• Journal of Internet Computing and Services
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• v.12 no.4
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• pp.181-194
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• 2011

Server push which is technology of sending contents from servers to browsers in real time using long polling requests enables real time bidirectional communications between servers and browsers in HTTP environment. Recently, thanks to the rapid supply of mobile devices having ability of full browsing, server push is being applied to various applications. However, because servers providing services should offer distributed contents to a large number of users simultaneously in various user environments, they have a burden that offers contents quickly distinguishing much more concurrent users than before. The method of message exchange so far achieved in distributed server environment has difficulties in the performance of simultaneous user request process, the identification of users and the contents delivery. In this paper, We proposed message exchange architecture between servers for offering server push in the distributed server environment. The proposed architecture enables message exchange in the method of push between servers based on event driven architecture. In addition, the proposed architecture enables flexible identification of a event agent and event processing under the connected environment of a lot of users. In this paper, we designed and implemented the proposed architecture and compared performance with the previous way through a performance test. In addition, function is confirmed through the case realization. As a result of the performance test, the proposed architecture can lessen the use of server Thread and response time of users and increase simultaneous throughput.

• The Journal of Engineering Geology
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• v.13 no.3
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• pp.321-334
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• 2003

This study is aimed at the effective measurement plan of discontinuity orientation on rock mass. The discontinuity orientation is expressed as three methods. strike/dip. dipdirection/dip (a three digit number / a two digit number) and right hand rule. Generally, strike/dip is measured with clinometer. and dipdirection/dip with silva compass(type15). A sign of strike/dip. discontinuity orientation is used to geological survey. and dipdirection/dip to engineering. Dipdirection/dip converted by strike/dip measured with clinometer is useful on the statistical analysis of a lot of data. To measure the azimuth of the dip with clinometer and to change strike/dip to dipdirection/dip may have potential errors in each person. The newly designed apparatus, clinometer equipped by a rotational azimuth plate and an arrow to measuring strike and dipdirection, has been developed to measure effectively the discontinuity orientation with two method (strike/dip and dipdirection/dip). The measuring method of discontinuity orientation with clinometer having newly designed apparatus is effective one for accurate measurement of strike as well as dipdirection which is degrees counted clockwise from true north. Used by clinometer with newly designed apparatus, concurrent measuring strike/dip and dipdirecton/dip of discontinuity is possible. In application to measuring discontinuity orientation on rock slope, it has been recognized that the newly designed method, unambiguously, led to drop measuring errors comparing with existing measuring apparatuses. Therefore, it is considered that measuring method of discontinuity orientation (strike/dip and dipdirecton/dip) by the newly designed apparatus is useful to one in geological engineering investigation of road design, and to unskilled investigator.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.368-374
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• 2020

Journaling file systems (JFS) manage changes of file systems not yet committed in a data structure known as a journal to restore the file system in the event of an unexpected failure. Extra write operations required for journaling negatively affect the performance of JFS. The high-performance and byte-addressable non-volatile memory (NVM) was expected to easily mitigate these performance problems by providing NVM space as journal storage. However, even with such non-volatile memory technologies, performance problems still arise due to scalability problems inherent in processing transactions of JFS. To solve this problem, we proposes a technique for processing file system transactions for scalable performance. To this end, lock-free data structures are used and multiple I/O requests are allowed to simultaneously be processed on high-performance storage devices with multiple I/O channels. We evaluate the file system with the proposed technique by comparing the original ext4 file system and the recent proposed NVM-based journaling file system on a multi-core server, and experimental results show that our file system has better performance (up-to 2.9/2.3 times) than the original ext4 file system and the recent NVM-based journaling file system, respectively.

