• International Journal of Computer Science & Network Security
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• 제21권9호
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• pp.1-10
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• 2021

The Internet of things (IoT) is the main advancement in data processing and communication technologies. In IoT, intelligent devices play an exciting role in wireless communication. Although, sensor nodes are low-cost devices for communication and data gathering. However, sensor nodes are more vulnerable to different security threats because these nodes have continuous access to the internet. Therefore, the multiparty security credential-based key generation mechanism provides effective security against several attacks. The key generation-based methods are implemented at sensor nodes, edge nodes, and also at server nodes for secure communication. The main challenging issue in a collaborative key generation scheme is the extensive multiplication. When the number of parties increased the multiplications are more complex. Thus, the computational cost of batch key and multiparty key-based schemes is high. This paper presents a Secure Multipart Key Distribution scheme (SMKD) that provides secure communication among the nodes by generating a multiparty secure key for communication. In this paper, we provide node authentication and session key generation mechanism among mobile nodes, head nodes, and trusted servers. We analyzed the achievements of the SMKD scheme against SPPDA, PPDAS, and PFDA schemes. Thus, the simulation environment is established by employing an NS 2. Simulation results prove that the performance of SMKD is better in terms of communication cost, computational cost, and energy consumption.

• 정보보호학회논문지
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• 제12권2호
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• pp.89-100
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• 2002

본 논문에서는 안전한 그룹통신을 위한 그룹키 관리 기법을 기반으로 이동네트워크 환경에서의 그룹키 관리 구조와 멤버의 인종과 키 설정을 위한 프로토콜을 제안한다. 기존의 대부분의 그룹키 관리기법들이 초기의 키 서버와 멤버간의 안전한 공유키 설정을 위해 공개키 기반의 인증서 교환을 이용하였으나, 본 논문에서는 인증서의 교환과 검증으로 인한 대역폭 소모의 효율성을 위해 ICPK를 이용해서 그룹 내에서의 멤버의 인증과 키 교환에 이용하도록 한다. 또한, 전체 그룹을 이동호스트들에 대한 셀 그룹과 셀 그룹 관리자들에 대한 제어그룹으로 구분하여 셀 그룹마다 셀 그룹 관리자가 관리함으로써 멤버십의 변경으로 인한 영향을 지역적으로 한정시킨다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권12호
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• pp.4275-4291
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• 2021

With the unprecedented growth of textual information on the Internet, an efficient automatic summarization system has become an urgent need. Recently, the neural network models based on the encoder-decoder with an attention mechanism have demonstrated powerful capabilities in the sentence summarization task. However, for paragraphs or longer document summarization, these models fail to mine the core information in the input text, which leads to information loss and repetitions. In this paper, we propose an abstractive document summarization method by applying guidance signals of key sentences to the encoder based on the hierarchical encoder-decoder architecture, denoted as KI-HABS. Specifically, we first train an extractor to extract key sentences in the input document by the hierarchical bidirectional GRU. Then, we encode the key sentences to the key information representation in the sentence level. Finally, we adopt key information representation guided selective encoding strategies to filter source information, which establishes a connection between the key sentences and the document. We use the CNN/Daily Mail and Gigaword datasets to evaluate our model. The experimental results demonstrate that our method generates more informative and concise summaries, achieving better performance than the competitive models.

• 정보처리학회논문지C
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• 제11C권2호
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• pp.149-156
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• 2004

브로드캐스트 암호화 기법은 공개된 네트워크 상에서 멀티미디어, 소프트웨어, 유료 TV 등의 디지털 정보들을 전송하는데 적용되고 있다. 브로드캐스트 암호화 기법에서는 중요한 것은 오직 사전에 허가된 사용자만이 디지털 정보를 얻을 수 있어야 한다는 것이다. 브로트캐스트 메시지가 전송되면 권한이 있는 사용자들은 자신이 사전에 부여받은 개인키를 이용하여 디지털 정보를 얻게 된다. 이와 같이 사용자가 디지털 정보를 획득하기 위해서는 브로드캐스터가 키를 생성하고 분배하는 과정이 필요하다. 또한 사용자가 탈퇴나 새로운 가입 시에 효율적인 키 갱신이 필요하게 된다. 이에 본 논문에서는 효율적인 키 생성과 분배, 키 갱신 방법에 대해 소개한다. 제안 방식은 두 가지 기법을 이용하는데, 하나는 서버가 사용자의 동의 없이 사용자를 예측하여 키를 생성하는 방법이고 다른 하나는 서버와 사용자가 서로 동의하여 키를 생성하는 방법이다. 두 제안 방식의 장점은 수신자는 하나의 비밀키를 이용하여 브로드캐스트되는 메시지를 복호화 할 수 있으며 후에 키가 갱신된다 하더라도 하나의 정보만을 이용하여 효과적으로 갱신이 가능하다.

• The Plant Pathology Journal
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• 제25권4호
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• pp.429-432
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• 2009

An unreported disease of apricot was observed in orchards in Zhejiang province, China. Symptoms started as water soaked lesions on the fruit surface. Later, water-soaked areas developed and spread to the entire fruit, resulting in soft rot of the whole fruit. The causal organism isolated from symptomatic fruits was identified as Burkholderia cepacia based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 16S rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto fruits of apricot. In addition, European plum, Japanese plum, nectarine and kiwifruit were susceptible to the B. cepacia pathogen. However, the B. cepacia pathogen failed to cause any visible symptoms when it was inoculated onto 16 other fruits. This is the first report of a bacterial disease of apricot caused by B. cepacia in China.

