• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.202-202
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• 2011

Diagnostics of plasma density is a key factor for monitoring plasma processing. Various probes are invented to measure plasma density and cut-off probe is a one of the most promising diagnostics tool for measuring plasma density. However, at the low density or high pressure the cut-off probe cannot clearly resolve the cut-off peak. Several reasons make this problem: Cut-off likes peaks caused by cavity resonances and weaken transmission spectrum signal at high pressure. Recently, You et al., have researched mechanism of cut-off probe and we improve the cut-off reliability and sensitivity base on that research. Modified cut-off antenna is adapted and bias cut-off probe method is tried. These experiment results have good agreement with the previous study and show good measurement characteristics.

• The Korean Journal of Applied Statistics
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• v.27 no.3
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• pp.501-512
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• 2014

Modified cut-off sampling is widely used for highly skewed data. A serious drawback of modified cut-off sampling is the difficulty of adjustment of non-response in take-all stratum. Therefore, solutions of the problems of non-response in take-all stratum have been studied in various ways such as substitute of samples, imputation or re-weight method. In this paper, a new cut-off point based on minimizing MSE being used in exponential and power functions is suggested and it can be reduced the number of take-all stratum. We also investigate another cut-off point determination method with underlying distributions such as truncated log-normal and truncated gamma distributions. Finally we suggest the optimal cut-off point which has a minimum of take-all stratum size among suggested methods. Simulation studies are performed and Labor Survey data and simulated data are used for the case study.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.1100-1108
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• 2017

A thermal-hydraulic system code is an essential tool for the design and safety analysis of a nuclear power plant, and its accuracy quantification is very important for the code assessment and applications. The fast Fourier transform-based method (FFTBM) by signal mirroring (FFTBM-SM) has been used to quantify the accuracy of a system code by using a comparison of the experimental data and the calculated results. The method is an improved version of the FFTBM, and it is known that the FFTBM-SM judges the code accuracy in a more consistent and unbiased way. However, in some applications, unrealistic results have been obtained. In this study, it was found that accuracy quantification by FFTBM-SM is dependent on the frequency spectrum of the fast Fourier transform of experimental and error signals. The primary objective of this study is to reduce the frequency dependency of FFTBM-SM evaluation. For this, it was proposed to reduce the cut off frequency, which was introduced to cut off spurious contributions, in FFTBM-SM. A method to determine an appropriate cut off frequency was also proposed. The FFTBM-SM with the modified cut off frequency showed a significant improvement of the accuracy quantification.

• The Korean Journal of Applied Statistics
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• v.17 no.3
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• pp.393-402
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• 2004

We suggest a summary of sample design for the statistical survey of E-commerce to estimate the general trend as well as the market size and investment scale of e-commerce based on the Census on Basic Characteristic of Establishments(CBCE). The sample design of this survey is composed of systematic sampling and modified cut-off method.

• Food Science and Industry
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• v.50 no.2
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• pp.12-26
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• 2017

Processing steps such as washing and cutting, involved in preparing fresh-cut produce causes tissue damage, leading to rapid quality deterioration. Major defects of fresh-cut produce are discoloration, softening, off-odor development, and microbial growth. Packaging of fresh-cut produce has been changed to reduce these quality problems. Flexible packaging film is widely used to pack fresh-cut produce. Vacuum packaging was the popular packaging method in the beginning of fresh-cut industry in Korea. Vacuum packaging creates high $CO_2$ and low $O_2$ levels to control browning of fresh-cut produce. However, these conditions induce some visual defects and off-odor development. Discoloration problem was also found when fresh-cut produce was packaged with conventional packaging film or plastic tray. Modified atmosphere (MA) packaging is effective for prolonging shelf-life of fresh-cut produce by decreasing $O_2$ and increasing $CO_2$ concentration in the package. Retail MA packaging using different oxygen transmission rate (OTR) film and micro-perforated film has started to be applied to fresh-cut produce in Korea. Proper MA package design that provides optimum range of $O_2$ and $CO_2$ partial pressures is one of the major challenges in the industry. An initial package flushing with $N_2$ or an low $O_2$/high $CO_2$ atmosphere is also used to more rapidly establish steady-state MA condition. Film OTR and $O_2$ flushing affects the fermentative volatile production, off-odor development, electrolyte leakage, discoloration, $CO_2$ injury, microbial population of fresh-cut produce. There is also a demand for convenient packaging to attract consumers. Rigid fresh-cut produce container for retail market has increased since the packaging provides excellent protection from physical damage during transport. Rigid tray used as actual serving vessel for the consumer is increasing in Korea. The tray with flexible lid to wrap or seal fresh-cut produce is more and more gaining popularity. Further practical technology to control quality change and microbial growth for each fresh-cut product has been studied since various fresh-cut items were required. The fresh-cut industry also focuses on searching for more convenient and environmentally friendly packaging.

