• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.3D
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• pp.259-267
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• 2012

The development of construction automation systems is proposed as a potent solution to the difficulties encountered by the construction industry and the preparation for the rapidly changing construction environment. A research concerning an intelligent excavation system has taken place since 2006. The intelligent excavation system has several functions for environment sensing, 3D site modeling, work planning, work path generation, unmaned control, and information management. This paper presents a space information model and a work path simulator for work planning and work path generation which is one of key technologies required to apply the earthwork system to the real world. A data structure for an earthwork site is suggested. It overcomes the limitations of previous data structures such as Quadtree and Octree. The work path simulator can generate an effective work path with considering information on work environment, equipment and operator's heuristic. The work path generated by the simulator is compared with that suggested by human operators.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.1
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• pp.455-472
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• 2020

As a user in modern societies with the rapid growth of Internet environment and more complicated business flow processes in order to be effective at work and accomplish things on time when the manager of the company went for a business trip, he/she need to delegate his/her signing authorities to someone such that, the delegatee can act as a manager and sign a message on his/her behalf. In order to make the delegation process more secure and authentic, we proposed a secure and efficient identity-based proxy signcryption in cloud data sharing (SE-IDPSC-CS), which provides a secure privilege delegation mechanism for a person to delegate his/her signcryption privilege to his/her proxy agent. Our scheme allows the manager of the company to delegate his/her signcryption privilege to his/her proxy agent and the proxy agent can act as a manager and generate signcrypted messages on his/her behalf using special information called "proxy key". Then, the proxy agent uploads the signcrypted ciphertext to a cloud service provider (CSP) which can only be downloaded, decrypted and verified by an authorized user at any time from any place through the Internet. Finally, the security analysis and experiment result determine that the proposed scheme outperforms previous works in terms of functionalities and computational time.

• Journal of Biosystems Engineering
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• v.36 no.2
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• pp.116-121
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• 2011

This study was conducted to develop a robust navigator which could be in positioning for precision farming through developing a plural GPS receiver with 4 sets of GPS antenna. In order to improve positioning accuracy by integrating GPS signals received simultaneously, the algorithm for processing plural GPS signal effectively was designed. Performance of the algorithm was tested using a simulation program and a fixed point on WGS 84 coordinates. Results of this study are aummarized as followings. 1. 4 sets of lower grade GPS receiver and signals were integrated by kalman filter algorithm and geometric algorithm to increase positioning accuracy of the data. 2. Prototype was composed of 4 sets of GPS receiver and INS components. All Star which manufactured by CMC, gyro compass made by KVH, ground speed sensor and integration S/W based on RTOS(Real Time Operating System)were used. 3. Integration algorithm was simulated by developed program which could generate random position error less then 10 m and tested with the prototype at a fixed position. 4. When navigation data was integrated by geometrical correction and kalman filter algorithm, estimated positioning erros were less then 0.6 m and 1.0 m respectively in simulation and fixed position tests.

• Journal of Korea Multimedia Society
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• v.9 no.7
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• pp.773-781
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• 2006

XML is a standard language to express and exchange the data over the web. Recently, researches about techniques that storing XML documents into RDBMS and managing it have been progressed. These researches use a technique that are receiving the DTD document as an input and generate the relational schema from it. Existing researches, however, do not consider the semantic preservation because of the simplification of the DTD. Further, because existing studies only focus on the preservation technique to store information such as content and structure, there is a troublesomeness that have to use the stored-procedure or trigger for the data integrity during the stores of XML documents. This paper proposes a improved Inlining technique to create effective relations and to preserve semantics which can be inferred from DTD.

• The KIPS Transactions:PartC
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• v.15C no.5
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• pp.375-382
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• 2008

As the use of Internet and information communication technology is being generalized, the SSL protocol is essential in Internet because the important data should be transferred securely. While the SSL protocol is designed to defend from active attack such as message forgery and message alteration, the cipher suite setting can be easily modified. If the attacker draw on a malfunction of the client system and modify the cipher suite setting to the symmetric key algorithm which has short key length, he should eavesdrop and cryptanalysis the encrypt data. In this paper, we examine the domestic web site whether they generate the security session in the symmetric key algorithm which has short key length and propose the solution of the cipher suite setting problem.

