• International Journal of Reliability and Applications
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• v.4 no.4
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• pp.191-199
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• 2003

In the present work, a moment inequality is derived for new renewal better (worse) than used in expectation(NRBUE) (NRWUE) distributions. This inequality demonstrates that if the mean life is finite then all higher order moments exist. A new test statistics for testing exponentiality against NRBUE (NRWUE) is introduced based on this inequality. It is shown that the proposed test is simple and has high relative efficiency for some commonly used alternatives. Critical values are tabulated for sample sizes n = 5(1)30. A set of real data is used as an example to elucidate the use of the proposed test statistics for practical reliability analysis.

• Journal of radiological science and technology
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• v.25 no.1
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• pp.63-71
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• 2002

The aim of this study Is to develop a simple and fast method which computes in-vivo doses from transmission doses measured doting patient treatment using an ionization chamber. Energy fluence and the dose that reach the chamber positioned behind the patient is modified by three factors: patient attenuation, inverse square attenuation. and scattering. We adopted a straightforward empirical approach using a phantom transmission factor (PTF) which accounts for the contribution from all three factors. It was done as follows. First of all, the phantom transmission factor was measured as a simple ratio of the chamber reading measured with and without a homogeneous phantom in the radiation beam according to various field sizes($r_p$), phantom to chamber distance($d_g$) and phantom thickness($T_p$). Secondly, we used the concept of effective field to the cases with inhomogeneous phantom (patients) and irregular fields. The effective field size is calculated by finding the field size that produces the same value of PTF to that for the irregular field and/or inhomogeneous phantom. The hypothesis is that the presence of inhomogeneity and irregular field can be accommodated to a certain extent by altering the field size. Thirdly, the center dose at the prescription depth can be computed using the new TMR($r_{p,eff}$) and Sp($r_{p,eff}$) from the effective field size. After that, when TMR(d, $r_{p,eff}$) and SP($r_{p,eff}$) are acquired. the tumor dose is as follows. $$D_{center}=D_t/PTF(d_g,\;T_p){\times}(\frac{SCD}{SAD})^2{\times}BSF(r_o){\times}S_p(r_{p,eff}){\times}TMR(d,\;r_{p,eff})$$ To make certain the accuracy of this method, we checked the accuracy for the following four cases; in cases of regular or irregular field size, inhomogeneous material included, any errors made and clinical situation. The errors were within 2.3% for regular field size, 3.0% irregular field size, 2.4% when inhomogeneous material was included in the phantom, 3.8% for 6 MV when the error was made purposely, 4.7% for 10 MV and 1.8% for the measurement of a patient in clinic. It is considered that this methode can make the quality control for dose at the time of radiation therapy because it is non-invasive that makes possible to measure the doses whenever a patient is given a therapy as well as eliminates the problem for entrance or exit dose measurement.

• The Journal of Industrial Distribution & Business
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• v.10 no.8
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• pp.55-65
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• 2019

Purpose - Recently, the fourth industrial revolution is rapidly progressing, and the central government-led innovation system is not able to flexibly cope with changes in science and the economy and society. To solve these problems, it is necessary for local governments, which can easily identify and flexibly respond to local sites, to become self-centered and ready to respond more quickly to massive changes. Through this research, this study investigated the awareness of the elements of Jeonnam Province's capabilities in the field of science and technology policy, the importance of R&D, and how network cooperation among the base institutions might affect performance. Research design, data, and methodology - In fact, the data used in this study only 115 people were polled, excluding five who did not respond to the necessary variables. The methods of the survey were sampled, and the means of the survey were investigated via a self-contained electronic file (e-mail). Statistical analysis, including hypothesis verification, was performed by SPSS 19. The regression analysis was used. Results - All factors significantly affect performance by dividing them into five sub-fields: R&D strategic establishment, R&D demand survey, R&D planning, R&D evaluation, and R&D project management. These results suggest the importance and need for local scientific technology policy capabilities. Besides, it was confirmed that the relationship between regional science and technology policy capabilities and performance was moderated by the recognition of the importance of science technology and network cooperation among the core organizations. Conclusions - As a result, independent variables regarding the capabilities of each scientific technology policy were found to be statistically significant and have a significant effect on performance. Second, the regression analysis has shown the moderation effects of R&D importance awareness between the capabilities of science and technology policies and their performance. On the other hand, a regression analysis showing that the capabilities of science and technology policies and network cooperation between the base regions were not significant, indicating that there is no effect of moderation of network cooperation between the base regions between the capabilities of science and technology policies and performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6587-6598
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• 2014

