• Journal of Electrical Engineering and Technology
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• v.4 no.1
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• pp.123-130
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• 2009

The partial discharge (PD) measurement is a very effective method to assess the winding insulation condition of high-voltage machines, since most of the insulation failure processes are directly or indirectly caused by PD. On-line PD measurements, which can detect insulation defects of winding in the early stages on rotating machines in operation, have been accepted as the most important technique. The epoxy mica capacitive coupler is currently and extensively used for on-line detection of PD pulses of high-voltage rotating machines. To evaluate the feasibility of developing a capacitive coupler that is easier to manufacture at a lower cost compared to epoxy mica couplers, a 100pF capacitive coupler made of ceramic material is designed, fabricated and tested for on-line PD measurements of 23 kV electrical machines. A series of electrical tests and accelerated aging tests are performed on the ceramic coupler to evaluate the performance requirements, long-term reliability and thermal stability for in field application. The test results show that the newly developed ceramic coupler provides equal and improved performance at a lower cost compared to epoxy mica couplers, and estimated voltage life is anticipated to surpass 100 years.

• Journal of the Korea Institute of Building Construction
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• v.6 no.4 s.22
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• pp.85-92
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• 2006

Urethane, epoxy, acrylic have common property to adhere on the concrete dried surface in the waterproofing materials at present. In the wet condition, however, the materials such as urethane, epoxy, acrylic need a long hardening time and it become a reason of water leakage as the materials breaking down. it is one of the problem to adhere to the substrate. Therefore, in this thesis, I focused to assure the structural safety and durability and quality for waterproofing and safe of construction cost by cut down the cost of labor and reduce the term of works as searching the application of field condition for high adhesive spray type of degenerated and rubberized asphalt membrane material.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.2
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• pp.141-145
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• 2008

Due to the uncertainties resulting from cost projection, evaluation over long term period, and adequacy of applied discount rate, the economic assessment for back-end fuel cycle is different from each organizations or individuals. In this paper, the features and limitations of some noticeable economic evaluations were investigated and analysed to contribute for the public participation and back-end fuel cycle policy related researches. As a result of analysis, we found that the reprocess and recycling is more economical than direct disposal option, but the result includes high uncertainty that depends on the input parameters.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.621-639
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• 2022

Cortisol and corticosterone, hormones traditionally considered biomarkers of stress, can be measured in fluid biomatrices (e.g., blood, saliva) from live animals to evaluate conditions at sampling time, or in solid biomatrices (e.g., hair, feather) from live or dead animals to obtain information regarding long-term changes. Using these biomarkers to evaluate physiological stress responses in domestic animals may be challenging due to the diverse characteristics of biomatrices for potential measurement. Ideally, a single measurement from the biomatrix should be sufficient for evaluating chronic stress. The availability of appropriate and cost-effective immunoassay methods for detecting the biomarkers should also be considered. This review discusses the strengths and limitations of different biomatrices with regard to ensuring the highest possible reliability for chronic stress evaluation. Overall, solid biomatrices require less frequent sampling than other biomatrices, resulting in greater time- and cost-effectiveness, greater ease of use, and fewer errors. The multiplex immunoassay can be used to analyze interactions and correlations between cortisol and other stress biomarkers in the same biomatrix. In light of the lack of information regarding appropriate biomatrices for measuring chronic stress, this review may help investigators set experimental conditions or design biological research.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.503-507
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• 2015

Sustainability continues to gain traction in all industry sectors as people become aware of the advantages of green products. The voluntary use of green products in buildings in the United States continues to grow due to long-term cost saving and the ecological benefit to nature. The voluntary installation of green products is associated with end-users' expectations and perceptions including cost saving, sustainable behavior, and social responsibility. Although involuntary use of green products has similar expectations and perceptions, the installation decision is not based on the goodwill from end-users. This paper surveys college students to capture current experience levels, expectations, and perceptions in regard to green products and/or sustainability and to understand their attitudes about involuntary use of a green product. The installation of low water pressure showerheads in a dormitory provides data to support perception, expectation, and future direction of adoption of green products in public buildings. This information may be used to facilitate sustainable behaviors among involuntary groups regarding to the adoption of green products. The primary objective of this paper is to investigate the college students' perception of a green product, particularly when the students are involuntarily exposed to the green products. As a secondary objective, the paper also attempts to address the college students' general understanding on sustainability and green products. The findings of this study could support the growing importance of sustainable behavior among higher education beyond social responsibility and provide a benchmark against which to improve future change while fostering sustainable behaviors over time among the public.