• 대한치과기공학회지
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• 제34권4호
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• pp.457-469
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• 2012

Purpose: The purpose of this study is analyzing how much students of dental technology possess core competencies and cognition between dental technicians and students. Methods: The subjects of this study were dental technicians, dental technology students and a self-administered structured questionnaire survey wax conducted for 428 selected people. Collected data were analyzed using SPSS Win 20.0 statistics program and analysis techniques include the frequency, t-test, One-way ANOVA. Results: The results of the survey are as follows. The cognition of key competency according to the gender in the students showed differences in interpersonal ability, information ability and the requirement of key competency according to the gender in the students showed differences in speaking ability, listening ability, problem solving ability. The cognition of key competency according to the grade in the students showed difference in speaking ability, listening ability and the requirement of key competency according to the grade in the students showed difference in comprehension of organization ability. The speaking ability is the lowest in the cognition of key competency according to the gender, grade, experience of clinical training in the students and the skill ability is the highest in the requirement of key competency according to the gender, experience of clinical training in the students. The cognition of key competency according to the career in the dental technicians showed difference in problem solving ability, self-regulation and self-development ability, skill ability and the requirement of key competency according to the career in the dental technicians showed difference in writing ability. The cognition of key competency according to the educational background in the dental technicians showed difference in comprehension of organization ability. The foreign language ability is the lowest in the cognition of key competency according to the career, job in the dental technicians and the skill ability is the highest and the math ability is th lowest in the requirement of key competency according to the career, place of employment in the dental technician. Conclusion: This study can be used as basic data for dental technology that are available not only to field-oriented disciplines but also to overall higher education fields which aim to strengthen key competency.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.155-161
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• 2009

Mammal microsomal glutathione transferase 1 (MGST1) can conjugate many toxic or carcinogenic substances and depress oxidative stress. In this study, Chicken MGST1 and its variants were cloned for the first time and were composed of 956 or 944 nucleotides. The 12 nt deletion in the exon 2 did not alter the GT-AG rule and the ORFs for the two MGST1 variants were the same, which both comprised 465 nucletides and encoded a peptide with 155 amino acids. It was found that the two different splice variants identified using RT-PCR expressed in all three organs investigated of Dwarf Brown Chicken, namely liver, spleen and shell gland. Moreover, the expression level of MGST1 mRNA in the liver of Dwarf Brown chickens was the highest (p<0.01), and there were no significant differences between the spleen and the shell gland. These results provide a base for studying the biological function of Chicken MGST1.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1608-1611
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• 2009

Here the hydrogen passivation treatment has been adopted to enhance the performance of poly-Si crystallized by YAG laser annealing (LA poly-Si). We have investigated the effects of passivation time, passivation power and passivation temperature on the hall mobility of the LA poly-Si and analyzed the mechanism of the hydrogen passivation preliminary. It has been found that the quality of the poly-Si annealed by YAG laser could be improved after proper hydrogen plasma treatment.

• 한국정보과학회논문지:정보통신
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• 제30권3호
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• pp.371-376
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• 2003

무선 인터넷이 활성화되면서 E-Commerce에서 M-Commerce로의 전환이 빨라지고 있으며, 많은 서비스 제공자들은 무선 기술을 이용해 다양한 M-Commerce 서비스를 사용자들에게 제공하고 있다. M-Commerce가 활성화되면서 보안 프로토콜에 대한 중요성이 인식되고 있다. 특히, 무선상에서 이루어지는 WAKE(Wireless Authentication and Key Establishment) 프로토콜은 M-Commerce를 수행하고자 하는 사용자와 서비스 제공자가 필수적으로 거쳐야 하는 것으로 그 중요성은 매우 크다고 할 수 있다. 키 복구 기술은 사용자가 키를 유실하거나 또는 암호를 불법적으로 사용하였을 경우 키 복구를 통해서 키에 대한 접근을 할 수 있게 해주는 키 관리의 한 부분이다. WAKE 프로토콜에 키 복구 기능을 지원하고자 하는 노력은 ASPeCT 프로젝트에 의해서 처음으로 시도되었다. 이후 다양한 WAKE 키 복구 프로토콜이 제안되었다. 본 논문에서는 기존에 제안되었던 WAKE 키 복구 프로토콜의 문제점을 알아보고 이들을 해결하는 새로운 WAKE 키 복구 프로토콜을 제안한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권9호
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• pp.3274-3297
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• 2021

Permission delegation is an important research issue in access control. It allows a user to delegate some of his permissions to others to reduce his workload, or enables others to complete some tasks on his behalf when he is unavailable to do so. As an ideal solution for controlling read access on outsourced data objects on the cloud, Ciphertext-Policy Attribute-Based Encryption (CP-ABE) has attracted much attention. Some existing CP-ABE schemes handle the read permission delegation through the delegation of the user's private key to others. Still, these schemes lack the further consideration of granularity and traceability of the permission delegation. To this end, this article proposes a flexible and fine-grained CP-ABE key delegation approach that supports white-box traceability. In this approach, the key delegator first examines the relations between the data objects, read permission thereof that he intends to delegate, and the attributes associated with the access policies of these data objects. Then he chooses a minimal attribute set from his attributes according to the principle of least privilege. He constructs the delegation key with the minimal attribute set. Thus, we can achieve the shortest delegation key and minimize the time of key delegation under the premise of guaranteeing the delegator's access control requirement. The Key Generation Center (KGC) then embeds the delegatee's identity into the key to trace the route of the delegation key. Our approach prevents the delegatee from combining his existing key with the new delegation key to access unauthorized data objects. Theoretical analysis and test results show that our approach helps the KGC transfer some of its burdensome key generation tasks to regular users (delegators) to accommodate more users.