This study tested the hypothesis from the previous research issues and empirically investigated the determinants of cooperative strategy for technological innovation, using the multinomial logit model. The meaningful conclusions from this study are as follows. First, the characteristics of the company and product are not the significant determinants for cooperative strategy for technological innovation. Second, formal R&D organization characteristics are significant factors in determining the type of cooperative strategy for technological innovation. Third, the support of government is a significant determinant and if a company receives more government support, it is likely to accept public type cooperation. Fourth, the characteristics of industry are significant determinants and if a company belongs to a higher technology industry, it is likely to accept vertical type cooperation with private enterprises. This study analyzed the hypotheses raised in a variety of studies empirically. This paper presents the basis of various studies concerning technological cooperation strategies.

• Animal cells and systems
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• v.6 no.1
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• pp.13-18
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• 2002

Phylogenetic relationships of Korean Acidiella species were tested using mitochondrial 16S ribosomal RNA gene sequences. We used 16 published sequences as outgroup, and 10 new sequences for nine Korean Acidiella species as ingroup. The number of aligned sites was 1,281 bp, but 1,135 bp were used for the analysis after excluding sites with missing data or gaps. Among these 1,135 sites, 464 sites were variable and 340 were informative for parsimony analysis. Phylogenetic information was extracted from this data set using neighbor-joining, maximum likelihood and maximum parsimony methods and compared to a morphology-based phylogenetic hypothesis. Our molecular data suggest that: (1) the tribe Trypetini appears to be monophyletic even when the nine additional Acidiella species are added to our previous phylogenetic analysis; (2) all the Korean Acidiella species belong to the Trypeta group, but the genus Acidiella is not supported as monophyletic; (3) the close relationship of A. circumvaga, A. issikii, and A. sapporensis is supported; (4) the close relationship of A. pachypogon and two additional new Acidiella species is strongly supported; and (5) the possible presence of two or more cryptic species among the specimens previously identified as A. obscuripennis is suggested. Sequence data from the mitochondrial 16S rDNA allowed us to better understand the systematic status of Korean Acidiella species. They indicated that the current concept about the genus Acidiella is insufficient and needs to be refined further. This study also showed a few interesting relationships, that had not been recognized by morphological study alone. Based on this study, we were able to plan further experiments to analyze relationships within the Trypeta Group.

• The Korean Journal of Applied Statistics
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• v.24 no.5
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• pp.883-891
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• 2011

For survival data we sometimes want to test a log normality hypothesis that can be changed into normality by transforming the survival data. Hence the Shapiro-Wilk type statistic for normality is generalized to randomly censored data based on the Kaplan-Meier product limit estimate of the distribution function. Koziol and Green (1976) derived Cram$\acute{e}$r-von Mises statistic's randomly censored version under the simpl hypothesis. These two test statistics are compared through a simulation study. As for the distribution of censoring variables, we consider Koziol and Green (1976)'s model and other similar models. Through the simulation results, we can see that the power of the proposed statistic is higher than that of Koziol-Green statistic and that the proportion of the censored observations (rather than the distribution of censoring variables) has a strong influence on the power of the proposed statistic.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.15-21
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• 2014

The long memory properties of the hedge ratio for stock and futures have not been systematically investigated by the extant literature. To investigate hedge ratio' long memory, this paper employs a data set including KOSPI200 and S&P500. Coakley, Dollery, and Kellard(2008) employ a data set including a stock index and commodities foreign exchange, and suggested the S&P500 to be a fractionally integrated process. This paper firstly estimates hedge ratios with two dynamic models, BEKK(Bollerslev, Engle, Kroner, and Kraft) and diagonal-BEKK, and tests the long memory of hedge ratios with Geweke and Porter-Hudak(1983)(henceforth GPH) and Lo's modified rescaled adjusted range test by Lo(1991). In empirical results, two hedge ratios based on KOSPI200 and S&P500 show considerably significant long memory behaviours. Thus, such results show the hedge ratios to be stationary and strongly reject the random walk hypothesis on hedge ratios, which violates the efficient market hypothesis.

