• The KIPS Transactions:PartC
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• v.12C no.1 s.97
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• pp.29-36
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• 2005

A key agreement protocol is the most important part to establish a secure cryptographic system and the effort to standardize the key agreement protocols is in rapid progress. Several efficient and secure key agreement protocols have been proposed so far since Diffie-Hellman proposed a public key agreement system in 1976. But, since Diffie-Hellman based key agreement protocols need a lot of computation to establish the session key, they are not suitable for wireless Internet environment. In this paper, we propose the efficient key agreement protocol using Proxy server. The Proposed Protocol gives the security equivalent to that the Diffie-Hellman based Protocol and the computation work of mobile user can be decreased using proxy server.

• The KIPS Transactions:PartC
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• v.10C no.6
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• pp.711-716
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• 2003

We propose a new Interet time synchronization model using danamic linear model and introduce the characteristics of internet transmission delays. SNTP(Simple Network Time Protocol) has been widely used as a time synchronization method on the Internet. While SNTP provides a very simple usage, SNTP may not provide the stable services, since SNTP does not consider the several essential error factors. In order to overcome the instabitily of SNTP, we analyze the process of time estimation of SNTP and find the difference between forward transmission delay and backward transmission delay operates the main error on the estimation of an time offset.

• Convergence Security Journal
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• v.18 no.2
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• pp.133-139
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• 2018

The 5 Game changer means the concepts of the army's operation against the enemy's asymmetric threats so that minimize damage to the public and leads to victory in war in the shortest time. A study of network architecture of Dronebot operation is a key study to carry out integrated operation with integrated C4I system by organically linking several drones battle groups through ICT. The NBC reconnaissance drones can be used instead of vehicles and humans to detect NBC materials and share situations quickly. However, there is still a lack of research on the swarm flight of the NBC reconnaissance drones and the weaknesses of cyber electronic warfare. In this study, we present weaknesses and countermeasures of CBRNs in swarm flight operations and provide a basis for future research.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.7 no.3
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• pp.41-52
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• 1997

In this paper, we analyze two claws of Zhou-Gollmann's protocol. The protocol divide the message into a key K and a ciphertext C. The ciphertext C is delivered to the recipient, but the key K is submitted to the TTP, after the message originator receive the recipient's receipt for the ciphertext. TTP puts the key in the directory which is accesaible to the public. So, the recipient's obtaining the message dependson whether the originator submits the key or not. We will show that the originator. which is in such an advantageous position, could make the protocol be unfair and present how to improve the protocol. On the other hand, Zhou-Gollmann's protocol doesn't provide the secrecy of the message, since the key K is published. This means that, to send a secret message, additional mechanism is required. In this paper, we will present an improvement of Zhou-Gollmann's protocol to keep the message secret. The key distribution of the proposed protocol is based on the Diffie-Hellman's one.

• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.214-222
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• 2022

In these proceedings, we will address the problem of air pollution on the premises of the Cement factory SHARRCEM L.L.C. in Hani Elezit in the Republic of Kosovo respectively around the clinker cooler, rotary kiln, and raw material mill. By air pollution, we mean the introduction of chemicals, particles, or other harmful materials into the atmosphere which in one way or another causing damage to the development of plants and organisms. Air pollution occurs when certain substances are released into the air, which depending on the quantitative level, can be harmful to human health, animals, and the environment in general. The analysis of air shows the influence of the extractive and processing industry on the chemical composition of air. Parameters analyzed though under control such as the case of carbon dioxide, due to the increasing production capacity of cement, the production of hundreds of thousands of cubic meters of CO₂ gas made CO₂ production a concern. With the purchase of the latest technology by the SHARCEM Factory in Hani Elezit, the amount of air pollution has been reduced and the allowed parameters of environmental pollution have been kept under control. Air pollutants are introduced into the atmosphere from various sources which change the composition of the atmosphere and affect the biotic environment.The concentration of air pollutants depends not only on the quantities that are emitted from the sources of air pollution but also on the ability of the atmosphere to absorb or disperse these emissions. Sources of air pollutants include vehicles, industry, indoor sources, and natural resources. There are some natural pollutants, such as natural fog, particles from volcanic eruptions, pollen grains, bacteria, and so on.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.34 no.2
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• pp.157-166
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• 2024

