• Education of Primary School Mathematics
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• v.24 no.2
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• pp.103-114
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• 2021

In this study I recognized the problems with the use of the terms 'quotient' and 'reminder' in the division of decimal and explored ways to improve them. The prior studies and current textbooks critically analyzed because each researcher has different views on the use of the terms 'quotient' and 'reminder' because of the same view of the values in the division calculation. As a result of this study, I proposed to view the result 'q' and 'r' of division of decimals by division algorithms b=a×q+r as 'quotient' and 'reminder', and the amount equal to or smaller to q the problem context as a final 'result value' and the residual value as 'remained value'. It was also proposed that the approximate value represented by rounding the quotient should not be referred to as 'quotient'.

• Progress in Medical Physics
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• v.25 no.2
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• pp.72-78
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• 2014

The aim of the study is to test a hypothesis that quasi-breath-hold (QBH) biofeedback improves the residual respiratory motion management in gated 3D thoracic MR imaging, reducing respiratory motion artifacts with insignificant acquisition time alteration. To test the hypothesis five healthy human subjects underwent two gated MR imaging studies based on a T2 weighted SPACE MR pulse sequence using a respiratory navigator of a 3T Siemens MRI: one under free breathing and the other under QBH biofeedback breathing. The QBH biofeedback system utilized the external marker position on the abdomen obtained with an RPM system (Real-time Position Management, Varian) to audio-visually guide a human subject for 2s breath-hold at 90% exhalation position in each respiratory cycle. The improvement in the upper liver breath-hold motion reproducibility within the gating window using the QBH biofeedback system has been assessed for a group of volunteers. We assessed the residual respiratory motion management within the gating window and respiratory motion artifacts in 3D thoracic MRI both with/without QBH biofeedback. In addition, the RMSE (root mean square error) of abdominal displacement has been investigated. The QBH biofeedback reduced the residual upper liver motion within the gating window during MR acquisitions (~6 minutes) compared to that for free breathing, resulting in the reduction of respiratory motion artifacts in lung and liver of gated 3D thoracic MR images. The abdominal motion reduction in the gated window was consistent with the residual motion reduction of the diaphragm with QBH biofeedback. Consequently, average RMSE (root mean square error) of abdominal displacement obtained from the RPM has been also reduced from 2.0 mm of free breathing to 0.7 mm of QBH biofeedback breathing over the entire cycle (67% reduction, p-value=0.02) and from 1.7 mm of free breathing to 0.7 mm of QBH biofeedback breathing in the gated window (58% reduction, p-value=0.14). The average baseline drift obtained using a linear fit was reduced from 5.5 mm/min with free breathing to 0.6 mm/min (89% reduction, p-value=0.017) with QBH biofeedback. The study demonstrated that the QBH biofeedback improved the upper liver breath-hold motion reproducibility during the gated 3D thoracic MR imaging. This system can provide clinically applicable motion management of the internal anatomy for gated medical imaging as well as gated radiotherapy.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.101-106
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• 2016

This paper proposes the SU-SE-MMA algorithm which applying the concept of selective updaing to the SE-MMA that is possible to reduce the intersymbol interference due to distortion occurred at the channel when transmit the nonconstant modulus 16-QAM signal. The SE-MMA emerged for the simplifying the computational operation from the current MMA adaptation algorithm, then it's has the fast convergence speed and has a problem of increase the residual component in the steady state. The SU-SE-MMA performs the selectively tap updating when the distance of equalizer output and specified transmit signal point is greater than the given threshold value and tap updaing does not occurred in the small distance. By this selective updating process, it is possible to more reduction in the computational operation in the propose algorithm. The improved adaptive equalization performance of SU-SE-MMA like as the equalizer output signal constellation, residual isi, MD, SER were confirmed by computer simulation compared to SE-MMA. As a result of simulation, the AV-SE-MMA has better performance in output signal constellation, residual isi and MD compared to the SE-MMA, but it was confirmed that the AV-SE-MMA has similar in the SER performance that means the robustness to the noise.

