• The Korea Journal of Herbology
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• v.23 no.1
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• pp.109-116
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• 2008

Objectives : This study was performed to investigate the discriminative criteria of 6 kinds of Achyranthis Radix by HPLC/DAD. Methods : 20-hydroxyecdysone is isolated by silica gel column chromatography ($CHCl_3$:MeOH, 7:1-1:1 v/v) and identified by nuclear magnetic resonance, A high-performance liquid chromatographic method with diode array detection was used to identify 20-hydroxyecdysone in A. japonica. The analysis was performed using $C_{18}$ column with isocratic elution consisted of 18% acetonitrile and 82% water and the detection was carried out by DAD at 254 nm. 6 kinds of Achyranthis Radix from different locations were extracted in MeOH. Each extracts was analyzed by HPLC in same condition as used in analysis of 20-hydroxyecdysone. The identities of each extracts were determined by comparing the retention time and UV spectrum with that of reference compound. Results : 1. A. japonica and A. bidentata showed the similar patterns of HPLC chromatogram and 20-hydroxycedysone was present in both of them because the peaks having the same retention time and UV spectrum as 20-hydroxyecdysone were shown in the HPLC chromatograms of A. japonica and A. bidentata 2. Cyathula officinalis and C. capitata showed the similar patterns of HPLC chromatogram. The peak having the same retention time and UV spectrum as 20-hydroxyecdysone was shown in the HPLC chromatogram of C. capitata but not shown in the HPLC chromatogram of C. officinalis. 3. Two species of medicinal drugs from Sacheon province showed similar patterns of HPLC chromatogram. Achyranthis Radix from Sacheon(wild) did not have 20-hydroxycedysone but Achyranthis Radix from Sacheon(cultivated) showed the peak having the same retention time as 20-hydroxyecdysone but UV spectrum of the peak was different from that of 20-hydroxyecdysone. Conclusions : These results suggested that 20-hydroxyecdysone could be the discriminative criteria for Achyranthis Radix contain 20-hydroxyecdysone though they belong to different genus and species. And the patterns of HPLC chromatogram also could be the discriminative criteria as the different species of Achyranthis Radix belonging to the same genus showed similar patterns of HPLC chromatogram.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.117-125
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• 2003

Experimental and theoretical works were performed for the separation of large polyelectrolyte, such as DNA, in a column packed with gel particles under the influence of an electric field. Since DNA quickly orient in the field direction through the pores, this paper presents how intraparticle convection affects the residence time distribution of DNAs in the column. The concept is further illustrated with examples from solid -liquid systems, for example, from chromatography Showing how the column efficiency is improved by the use of a n electric field. Dimensionless transient mass balance equations were derived, taking into consideration both diffusion and electrophoretic convection. The separation criteria are theoretically studied using two different Peclet numbers in the fluid and solid phases. These criteria were experimentally verified using two different DNAs via electrophoretic mobility measurements. which showed how the separation position of the DNAs varies in the column in relation to the Peg/Pef values of an individual DNA. The residence time distribution was solved by an operator theory and the characteristic method to yield the column response.

• Steel and Composite Structures
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• v.3 no.4
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• pp.231-242
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• 2003

This paper deals with the formulation and development of fracture criteria for high-strength structural members containing surface damage in the form of notches (i.e., blunt defects). The important role of the yield strength of the material and its strain hardening capacity (evaluated by means of the constitutive law or stress-strain curve) is analysed in depth by considering the fracture performance of notched samples taken from high-strength steels with different levels of cold drawing (the most heavily drawn steel being commercial prestressing steel used in prestressed concrete). The final aim of the paper is to establish fracture-based design criteria for structural members made of steels with distinct yield strength and containing very different kinds of notch-shape surface damage.

• KIEAE Journal
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• v.10 no.3
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• pp.3-10
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• 2010

As indoor air quality directly affects health and comforts of the residents, researchers from different countries have continued to explore criteria by which indoor air quality can be indicated in a scientific and quantitative manner over the past several decades. However, there are many possibilities that can deteriorate indoor air quality. Due to the uncertainty of influence factors, it is quite difficult to develop a correct evaluation model and quantitative method. Furthermore, the effects from the indoor air pollutants have different levels, leading to the difficulties to apply the regular standard. This study aims to propose evaluation criteria by using the FD-AHP analysis. Obtained findings will be beneficial to construct apartment buildings, commercial buildings and others health performance evaluation framework.