• KIPS Transactions on Software and Data Engineering
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• v.1 no.3
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• pp.159-168
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• 2012

Relation in the new IT environment, such as the SNS, Cloud, Web3.0, has become an important factor. And these relations generate a transaction. However, existing relational database and graph database does not processe graph structure representing the relationships and transactions. This paper, we propose the technique that can be processed concurrently graph structures and transactions in a scalable complex network system. The proposed technique simultaneously save and navigate graph structures and transactions using the Topic Maps data model. Topic Maps is one of ontology language to implement the semantic web(Web 3.0). It has been used as the navigator of the information through the association of the information resources. In this paper, the architecture of the proposed technique was implemented and design using Cassandra - one of column type NoSQL. It is to ensure that can handle up to Big Data-level data using distributed processing. Finally, the experiments showed about the process of storage and query about typical RDBMS Oracle and the proposed technique to the same data source and the same questions. It can show that is expressed by the relationship without the 'join' enough alternative to the role of the RDBMS.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.9
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• pp.624-629
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• 2013

The relation between performance maintenance conditions and those cost efficiency was studied to choose an optimum operating condition in the seawater desalination pretreatment system. A hollow fiber microfiltration module, which was developed with domestic technology, was tested with the various operating conditions such as chemically enhanced backwash cycles and design dosages of a cleaning chemical. Transmembrane pressure was measured to investigate membrane fouling status and cleaning degree. In addition, economic analysis was performed to compare water production costs by the operation condition. As a result, The operation mode III, chemically enhanced backwash at once a day with 100 mg/L of sodium hypochlorite (NaOCl) was selected. The concurrent evaluation between membrane filtration performance and its economic analysis will be suitable to choose an efficient optimum condition.

• Journal of Internet Computing and Services
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• v.3 no.1
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• pp.81-90
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• 2002

Large-scale distributed applications based on Internet and client/server applications have to deal with series of problems. Load balancing, unpredictable communication delays, and networking failures can be the example of the series of problems. Therefore. sophisticated applications such as teleconferencing, video-on-demand, and concurrent software engineering require an abstracted group communication, CORBA does not address these paradigms adequately. It mainly deals with point-to-point communication and does not support the development of reliable applications that include predictable behavior in distributed systems. In this paper, we present our design, implementation and performance analysis of the group communication using the CORBA-ORB. JAVA-RML and Socket based on distributed computing Performance analysis will be estimated latency-lime according to object increment, in case of group communication using ORB of CORBA the average is 14.5172msec, in case of group communication using RMI of Java the average is 21.4085msec, in case of group communication using socket the average is becoming 18.0714msec. Each group communication using multicast and UDP can be estimated 0.2735msec and 0.2157msec. The performance of the CORBA-ORB group communication is increased because of the increased object by the result of this research. This study can be applied to the fault-tolerant client/server system, group-ware. text retrieval system, and financial information systems.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.2
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• pp.141-150
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• 2001

Manufacturing conb'ol applications consist of concurrent active components such as robots, AGV's (Automatic Guided Vehicles), and conveyors. Running of manufacturing control programs is interactions among those components. We can enhance the productivity and extendability of manufacturing control applications by using the object-oriented teclmology that models those components as reusable objects. But the objects in current object-oriented technology that encapsulate state and behavior infonnation are passive in a sense that those respond only when messages are sent to them. In this paper, we introduce the Distributed Active Object Systems (DAGS) approach that SUPPOltS active objects. Since active objects encapsulate control infonnation in addition to state and behavior information under COREA/Java-based distributed environment, they can represent manufacturing control components better than the objects in ordimuy object-oriented technology. TIus control infonnation provides an object with a featme that can monitor its own status as well as other object's status connected by intelface valiables. Active objects can initiate a behavior according to the change of those status. Therefore, we can sb-uctmally assemble self-initiating active objects by using intelface variables to construct a system without describing bow to control distributed objects by using message passing. As the DAOS approach supports object composability, we can enhal1ce the productivity and extendability of disbibuted manufactming control applications even better than the ordil1alY object-oriented approach. Also, the DAOS approach supports better component reusability with active objects that encapsulate control information .

