• Journal of the military operations research society of Korea
• /
• v.33 no.1
• /
• pp.43-58
• /
• 2007

With every Yasukuni Shrine visit by a Japanese Prime Minister, one can expect that the Korean government will jump up and down to condemn Japan. The blatant antagonism between the two powerhouses in Asia, lingering around more than sixty years after the end of the colonial period, is unmistakably more than interplay of their colonial history. It is an illumination of a largely unsettled post-colonial diplomacy that was executed in the name of economic advancement. The purpose of this paper is to shed lights on a largely ignored subject matter that unambiguously shaped the peculiar relationship between Korea and Japan.

• Journal of the Korean Society for Heat Treatment
• /
• v.3 no.2
• /
• pp.1-9
• /
• 1990

Since the reverse shape memory effect(RSME) was reported in a CuZnAl alloy, further study has been done on the mechanism of this phenomenon and reported that it occurs by the bainitic transformation. But the present authors revealed in the previous work that the RSME in a B2 CuZnAl alloy is not caused by the shear process involved in the bainitic transformation and also that the RSME takes place as the remaining ${\alpha}^{\prime}{_2}$ phase, which is two-step transformed strain induced martensite, is newly transformed into ${\alpha}$ phase. In order to provide further evidence in supporting the facts, thus, more detailed investigations have been carried out in a $DO_3$ CuZnAl alloy.

• International Journal of Precision Engineering and Manufacturing-Green Technology
• /
• v.5 no.5
• /
• pp.605-612
• /
• 2018

This work investigates the relationships between the static mechanical properties of Ti-6Al-4V manufactured through selective laser melting (SLM) and post-process heat treatments, namely stress relieve, annealing and hot isostatic pressing (HIP). In particular, Ti-6Al-4V parts were fabricated in three different build orientations of X, Z, and $45^{\circ}$ to investigate the multi-directional mechanical properties. The results showed that fully densified Ti-6Al-4V parts with densities of up to 99.5% were obtained with optimized SLM parameters. The microstructure of stress relieved and mill annealed samples was dominated by fine ${\alpha}^{\prime}$ martensitic needles. After HIP treatment, the martensite structure was fully transformed into ${\alpha}$ and ${\beta}$ phases (${\alpha}+{\beta}$ lamellar). Within the realm of tensile properties, the yield and ultimate strength values were found statistically similar with respect to the built orientation for a given heat treatment. However, the ductility was found orientation dependent for the HIP samples, where a lower value was observed for samples built in the X direction.

• Journal of Forest and Environmental Science
• /
• v.35 no.2
• /
• pp.121-139
• /
• 2019

Decomposition of litter is a function of various interrelated variables, both biotic and abiotic factors. Litter decomposition acts like a natural fertilizer play a prime role in maintaining the productivity and nutrient cycling in agroforestry systems. There are few studies of decomposition carried out in agroforestry systems with coffee; so it is necessary to perform more research work to fill the research gap, which will allow a better understanding of the management of the coffee agroforestry systems. This paper is based on the theoretical and conceptual aspects of leaf litter decomposition in agroforestry systems, emphasizing the combination with coffee cultivation and critically examined the role of the different factors involved in the decomposition. This study made a comparison of different investigations with regards to weight loss, decomposition rates (k), initial chemical composition, and release of the main nutrients. This study suggested that it is necessary to implement studies of decomposition and mineralization, and the microflora and fauna associated with these processes, so that serves as an important tool to develop a model for enabling a description of the short, medium, and long-term dynamics of soil nutrients in coffee agroforestry systems.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.9
• /
• pp.4788-4813
• /
• 2019

In this paper, we introduce concepts of optimal and near optimal secret data hiding schemes. We present a new digital image steganography approach based on the Galois field $GF(p^m)$ using graph and automata to design the data hiding scheme of the general form ($k,N,{\lfloor}{\log}_2p^{mn}{\rfloor}$) for binary, gray and palette images with the given assumptions, where k, m, n, N are positive integers and p is prime, show the sufficient conditions for the existence and prove the existence of some optimal and near optimal secret data hiding schemes. These results are derived from the concept of the maximal secret data ratio of embedded bits, the module approach and the fastest optimal parity assignment method proposed by Huy et al. in 2011 and 2013. An application of the schemes to the process of hiding a finite sequence of secret data in an image is also considered. Security analyses and experimental results confirm that our approach can create steganographic schemes which achieve high efficiency in embedding capacity, visual quality, speed as well as security, which are key properties of steganography.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.3
• /
• pp.1395-1403
• /
• 2021

The COVID-19 pandemic is having an adverse impact on Bangladesh's economy by affecting millions of people's life and hampering their income sources. The outbreak of COVID-19 has created more pressure on the labor market. The pandemic reduces employment opportunities as most of the companies have stopped their recruitment process to cut their operational costs, which increases the rate of graduate unemployment in Bangladesh. Hence, this study aims to investigate the impact of COVID-19 on graduate employability in Bangladesh that adversely affects the income of families and eventually the nation's economy. A literature review has been conducted from secondary sources to evaluate the impact, which shows that the rate of graduate unemployment increased from 47% to 58% in 2020 with an expected annual loss estimated at $53 million. Findings also reveal that the prime reasons for graduate employability are low demand and huge supply of graduates in the labor market, lack of professional skills of graduates, ineffective education system, etc. The study suggests that the government of Bangladesh should develop some policies to overcome this problem such as ensuring employment subsidies, implementing skills development programs, improving labor market flexibility, initiating credit programs for generating employment, and developing entrepreneurial ecosystems in Bangladesh.