• Communications for Statistical Applications and Methods
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• v.15 no.6
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• pp.883-897
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• 2008

This paper provides correct informations inflecting the present situation using the sample design in population that the National Statistical Office puts in operation of the mining and manufacturing industry statistical survey in 2006. This paper proposes new sampling design which is able to grasp business fluctuations and provide basic data for the rearing policy and management of the material industry and components industry. These sample design are the modified cut-off method and multivariate Neyman allocation using principal components and sampling method is the probability proportional systematic sampling.

• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.476-481
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• 2023

Objective : The latest version of the Leksell Gamma Knife Icon^TM allows for mask- and frame-based fixation. Although mask fixation provides fractionated treatment and immobilization using a noninvasive method, it is not free from collision. The authors investigated the collision problem with a modified mask fixation method. Methods : This study presents a case of two meningiomas in the frontal area, where a collision occurs in the occipital area. A modified mask fixation method was introduced to avoid the collision : first, the edges of the head cushion were cut off and polystyrene beads with a diameter of approximately 5 cm were removed. Next, the head cushion was sealed using a stapler. Finally, the head cushion was flattened in the adapter. We compared the shot coordinates, 3-dimensional (3D) error, clearance distance, and vertical depth of the head cushion between the initial and modified mask fixations. Results : When comparing the initial and modified mask fixations, the difference in the shot coordinates was +10.5 mm along the y-axis, the difference in the 3D error was approximately 18 mm, and the difference in clearance was -10.2 mm. The head cushion was approximately 8 mm deeper in the modified mask fixation. Conclusion : Based on these findings, we recommend a modified mask fixation method for gamma knife radiosurgery using ICON with a collision.

• Nuclear Engineering and Technology
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• v.6 no.2
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• pp.89-96
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• 1974

The cross-section ratios of the nuclear isomeric pairs $^{80}$ B $r^{m, g}$, sup 81/S $e^{m, g}$, $^{104}$ R $h^{m, g}$, $^{116}$ I $n^{m, g}$ and $^{134}$ C $s^{m, g}$ through the radiative thermal neutron capture process have been studied. The experimental values of these ratios obtained by the activation method have been compared with the calculated ones deduced from the modified Huizenga-Vandenbosch method. Agreement between these values within 30% could be attained by controlling the spin cut-off parameter and gamma-ray multiplicity.

• Proceedings of the Korean Statistical Society Conference
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• 2003.10a
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• pp.59-62
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• 2003

양곡소비량조사는 가구부문과 사업체부문에서 소비하는 주요식품의 소비량을 조사함과 동시에 주곡인 쌀의 재고량을 조사한다. 이 조사는 해마다 통계청에서 표본설계하여 실시하는 표본조사에 의존한다. 특히, 사업체 부문의 양곡소비량 조사는 응용절사법(Modified Cut-Off Sampling Method)에 의해 표본추출되어 매년 11월에 조사가 실시되고 있다. 2003년도 사업체 양곡소비량 및 재고량조사는 2001년 사업체기초통계조사와 광공업통계조사를 모집단으로 하여 22,320 대상업체 중에서 819업체를 전수조사하고 2,145 업체를 표본조사하여 전체를 추계한다.

• Korean Journal of Health Education and Promotion
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• v.27 no.1
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• pp.105-113
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• 2010

Objcetive: The purpose of this study was to establish body mass index percentiles and cutoffs for overweight and obesity in East Asian Adolescent. Methods: Based on one's age and gender, subjects were selected and measured their weight and height in order to calculate BMI. For BMI cut off points, data were analyzed and percentile curves were established by the modified LMS method. Results were followed by comparing BMI cut off points and percentiles with one's nationality, age and gender. Results: The prevalence of male's overweight and obesity among East Asian adolescent were as follows: Taiwan (15.4%, 9.0%), Korean (14.5%, 8.5%), Chinese (13.3%, 6.6%), and Japanese (6.0%, 2.1%). And for female, Korean (13.1%, 3.7%), Taiwan (12.6%, 5.1%), Chinese (8.3%, 2.3%) and Japanese (7.9%, 3.1%) were in the order. Conclusion: Corresponded to the whole subjects, 11.0% of men were overweight, 4.7 were obesity and that appeared in women with 9.0% in overweight, 3.5% were obese.