Bong-Kuk Ko, Woo-Jung Lee and Jae-Hoon Lee
The purpose of this study is to understand what health and safety hazards low-income households are subject to by surveying the real conditions of the defective housing of…
Abstract
The purpose of this study is to understand what health and safety hazards low-income households are subject to by surveying the real conditions of the defective housing of low-income households, and to find improvement strategies. For this purpose, we visited the concentrated areas of the multi-dwelling unit (MDU) (also known as multi-family residential) housing in Jungwon-gu and Sujeong-gu in Seongnam City, Kyunggi-do, one of the representative areas in Korea with a massive distribution of the low-income class. Based on the survey data, the level of housing defects were comparison analyzed per income decile (decile 1, decile 2, deciles 3–4), and per housing location, in the categories of subsidence, cracks in the wall, delamination, water leakage/infiltration, condensation, and contamination. The housing condition per income class was more defective in the decile 2 households rather than in the decile 2 households, and in the substructure more than in the superstructure. Among the six defects, contamination problems, caused by sub-standard living conditions, were the most frequent cases. Structural defects, subsidence and cracks in the wall, were found in the main living areas—the bedrooms and the living rooms. It was confirmed in this study that the conditions of low-income housing are serious, and that it is necessary to explore specific countermeasures in the near future.
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Ji Hyun Cho, Jae Hoon Lee, Dong Geun Ahn and Joong Soon Jang
The purpose of this paper is to determine the key ingredients of Six Sigma in order to grasp and understand its essential characteristics and then identify suitable ingredients…
Abstract
Purpose
The purpose of this paper is to determine the key ingredients of Six Sigma in order to grasp and understand its essential characteristics and then identify suitable ingredients and complements in consideration of vision, strategies, capability, and circumstance of a company.
Design/methodology/approach
The study outlines the range of research in Korean enterprises, suppliers, and SMEs. Potential ingredients collected from previous studies about critical success factors, ingredients of Six Sigma and TQM, and criteria of quality awards (Malcolm Baldrige National Quality Award (MBNQA), European Foundation for Quality Management (EFQM) Award, Deming Prize, Korean National Quality Award) are classified into 11 categories based on Six Sigma expert opinions and affinity analysis. Also, questionnaires are surveyed from champions, master black belts and black belts in 90 Korean companies that have more than three years of experience in implementing Six Sigma. Statistical analysis with factor analysis and hypothesis testing has been done to select the key ingredients and to find the differences among the diverse types of companies.
Findings
By using factor analysis, three main factors are derived for each category respectively, and consequently 30 factors in 11 categories are concluded as the key ingredients of Six Sigma in Korean companies. There is a significant difference in importance of Six Sigma key ingredients according to company size, business type, and implementation phase.
Research limitations/implications
A study may be conducted to identify Six Sigma success factors according to corporate characteristics from key ingredients identified in this study in future.
Originality:/value
The paper investigates the key ingredients of Six Sigma based on a survey of diverse sizes, industries, and implementation phases of Korean companies. Compared with other studies conducted by empirical methods, the survey data are statistically analysed and the evaluation results are represented as quantitative indicators.
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Meanwhile, President Yoon Suk-yeol’s unpopular lame duck presidency has become more tenuous as prosecutors’ investigations continue into both Yoon and his wife, on one side, and…
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DOI: 10.1108/OXAN-DB291378
ISSN: 2633-304X
Keywords
Geographic
Topical
The ruling conservative People Power Party (PPP) will take scant consolation from avoiding an opposition supermajority, as it needed a win to take control of the assembly and…
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DOI: 10.1108/OXAN-DB286397
ISSN: 2633-304X
Keywords
Geographic
Topical
Yoonjung Choi, Jae Hoon Lim and Sohyun An
This study explores how recent Korean immigrant students experience learning social studies and how their unique social, cultural, and educational backgrounds as new immigrants…
Abstract
This study explores how recent Korean immigrant students experience learning social studies and how their unique social, cultural, and educational backgrounds as new immigrants shape their experiences in American schools. Based on survey and in-depth interviews with 43 Korean immigrant students in two urban and three suburban/rural areas, this mixed methods study examines Korean immigrant youths’ perceptions about the nature of history and social studies as well as their experiences of learning social studies in their everyday classroom contexts. Our data analysis demonstrates that Korean immigrant students face varying difficulties in constructing meaning in US history and engaging themselves in social studies learning, which results in a negative learning experience and subsequent disinterest in social studies. Researchers identified three major challenges that Korean immigrant youths experience in their social studies classrooms: (1) Lack of English proficiency, background knowledge, and American patriotism, (2) White, American-centered perspectives and marginalization of their country of origin, and (3) Teachers’ lack of care and disengaging pedagogies. The findings of this study provide implications for creating more meaningful and culturally relevant social studies learning for immigrant students.