• Journal of IKEEE
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• v.18 no.2
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• pp.272-281
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• 2014

In electrical impedance tomography (EIT), modified Newton Raphson (mNR) method is widely used inverse algorithm for static image reconstruction due to its convergence speed and estimation accuracy. The unknown conductivity distribution is estimated iteratively by minimizing a cost functional such that the residual error namely the difference in measured and calculated voltages is reduced. Although, mNR method has good estimation performance, EIT inverse problem still suffers from ill-conditioned and ill-posedness nature. To mitigate the ill-posedness, generally, regularization methods are adopted. The inverse solution is highly dependent on the choice of regularization parameter. In most cases, the regularization parameter has a constant value and is chosen based on experience or trail and error approach. In situations, when the internal distribution changes or with high measurement noise, the solution does not get converged with the use of constant regularization parameter. Therefore, in this paper, in order to improve the image reconstruction performance, we propose a new scheme to determine the regularization parameter. The regularization parameter is computed based on residual error and updated every iteration. The proposed scheme is tested with numerical simulations and laboratory phantom experiments. The results show an improved reconstruction performance when using the proposed regularization scheme as compared to constant regularization scheme.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.2
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• pp.96-109
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• 2021

Since terrestrial input plays a major role in coastal primary production, an understanding of land-ocean coupling (LOC) is key to understand coastal ecological changes. In this study, the LOC has been classified into three stages (i.e., the baseflow, plume event and residual flow). In order to characterize its pattern in Nakdong River estuary, multi-platform data were obtained from remote sensing (geostationary ocean color image (GOCI)), in-situ measurement (marine environment information system (MEIS)), on-site measurement (discharge data and meteorological data). The MEIS data were grouped into three stages of LOC using principal component analysis (PCA), and the LOC (2013 ~ 2018) was examined at each stage using multi-platform data. In the Nakdong River estuary, the maximum value of chlorophyll-a (chl-a) was unexpectedly appeared during the plume event. It is assumed that there was no significant increase in turbidity, expected during the typical plume event, together with the weak flushing effect, caused the enhanced phytoplankton growth. Compared with other estuaries, LOC is common in estuaries affected by freshwater inflow, but LOC has different pattern depending on the size of the plume. While estuaries that form small plumes of about 10 km (low freshwater discharge and weak flushing effect) observed high chl-a in the plume event because the phytoplankton can response to the increased nutrient more rapidly. estuaries that form large plumes of more than 100 km est (high freshwater discharge and strong flushing effect) follow the typical LOC pattern conceptualized in this study (high chl-a in the residual flow).

• Journal of the Korean Orthopaedic Association
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• v.54 no.2
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• pp.150-156
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• 2019

Purpose: This study examined the diagnostic accuracy of an imaging study to find the factors that affect the presence of residual tumors after an unplanned excision of sarcomas. Materials and Methods: Ninety-eight patients, who underwent a re-excision after unplanned surgery between January 2008 and December 2014, were enrolled in this study. Magnetic resonance imaging (MRI) was performed before reoperation in all patients. Positron emission tomography (PET)-computed tomography was performed on 54 patients. A wide re-excision and histology diagnosis were performed in all cases. The clinical variables were evaluated using univariate logistic regression and multivariate logistic regression. Results: The presence of a deep-seated tumor increases the risk of remnant tumors (odds ratio: 3.21, p=0.02, 95% confidence interval: 1.25-8.30). The sensitivity for detecting residual tumors is high in MRI (sensitivity 0.79). Conclusion: Deep-seated tumors have a significantly higher risk of remnant tumors. Because the negative predictive value of MRI and PET scans is very low, reoperation should be performed regardless of a negative result.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.240-247
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• 2001

