• Journal of applied mathematics & informatics
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• v.41 no.2
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• pp.449-468
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• 2023

This paper deals in the study of the estimation of the parameters of Erlang distribution based on rank set sampling and some of its modifications. Here we considered Maximum Likelihood (ML) and the Bayesian technique to estimate the shape and scale parameter of Erlang distribution based on RSS and its some modifications such as ERSS, MRSS, and MRSSu. The derivation for unknown parameters of Erlang distribution is well presented using normal approximation to the asymptotic distribution of ML estimators. But due to the complexity involves in the integral, the Bayes estimator of unknown parameters is obtained using MCMC method. Further, we compared the MSE of estimation in different sampling schemes with different set sizes and cycle size. A real-life data application is also given to illustrate the efficiency of the proposed scheme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1679-1684
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• 2009

Opuntia humifusa, widely distributed in the southern regions of the Korean peninsula, is known to have bioactive functions and medicinal benefits for treating various diseases such as arteriosclerosis, diabetes mellitus, gastritis, and hyperglycemia. In this study total polyphenol and flavonoid contents of fruit and its anticarcinogenic effects on human breast cancer were investigated. As expected, O. humifusa showed high concentrations of total polyphenol as well as flavonoid as compared to other kinds of cactus. Effects of the water extracts of O. humifusa on the proliferation, G1 arrest and apoptosis of the MCF-7 human breast cancer cells were also examined using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays, and G1 cycle arrest and apoptotic effect of O. humifusa were analyzed by flow cytometry. When MCF-7 cells were treated with different concentrations of hexane, ethyl acetate and water extracts of O. humifusa, water extracts of the fruit significantly decreased viable cell numbers in a concentration dependent manner. A G1 arrest in MCF-7 cells was induced as well. The overall results indicate that water extracts of fruit of O. humifusa would inhibit MCF-7 human breast cancer cell proliferation and induce G1 arrest.

• Journal of Life Science
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• v.13 no.1
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• pp.42-46
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• 2003

Photoplethysmogram is widely used to measure heart rate and arterial blood oxygen saturation in human. This paper describes radial pulse waves recorded by photoplethysmogram with 940 nm wavelength infra red light. Radial pulse waves were varied according to the recording site. When recorded on the skin over radial artery, the radial pulse wave was inverted, comparing to the photoplethysmogram at fingertip. The mechanism of inverted pulse wave seemed to be caused by the change of the blood volume in the subcutaneous tissue between radial artery and the skin, which was reduced during systolic period and increased during diastolic period of the cardiac cycle. These results suggest that radial arterial wall may reflect infra red ray.

• Korean Journal of Computational Design and Engineering
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• v.21 no.2
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• pp.111-121
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• 2016

The plant equipment usually has a long life cycle. During its O&M (Operation & Maintenance) phase, since the occurrence of an accident of offshore plant equipment causes catastrophic damage, it is necessary to make more efforts for managing critical offshore equipment. Nowadays due to the emerging ICTs (Information Communication Technologies) and sensor technologies, it is possible to gather the health status data of important offshore equipment and their environment data, which leads to much concern on CBM (Condition-Based Maintenance). In this study, we will propose an approach to estimate the remaining lifetime of an offshore plant equipment (pump tower) based on gathered ocean environment data.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.2
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• pp.233-245
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• 2010

This paper proposes security architecture, security audit framework, and audit check item. These are based on the security requirement that has been researched in the information system audit. The proposed information security architecture is built in a way that it could defend a cyber attack. According to its life cycle, it considers a security service and security control that is required by the information system. It is mapped in a way that it can control the security technology and security environment. As a result, an audit framework of the information system is presented based on the security requirement and security architecture. The standard checkpoints of security audit are of the highest level. It was applied to the system introduction for the next generation of D stock and D life insurance company. Also, it was applied to the human resources information system of K institution and was verified. Before applying to institutions, system developers and administrators were educated about their awareness about security so that they can follow guidelines of a developer security. As a result, the systemic security problems were decreased by more than eighty percent.

• 한국IT서비스학회:학술대회논문집
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• 2009.05a
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• pp.415-427
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• 2009

Diffusion of information technology such as internet has brought a great influence on modern society and industrial development. Currently wide-spread RFID/USN technology has become a central momentum of this rapid changes for the establishment of ubiquitous society in the future. Historically agricultural products has drawn research interest due to its importance of human life. A standard monitoring system throughout of life cycle of the agricultural products should be developed and careful monitoring process should be introduced. In this paper, by way of case study, current lifetime tracing systems are evaluated and critical drawbacks and issues are also developed. In addition, some implications and guidelines to improve the tracing performance of the products are also suggested.

• Fashion & Textile Research Journal
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• v.23 no.2
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• pp.174-185
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• 2021

The purpose of the study is to establish sustainability evaluation items that can be applied to enhance clothing sustainability practice. The sustainability evaluation items related to clothing by product category, use, and disposal were derived through literature review. In order to evaluate the validity of the derived evaluation items, preliminary survey and two questionnaires were conducted for experts, and the importance and the possibility of change were measured. As a result, 39 evaluation items were constructed. Among the 39 evaluation items, 26 items related to the use and disposal were evaluated for 10 weeks in the 20s and 30s female consumers in terms of practice. The results of the study are as follows: First, items that have a high degree of importance and possibility of change are the items that can minimize resource saving, recycling, and the emission of harmful substances. Second, the participants' perceptions, attitudes, and outcomes of practicing the evaluation items of the use and disposal phase were proved to be positively affected, and the possibility of reducing resource saving and environmental impacts was proved. The clothing sustainability practice played a positive and developmental role in real life, while changing from small things to pursuing newness. The vagueness of sustainability was changed to specific perceptions and behaviors through the practice of the evaluation items.

