• 대한예방의학회:학술대회논문집
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• 1994.02b
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• pp.206-233
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• 1994

The Medical Research Council has for some years encouraged collaborative clinical trials in leukaemia and other cancers, reporting the results in the medical literature. One unreported result which deserves such publication is the development of the expertise to design and analyse such trials. This report was prepared by a group of British and American statisticians, but it is intended for people without any statistical expertise. Part!, which appears in this issue, discusses the design of such trials; Part II, which will appear separately in the January 1977 issue of the Journal, gives full instructions for the statistical analysis of such trials by means of life tables and the logrank test, including a worked example, and discusses the interpretation of trial results, including brief reports of particular trials. Both parts of this report are relevant to all clinical trials which study time to death, and would be equally relevant to clinical trials which study time to other particular classes of untoward event: first stroke, perhaps, or first relapse, metastasis, disease recurrence, thrombosis, transplant rejection, or death from a particular cause. Part I, in this issue, collects together ideas that have mostly already appeared in the medical literature, but Part II, next month, is the first simple account yet published for non-statistical physicians of how to analyse efficiently data from clinical trials of survival duration. Such trials include the majority of all clinical trials of cancer therapy; in cancer trials, however, it may be preferable to use these statistical methods to study time to local recurrence of tumour, or to study time to detectable metastatic spread, in addition to studying total survival. Solid tumours can be staged at diagnosis; if this, or any other available information in some other disease is an important determinant of outcome, it can be used to make the overall logrank test for the whole heterogeneous trial population more sensitive, and more intuitively satisfactory, for it will then only be necessary to compare like with like, and not, by chance, Stage I with Stage III.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.19-26
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• 2017

Objectives: Recently, bioceramic sealers like EndoSequence BC Sealer (BC Sealer) have been introduced and are being used in endodontic practice. However, this sealer has limited research related to its retreatability. Hence, the aim of this study was to evaluate the retreatability of two sealers, BC Sealer as compared with AH Plus using micro-computed tomographic (micro-CT) analysis. Materials and Methods: Fifty-six extracted human maxillary incisors were instrumented and randomly divided into 4 groups of 14 teeth: 1A, gutta-percha, AH Plus retreated with chloroform; 1B, gutta-percha, AH Plus retreated without chloroform; 2A, gutta-percha, EndoSequence BC Sealer retreated with chloroform; 2B, gutta-percha, EndoSequence BC Sealer retreated without chloroform. Micro-CT scans were taken before and after obturation and retreatment and analyzed for the volume of residual material. The specimens were longitudinally sectioned and digitized images were taken with the dental operating microscope. Data was analyzed using an ANOVA and a post-hoc Tukey test. Fisher exact tests were performed to analyze the ability to regain patency. Results: There was significantly less residual root canal filling material in the AH Plus groups retreated with chloroform as compared to the others. The BC Sealer samples retreated with chloroform had better results than those retreated without chloroform. Furthermore, patency could be re-established in only 14% of teeth in the BC Sealer without chloroform group. Conclusion: The results of this study demonstrate that the BC Sealer group had significantly more residual filling material than the AH Plus group regardless of whether or not both sealers were retreated with chloroform.

• Diabetes and Metabolism Journal
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• v.42 no.6
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• pp.488-495
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• 2018