• The Korean Journal of Rehabilitation Nursing
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• v.2 no.1
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• pp.61-71
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• 1999

This quasi-experimental study was intended to test the effect of self-help group program, which is one of the way to enhance adaptation and quality of life to mastectomy patients. Data was collected from July 14, 1998 to Oct. 31, 1998 at two Medical Center in Seoul. The subjects for this study were the patients who had undergone mastectomy and were follow-up ; 14 in experimental group and 14 in control group matched with age and treatment. The instruments for this study were adaptation in Lee(1994)'s physical symptom questionnaire, Zung's Self-rating Depression Scale(SDS, 1965), and Self-rating Anxiety Scale(SAS, 1970), quality of life in Spranger(1996)'s and No(1988)'s Quality of Life Questionnaire. The self-help group program for mastectomy patients was developed based on literature review and pilot study by the investigator. The subjects of experimental group were participated in 6 weeks self-help group program and were received arm and shoulder exercise, informational support, and interpersonal support by group members. The control group were received no intervention, Both group answered questionnaires prior to intervention and 6 weeks later. The data analyzed by frequency, $X^2$-test, Mann-Whitney U test. Wilcoxon Signed Rank test, Pearson's Correlation Coefficient and Stepwise Multiple Regression using SPSS WIN. The results are as follows ; Hypothesis 1. "The experimental group with the self-help group program will have a higher score on adaptation state than control group." was not supported. But the post test score of anxiety and depression in experimental group were declined and the depression score was reduced relatively. Hypothesis 2. "The experimental group with the self-help group program will have a higher score on quality of life than control group." was not supported. But the posttest score of quality of life in experimental group was reduced relatively. Hypothesis 3. "The higher adaptation state of mastectomy patients, the higher quality, of life." was supported(r=,80, p<.001). Additionally, the lower physical symptom, depression and anxiety, the higher quality of life And depression, which was the main predictor of quality of life, accounted for 59.5%, depression and anxiety accounted for 65.5% of the variance in quality of life. In conclusion, when the self-help group program was intervened to mastectomy patients, it was tended to increase quality of life and to reduce depression and anxiety. So self-help group program can be considered useful nursing inter vention effect on adaptation and quality of life of mastectomy patients. With discussion, I suggest repeated further re search on self-help group with appropriate sample size and longitudinal study. Also during adjuvant therapy, it is needed to develop convenient method to be supported from peer group and family, such as computer mediated support group.

• Journal of Acupuncture Research
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• v.18 no.4
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• pp.46-54
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• 2001

Objective : To study correlation of the brain areas with acupoints used in the treatment of cerebrovascular diseases to evaluate the hypothesis that selecting acupoints on the left side to treat disorders on the right side and vice versa is known as the crossing combination of acupoints. Materials and Methods: Rest/acupuncture-stimulation Tc-99m ECD brain SPECT using a same-dose subtraction method was performed on 5 normal male volunteers (age range from 27 to 30 years) using acupuncture at acupoint, LI4 located in the left hand. In the control study, needle location was chosen on a non-meridian focus 1cm posterior to the right fibular head. All images were spatially normalized and the differences between rest and acupuncture stimulation were statistically analyzed using SPM(R) for Windows(R). Results : Acupuncture applied at LI4 located in the left hand increased rCBF in the right hemisphere, that is, the right parietal lobe(angular gyrus) and a part of the right middle posterior temporal gyrus and the right inferior occipital lobe. In the control stimulation, no significant rCBF increase was observed. Conclusion : The results demonstrated a correlation between stimulation at acupoint with increase in rCBF to the controlateral hemisphere.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1024-1030
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• 2006

Genus Nitrospira and Nitrobacter species are the key nitrite-oxidizing bacteria(NOB) in nitrifying wastewater treatment plants. It has been hypothesized that genus Nitrospira are K-strategists(low $K_6$ value) that can exploit low amounts of nitrite more efficiently than Nitrobacter. In contrast, Nitrobacter species are r-strategists(high $V_{max}$) that can grow faster than Nitrospira. It has also been known that the availability of organic compounds and dissolved oxygen as well as nitrite affects the distribution of NOB. In this study, we determined the distribution and competition of NOB in wastewater nitrification systems where nitrite, organic compounds, and dissolved oxygen concentrations were compositively varied. For the purpose, several compounds of the laboratory-scale nitrificaiion bioreactor and full-scale $A_2O$ wastewater treatment plant and their distribution of NOB were analyzed and compared. The analysis showed that Nitrobacter was the dominant NOB in nitrification bioreactor where average nitrite was maintained at 5 mg-N/L with very low organic concentration in aerobic condition, whereas Nitrospira was the dominant NOB in full-scale $A_2O$ plant where nitrite was maintained very low and organic compounds were maintained relatively high in alternating aerobic-anoxic condition. The result indicates that nitrite concentration is more critical factor than organics and dissolved oxygen which determines the dominant NOB in nitrification system and it is confirmed that Nitrospira and Nitrobacter showed the characteristics of r-strategist and K-strategist, respectively.