• Research in Community and Public Health Nursing
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• v.32 no.3
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• pp.368-381
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• 2021

Purpose: The obesity prevention and management program led by public health centers are important in the community. This study aims to identify the current status of obesity prevention and management programs at public health centers and perceptions regarding facilitators and barriers when implementing programs. Methods: This study used a concurrent mixed methods design. A survey was conducted to investigate the current status and infrastructure of the obesity prevention and management program at eighty-three public health centers nationwide. Nine program managers and six local residents with experience in the program were interviewed by using a semi-structured questionnaires. Results: Most of the infrastructure facilities for the program were inadequate, and insufficient budgets and lack of professional staff were identified as barriers. Facilitators included diversification of program delivery methods, operator competence, and visible outcomes and rewards. For the effectiveness of the program, it is vital to have adequate assistants, a sufficient budget, various promotional methods, and connections with various institutions in the community. On this basis, it is acknowledged that the public health center serves as a platform for preventing and managing obesity in the community. Conclusion: It is expected that infrastructure improvements in public health centers and the link with community resources are needed. In addition, there is an urgent need to set standards for obesity prevention and management programs implemented in public health centers to 'resolve regional disparities'.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.218-226
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• 2018

The purpose of this study was to examine the validity and reliability of the Korean version of the nursing students' perception of instructor caring (NSPIC) scale developed by Wade and Kasper for nursing students. We collected data from 219 nursing students in the 3rd to 4th year at three nursing colleges from June 4 to June 20, 2018. Data were analyzed using SPSS 21.0 and AMOS 21.0. An exploratory factor analysis with varimax rotation was performed, resulting in five factors (respectful sharing, confidence through caring, control versus flexibility, supportive learning climate, appreciation of life's meanings) with a total of 27 items. Confirmatory factor analysis supported good convergent and discriminant validities. In addition, the concurrent validity test confirmed that the K-NSPIC scale was a validity tool as the correlation of the clinical learning environment (CLE) scale appeared as r=.64 (p<.001). The Cronbach's alpha coefficient of the K-NSPIC was .88, and Cronbach's alpha coefficient for each of the five factors was .91, .86, .80, .76, and .85; internal consistency was confirmed. It is significant that the K-NSPIC proved applicable as a useful tool for assessing instructor caring. It is also expected that it will assist in the design of programs to improve the caring ability of instructors.

• Asia-Pacific Journal of Business
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• v.11 no.3
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• pp.153-167
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• 2020

Purpose - The purpose of this study is to examine whether social value-related expenditures can be recognized as intangible assets in financial statements. Design/methodology/approach - This study examined social values defined in the economic and management fields and analyzed whether the social values have the characteristics of intangible assets. For this, the general definition of social value was derived from the concept of social value covered in previous studies. Next, we reviewed the definitions and recognition requirements for intangible assets under the current accounting standards. Based on this, we tried to suggest new criteria and disclosure methods for reporting social value-related expenditures that are not currently reported in financial statements as intangible assets in the financial statements and notes. Findings - First, as a criterion for recognizing social value-related expenditure as an intangible asset, we propose a relationship between social value-related expenditure and enterprise value. Where social value-related expenditures have a statistically significant positive impact on corporate value, they are recognized as intangible assets. If social value-related expenditures have a statistically significant negative influence on business value, or the impact of social value-related expenditures on the enterprise value is not statistically significant, it is not recognized as asset. Second, new disclosure plans are proposed according to the combination of intangible assets by category and the relevance of enterprise value. After dividing social value-related expenditures into separate intangible asset categories, if social value-related expenditures have a statistically significant positive impact on corporate value, they are recognized as intangible assets in the financial statements. If expenditures have a statistically significant negative impact on business value, they should be recorded as essential notes. Finally, if the impact of social value-related expenditure on corporate value is not statistically significant, it should be listed as a supplement. Research implications or Originality - This study contributes to the concurrent research in that it is a priori study on whether social value-related expenditure can be recognized as an asset. This study suggests that the economic effect of social expenditure can be recognized in corporate financial statements, thereby providing companies with justification and effectiveness of social value-related expenditure.