• Journal of Astronomy and Space Sciences
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• v.41 no.1
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• pp.43-60
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• 2024

Korea Pathfinder Lunar Orbiter (KPLO) is South Korea's first space exploration mission, developed by the Korea Aerospace Research Institute. It aims to develop technologies for lunar exploration, explore lunar science, and test new technologies. KPLO was launched on August 5, 2022, by a Falcon-9 launch vehicle from cape canaveral space force station (CCSFS) in the United States and placed on a ballistic lunar transfer (BLT) trajectory. A total of four trajectory correction maneuvers were performed during the approximately 4.5-month trans-lunar cruise phase to reach the Moon. Starting with the first lunar orbit insertion (LOI) maneuver on December 16, the spacecraft performed a total of three maneuvers before arriving at the lunar mission orbit, at an altitude of 100 kilometers, on December 27, 2022. After entering lunar orbit, the commissioning phase validated the operation of the mission mode, in which the payload is oriented toward the center of the Moon. After completing about one month of commissioning, normal mission operations began, and each payload successfully performed its planned mission. All of the spacecraft operations that KPLO performs from launch to normal operations were designed through the system operations design process. This includes operations that are automatically initiated post-separation from the launch vehicle, as well as those in lunar transfer orbit and lunar mission orbit. Key operational procedures such as the spacecraft's initial checkout, trajectory correction maneuvers, LOI, and commissioning were developed during the early operation preparation phase. These procedures were executed effectively during both the early and normal operation phases. The successful execution of these operations confirms the robust verification of the system operation.

• The KIPS Transactions:PartD
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• v.9D no.5
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• pp.755-768
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• 2002

We investigate the effect of the data skew of join attributes on the performance of a pipelined multi-way hash join method, and propose two new hash join methods with load balancing capabilities. The first proposed method allocates buckets statically by round-robin fashion, and the second one allocates buckets adaptively via a frequency distribution. Using hash-based joins, multiple joins can be pipelined so that the early results from a join, before the whole join is completed, are sent to the next join processing without staying on disks. Unless the pipelining execution of multiple hash joins includes some load balancing mechanisms, the skew effect can severely deteriorate system performance. In this paper, we derive an execution model of the pipeline segment and a cost model, and develop a simulator for the study. As shown by our simulation with a wide range of parameters, join selectivities and sizes of relations deteriorate the system performance as the degree of data skew is larger. But the proposed method using a large number of buckets and a tuning technique can offer substantial robustness against a wide range of skew conditions.

• Journal of KIISE:Databases
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• v.29 no.3
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• pp.180-192
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• 2002

We investigate the effect of the data skew of join attributes on the performance of a pipelined multi-way hash join method, and propose two new harsh join methods in the shared-nothing multiprocessor environment. The first proposed method allocates buckets statically by round-robin fashion, and the second one allocates buckets dynamically via a frequency distribution. Using harsh-based joins, multiple joins can be pipelined to that the early results from a join, before the whole join is completed, are sent to the next join processing without staying in disks. Shared nothing multiprocessor architecture is known to be more scalable to support very large databases. However, this hardware structure is very sensitive to the data skew. Unless the pipelining execution of multiple hash joins includes some dynamic load balancing mechanism, the skew effect can severely deteriorate the system performance. In this parer, we derive an execution model of the pipeline segment and a cost model, and develop a simulator for the study. As shown by our simulation with a wide range of parameters, join selectivities and sizes of relations deteriorate the system performance as the degree of data skew is larger. But the proposed method using a large number of buckets and a tuning technique can offer substantial robustness against a wide range of skew conditions.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3447-3455
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• 1999

Database correctness is guaranteed by standard transaction scheduling schemes like two-phase locking for the context of concurrent execution environment in which short-lived ones are normally mixed with long-lived ones. Traditional syntax-oriented serializability notions are considered to be not enough to handle in particular various types of transaction in terms of duration of execution. To deal with this situation, altruistic locking has attempted to reduce delay effect associated with lock release moment by use of the idea of donation. An improved form of altruism has also been deployed in extended altruistic locking in a way that scope of data to be early released is enlarged to include even data initially not intended to be donated. In this paper, we first of all investigated limitations inherent in both altruistic schemes from the perspective of alleviating starvation occasions for transactions in particular of short-lived nature. The idea of two-way donation locking(2DL) has then been experimented to see the effect of more than single donation in distributed database systems. Simulation experiments shows that 2DL outperforms the conventional two-phase locking in terms of the degree of concurrency and average transaction waiting time under the circumstances that the size of long-transaction is in between 5 and 9.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.116-126
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• 2021

