• Annals of Clinical Neurophysiology
• /
• v.5 no.1
• /
• pp.27-33
• /
• 2003

Background: Motor unit number estimation (MUNE) can directly assess motor neuron populations in muscle and quantify the degree of physiologic and/or pathologic motor neuron degeneration. A high degree of reproducibility and reliability is required from a good quantitative tool. MUNE, in various ways, is being increasingly applied clinically and statistical MUNE has several advantages over alternative techniques. Nevertheless, the optimal method of applying statistical MUNE to improve reproducibility has not been established. Methods: We performed statistical MUNE by selecting the most compensated compound muscle action potential (CMAP) area as a test area and modified the results obtained by weighted mean surface-recorded motor unit potential (SMUP). Results: MUNE measures in amyotrophic lateral sclerosis (ALS) patients showed better reproducibility with sizeweighted modification. Conclusions: We suggest size-weighted MUNE testing of "neurogenically compensated"CMAP areas present an optimal method for statistical MUNE in ALS patients.

• Communications for Statistical Applications and Methods
• /
• v.13 no.2
• /
• pp.205-217
• /
• 2006

In this paper, we consider the problem of testing for a change of the parameter function ${\theta}(t)$ that may have a discontinuity at some unknown point ${\tau}$. We introduce a varying-h moving estimate to test the null hypothesis that ${\theta}(t)$ is continuous against the alternative that ${\theta}({\tau}-){\neq}{\theta}({\tau}+)$. Simulation results are provided for illustration.

• Communications for Statistical Applications and Methods
• /
• v.17 no.6
• /
• pp.829-843
• /
• 2010

To test for the serial dependence in time series of counts data, Jung and Tremayne (2003) evaluated the size and power of several tests under the class of INARMA models based on binomial thinning operations for Poisson marginal distributions. The overdispersion phenomenon(i.e., a variance greater than the expectation) is common in the real world. Overdispersed count data can be modeled by using alternative thinning operations such as random coefficient thinning, iterated thinning, and quasi-binomial thinning. Such thinning operations can lead to time series models of counts with negative binomial or generalized Poisson marginal distributions. This paper examines whether the test statistics used by Jung and Tremayne (2003) on serial dependence in time series of counts data are affected by overdispersion.

• International Journal of Stem Cells
• /
• v.17 no.2
• /
• pp.147-157
• /
• 2024

The objective of standard guideline for utilization of human lung organoids is to provide the basic guidelines required for the manufacture, culture, and quality control of the lung organoids for use in non-clinical efficacy and inhalation toxicity assessments of the respiratory system. As a first step towards the utilization of human lung organoids, the current guideline provides basic, minimal standards that can promote development of alternative testing methods, and can be referenced not only for research, clinical, or commercial uses, but also by experts and researchers at regulatory institutions when assessing safety and efficacy.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.34 no.2
• /
• pp.176-183
• /
• 2014

Acoustic emission testing (AET) of cylinders is advantageous in that it can be directly conducted on cylinders installed in a car, without needing to dissemble them on a real-time basis. Therefore, users prefer AET over other nondestructive testing methods. Owing to these advantages of AET, it has been approved by the Department of Transportation of the U.S. as a safety evaluation method for pressure containers or as an alternative to the hydroproof testing method. This paper presents a study of the quantitative evaluation criteria for a container having ultrasonic testing defects and also for Type 1 and Type 2 gas cylinders, which are defective seamless pressure containers provided by NK, a manufacturer of pressure containers. For the Type 1 cylinder, the process from crack growth to leak was observed in a repetitive fatigue test using a 113 L container according to ASTM E 1419-02. Further, for the Type 2 cylinder, integrity was evaluated using a 119 L sound container and a container damaged by hydraulic pressure, by the slow-fill method according to ASTM E 2191-02. Based on the AET results of the Type 1 and Type 2 cylinders, quantitative evaluation criteria were established for a defective and non-defective container.

• Journal of Food Hygiene and Safety
• /
• v.12 no.2
• /
• pp.132-140
• /
• 1997

Additives in plastics are capable of migrating from the packaging materials into the foodstuffs, thereby presenting a source of contamination and a potential health risk to the consumer. The migration from packaging materials into foodstuffs is first of all regulated by examining the amounts of global and specific migrated components. Besides, there is worldwide still a need for practical methods for measuring and monitoring migration from polymers, especially for the testing of migration into fatty foodstuffs. Therefore, these studies were undertaken to investigate the safety status of domestic plastic packaging materials with respect to migration. Another objective of this study was to examine the applicability of ethanol as an alternative fatty food simulant substituting for olive oil and n-heptane. The evaporation residues for various dometic plastic samples determined as described in Korean food laws were in the level from 4.3 to 14.5 mg/$\ell$, which were much lower than the limit value of 150 mg/$\ell$. The global migration values into 95 % ethanol showed to be comparable to those into n-heptane, while the olive oil migration values were comparably higher than those into ethanol or n-heptane and moreover they were not reproducible. The kinetic migration begavior of additives in polyolefin samples into 95% ethanol showed a Fickian diffusion process. The results of these studies on global migration and kinetic testings demonstrate that the ethanol could be successfully substitute for the olive oil and n-heptane as an alternative fatty food simulant, at least in contact with polyoefins.

