in deregulated market shows that the government has still exercise the power of control through the tax system. For example, the government is seemed to increase the gasoline price more than the increase amount caused by the international oil prices and the exchange rates, because of the intention to achieve the internal revenue increases and lead to gasoline conservation.

• Journal of Labour Economics
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• v.35 no.3
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• pp.29-50
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• 2012

This paper estimates the effect of minimum wages on new hiring of low wage workers from a time-series. The results indicate that minimum wages tend to reduce the new hiring of low wage workers, in particular, among women, less educated and older population. The strongly negative effect on new hiring suggests that the burden of reduced labor demand arising from higher minimum wages tend to fall mostly upon the unprotected low-wage job searchers due to the short-term rigidity of employment adjustment among the existing workers.

• Journal of the military operations research society of Korea
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• v.10 no.2
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• pp.51-59
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• 1984

Military personnel encounter a variety of noise environments. During exercises, high intensity noise levels are often encountered. Twenty-four subjects were required to respond to symbols presented under two levels of task difficulty, two levels of presentation rate, two levels of display orientation, and three levels of noise intensity. The purpose of the experiment was to determine whether noise intensity and display orientation had any effect on a short-term memory task. Results showed that continuous white noise at intensity levels of 30, 85, and 105 db had no effect on the shortterm memory task. Presentation rate and task difficulty demonstrated a significant relationship with task performance as did their two-way interaction. This two-way interaction between presentation rate and task difficulty exhibited a different pattern for the two levels of display orientation.

• Journal of Nutrition and Health
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• v.22 no.6
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• pp.497-506
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• 1989

To investigate the effect of levels of dietary protein and age on bone metabolism 40% and 5% casein were fed to the rats of 2 & 13 months of age for 12 weeks. High protein groups showed higher bone weight and Ca content than low protein groups and urinary Ca loss was increased in high protein groups but the difference disappeared gradually. A significant increase in urinary hydroxyproline excretion was noted in high protein groups of both age. Another short term study was undertaken to study if the above effect was related with renal function or PTH. Extremely high and low protein diets(60%, 6%) were fed to the rats of different ages(6wks, 6mos.) for 2 weeks, Urinary Ca excretion was significantly increased in high protein groups of young and aged rats and GFR was increased as well. There was no difference in serum iPTH levels between low and high protein groups, but it was elevated in aged rats. Alkaline phosphatase activity was higher in young rats, reflecting faster bone formation. The observed hypercalciuria in high protein groups, especially in aged rats, seems to be related to higher GFR, and PTH dose not appear to be a major mediator.

• Journal of Environmental Science International
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• v.33 no.4
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• pp.249-256
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• 2024

This study aimed to verify the healing effect through brain and pulse wave analyses before and after a forest walk to the university students. Bio-signals of brain and pulse waves were measured using Omnifit Mindcare. After analyzing four brain wave items such as concentration and four pulse wave items such as heart health, it is identified that the stress level of university students was higher than that of the general public, and the brain stress level was approached to the normal range for 19 people with clear improvement. For pulse waves, a statistically significant decrease in sympathetic nerve activity (%) was confirmed. Although the slight fluctuations within the normal range were caused by short term and individual differences, it showed that the forest walking is partially effect on the relieving stress.

• Radiation Oncology Journal
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• v.35 no.3
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• pp.189-197
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• 2017