• Journal of Communications and Networks
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• v.5 no.3
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• pp.197-201
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• 2003

We study in this paper both distributed power control and removal algorithms for multimedia CDMA wireless networks. In our study, users can have different data rates as well as different quality of service (QoS) requirements. We derive a necessary and sufficient condition for the fully distributed power control (FDPC) algorithm to find a feasible power set. We also prove that, if the maximal power level is used at the start, then the distributed constrained power control (DCPC) algorithm is equivalent to the FDPC algorithm. For the connection removal algorithm, we prove that the non-reinitialized removal algorithm finds a feasible power set faster and employs smaller power levels than the reinitialized one does. Performances of some connection removal criteria are also studied. Our simulation results reveal that the smallest normalized CIR (SNC) and largest CIR requirement (LCR) criteria result in smaller outage probability than the smallest CIR (SC) criterion in a multimedia environment.

• Communications for Statistical Applications and Methods
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• v.25 no.3
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• pp.307-319
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• 2018

High-throughput technologies enable the simultaneous evaluation of thousands of genes that could discriminate different subclasses of complex diseases. Ranking genes according to differential expression is an important screening step for follow-up analysis. Many statistical measures have been proposed for this purpose. A good ranked list should provide a stable rank (at least for top-ranked gene), and the top ranked genes should have a high power in differentiating different disease status. However, there is a lack of emphasis in the literature on ranking genes based on these two criteria simultaneously. To achieve the above two criteria simultaneously, we proposed to apply a previously reported metric, the modified area under the receiver operating characteristic cure, to gene ranking. The proposed ranking method is found to be promising in leading to a stable ranking list and good prediction performances of top ranked genes. The findings are illustrated through studies on both synthesized data and real microarray gene expression data. The proposed method is recommended for ranking genes or other biomarkers for high-dimensional omics studies.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.332-339
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• 2000

Experimental and theoretical works were performed for the separation of large polyelectrolytes such as DNA in the column packed with gel particles under an electric field. This paper shows how intraparticle convection effects the separation of DNAs in the column because DNAs quickly oriented through the pores in the field direction. Dimensionless transient mass balance equations were derived considering diffusion and electrophoretic convection. The separation criteria is theoretically studied using two different Peclet numbers in the fluid and solid phases and these criteria were verified uing two different DNAs by electrophoretic mobilities measured experimentally, showing how the separation position of DNAs varies in the column according to values of Pe(sub)f/Pe(sub)g of individual DNA. Governing equations are simultaneously solved by operator theoretic and characteristic methods to yield the column response.

• Industrial Engineering and Management Systems
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• v.14 no.4
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• pp.413-419
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• 2015

This study solved the problem of unstable production chains by considering allocation rate conformance. We proposed two phased algorithm suitable for solving production planning that considers allocation rate conformance; the first phase was heuristic initial solution generation, and the second phase was tabu-search based solution improvement. By using three data sets which have different sizes of data and three different criteria, the results of proposed algorithm were compared with MIP results. The proposed algorithm showed the best production plan in terms of allocation rate conformance, and it was appropriate for other criteria; it solved the problem of unstable production chains by solving concentrated and unfair allocation.

• The International Journal of Costume Culture
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• v.3 no.2
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• pp.147-160
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• 2000

The purposes of the present study were to investigate the factors of consumer dissatisfaction with backpacks and to examine if the levels of dissatisfaction with the factors differ significantly among the groups determined by demographic characteristics and purchase behaviors. The differences in the purchase behaviors of backpacks were also tested among the groups determined by demographic characteristics. Data collection was consisted of two pilot tests and the final test. The questionnaire was distributed to 40 students of universities in Seoul from July 1 to 13 in 2000 and 351 were usable. Data were analyzed by factor analysis, t-test, χ²analysis, MANOVA, ANAOVA, Duncan's multiple range tests using SPSS PC/sup +/ Program. Five factors were formulated : durability, ease-of-care/color fastness, dimensional stability, wearability and design. Subjects were most dissatisfied with the dimensional stability of backpacks. Different demographic characteristics and purchase behaviors resulted in significantly different levels of dissatisfaction with selected factors. Significant differences were also found in selected selection criteria and purchase behaviors among groups determined by some demographic characteristics.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.161-164
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• 2000

Currently, Atomic Force Microscope(AFM) has been widely used to measure the surface topography of a sample by detecting interaction force between atoms on the sample and extremely sharp probe tip. The vertical resolution of AFM is mainly determined by external vibration noise. The resolution of AFM shows different values for the different environment, thus it is necessary to determine relationship between the criteria and the resolution of AFM regardless of environment. In this paper, we discuss the allowable level of floor vibration for AFM equipment at given resolution. The vibration criteria can be used as reference data to design mechanical structure and to analyze the structural dynamics of AFM equipment.