Ground Component Command (GCC) has been developing operational planning and execution systems to implement "Decisive Integrated Operations", which is the concept of ground operations execution, and achieved remarkable results. In particular, "Simultaneous Offense-Defense Integrated Operations" is developed mainly to neutralize enemies in deep areas and develop favorable conditions for the allies early by simultaneously attacking and defending from the beginning of the war. On the other hand, it is limited to providing scientific and reasonable support for the commander's decision-making process because analyzing the effects of the deep operation with existing M&S systems is impossible. This study developed a model for analyzing the effects of deep operations that can be used in the KJCCS. Previous research was conducted on the effects of surveillance, physical strike, and non-physical strike, which are components of deep operations to find the characteristics and limitations and suggest a research direction. A methodology for analyzing the effects of deep operations reflecting the interactions of components using data was then developed by the GCC, and input data for each field was calculated through combat experiments and a literature review. Finally, the Deep operations Effect CAlculating Model(DECAM) was developed and distributed to the GCC and Corps battle staff during the ROK-US Combined Exercise. Through this study, the effectiveness of the methodology and the developed model were confirmed and contribute to the development of the GCC and Corps' abilities to perform deep operations.

• Asia Marketing Journal
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• v.15 no.1
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• pp.169-188
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• 2013

Established in 2006 as the forward integration effort by Taesung Industry, the major cosmetic packaging company, TONYMOLY has phenomenally grown to one of the major cosmetic brand companies in the submarket called, 'one brand-shop' of cosmetic market since 2008, after overcoming the crisis of 'going out of business' in a couple of early years. Within a relatively short period of time, TONYMOLY's performances have dramatically improved in terms of metrics such as growth in sales revenue, the number of stores, the average sales per store, transaction value per customer, the number of monthly transactions, the number of membership-based customers, and overseas sales. In this case study, we have examined TONYMOLY's recent marketing activities which may explain the plausible reasons behind the substantial growth of a small but smart cosmetic company. Above all, the first key success factor of TONYMOLY would be found in its adherence to the clear philosophy of the customer value proposition and/or the differentiated position of TONYMOLY as a brand of providing value. Second, this brand concept of value was first penetrated and welcomed among the foothold customer target group of mid and late teens with appropriate products, while the target groups were later expanded into the age group of twenties along with expansion of relevant products. Third, its differentiation efforts have been concrete and meaningful by utilizing unique ingredients in its product development and marketing efforts, unique fun packaging, and continuously introducing new hit-selling products as well as managing steady-selling products. Fourth, TONYMOLY has been smart enough to use its limited marketing money efficiently and effectively in its marketing communication activities. Viral marketing, PPL, and concentrated media planning and execution turned out to produce effective and efficient market-based performances such as awareness, word-of-mouth, and sales. Lastly, the marketing leadership of CEO and top management, emphasizing communications and interactions, was confirmed in the relationship quality with and trust level of its franchisees and internal employees. These key success factors may explain the recent phenomenal market performances of TONYMOLY. Despite recent successes, the major issues are presented for TONYMOLY to consider for maintaining its sustainable advantages and growth. The first issue concerns TONYMOLY's choice of growth philosophy between product/brand-centric marketing and customer-centric marketing. The second challenging issue relates to how TONYMOLY can cope with 'growing pains' plausibly accompanied with the rapid growth.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.6
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• pp.27-42
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• 2020

Startup accelerators have emerged as new investment entities that help early startups, which are not easy to survive continuously due to lack of funds, commercialization capabilities, and experiences. As their positive performance on early startups and the ecosystem has been proven, the number of early startups which want to receive their investment is also increasing. However, they are vaguely preparing to attract accelerators' investment because they do not have any information on what factors the accelerators consider important. In addition, researches on startup accelerators are also at an early level, so there are no remarkable prior studies on factors that decide on investment. Therefore, this study aims to help startups prepare for investment attraction by looking at what factors are important for accelerators to invest, and to provide meaningful implications to academia. In the preceding study, we derived five upper level categories, 26 lower level accelerators' investment determinants through the qualitative meta-synthesis method, secondary data analysis, observation on US accelerators and in-depth interviews. In this study, we want to derive important implications by deriving priorities of the accelerators' investment determinants. Therefore, we used AHP that are evaluated as the suitable methodology for deriving importance and priority. The analysis results show that accelerators value market-related factors most. This means that startups that are subject to investment by accelerators are early-stage startups, and many companies have not fully developed their products or services. Therefore, market-related factors that can be evaluated objectively seem to be more important than products (or services) that are still ambiguous. Next, it was found that the factors related to the internal workforce of startups are more important. Since accelerators want to develop their businesses together with start-ups and team members through mentoring, ease of collaboration with them is very important, which seems to be important. The overall priority analysis results of the 26 investment determinants show that 'customer needs' and 'founders and team members' understanding of customers and markets' (0.62) are important and high priority factors. The results also show that startup accelerators consider the customer-centered perspective very important. And among the factors related to startups, the most prominent factor was the founder's openness and execution ability. Therefore, it can be confirmed that accelerators consider the ease of collaboration with these startups very important.