Background : Tuberculous pleurisy treatments improve symptoms such as fever, chest pain, cough, and prevents the progression to active pulmonary tuberculosis and the development of residual pleural thickening that decrease diaphragm and rib cage movement This study investigated how the degree of residual pleural thickening affects the pulmonary function. Methods : Fifty seven patients who were initially diagnosed as having tuberculous pleurisy, were treated with anti-tuberculous medication for 6 months and had residual pleural thickening between May 1998 and January 2000 at the Eulji university hospital were reviewed. A chest X-ray and pulmonary function test(PFT, Sensormedics 2200) were performed. The predicted value(%) of the forced vital capacity(FVC), forced inspiratory vital capacity(FNC) and total lung capacity(TLC) were measured. The residual pleural thickening was defined the average of the summation in the lateral chest at the level of the imaginary line intersecting from the cardiophrenic angle to the diaphragmatic dome and the lowest part of the costophrenic angle between them. The results were sorted into three grades according to pleural thickness ; <2mm(grade I), 2~10mm(grade II), 10mm(grade III). Results : 1. FVC(% pred) and FIVC(% pred) were statistically different between grade I and III, and II and III. However, there was no difference between the TLC(% pred) between each of the groups. 2. The pleural thickness that cause restrictive dysfunction(FVC<80%) and a statistically difference, is 3mm. Conclusion : The larger the extent of the residual pleural thickness after antituberculous medication, the greater the reduction in the FVC, FIVC, TLC. A pleural thickness of 3mm is recommended as a guideline for diagnosing a restrictive pulmonary dysfunction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.586-591
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• 2015

To prepare peach wine using peach juice, fermentation properties were monitored, and fermentation conditions (initial sugar concentration, temperature, and time) were optimized by a response surface methodology. Alcohol content for peach wine fermentation ranged from 3.4~9.2% [$R^2=0.9229$ (P<0.01)] and 8.54% (maximum value) at $18.73^{\circ}Brix$, $16.81^{\circ}C$, and 12.99 day. Acidity ranged from 0.30~0.74%, and 0.25% (minimum value) at $15.11^{\circ}Brix$, $17.09^{\circ}C$, and 13.61 day. Residual sugar concentration was $6.67^{\circ}Brix$ (maximum residual sugar content) at $17.79^{\circ}Brix$, $20.63^{\circ}C$, and 3.37 day. Yellow color intensity was 18.92 (maximum Hunter's color b value) at $13.19^{\circ}Brix$, $20.81^{\circ}C$, and 12.81 day. Based on the above study results, optimization conditions for peach wine fermentation were 9 days, below $20^{\circ}C$, and $19^{\circ}Brix$ peach juice.

• Journal of Wetlands Research
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• v.18 no.2
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• pp.121-131
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• 2016

The determination of feasible design flood is the most important to control flood damage in river management. Concentration time and storage constant in the Clark unit hydrograph method mainly affects magnitude of peak flood and shape of hydrograph. Model parameters should be calibrated using observed discharge but due to deficiency of observed data the parameters have been adopted by empirical formula. This study is to suggest concentration time and storage constant based on the observed rainfall-runoff data at GongDo stage station in the Ansung river basin. To do this, five criteria have been suggested to compute root mean square error(RMSE) and residual of oserved value and computed one. Once concentration time and storage constant have been determined from three rainfall-runoff event selected at the station, the five criteria based on observed hydrograph and computed hydrograph by the Clark model have been computed to determine the value of concentration time and storage constant. A criteria has been proposed to determine concentration time and storage constant based on the results of the observed hydrograph and the Clark model. It has also been shown that an exponent value of concentration time-cumulative area curve should be determined based on the shape of watershed.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.77-82
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• 2008

For the last few decades, forest resources in Korea have continuously increased in terms of their stocks. However, due to the low profitability of timber harvesting in Korea, their economic values have not been well recognized. Furthermore, their economic values have not been counted in national statistics associated with forest resources such as the Forestry Household Economy Survey or the National Accounting. This research fundamentally aimed at building a forest valuation system or a procedure that enables one to evaluate the national-level economic values of timber assets in Korea. For this research, it is necessarily required to understand the principles of appraisal methods and any issues raised in their practical applications. Thus, a comprehensive review of appraisal methods utilized in Korea and other countries was conducted in this research. Also, the current valuation system of the National Forests in Korea was investigated. Through the review and the investigation, it was found that an alternative consists of two appraisal methods, the 'Capitalized Income Value' method adopting the Internal Rate of Return (IRR) for the below-rotation age forest and the 'Derived Residual Value' method for the above-rotation age forest, could be the most acceptable for evaluating timber assets of forestry households derived from the Forestry Household Economy Survey in Korea.