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Chang-Hoon Sim, Han-Il Kim, Jae-Sang Park and Keejoo Lee
The purpose of this paper is to derive knockdown factor functions in terms of a shell thickness ratio (i.e. the ratio of radius to thickness) for conventional orthogrid and…
Abstract
Purpose
The purpose of this paper is to derive knockdown factor functions in terms of a shell thickness ratio (i.e. the ratio of radius to thickness) for conventional orthogrid and hybrid-grid stiffened cylinders for the lightweight design of space launch vehicles.
Design/methodology/approach
The shell knockdown factors of grid-stiffened cylinders under axial compressive loads are derived numerically considering various shell thickness ratios. Two grid systems using stiffeners – conventional orthogrid and hybrid-grid systems – are used for the grid-stiffened cylinders. The hybrid-grid stiffened cylinder uses major and minor stiffeners having two different cross-sectional areas. For modeling grid-stiffened cylinders with various thickness ratios, the effective thickness (teff) of the cylinders is kept constant, and the radius of the cylinder is varied. Thickness ratios of 100, 192 and 300 are considered for the orthogrid stiffened cylinder, and 100, 160, 200 and 300 for the hybrid-grid stiffened cylinder. Postbuckling analyses of grid-stiffened cylinders are conducted using a commercial nonlinear finite element analysis code, ABAQUS, to derive the shell knockdown factor. The single perturbation load approach is applied to represent the geometrical initial imperfection of a cylinder. Knockdown factors are derived for both the conventional orthogrid and hybrid-grid stiffened cylinders for different shell thickness ratios. Knockdown factor functions in terms of shell thickness ratio are obtained by curve fitting with the derived shell knockdown factors for the two grid-stiffened cylinders.
Findings
For the two grid-stiffened cylinders, the derived shell knockdown factors are all higher than the previous NASA’s shell knockdown factors for various shell thickness ratios, ranging from 100 to 400. Therefore, the shell knockdown factors derived in this study may facilitate in the development of lightweight structures of space launch vehicles from the aspect of buckling design. For different shell thickness ratios of up to 500, the knockdown factor of the hybrid-grid stiffened cylinder is higher than that of the conventional orthogrid stiffened cylinder. Therefore, it is concluded that the hybrid-grid stiffened cylinder is more efficient than the conventional orthogrid-stiffened cylinder from the perspective of buckling design.
Practical implications
The obtained knockdown factor functions may provide the design criteria for lightweight cylindrical structures of space launch vehicles.
Originality/value
Derivation of shell knockdown factors of hybrid-grid stiffened cylinders considering various shell thickness ratios is attempted for the first time in this study.
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The day before, by one vote, the National Assembly rejected an unprecedented attempt by prosecutors to arrest the leader of the main opposition party, Lee Jae-myung, over…
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DOI: 10.1108/OXAN-DB276406
ISSN: 2633-304X
Keywords
Geographic
Topical
Meanwhile, the leader of the opposition and a ruling party lawmaker have been hospitalised after serious assaults (in the former case, politically motivated). There are also…
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DOI: 10.1108/OXAN-DB284941
ISSN: 2633-304X
Keywords
Geographic
Topical
While several probes into insurrection charges against Yoon are under way, lack of clarity on his status and legitimacy has created a limbo that is damaging, unconstitutional…
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DOI: 10.1108/OXAN-DB291576
ISSN: 2633-304X
Keywords
Geographic
Topical
Yoon’s gaffes and misjudgements have cost him support ahead of the polls, although turnout and the impact of third parties remain possible swing factors.