• Journal of Gifted/Talented Education
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• v.11 no.3
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• pp.131-153
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• 2001

The importance of identifying gifted children during early childhood is becoming recognized. Nonetheless, most researchers preferred to study the primary and secondary levels where children are already and more clearly demonstrating what talents they have, and where more reliable predictions of gifted may be made. Comparatively lisle work has been done in this area. When we identify giftedness during early childhood, we have to consider the potential of the young children rather than on actual achievement. Giftedness during early childhood is still developing and less stable than that of older children and this prevents us from making firm and accurate predictions based on children's actual achievement. Dynamic assessment, based on Vygotsky's concept of the zone of proximal development(ZPD), suggests a new idea in the way the gifted young children are identified. In light of dynamic assessment, for identifying the potential giftedness of young children. we need to involve measuring both unassisted and assisted performance. Dynamic assessment usually consists of a test-intervene-retest format that focuses attention on the improvement in child performance when an adult provides mediated assistance on how to master the testing task. The advantages of the dynamic assessment are as follows: First, the dynamic assessment approach can provide a useful means for assessing young gifted child who have not demonstrated high ability on traditional identification method. Second, the dynamic assessment approach can assess the learning process of young children. Third, the dynamic assessment can lead an individualized education by the early identification of young gifted children. Fourth, the dynamic assessment can be a more accurate predictor of potential by linking diagnosis and instruction. Thus, it can make us provide an educational treatment effectively for young gifted children.

• Journal of Preventive Medicine and Public Health
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• v.53 no.4
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• pp.228-232
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• 2020

Coronavirus disease 2019 (COVID-19) is inflicting a brutal blow on humankind, and no corner of the world has been exempted from its wrath. This study analyzes the chief control measures and the distinctive features of the responses implemented by Korea and the United States to contain COVID-19 with the goal of extracting lessons that can be applied globally. Even though both nations reported their index cases on the same day, Korea succeeded in flattening the curve, with 10 752 cases as of April 28, 2020, whereas the outbreak skyrocketed in the United States, which had more than 1 million cases at the same time. The prudent and timely execution of control strategies enabled Korea to tame the spread of the virus, whereas the United States paid a major price for its delay, although it is too early to render a conclusive verdict. Information pertaining to the number of people infected with the virus and measures instituted by the government to control the spread of COVID-19 was retrieved from the United States Centers for Disease Control and Prevention and the Korea Centers for Disease Control and Prevention websites and press releases. Drawing lessons from both nations, it is evident that the resolution to the COVID-19 pandemic lies in the prudent usage of available resources, proactive strategic planning, public participation, transparency in information sharing, abiding by the regulations that are put into place, and how well the plan of action is implemented.

• Korean Institute of Interior Design Journal
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• v.27 no.2
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• pp.55-67
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• 2018

There is a growing interest on and expansion of rights of people with disabilities. Among them, people with visual impairment show high adaptation to environments in comparison to people with other types of disabilities, thus a large percentage of them live in their own houses rather than residing in a care facility. According to the housing status of people with visual impairment, the ratio of their residence in rural areas is high. In rural areas people who have disabilities often live in poor residential environments, requiring much improvement. However, such improvement is too costly for them to pay, and home modification that does not fully consider the user, may cause less efficiency and another dangerous situation to people with disabilities. The purpose of this study is to delineate empirical lessons for direction of customized home modification for people with disabilities through analysis of process of home modification including the execution as a intervention. This study used qualitative method to examine and analyzed the entire customized home modification process. The conclusion of this study is as follows. First, home modification measures should be derived considering the suitability of the target building for the specific condition of residents. Second, discussions with various stakeholders from the early stage during which proper home modification measure is searched are essential for realizing appropriate customized home modification. This study has significance in that it provides the direction for customized home modification for people with disabilities as well as empirical data that could reduce trials and errors in the future.