Background: Skeletal muscle plays a major role in glucose metabolism. We investigated the association between thigh muscle mass, insulin resistance, and incident type 2 diabetes mellitus (T2DM) risk. In addition, we examined the role of body mass index (BMI) as a potential effect modifier in this association. Methods: This prospective study included 399 Japanese Americans without diabetes (mean age 51.6 years) who at baseline had an estimation of thigh muscle mass by computed tomography and at baseline and after 10 years of follow-up a 75-g oral glucose tolerance test and determination of homeostasis model assessment of insulin resistance (HOMA-IR). We fit regression models to examine the association between thigh muscle area and incidence of T2DM and change in HOMA-IR, both measured over 10 years. Results: Thigh muscle area was inversely associated with future HOMA-IR after adjustment for age, sex, BMI, HOMA-IR, fasting plasma glucose, total abdominal fat area, and thigh subcutaneous fat area at baseline (P=0.033). The 10-year cumulative incidence of T2DM was 22.1%. A statistically significant interaction between thigh muscle area and BMI was observed, i.e., greater thigh muscle area was associated with lower risk of incident T2DM for subjects at lower levels of BMI, but this association diminished at higher BMI levels. Conclusion: Thigh muscle mass area was inversely associated with future insulin resistance. Greater thigh muscle area predicts a lower risk of incident T2DM for leaner Japanese Americans.

• Journal of Pharmacopuncture
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• v.25 no.3
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• pp.224-232
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• 2022

Objectives: Routine therapies cannot control refractory stable angina, leading to a high economic burden and an impaired quality of life. Persian medicine incorporates exceptional attention to lifestyle and nutrition to prevent and treat various diseases. Previous studies have reported the analgesic and anti-inflammatory effects of wet cupping. The present study aims to determine the effects of nutrition and cupping on refractory stable angina patients. Methods: Forty male patients with refractory stable angina were randomly allocated to four groups, including nutrition modification based on Persian medicine, wet cupping, nutrition modification along with wet cupping, and control. The primary outcomes were the changes in pain score using a visual analog scale and quality of life using the Seattle angina questionnaire. The secondary outcomes were changes in the exercise test and blood pressure. Results: The results of the present study revealed that 30 days of treatment with nutrition modification based on Persian medicine, cupping, and modified nutrition and cupping along with standard treatment for stable angina significantly increased the patient's quality of life and exercise test results while reducing pain, and systolic and diastolic blood pressure. Conclusion: Applying complementary Persian medicine methods such as nutrition modification and cupping along with the classical medical treatments may improve outcomes for refractory stable angina patients.

• Advances in nano research
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• v.12 no.1
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• pp.81-99
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• 2022

The aim of current work is to evaluate thermo-electrical characteristics of graphene nanoplatelets Reinforced Composite (GNPRC) coupled with magneto-electro-elastic (MEE) face sheet. In this regard, a cylindrical smart nanocomposite made of GNPRC with an external MEE layer is considered. The bonding between the layers are assumed to be perfect. Because of the layer nature of the structure, the material characteristics of the whole structure is regarded as graded. Both mechanical and thermal boundary conditions are applied to this structure. The main objective of this work is to determine critical temperature and critical voltage as a function of thermal condition, support type, GNP weight fraction, and MEE thickness. The governing equation of the multilayer nanocomposites cylindrical shell is derived. The generalized differential quadrature method (GDQM) is employed to numerically solve the differential equations. This method is integrated with Deep Learning Network (DNN) with ADADELTA optimizer to determine the critical conditions of the current sandwich structure. This the first time that effects of several conditions including surrounding temperature, MEE layer thickness, and pattern of the layers of the GNPRC is investigated on two main parameters critical temperature and critical voltage of the nanostructure. Furthermore, Maxwell equation is derived for modeling of the MEE. The outcome reveals that MEE layer, temperature change, GNP weight function, and GNP distribution patterns GNP weight function have significant influence on the critical temperature and voltage of cylindrical shell made from GNP nanocomposites core with MEE face sheet on outer of the shell.

• Journal of the Korean Geotechnical Society
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• v.24 no.6
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• pp.37-44
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• 2008

At low normal stress levels, tensile strength of sand characteristically varies with either saturation or suction of soil in an up-and-down manner with a peak tensile strength that can occur at any degree of saturation. A theory that accurately predicts tensile strength of wet sand was presented in the previous study. In this study, the results of uniaxial tensile, suction-saturation and direct shear tests obtained from three sands (Esperance sand from Seattle, Washington, clean sand from Perth, Australia, and Ottawa sand) are used to validate the proposed theory. The closed form expression of the proposed theory can predict well the experimental data obtained from these sands in terms of the variation patterns of tensile strength over the entire saturation regimes, the magnitude of the tensile strength, its peak value, and the corresponding degree of saturation when the peak strength occurs.

