• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2027-2034
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• 2008

There are concerns on possible health effects from exposure to electromagnetic fields. One reflection of this concerns is the considerable controversy, delay, and cost increases involved in the construction of power lines and facilities. To cope with such challenges, in this paper we investigated magnetic fields reduction techniques such as general compaction, in' span compaction, cruciform, vertical, 3 way splits phase, and 4way splits phase. As results, we found general compaction and 4 way splits phase could reduce magnetic fields up to 90%, while cruciform, vertical, and 3 way splits phase gave lower reduction rates of 30% because these configurations were similar to a current type of low reactance arrangement. We also knew 1 spacer in span compaction was appropriate in Korea in view of effectiveness and economy.

• Journal of Powder Materials
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• v.19 no.5
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• pp.356-361
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• 2012

The ultra-fine and less agglomerated titanium carbonitride particles were successfully synthesized by magnesiothermic reduction with low feeding rate of $TiCl_4+1/4C_2Cl_4$ solution. The sub-stoichiometric titanium carbide ($TiC_{0.5{\sim}0.6}$) particles were produced by reduction of chlorine component by liquid magnesium at $800^{\circ}C$ of gaseous $TiCl_4+1/4C_2Cl_4$ and the heat treatments in vacuum were performed for 5 hours to remove the residual magnesium and magnesium chloride mixed with produced $TiC_{{\sim}0.5}$. The final $TiC_{{\sim}0.5}N_{0{\sim}0.5}$ particle with near 100 nm in mean size and high specific surface area of $65m^2/g$ was obtained by nitrification under nitrogen gas at $1,150^{\circ}C$ for 2 hrs.

• Archives of Craniofacial Surgery
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• v.17 no.4
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• pp.186-189
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• 2016

Frontal sinus fractures, particularly anterior sinus fractures, are relatively common facial fractures. Many agree on the general principles of frontal fracture management; however, the optimal methods of reduction are controversial. The subbrow approach enables accurate reduction and internal fixation of the fractures in the anterior table of the frontal sinus by allowing direct visualization of the fracture. Given the surgical success in reduction and rigid fixation, patient satisfaction, and aesthetic benefits, the transcutaneous approach through a subbrow incision is superior to other reduction techniques used in the management of an anterior table frontal sinus fracture.

• Communications for Statistical Applications and Methods
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• v.13 no.1
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• pp.19-27
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• 2006

Outliers in survey are a perennial problem for applied survey statisticians to estimate the total or mean of population. The influence of outliers is more increasing as they have large weights in survey sampling. Many techniques have been studied to lower the impact of outliers on sample survey estimates. Outliers can be downweighted by winsorization or reducing the weight of outliers. The weight reduction is more reasonable than replacing one outlier by one value of non-outliers, because it has at least one unit. In this paper, we suggest the square root transformation of weight as the weight reduction method. We show this method is efficient with real data, and it's also easy to apply in practical affairs.

• The Korean Journal of Ceramics
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• v.4 no.4
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• pp.387-393
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• 1998

The formation of titanium diboride ($TiB_2$ ) via the reduction of $TiO_2$ with boric oxide and carbon was studied in a partially reducing atmosphere of argon mixed with 4 vol.%H2. The effect of reaction time, temperature, partial pressure of nitrogen and $TiO_2/B_2_O3$ stoichiometric ratio on the reducibility of oxides has been studied. The phases formed were analysed by using X-ray rowder diffraction and scanning sosctron microscopic techniques. In this paper, we also investigated the presence of $CaC_2$ as a reducing agent on the reducibility of oxide mixtures and on the Ti-B-C-Ca-O phase equilibria. The morphology of $TiB_2$ formed in the presence of $CaC_2$ is compared with the microstructure of $TiB_2$ formed as a consequence of carbothermic reduction. The observed variation in $TiB_2$ crystals formed is also explained.

• Journal of Environmental Science International
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• v.24 no.8
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• pp.1065-1073
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• 2015

Urbanization can be significantly affected the hydrologic cycle by increasing flood discharge and heat flux. In order to mitigate these modifications in urban areas, Low Impact Development (LID) technique has been designed and applied in Korea. In order to estimate runoff reduction rate using SWMM LID model, the characteristics of five LID techniques was firstly analyzed for water balance. Vegetated swale and green roof were not reduce flood discharge nor infiltration amount. On the other hand, porous pavement and infiltration trench were captured by infiltration function. The flood reduction rate with LID is substantially affected by their structures and properties, e.g., the percentage of the area installed with LID components and the percentage of the drainage area of the LID components.