Probability of decryption failure of a public key cryptography based on LWE(learning with errors) is determined by its architecture and parameter settings. Since large decryption failure probability leads to attacks[1] on scheme as well as degradation of performance, TiGER[2], a Ring-LWE(R)-based KEM proposed for the first round of KpqC, tried to reduce the decryption failure probability by using error correction code Xef and D2 encoding method. However, D'Anvers et al. has shown that the commonly assumed independence of each bit error is not established since in the case of an encryption scheme based on Ring-LWE(R) using an error correction code, there is error dependency which is not negligible[3]. In this paper, since TiGER does not consider the error dependency, we calcualte the decryption failure probability of TiGER by considering the error dependency. In addition, we found that the bit error probability is incorrectly calculated in TiGER, so we present the correct calculation.

• The KIPS Transactions:PartC
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• v.10C no.5
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• pp.585-594
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• 2003

Java card is one of promising smart card platform with java technology. Java card defines necessary packages and classes for Embedded device that have small memory such as smart card Jana card is compatible with EMV that is Industry specification standard and ISO-7816 that is international standard. However, Java card is not offers user authentication protocol. In this paper, We design and implement an user authentication protocol applicable wireless devices based on Java Card using standard 3GPP Specification (SMS), Java Card Specification (APDU), Cryptography and so on. Our Java Card user authentication techniques can possibly be applied to the area of M-Commerce, Wireless Security, E-Payment System, Mobile Internet, Global Position Service, Ubiquitous Computing and so on.

• The KIPS Transactions:PartC
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• v.12C no.1 s.97
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• pp.37-44
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• 2005

As wireless network was developed and Capability of Wireless Phone was increased, M-Commerce was activates In Wireless network environment. User Authentication and Security in E-Commerce Environment is very important, so Authentication Technology, such as WPKI and Hermes System, XML Digital Signature in Wire Network is studying. But if authentication systems was implemented heterogeneous, WPKI is difficult to implement the system, it's not interoperate with authentication system on wire internet, not support XML digital Signature. Hermes system also not interoperate with XML digital signature system. So our paper designed System that can interoperate among digital signature systems and XML document to apply XML digital signature technology on wire network to wireless network, and then implemented system that can XML digital signature to use Java Card.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.2
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• pp.293-298
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• 2009

In this contribution, a 193-bit elliptic curve cryptography coprocessor was implemented on an FPGA board. Optimized algorithms and numerical expressions which had been verified through C program simulation, should be analyzed again with HDL (hardware description language) such as Verilog, so that the verified ones could be modified to be applied directly to hardware implementation. The reason is that the characteristics of C programming language design is intrinsically different from the hardware design structure. The hardware IP which was double-checked in view of hardware structure together with algoritunic verification, was implemented on the Altera CycloneII FPGA device equipped with ARM9 microprocessor core, to a real chip prototype, using Altera embedded system development tool kit. The implemented finite field calculation IPs can be used as library modules as Elliptic Curve Cryptography finite field operations which has more than 193 bit key length.

• The Korean Journal of Air & Space Law and Policy
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• v.22 no.1
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• pp.55-74
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• 2007

When the People's Republic of China destroyed one of its own defunct meteorological satellites, the Fengyun-1C, at an altitude of some 865 km above the earth's surface, the PRC was accused of initiating, or at the very least risking an(other) arms race in outer space also. The test also gave rise to a few legal questions as to the permissibility of this test, and the broader permissibility of using space for military and other weapon-touting activities, Whilst the test cannot be considered to constitute a direct threat to international peace and security so as to invoke relevant legal principles and consequences in terms of the UN Charter for example, it highlights the importance of such clauses in international space law as requiring international cooperation and consultation, due regard for the interests of all other countries both on earth and in outer space, and the further development of general regimes of registration and space debris-prevention. From that perspective, the PRC violated international outer space law not so much by the test itself but by the accompanying lack of information, consultation and due regard for other states', and indeed mankind's, interests.