• Korea Trade Review
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• v.47 no.1
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• pp.13-24
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• 2022

This study was conducted because the global economic downturn caused by COVID-19 caused a surge in logistics costs and it was no longer possible to predict logistics costs using existing methods. For this study, we made the assumption that economic indicators affect logistics cost. Chapter 2 examines the current status of the liner market and factors affecting logistics costs. Based on this, Chapter 3 collects independent and dependent variables to determine the analysis model. As the independent variable, economic indicators of major countries constituting the SCFI were selected, and the dependent variables were the SCFI Europe Index and the SCFI USA Index. In Chapter 4, a panel analysis was conducted based on this, and it was confirmed that major economic indicators had a negative (-) effect on SCFI. This is contrary to the existing research results, which can be attributed to the special situation caused by COVID-19 and the imbalance of demand and supply by region. The results of this study are meaningful in that they can predict long-term logistics cost volatility without analyzing supply and demand, and can be applied to other studies as well.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.5
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• pp.443-450
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• 2013

We consider user pairing and resource allocation for the uplink of cellular systems employing virtual multiple input multiple output (MIMO). As a multiple access scheme, discrete Fourier transform spread orthogonal frequency division multiple access (DFTS-OFDMA) is adopted for more flexible resource allocation than single carrier (SC)-OFDMA adopted in the Long Term Evolution (LTE) system. We formulate the optimization problems of user pairing and resource allocation to maximize the throughput of the DFTS-OFDMA system under different constraints. The DFTS-OFDMA allowing non-contiguous subcarrier allocation and redundant user assignment provides a better throughput than the SC-FDMA at lower complexity in finding the optimal solution but at the cost of the increased control information indicating the allocated resources.

• Archives of Plastic Surgery
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• v.41 no.2
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• pp.158-162
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• 2014

Background Loss of nipple projection is a common problem following nipple reconstruction. The aim of this study was to demonstrate that the use of a tightly rolled dermal graft is effective in the long-term maintenance of nipple projection. Methods Nipple reconstruction was performed using the C-V flap technique. A dermal graft was harvested from the dog-ear portion of previous scars. The graft was rolled tightly into a compact cylinder and used to augment the nipple reconstruction. Postoperatively, stacked Allevyn dressing was used for protecting the nipple from compression for a minimum of two months. Nipple projection was measured at the time of surgery and at 12 months postoperatively. Results Forty nipple reconstructions were performed using this technique. There were 19 transverse rectus abdominis musculocutaneous (TRAM) flaps, 10 latissimus dorsi (LD) flaps, and 11 tissue-expanded breast mounds. At one year, the mean projection was 0.80 cm (range, 0.62-1.22 cm). The twelve-month average maintenance of nipple projection was 70.2% for the TRAM flap group, 76.3% for the LD flap group, and 61.8% for the tissue-expanded group. In two patients with previous irradiation of the reconstructed breasts, relatively poor maintenance of nipple projection was noted (45.7%). No complications were noted, and all of the donor sites healed well primarily. Conclusions Our results demonstrated that the use of a C-V flap with a tightly rolled dermal graft for nipple reconstruction improves the long-term maintenance of nipple projection. Its advantages include reproducibility, technical simplicity, cost-effectiveness, and minimal donor site morbidity.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.117-125
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• 2020

This paper aims to investigate FDI attractive factors, which are important to formulate policies to attract Korean direct investment into Vietnam. Based on the literature review and the results of interview with 27 Korean investors in Vietnam, we determined the model of variables attracting Korea's FDI into Vietnam. It is used to assess the impact of attractive factors belonging to three groups of variables to support investment decision; they are macroeconomics variables (including market size factor, labor cost factor, and market openness factor), policies variables (including monetary policy factor and tax rate gap factor), and microeconomics variables (geographic advantage factor representative by location). This research also utilized a relatively new quantitative research method based on the Autoregressive Distributed Lag model (ARDL) with the time data chain from 1995 to 2017 of Korean FDI into Vietnam. It analyzes long-term relationships between dependent variables and independent variables. The result of this study indicates that there are three positive factors (low wages, trade openness and government policy) explaining the FDI flows in the long term. The result also shows that incentive tax policy has had a positive impact on Korean FDI, which has satisfied the aim of seeking efficiency of Korean investors.

• Journal of the Korea Convergence Society
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• v.6 no.1
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• pp.71-76
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• 2015

Using a sample of publicly-traded Chinese firms, this study examines a relationship between managerial ownership and corporate debt maturity decisions. China has transformed dramatically into a market capitalist economy over the past decades. However, so far, little attention has been paid to the role of professional managers. In this situation, this study explores the effect of stock grants to managers as incentive system by providing evidence that managerial ownership affects corporate debt maturity decisions. The findings are as follows: First, I find that like US firms, managerial ownership is negatively related to the proportion of long-term debt. Second, I divide the entire sample into two subsamples of state-owned and privately owned firms. For the privately owned firms, I find that there is a negative relationship between managerial ownership and the proportion of long-term debt. In contrast, for the state-owned firms, the relationship is positive and insignificant.