Locally advanced prostate cancer (LAPC) is defined as histologically proven T3-4 prostatic adenocarcinoma. In this review, we define the individual roles of radiotherapy (RT), short-term (ST-) and long-term (LT-) androgen deprivation therapy (ADT), and their combination in multimodal therapy for LAPC. Despite limitations in comparing the clinical outcomes among published papers, in the present study, a trend of 10-year clinical outcomes was roughly estimated by calculating the average rates weighted by the cohort number. With RT alone, the following rates were estimated: 87% biochemical failure, 34% local failure (LF), 48% distant metastasis (DM), 38% overall survival (OS), and 27% disease-specific mortality (DSM). Those associated with ADT alone were 74% BCF, 54% OS, and 25% DSM, which appeared to be better than those of RT alone. The addition of ADT to RT produced a notable local and systemic effect, regardless of ST- or LT-ADT. The LF rate decreased from 34% with RT alone to 21% with ST-ADT and further to 15% with LT-ADT. The DM and DSM rates also showed a similar trend among RT alone, RT+ST-ADT, and RT+LT-ADT. The combination of RT+LT-ADT resulted in the best long-term clinical outcomes, indicating that both RT and ADT are important parts of multimodal therapy.

• Korean Journal of Clinical Pharmacy
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• v.2 no.1
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• pp.11-22
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• 1992

Thymic extract showed antitumor effect to sarcoma mice with higher dose$(200{\mu}g/mouse/day$ i.p., 4weeks) but not with low dose$(5{\mu}g/mouse/day$ i.p., 6 weeks). Direct cytotoxicities were exhibited against sarcoma 180, L1210 and MOLT-4 by MTT assay. The spleen weight of mice were increased but the number of circulating lymphocytes were not increased after long-term(2 weeks) administration of thymic extract. Evaluating the mitogenesis by MTT assay. $\%$ absorbance of human lymphocytes was not increased by thymic extract. Cell cycle statistics of S phase and $G_2/M$ phase was not increased in the presence of that by PI staining. The formation of rosette was induced, irrespectively of exposure time short-term(l hour) and long-term(2 weeks). The population of mouse blood T-cell to bind Lyt2-antimonoclonal antibody and to $L_2T_4$ were increased after administration of thymic extract$(2-200{\mu}g/mouse/day)$. From the above results, it is suggested that thymic extract exerts antitumor activity by stimulating T cells to differeniate in vivo but not in vitro.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.545-548
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• 2006

This study has been carried out to examine the properties of concrete according to replacement ratio and curing method of fly ash, in order to increase utilization of it. As the result of experiments, the 7 days of early age strength presented around 20MPa, up to 20% of replacement ratio, which is almost the same strength as non-replacement. However, when the replacement ratio was 30%, the strength was decreased to 16MPa, as 20% reduction compared to the non-replacement condition. In 365 days of long term aging, the strength was 5% higher, up to 20% of the replacement ratio, due to the pozzolanic reaction of fly ash. When the replacement ratio was 30%, it presented similar strength development as the non-replacement condition. Steam curing and autoclave curing increased the short age strength, regardless of the replacement ratio of fly ash; however, they don't have an effect on increasing the 365 days of long term strength. Water curing showed high strength development after 28 days, 51.81MPa, which is around 30% higher than air curing, 38.9MPa, steam curing, 38.6MPa, and autoclave curing, 39MPa. Therefore, water curing was examined as one of the very effective curing methods for developing long term strength of concrete.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.137-144
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• 2005

Recently a pressurized grouting soil nail is demanded due to problems beyond of economical and engineering purpose. In this study, a newly modified soil nailing technology named as the PGSN (Pressurized Grouting Soil Nailing) system is respected to reduced displacements of nails and increase of global slope stability. And effects of various factors related to the design of the PGSN system, such as the length of the soil nail, injected pressure and W/C ratio of cement grout in the pressurized grouting soil nail are examined throughout a series of the displacement-controlled field pull-out tests. Displacement-controlled field pull-out tests are performed in the present study and the volume of grouting are also evaluated based on the measurements. In addition, both short-term and long-term characteristics of pull-out deformations of the newly proposed PGSN system are analyzed and compared with those of the general soil nailing system by carrying out the stress-controlled field pull-out tests. From the pull-out characteristics of pressurized grouting soil nails, it is found that the effect of the length of the soil nail, injected pressure and W/C ratio of cement grout are important parameters.