• Korean Journal of Environmental Agriculture
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• v.38 no.1
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• pp.47-53
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• 2019

BACKGROUND: This experiment was conducted to examine the effects of organic Se concentration and the number of foliar applications on growth characteristics and Se content in rice. METHODS AND RESULTS: A series of multiple foliar applications were performed at (1) 3 times (maximum tillering stage + booting stage + heading stage), (2) 4 times I (effective tillering stage + maximum tillering stage + booting stage + heading stage), (3) 4 times II (maximum tillering stage + booting stage + heading stage + grain filling stage) according to the development stage. Each set of the foliar application plots was treated with 0, 10, 20, 40, 60, 100 ppm of Se and with mixed pesticide ($P^*$ + Se 40 ppm) in which the treatment time was the same as that of the treatment 4 times II. The total cultivation period of rice was 184 days. Se contents in rice (brown rice, white rice) were analyzed by ICP. CONCLUSION: The number of grains per head tended to decrease with increasing concentrations of organic Se in all treatments. However, number of panicles per hill did not show statically significant differences between the 3 times and 4 times I treatments. The grain yield decreased with the 3 times and 4 times II, but there was no significant difference in 4 times I. Se content in brown rice was the highest at 100 ppm Se (5268.64) treatment and lowest at 10 ppm Se ($1269.19{\mu}g{\cdot}kg^{-1}$) treatment. Se content in the polished rice was the highest at 100 ppm Se (5047.33) treatment and lowest at 10 ppm Se ($885.05{\mu}g{\cdot}kg^{-1}$) treatment. The higher selenium was treated, the higher Se content was found in the rice (brown rice, polished rice).

• 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.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.1
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• pp.25-33
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• 2001

In 1998, A. Young and M. Yung introduced the concept of ARC that conjugates functionalities of a typical PKI with the ability to escrow privte keys of the system users. Also in 1999, P. Paillier and M. Yung proposed a new notion - called SE-PKI -which presents other additional advantages beyond ARC. But SE-PKI system uses only one escrow agent. The storage of users secret information at a single agent can make it significant point of attack and arouse controversy about invasion of privacy. This paper presents SE-PKI key recovery system that multiple escrow agents can participate in it. Also, in our system, escrow agents can\`t recover user\`s ciphertext.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.1
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• pp.35-42
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• 2001

The primitive polynomial on GF(q) is used in the area of the scrambler, the error correcting code and decode, the random generator and the cipher, etc. The algorithm that generates efficiently the primitive polynomial on GF(q) was proposed by A.D. Porto. The algorithm is a method that generates the sequence of the primitive polynomial by repeating to find another primitive polynomial with a known primitive polynomial. In this paper, we propose the algorithm that is improved in the A.D. Porto algorithm. The running rime of the A.D. Porto a1gorithm is O($\textrm{km}^2$), the running time of the improved algorithm is 0(m(m+k)). Here, k is gcd(k, $q^m$-1). When we find the primitive polynomial with m odor, it is efficient that we use the improved algorithm in the condition k, m>>1.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.5
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• pp.129-136
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• 2003

A representative payment broker system is SET and one of its signature shcemes is a dual digital signature scheme. A dual digital signature scheme expose neither user's payment information(credit card number etc.) to merchandiser, nor user's order information to bank So it keeps user's Privacy safe. The digital signature scheme like this is being necessary as E-commerce is revitalized. But a dual digital signature of SET is not appropriate for wireless environments because it needs so many computations and communications. In this paper, we propose a signcryption scheme that generates a polynomial using a payment information for merchandiser and an order information for bank in order to reduce communications. We analyze the problem of existing signcryption schemes and dual digital signature schemes. Also we analyze the security properties of the proposed scheme.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.1
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• pp.41-55
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• 2005

A group key agreement protocol allows a group of user to share a key which may later be used to achieve certain cryptographic goals. In this paper, we propose a new scalable two-round ID-based group key agreement protocol which would be well fit to a Pay-TV system, additionally. to the fields of internet stock quotes, audio and music deliveries, software updates and the like. Our protocol improves the three round poop key agreement protocol of Nam et al., resulting in upgrading the computational efficiency by using the batch verification technique in pairing-based cryptography. Also our protocol simplifies the key agreement procedures by utilizing ID-based system. We prove the security of our protocol under the Computational Diffie-Hellman assumption and the Bilinear Decisional Diffie-Hellman assumption. Also we analyze its efficiency.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.2
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• pp.145-185
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• 2007

A resident registration number is used to confirm and prove his/her identity in a government/non-governmental agency. It is a essential requirement to become the registered member on internet website in Korea. It is serious problem that the resident registration number and name are outflowed in internet and misused by others. So the MIC(Ministry of Information and Communication) in Korea plans and operates the identification system using I-PIN that integrate 5 alternative methods of resident registration number. In this paper, we analyze the problem about the method of 5 I-PIN services and show the security analysis on the implementation vulnerabilities of I-PIN services. we also analyze 17 websites that provides identification system using I-PIN. Finally, we analyze the overall problem of I-PIN service and propose the countermeasure about the problem.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.6
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• pp.99-119
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• 2007

The USB flash drive is common used for portable storage. That is able to store large data and transfer data quickly and carry simply. But when you lose your USB flash drive without any security function in use, all stored data will be exposed. So the new USB flash drive supported security function was invented to compensate for the problem. In this paper, we analyze vulnerability of 6 control access program for secure USB flash drives. And we show that exposed password on communication between secure USB flash drive and PC. Also we show the vulnerability of misapplication for initialization. Further we develop a protection profile for secure USB flash drive based on the common criteria version 3.1. Finally, we examine possible threat of 6 secure USB flash drives and supports of security objectives which derived from protection profile.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.1
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• pp.133-138
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• 2007

As a formal document that expresses a set of security requirements for IT products that meets specific consumer needs in the ISO/IEC 15408(CC, Common Criteria) evaluation, protection profiles are developing by many national agencies and companies recently. Since a protection profile is a criteria for security evaluation when the IT systems and products are introduced, the importance of the protection profile is increasing. However, developing protection profiles are still difficult due to lack of detailed methodology and guidance to analyze security environments or to derive security requirements. In this paper, we analyze foreign instances of developing protection profiles and propose a methodology for deriving security requirements through analyzing the TOE security environment.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.1
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• pp.97-101
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• 2007

The purpose of DRM is to protect the copyrights of content providers and to enable only designated users to access digital contents. From the consumers' point of view, they have a tendency to go against complex and confusing limitations. Moreover, consumers' rights of use of the content obtained legally were frequently harmed by arbitrary limitations. The concept of Authorized Domain (AD) was presented to remove such problems. However, the previous work on authorized domain has two problems. The first is that it requires a rather expensive revocation mechanism for withdraw process. The second is that the modules still can play contents which are previously obtained even though they are currently out of the authorized domain. On the contrary, our scheme presents the content from being played by modules which are out of the domain for better security. Furthermore our scheme does not need to maintain a revocation list and prevent replay attack.