• Geomechanics and Engineering
• /
• v.38 no.5
• /
• pp.529-539
• /
• 2024

A high-level nuclear waste (HLW) repository is designed for the long-term disposal of high-level waste. Positioned at depths of 500-1000 meters, it offers an alternative to the insufficient storage space for spent fuels, providing a long-term solution. High-level waste emits heat and radiation, causing structural deterioration, including strength reduction and cracks. Therefore, the use of piezoelectric sensors for structural health monitoring is essential for evaluating the safety of the structure over time. Unlike other structures, the HLW repository restricts human access after the disposal of HLW, rendering sensor replacement impossible. Therefore, it is necessary to assess both the lifespan and suitability of sensors under the disposal conditions in the HLW repository. This study employed an accelerated life test (ALT) to assess the sensor's lifespan under disposal conditions. Failure modes, failure mechanisms, and operational limits were analyzed through accelerated stress test (AST). Additionally, the parameters of the Weibull life probability distribution and the Arrhenius accelerated life model were estimated through statistical methods, including the likelihood ratio test, maximum likelihood estimation, and hypothesis testing. Results confirmed that the sensor's lifespan decreases significantly with the increase in the temperature limit of the HLW repository. The findings of this study can be used for improving sensor lifespan through shielding, development of alternative sensors, or lifespan evaluation of alternative monitoring sensors.

• Journal of Electrical Engineering and Technology
• /
• v.4 no.4
• /
• pp.559-565
• /
• 2009

Power dissipation during scan testing is becoming an important concern as design sizes and gate densities increase. The high switching activity of combinational circuits is an unnecessary operation in scan shift mode. In this paper, we present a novel architecture to reduce test power dissipation in combinational logic by blocking signal transitions at the logic inputs during scan shifting. We propose a unique architecture that uses dmuxed scan flip-flop (DSF) and transmission gate as an alternative to muxed scan flip-flop. The proposed method does not have problems with auto test pattern generation (ATPG) techniques such as test application time and computational complexity. Moreover, our elegant method improves performance degradation and large overhead in terms of area with blocking logic techniques. Experimental results on ITC99 benchmarks show that the proposed architecture can achieve an average improvement of 30.31% in switching activity compared to conventional scan methods. Additionally, the results of simulation with DSF indicate that the powerdelay product (PDP) and area overhead are improved by 28.9% and 15.6%, respectively, compared to existing blocking logic method.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.24
• /
• pp.10809-10812
• /
• 2015

Background: Human papillomavirus (HPV) DNA testing is an effective method to screen for precancerous changes in the cervix. Samples from self-collection rather than Pap smear can potentially be used to test for HPV as they are more acceptable and preferred for use in certain settings. The objective of this study was to compare HPV DNA testing from self-collected vaginal swabs and physician-collected cervical swabs. Materials and Methods: A total of 101 self-collected vaginal and physician-collected cervical swabs of known cytology from Thai women were tested by electrochemical DNA chip assay. The specimens were divided into 4 groups: 29 with normal cytology, 14 with atypical squamous cells of undetermined significance (ASCUS), 48 with low-grade squamous intraepithelial lesion (LSIL), and 10 with high-grade squamous intraepithelial lesion (HSIL). Results: Positive detection rates of HPV from self-collected swabs were similar to those from physician-collected swabs. Among specimens with abnormal cytology, HPV was found in 50% of self-collected swabs and 47.2% of physician-collected swabs. In specimens with normal cytology, 17.2% of self-collected swabs and 24.1% of physician-collected swabs were positive for HPV. Concordance was relatively high between results from self-collected and physician-collected samples. The most common HPV genotype detected was HPV 51. Conclusions: HPV DNA testing using self-collected swabs is a feasible alternative to encourage and increase screening for cervical cancer in a population who might otherwise avoid this important preventive examination due to embarrassment, discomfort, and anxiety.

• Journal of Korean Library and Information Science Society
• /
• v.24
• /
• pp.107-161
• /
• 1996

This study aims at introducing 'ethnography' which is one of the most representative qualitative research methods into Library and Information Science research in Korea.. Ethnography, derived from anthropology, helps researchers to understand the whole and deep aspect of the research object. That is because the researcher puts himself into the life-world of the research object and observes it for a long time. Ethnography can be used as an alternative method to quantitative research methods. Until now, Library and Information Science research in Korea has used quantitative research methods in almost every case. From the 1980s so-called 'scientific methods' using hypotheses testing, have provided the major premise for research methodology in Library and Information Science of Korea. And the researchers have seen their research object(Korean Libraries) not in the native perspective but largely in the western(especially American) perspective. There is a need in Korea for more culturally relative research. So the desirability of introducing ethnography and other qualitative research methods into Library and Information Science research in Korea can be summarized as follows : I. Ethnography and other qualitative methods are needed for the researchers to overcome the limitation of quantitative methods which have formed the main methodological paradigm in Library and Information Science research in Korea. While those quantitative scientific methods can be a n.0, pplied to the social sciences, they are not adequate for the social sciences. It is because the research objects of the social sciences are human and social phenomena. II. It is needed that Library and Information Science research in Korea pay more attention to the speciality of Korean libraries. To do researches based on the viewpoint of cultural-relativism, researchers should consider the cultural context of Korean libraries. During the past years researchers in other social science fields in Korea, especially sociology and pedagogy, have gradually a n.0, pplied the methods of ethnography to their fields. These social scientists have attempted to escape from ethnocentrism, a problem which has greatly influenced past and present research methods. To get a holistic and in-depth understanding of Korean libraries on the present stage, and to solve their problems radically, it seems imperative that Library and Information Science research in Korea pay more attention to qualitative research methods such as ethnography.