• Journal of Korean Academy of Nursing
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• v.23 no.2
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• pp.299-315
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• 1993

Koreans are one of the fastest growing immigrant groups in America. Stress responses and stressors among this large cultural minority has been rarely been studied by nursing researchers. Adjusting to life in foreign country produces a great deal of stress. Differences in culture, language, expectations and social behavior can lead to misunderstandings between health care providers and clients. These misunderstandings are not well accounted for in health assessment. This study investigated the relationship between life events or / and daily activities as a stressor and the symptoms of stress among a sample of Korean immigrants in America. The symptoms of stress scale (SOS) was used to identify stress responses and open-ended questions were used to identify life events and daily activities considered by the respondents to be stressful. A simple random sample of 283 subjects was selected from the Directory of the Korean Society of Chicago, New York, Los Angeles, Philadelphia and Seattle. Demographically, the subjects ranged in age from 20 to 69 years, and the percentage of women and men was approximately 50% each. Almost ninety percent of the subjects were highly educated, 17% owners of business, 19% white collar professionals, 14% employed in sales or as skilled /unskilled labor, 27% as housewives and students and 3％ had no occupation. The total group SOS mean was 0.8042 ; the SOS men for man was 0.7371, and for women was 0.8713. The stress response of this subject group was high, -the stress response of women higher than that for men. In an earlier study(June, 1992) with another sample, the total mean SOS score was similar to this one. The main stressful life events or / and daily activities were, in order, economic problems (N=97), interpersonal problems (N=68), children care problems (N=258), health problems (N=49), communication problems (N=42), family problems (N=38), worry about future career (N=36), and religious problems (N=25). There was a significant difference in the SOS means between the group that expressed life events or / and daily activities to be stressful and the group that did not. Interpersonal relationships and economic and family problems were stressors for those who complained about peripheral manifestations. cardiopulmonary symptoms, central-neurological symptoms, gastrointestinal symptoms, muscle ten-sion, habitual patterns, depression, anxiety, emotional irritability and cognitive disorganization. In summary, interpersonal relationships and economic and family problems influenced stress response manifestations. Income, the number of people in the family, the year of immigration. the level of education, and marital status were related to physiological and psychosocial stress responses.

• Industry Promotion Research
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• v.5 no.3
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• pp.11-22
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• 2020

Recently, developed countries have been suffering from a weakening sense of community due to low birthrate, aging population, rapid population movement, rapid urbanization, and industrialization. As a result, participation in local autonomy of residents in advanced countries such as the U.S. and Japan is forming community organizations at the regional level. The purpose of this study is to study the legal system of American and Japanese village enterprises. We would also like to analyze the legal system of village enterprises in the United States and Japan and examine the examples of the legal system of village enterprises in the United States and Japan. Specifically, the first is to consider the concept, background, and type of village enterprise based on prior research. Second, review the institutional characteristics of American and Japanese village enterprises. Third, I would like to analyze the cases of legal systems for village businesses such as Seattle City in the U.S. and Setaga Baseball in Tokyo, Japan. Fourth, suggest implications according to the results of the study. The results of the study suggested the following. First, the village development project should be set up and subdivided into dedicated administrative organizations. This should establish a segmented administrative organization system to support village development by establishing branch offices to support administrative services tailored to each region. Second, the village-building project should secure independent financial resources. In other words, there is an excuse to seek ways to continuously secure independent funds without relying on the administration financially for the village development project. Third, village-building should be carried out in phases. The government should support the activities of residents and promote continuous projects through phased project implementation. Fourth, a foundation must be laid for the universities and specialized high schools in the community to operate programs for regional innovation, such as social innovation.