• Journal of Life Science
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• v.17 no.12
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• pp.1709-1716
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• 2007

The health benefits of garlic (Allium sativum L.) are derived from a wide variety of components and from the different ways it is administered. The known health benefits of garlic include cardiovascular protective effects, stimulation of immune function, reduction of blood glucose level, protection against microbial, viral and fungal infections, as well as anticancer effects. In the present study, it was examined the effects of water extract of A. sativum (WEAS) on the growth of cultured human tumor cells in order to investigate its anti-proliferative mechanism. Treatment of WEAS to tumor cells resulted in the growth inhibition, especially in leukemia cells, which was associated with induction of G2/M arrest of the cell cycle and apoptosis. In order to further explore the critical events leading to apoptosis in WEAS-treated U937 human leukemia cells, the following effects of WEAS on components of the mitochondrial apoptotic pathway were examined: generation of reactive oxygen species (ROS), alteration of the mitochondrial membrane potential (MMP), and the expression changes of Bcl-2 and IAP family proteins. The cytotoxic effect of WEAS was mediated by its induction of apoptosis as characterized by the occurrence of DNA ladders, apoptotic bodies and chromosome condensation in U937 cells. The WEAS-induced apoptosis in U937 cells was correlated with the generation of intracellular ROS, collapse of MMP, activation of caspase-3 and down-regulation of anti-apoptotic proteins. The quenching of ROS generation with antioxidant N-acetyl-L-cysteine conferred significant protection against WEAS-elicited ROS generation, caspase-3 activation, G2/M arrest and apoptosis. In conclusion, the present study reveals that the cellular ROS generation plays a pivotal role in the initiation of WEAS-triggered apoptotic death in U937 cells.

• Journal of Mechanical Science and Technology
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• v.17 no.6
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• pp.825-835
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• 2003

Previous studies have demonstrated the importance of joint angle errors mainly due to skin artifact and measurement errors during gait analysis. Joint angle errors lead to unreliable kinematics and kinetic analyses in the investigation of human motion. The purpose of this paper is to present the Joint Averaging Coordinate System (JACS) method for human gait analysis. The JACS method is based on the concept of statistical data reduction of anatomically referenced marker data. Since markers are not attached to rigid bodies, different marker combinations lead to slightly different predictions of joint angles. These different combinations can be averaged in order to provide a "best" estimate of joint angle. Results of a gait analysis are presented using clinically meaningful terminology to provide better communication with clinical personal. In order to verify the developed JACS method, a simple three-dimensional knee joint contact model was developed, employing an absolute coordinate system without using any kinematics constraint in which thigh and shank segments can be derived independently. In the experimental data recovery, the separation and penetration distance of the knee joint is supposed to be zero during one gait cycle if there are no errors in the experimental data. Using the JACS method, the separation and penetration error was reduced compared to well-developed existing methods such as ACRS and Spoor & Veldpaus method. The separation and penetration distance ranged up to 15 mm and 12 mm using the Spoor & Veldpaus and ACRS method, respectively, compared to 9 mm using JACS method. Statistical methods like the JACS can be applied in conjunction with existing techniques that reduce systematic errors in marker location, leading to an improved assessment of human gait.

• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.123-130
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• 1995

Many types of medication regimens have been used for controlled ovarian hyperstimulation for assisted reproductive technique(ART). Questions are now being raised regarding how to lower the escalating costs of assisted reproduction and decrease the extent of patient discomfort and disruption of life style without sacrificing success rates. In this investigation, from January 1994 through August 1994 patients presenting to the Chung-Ang university hospital, infertility clinic were offered the option of the clomiphene citrate (CC)/single Human Menopausal Gonadotropin(HMG) combination and conventional GnRH-agonist combination method. 60 patients (78 cycles) were given CC/single HMG combination as a study group, and 78 patients (102 cycles) were given conventional GnRH-a combined ultrashort protocol as a control group for IVF-ET program and the resulting number of oocyte retrieved, embryo produced, and pregnancy initiated were compared. There were no differences between the two groups in mean age, serum $E_2$, LH and FSH level on menstrual cycle day 2. HMG requirement was 2 ampules in study group and $24.2{\pm}6.8$ ampules in control group. On the day of HCG injection, serum LH and FSH levels were not significantly different, but serum $E_2$, was significantly higher in control group(p<0.001). There was relatively well endometrial quality in control group but not significant compare to study group. In control group, numbers of retrieved oocyte and transferred embryo were significantly more than study group(p<0.001). Fertilization rate was not significantly different in the two groups and pregnancy rates were 20.2% in study group 28.4% in control group(p<0.001). CC/single HMG protocol for IVF-ET is less expensive than GnRH-a combined ultrashort protocol and minimizes patients discomfort. In addition, CC/single HMG protocol produces acceptable pregnancy rate and represents an attractive alternative to select patients undergoing IVF-ET.