• The Journal of Information Technology and Database
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• v.1 no.2
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• pp.25-35
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• 1994

Downsizing IS is rapidly emerging as one of new information systems of the 1990s that involves (1) the cost reduction, (2) the reduction of MIS staff, and (3) the transfer of IS functions to end - users. As downsizing is relatively new information systems, little is known about the causes, the process, or the consequences of downsizing. Case study was chosen as the research methodology of this study. The downsizing IS of Namsun Aluminum Co. Ltd. in Taugu City was chosen for the exploratory case study. The detailed and qualitative analyses to Namsun were performed with the use of observation, participation, and interview techniques. Consequently, the causes, the process, and the consequences of Namsun's downsizing were analyzed and discussed. As for the main cause, downsizing was started with the purpose of cost reduction. The important consequences of downsizing IS are as follows : (1) About 700 million won reduction in the cost of initially developing the downsizing was achieved. (2) Downsizing is performing Namsun's mission critical applications. (3) Namsun's downsizing could be considered to be SIS(strategic information systems).

• Electronics and Telecommunications Trends
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• v.34 no.2
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• pp.83-91
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• 2019

In this article, we introduce examples and technologies relating to particulate matter (PM) reduction technology, for the purpose of reducing PM that harms health and affects the entire industry such as dust-sensitive semiconductor industry. First, the definition of PM and how it is generated is explained, including its effects on the human body. In addition, various methods for measuring PM are described, including examples of the restrictions on the operation of polluting vehicles and emission reduction devices. Finally, we describe techniques relating to the reduction and forecasting of PM.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.680-686
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• 2008

Purpose: Breast conserving surgery(BCS) for breast cancer has a common treatment protocol. Oncoplastic surgery represents a form of BCS which combines both a cosmetic mammoplasty approach and oncologic resection for the treatment of breast cancer. Depending on the tumor site, BCS can make an unsatisfactory cosmetic result, especially in inferiorly placed tumors. This study describes the use of oncoplastic techniques for inferiorly located breast tumors in immediate partial mastectomy reconstruction. Methods: From September of 2006 to February of 2008, these techniques were used in 11 patients at the ${\bigcirc}{\bigcirc}$ hospital. After BCS was preceded, breast reshaping by oncoplastic techniques were selected depending on the location and size of the tumor within the breast as well as the size of breast itself. Oncoplastic techniques after partial mastectomy included 'Wise pattern (inverted T)' reduction mammoplasty, 'vertical pattern' mammoplasty, 'J-pattern' mammoplasty. In order to improve the cosmetic outcome, repositioning of the nipple areola complex(NAC) or reshaping of the contralateral breast may be considered additionally. Results: These techniques have been used in 11 patients. The mean age was 51 and the average follow-up period was 8 months. Eleven of these patients underwent the 'Wise pattern(inverted T)' reduction mammoplasty(n=6), 'vertical pattern' mammoplasty(n=3) and 'J-pattern' mammoplasty(n=2). There was one wound dehiscence during the follow-up periods. This complication was treated by conservative approach. The overall cosmetic result was evaluated in 6 months. The majority of patients were satisfied at the cosmetic result. Conclusion: Oncoplastic techniques in inferiorly located breast tumors could be a reasonable and safe option for breast cancer patients who desire conserving surgery with esthetical breast.

• Clinics in Shoulder and Elbow
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• v.25 no.3
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• pp.224-229
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• 2022

Background: Most acromioclavicular joint (ACJ) injuries are caused by direct trauma to the shoulders, and various methods and techniques are used to treat them; however, none of the options can be considered the gold standard. This study examines the horizontal stability of the ACJ after a complete dislocation was repaired using one of two Ethibond suture techniques, the loop technique and the two holes in the clavicle technique. Methods: In this single-blind, randomized clinical trial, 104 patients diagnosed with complete ACJ dislocation type V were treated using Ethibond sutures with either the loop technique or the two holes in the clavicle technique. Horizontal changes in the ACJ were radiographically assessed in the lateral axial view, and shoulder function was evaluated by the Constant (CS) and Taft (TS) scores at intervals of 3, 6, and 12 months after surgery. Results: The horizontal stability of the ACJ was better with the two-hole technique than the loop technique at all measurement times. CS and TS changes showed a significant upward trend over time with both techniques. The mean CS and TS at the final visit were 95.2 and 11.6 with the loop technique and 94.0 and 11.9 with the two-hole technique, respectively. The incidence of superficial infections caused by the subcutaneous pins was the same in the two groups. Conclusions: Due to the improved ACJ stability with the two-hole technique, it appears to be a more suitable option than the loop technique for AC joint reduction.