• Journal of Korean Public Health Nursing
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• v.30 no.2
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• pp.326-336
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• 2016

Purpose: This study was conducted to help with the development of an intervention program in efforts to prevent suicidal ideation and suicide. The study also sought to generate strategies for improving health conditions by ascertaining and analyzing potential factors that may influence suicidal ideation according to age group in adults. Methods: Data on general characteristics and suicidal ideation from 447 adults aged between 20 and 59 years, living in Y city, Gyeonggi Province, South Korea, were collected based on a structured questionnaire, The data were analyzed using SPSS20.0 statistics program. Results: The results showed that 48.6% of young and older adults have experienced suicidal ideation while 44.5% of middle-aged adults have had suicidal thoughts. With regard to suicidal ideation, young and older adults revealed relevant differences in terms of gender, residential type, degree of stress and subjective physical and mental health, while middle-aged adults revealed relevant differences in terms of marital status and degree of stress. With regard to factors that influence suicidal ideation, it was found that the relevant variables of young and older adults included gender, residential type, depression, degree of stress, and subjective physical and mental health, while for middle-aged adults, relevant variables included marital status and degree of stress. Conclusion: These findings indicate that as stress and depression decreases, subjective physical and mental health improves. Therefore, this study proposes that developing and operating an intervention program can help prevent suicidal ideation in local residents.

• International Journal of Concrete Structures and Materials
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• v.7 no.3
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• pp.225-238
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• 2013

In this study, a two-layer feed-forward neural network was constructed and applied to determine a mapping associating mix design and testing factors of cement-nano silica (NS)-rice husk ash ternary blended concrete samples with their performance in conductance to the water absorption properties. To generate data for the neural network model (NNM), a total of 174 field cores from 58 different mixes at three ages were tested in the laboratory for each of percentage, velocity and coefficient of water absorption and mix volumetric properties. The significant factors (six items) that affect the permeability properties of ternary blended concrete were identified by experimental studies which were: (1) percentage of cement; (2) content of rice husk ash; (3) percentage of 15 nm of $SiO_2$ particles; (4) content of NS particles with average size of 80 nm; (5) effect of curing medium and (6) curing time. The mentioned significant factors were then used to define the domain of a neural network which was trained based on the Levenberg-Marquardt back propagation algorithm using Matlab software. Excellent agreement was observed between simulation and laboratory data. It is believed that the novel developed NNM with three outputs will be a useful tool in the study of the permeability properties of ternary blended concrete and its maintenance.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.371-372
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• 2008

Many kinds of electrodes have been developed in various forms and shapes for measurement of bio potential signal. Textile electrode has benefit of collect long tenn data monitoring because of it is non-consciousness, convenient and do not occur skin irritation. However, It is very difficult to acquire available data due to high impedance of electrode and unstable skin-electrode contact which generate motion artifact. Also snap button which usually used as mediator between textile and measurement device cause change of electrical characteristics. In this paper, we inflated textile electrode to stabilize contact and add conductive silver paste between textile and snap button to improve conductance. To compare the performance of two methods, flat or inflated and add conductive paste or not, four types of electrodes are tested on each impedance and SNR by ECG measurement. In result, the first type electrode which flat and non-conductive paste showed the worst performance and the last type electrode which is inflated shape and contain conductive paste show the best performance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.4
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• pp.573-582
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• 2020

Fuzzing is a method of testing software by randomly generating test cases. Since its introduction, a variety of fuzzing techniques have been studied. Among them, mutation-based fuzzing is an efficient method that finds real-world bugs even though it uses a simple approach such as probabilistic bit-flipping and character substitution. However, the interpreter fuzzing has difficulty in applying general mutation techniques because the interpreter requires grammar and semantic correctness input values. In this paper, we present a novel mutation-based fuzzing on JavaScript interpreters with a dynamic data flow analysis. To this end, we implement JMFuzzer that can generate various types of mutated test cases that operate normally without runtime errors in JavaScript interpreter considering syntax and semantics. As a result, we found numerous unknown vulnerabilities in the latest JavaScript interpreters. We reported all of them to the vendors.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.564-567
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• 2003

XML has weakness problems on document modulation and elimination of data Because of the XML gives priority to present data format, XML electrical signature, XML cryptography, or XML access control is provided to overcome those weakness problems. However, structured XML efficiency contravention problem occurred from XML encryption and absence of protection from DTD attack are still remains unsolved. In this paper, we provide XML scheme that satisfies both efficiency and encryption. DTD is unnecessary because XML scheme supports formatting(Well-Formed XML) XML documents and it also include meta information. Because of the XML scheme has possibility to generate each XML document dynamically and self efficiency investigator rule, it has an advantage on extendability of DID based encryption of XML documents.