• Journal of Distribution Science
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• v.11 no.8
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• pp.5-14
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• 2013

Purpose - We live in a world of constant change and competition. Many airports have specific competitiveness goals and strategies for achieving and maintaining them. The global economic recession, financial crises, and rising oil prices have resulted in an increasingly important role for facility investment and renewal and the implementation of appropriate policies in ensuring the competitive advantage for airports. It is thus important to analyze the factors that enhance efficiency and productivity for an airport. This study aims to determine the efficiency levels of 20 major airports in East Asia, Europe, and North America. Further, this study also suggests suitable policies and strategies for their development. Research design, data, and methodology - This paper employs the DEA-CCR, DEA-BCC, and DEA-Malmquist production index analysis models to determine airport efficiency. The study uses data on the efficiency and productivity of the world's leading airports between 2006 and 2010. The input variables include the airport size, the number of runways, the size of passenger terminals, and the size of cargo terminals. The output variables include the annual number of passengers and the annual cargo volume. The study uses basic data from the 2010 World Airport Traffic Report (ACI). The world's top 20 airports (as rated by the ACI report) are investigated. The study uses the expanded DEA Model and the Super Efficiency Model to identify the most effective airports among the top 20. The Malmquist productivity index analysis is used to measure airport effectiveness. Results - This study analyzes longitudinal and cross-sectional data on the world's top 20 airports covering 2006 to 2010. A CCR analysis shows that the most efficient airports in 2010 were Gatwick Airport (LGW), Zurich Airport (ZRH), Vienna Airport (VIE), Leonardo da Vinci Fiumicino Airport (FCO), Los Angeles International Airport (LAX), Seattle-Tacoma Airport (SEA), San Francisco Airport (SFO), HongKong Airport (HKG), Beijing Capital International Airport (PEK), and Shanghai Pudong Airport (PVG). We find that changes in airport productivity are affected more by technical factors than by airport efficiency. Conclusions - Based on the study results, we offer four airport development proposals. First, a benchmark airport needs to be identified. Second, inefficiency must be reduced and high-cost factors need to be managed. Third, airport operations should be enhanced through technical innovation. Finally, scientific demand forecasting and facility preparation must become the focus of attention. This paper has some limitations. Because the Malmquist productivity index is based on the hypothesis of the, the identified production change could be over- or under-estimated. Further, as DEA estimates the relative efficiency. It also cannot generalize to include all airport conditions because the variables are limited. To measure airport productivity more accurately, other input variables and environmental variables such as financial and policy factors should be included.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.3
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• pp.31-38
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• 2010

The purpose of this study is to evaluate the seismic performance of gravity-designed post tensioned (PT) flat plate frames with and without slab bottom reinforcement passing through the column. In low and moderate seismic regions, buildings are often designed considering only gravity loads. This study focuses on the seismic performance of gravity load designed PT flat plate frames. For this purpose, 3-, 6- and 9-story PT flat plate frames are designed considering only gravity loads. For reinforced concrete flat plate frames, continuous slab bottom reinforcement (integrity reinforcement) passing through the column should be placed to prevent progressive collapse; however, for the PT flat plate frames, the slab bottom reinforcement is often omitted since the requirement for the slab bottom reinforcement for PT flat plates is not clearly specified in ACI 318-08. This study evaluates the seismic performance of the model frames, which was evaluated by conducting nonlinear time history analyses. For conducting nonlinear time history analyses, six sets of ground motions are used as input ground motions, which represent two different hazard levels (return periods of 475 and 2475 years) and three different locations (Boston, Seattle, and L.A.). This study shows that gravity designed PT flat plate frames have some seismic resistance. In addition, the seismic performance of PT flat plate frames is significantly improved by the placement of slab bottom reinforcement passing through the column.