• Journal of Korean Society for Quality Management
• /
• v.47 no.4
• /
• pp.911-926
• /
• 2019

Purpose: In an infinite market competition, companies are adopting management systems to gain a competitive advantage. The expectancy effect of the management system is management performance improvement and accurate measurements. These can be made through quality records with integrity and maintainability. This paper examines the operation of records management standards, which are records, storage and management standards for quality records to understand the needs of records management standards and empathize with their needs. Methods: This paper examines PEC's (Pields Engineering Co., Ltd.) specific processes and standards for integrating individual management systems and establishing records management standards. We also look at the specific features of the Search Tool and Document Storage Management Standards that support records management standards. Results: The integration process of PEC's individual management system consists of five steps. A PDCA-based process was established to erode the confusion and inefficiencies caused by overlap between individual management systems. Also, by accurately grasping corporate competence, PEC established a record management standard suitable for the characteristics of the company. PEC's records management standards are used as a useful standard for organizing quality records, and have an impact on management performance improvement. Conclusion: PEC's records management standards enable the verification of quality performance rates and performance measures. Companies can implement appropriate quality improvement strategies based on the numbers identified by introducing records management standards. Companies can succeed in improving management performance when operating quality management that combines performance measurement techniques and records management standards.

• Korean Institute of Interior Design Journal
• /
• v.23 no.3
• /
• pp.48-55
• /
• 2014

Luis Barragan is a representative Mexican architect. He designed architectural space as a local architect in consideration of the Mexico's harsh Mediterranean climate. His manifestation of the regionality can be found mainly in his precise expression of light. Such method and concept of using light in Barragan's architecture made a huge impact on later architects but detailed studies on this issue have not been made actively. Hence, this paper intended to suggest a starting point or an orientation by illustrating the characteristics of using and expressing light in architecture through his cases of housing works. The study method was as follows. First, the general characteristics of light were identified by analyzing the elements of architectural space that dealt with light and the characteristics of expressing light shown in the architectural space. Second, the architectural background of Luis Barragan and the architectural space elements of the light expressed in his architectural space were extracted to form a hypothetical ground. Third, five of his works on the houses in his prime (after the year of 1945) were analyzed to explore the characteristics of relational representation between light and the architectural space elements in his architecture. Through this process, it was learned that, in his architectural works, light was the embodiment of the location-related, time-based, daily and illusionary experience into architecture. In addition, meditative light could be experienced by contrasting the soft and dispersed light and shadow of the inside space of Barragan's houses with the strong external light. Therefore, through the process above, this study is hoped to provide an opportunity for the contemporary architects of our era to rethink the fundamental correlation between architecture and light.

• The Journal of the Korea Contents Association
• /
• v.14 no.10
• /
• pp.472-485
• /
• 2014

This study focuses on the news making system of the prime time news of PSB in Korean society, where the presence of ethnic minorities is increasing rapidly. Although the World Wide Web has become one of the most attractive media over the last decade, Korean PSB, Korean Broadcasting System (KBS), still remains the most popular and influential medium. Therefore, the process of analyzing news making system of ethnic minorities in Korean society represented in Korean PSB as a social construction is meaningful in that it provides an important key to understand the cultural and political background and characteristics of society. For this purpose, the article tries to understand news making process when producing news related to ethnic minorities in the Korean society such as migrant workers, married migrant women and mixed-heritage children of multicultural families by interview with ten reporters in KBS. As a result, most KBS reporters had stereotypes towards multiculturalism and migrants and news reports relating to ethnic minorities are usually produced routinely, using a set of rules that have become part of KBS culture.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2002.11a
• /
• pp.43-49
• /
• 2002

A7003 alloy has characteristics of their excellent weldability, high corrosion resistance and superior plastic working however the broadening of application for the alloy has been hampered by the lower extrudability associated by Mg content. For improvement of extrudability and enhanced recovery efficiency during Al scrap recyeling, it has been generally practiced to reduce Mg content in A7003 alloy. Therefore, it is necessary to investigate the influence of Mg content on mechanical strength and extrudability of A7003 alloy. For efficient material processing which has small amounts, life cycle assessment in material processing(MLCA) is evaluated. The quantitative analysis of energy requirements and $CO_2$ emission for production of A7003 extruded bar are estimated with different Mg content and billet pre-heating process (heating source by light oil or LPG). In particular, the estimation of energy requirements was performed within shipping and gating range (except the mining and extraction stages)to investigate the influence of the variables on energy requirements and $CO_2$ emission in detail. As Mg content increased, the flow stress and the extrusion pressure for A7003 alloy increased. It has been thought that an increment in extrusion pressure with increasing Mg content is caused by the solid solution hardening of Mg atoms in the matrix and increment in volume fraction of intermetallic compound, $Mg_2Si$. The extrudability and the tensile strength are equal to, or above that of conventional A 7003 alloy even the content of Mg varied from $1.1wt.\%\;to\;0.5wt.\%$ alloy. This means that minimizing the content of Mg in A7003 alloy can enhance recovery efficiency during Al scrap recycling. It can be quoted that rather than Mg content energy source for billet heating is a prime factor to determine the atmospheric $CO_2$ emission.