• Journal of Korean Institute of Industrial Engineers
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• v.24 no.3
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• pp.457-473
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• 1998

As a product structure or BOM(bill of material) of products is hierarchically structured, the design based on the concept of relational data base modeling causes low performances in data search or processing. For this reason, an object-oriented approach to designing a product structure is proposed in this paper. Using Rumbaugh's OMT (Object Modeling Technique) method, classes of parts, BOM structure, options, and models are defined and their class-relationship diagrams are proposed. For the representation of the BOM structure suitable for the object-oriented paradigm, a new data architecture called the BOM item class is suggested. It is expected that the proposed data structure ensures better reusability and expandability due to the modularity.

• Journal of the Korean Geographical Society
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• v.28 no.4
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• pp.356-378
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• 1993

This study examines the competitiveness of urban industrial structure and its changing characteristics. Cluster analysis of Arizona towns based on economic functions revealed the changing characteristics of urban functions over time. The relationship between the changes of urban functions and industrial competitiveness was confirmed through shift-share analysis. The level of industrial specialization has become more closely related to urban size in terms of both population and employment, but the relationship between metropolitan location and specialization level is not clear. Also, it is validated that the economies of Arizona towns have become more diversified and, consequently, have tended to converge toward the state average in industrial structure over time.

• Mycobiology
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• v.49 no.4
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• pp.376-384
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• 2021

Agaricus bisporus is a popular edible mushroom that is cultivated worldwide. Due to its secondary homothallic nature, cultivated A. bisporus strains have low genetic diversity, and breeding novel strains is challenging. The aim of this study was to investigate the genetic diversity and population structure of globally collected A. bisporus strains using simple sequence repeat (SSR) markers. Agaricus bisporus strains were divided based on genetic distance-based groups and model-based subpopulations. The major allele frequency (MAF), number of genotypes (NG), number of alleles (NA), observed heterozygosity (HO), expected heterozygosity (HE), and polymorphic information content (PIC) were calculated, and genetic distance, population structure, genetic differentiation, and Hardy-Weinberg equilibrium (HWE) were assessed. Strains were divided into two groups by distance-based analysis and into three subpopulations by model-based analysis. Strains in subpopulations POP A and POP B were included in Group I, and strains in subpopulation POP C were included in Group II. Genetic differentiation between strains was 99%. Marker AB-gSSR-1057 in Group II and subpopulation POP C was confirmed to be in HWE. These results will enhance A. bisporus breeding programs and support the protection of genetic resources.

• Journal of Korean Society for Quality Management
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• v.23 no.1
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• pp.95-105
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• 1995

The error structure of nonlinearized technological growth models, such as, the Pearl curve, the Gompertz curve and the Wei bull growth curve, has zero mean and a constant variance over time. Transformed models, however, like the linearized Fisher-Pry model. the linearized Gompertz growth curve, and the linearized Weibull growth curve have increasing variance from t = 0 to the inflection point.

• Journal of Korean Institute of Industrial Engineers
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• v.22 no.2
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• pp.277-302
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• 1996

The overall performance of BISDN depends significantly on the interconnection network or the switch fabric. Hence, it is extremely important to evaluate the performance of the network or the fabric. The well developed performance models also provide insight into the factors that determine design tradeoffs as well as quantitative estimates of their importance. The objective of this paper is to investigate and critically compare all the developed performance analysis models of FPS according to internal switch fabric structure, traffic assumptions, performance measures, methodologies, etc. FPSs are described according to their internal fabric structure. Brief history of FPS performance analysis is mentioned and performance analysis modeling is discussed.

• Journal of Industrial Technology
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• v.31 no.A
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• pp.27-31
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• 2011

In many industrial experiments, some practical constraints often force factors in an experiment to be much harder to change than others. Such an experiment involves randomization restrictions and it can be thought of as split-plot experiment. This paper investigates the path of steepest ascent/descent within a split-plot structure. A method is proposed for calculating the coordinates along the path.

• Journal of Labour Economics
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• v.35 no.1
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• pp.55-88
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• 2012

This article investigates the patterns of workforce aging in each industry, and examines how changing industrial structure affected the labor-market demand for and employment security of older workers in Korea. The relative size of the industries that are major employers of older workers has relatively declined since 2001, resulting in a decrease in labor-market demand for aged persons. Changes in industrial structure that occurred during the last decade have also brought an overall deterioration in the extent of employment security of older workers. These results suggest that the economic environment surrounding policies aimed at encouraging the employment of older workers is not entirely favorable. This paper also points out that policy makers need to consider that employment conditions of older workers are highly heterogenous across industries.

• Industrial Engineering and Management Systems
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• v.10 no.2
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• pp.161-169
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• 2011

In seeking further efficiency in production preparation, it is common to examine assembly sequences using digital manufacturing. The assembly sequences affect the product evaluation, so it is necessary to test several assembly sequences before actual production. However, because selection and testing of assembly sequences depends on the operator's personal experience and intuition, only a small number of assembly sequences are actually tested. Nevertheless, there is a systematic method for generating assembly sequences using a contact-related figure. However, the larger the number of parts, the larger the number of assembly sequences geometric becomes. The purpose of this study is to establish a systematic method of generating efficient assembly sequences regardless of the number of parts. To generate such assembly sequences selectively, a "Tournament Tree," which shows the structure of an assembly sequence, is formulated. Applying the method to assembly sequences of a water valve, good assembly sequences with the same structure as the Tournament Tree are identified. The structure of such a Tournament Tree tends to have fewer steps than the others. As a test, the structure is then applied for a drum cartridge with 38 parts. In all the assembly sequences generated from the contact-related figures, the best assembly sequence is generated by using the Tournament Tree.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.295-301
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• 2000

Various nondestructive prospecting method were applied to detect the flaws of concrete structure, but the satisfactory result could not be obtained, yet. Fracture and cavities existing concrete structure will have a bad effect on physical and mechanical characteristic of concrete. This study deal with detection of flaws using seismic first arrival and various inversion method in theoretical model. And ultrasonic seismic method is tried to experimental model to detect fracture and cavity.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.153-160
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• 2007

In this paper, the exact analysis of the parallel coupled line with open stub is presented. This structure shows LPF characteristics with broad stopband and sharp skirt characteristics. We derived the exact Z-matrix expression of the structure. In order to show the validation of the expression we designed $3^{th}$ order Chebyshev LPF using the structure. The simulated data excellently agreed with the predicted values by the calculation using the derived expression.