• The KIPS Transactions:PartC
• /
• v.17C no.3
• /
• pp.233-242
• /
• 2010

In the recent years, power attacks were widely investigated, and so various countermeasures have been proposed. In the case of block ciphers, masking methods that blind the intermediate results in the algorithm computations(encryption, decryption) are well-known. In case of SEED block cipher, it uses 32 bit arithmetic addition and S-box operations as non-linear operations. Therefore the masking type conversion operations, which require some operating time and memory, are required to satisfy the masking method of all non-linear operations. In this paper, we propose a new masked S-boxes that can minimize the number of the masking type conversion operation. Moreover we construct just one masked S-box table and propose a new formula that can compute the other masked S-box's output by using this S-box table. Therefore the memory requirements for masked S-boxes are reduced to half of the existing masking method's one.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.6
• /
• pp.1064-1074
• /
• 1992

Eliminating the under-cut caused by interference between a mold and a product in designing a mold for in jection molding processes is a very important problem. In general, the under-cut problem can be avoided by side cores which are the principal members of a mold assembly. In this research, a procedure has been developed by which the side cores and the corresponding core and cavity plates of a mold are generated after identifying the mold faces preventing product faces from moving while being discharged. The characteristic features of the procedure suggested in this paper are as follows. One is that the interference faces between the product and the mold are derived only from the core plate(or cavity plate) alone without considering the product together. The other is that the algorithm in the designing of side cores and modifying molds, is very efficient because it uses Euler operations instead of Boolean operations.

• Journal of the Korean Society for information Management
• /
• v.16 no.1
• /
• pp.7-30
• /
• 1999

This study is to develop effective document ranking algorithms in the P-norm retrieval system which can be implemented to the Boolean retrieval system without major difficulties by using non-statistical term weights based on document structure. Also, it is to enhance the performance by introducing the rank adjustment process which rearranges the ranks of retrieved documents according to the similarity between the top ranked documents and the rest of them. Of the non-statistical term weight algorithms, this study uses field weight and term pair distance weight. In the rank adjustment process, five retrieval experiments were performed, ranging between the case of using one record for the similarity measurement and the case of using first five records. It is proved that non-statistical term weights are highly effective and the rank adjustment process enhance the performance further.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.8
• /
• pp.361-366
• /
• 2017

For two given logical expressions and, when expression contains the same part of the logical expression as expression, substituting for that part of expression is called a substituted logic expression. If a substituted relation is established between the logical expressions, there is an advantage in that the number of literals used in the whole logical expression can be greatly reduced. However, if the substituted relation is not established, there is no simplification effect obtained from the substituted expression. Previous methods proposed a way to find substituted relations between logical expressions for the given logical expressions themselves, and to calculate substituted expressions if only substitution is possible. In this paper, a new method for performing substitution with addition and revision of logic terms is proposed in order to perform substitution, even though there is no substituted relation between two logic expressions. The proposed method is efficiently implemented using a matrix that finds terms to be added. Then, by covering the matrix that has added terms, substituted logic expressions are found. Experiment results show that the proposed method for several benchmark circuits can reduce the number of literals, compared to existing synthesis tools.

• Journal of KIISE:Software and Applications
• /
• v.27 no.2
• /
• pp.168-179
• /
• 2000

In reusable component retrieval systems with facet-based schemes, facet queries are generally used for representing the characteristics of components relevant to users. This paper proposes an expanded facet query equipped with an object-based thesaurus to precisely formulate user's intents. To evaluate the query, a component retrieval system is also designed and implemented. For exactly retrieving the components, user's query should include relevant facet values capable of fully specifying their characteristics. However, simply listing a series of facet values directly inputted by users, conventional queries fails to precisely represent user's intents. Our query, called expanded facet query, employs fuzzy boolean operators and object-based thesaurus; the former logically expresses the fuzzy connectives between facet queries and required components, whereas the latter helps users appropriately select the specific facet values into the query. A thesaurus query is provided to recommend the relevant facet values with their fuzzy degrees from the thesaurus as well. Furthermore, our retrieval system can automatically formulate queries with the recommended facet values, if necessary.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.6
• /
• pp.993-998
• /
• 2006

We earlier suggested a hierarchical regulatory network using defined modeling symbols and weights in order to improve the flux balance analysis (FBA) with regulatory events that were represented by if-then rules and Boolean logic. In the present study, the simulation results of the models, which were developed and improved from the previou model by incorporating a hierarchical regulatory network into the FBA, were compared with the experimental outcome of an aerobic batch growth of E. coli on glucose and tryptophan. From the experimental result, a diauxic growth curve was observed, reflecting growth resumption, when tryptophan was used as an alternativee after the supply of glucose was exhausted. The model parameters, the initial concentration of substrates (0.92 mM glucose and 1 mM tryptophan), cell density (0.0086 g biomass/1), the maximal uptake rates of substrates (5.4 mmol glucose/g DCW h and 1.32 mmol tryptophan/g DCW h), and lag time (0.32 h) were derived from the experimental data for more accurate prediction. The simulation results agreed with the experimental outcome of the temporal profiles of cell density and glucose, and tryptophan concentrations.

• Journal of the Korean Society for information Management
• /
• v.23 no.2
• /
• pp.61-79
• /
• 2006

To come up with the recommendations to improve the patent & trademark retrieval efficiency, 100,016 patent & trademark search requests by 17,559 unique users over a period of 193 days were analyzed. By analyzing 2,202 multi-query sessions, where one user issuing two or more queries consecutively, we discovered a number of retrieval efficiency improvements clues. The session analysis result also led to suggestions for new system features to help users reformulating queries. The patent & trademark retrieval users were found to be similar to the typical web users in certain aspects especially in issuing short queries. However, we also found that the patent & trademark retrieval users used Boolean operators more than the typical web search users. By analyzing the multi-query sessions, we found that the users had five intentions in reformulating queries such as paraphrasing, specialization, generalization, alternation, and interruption, which were also used by the web search engine users.

• Journal of the Korean Society for information Management
• /
• v.30 no.3
• /
• pp.23-48
• /
• 2013

This study compared and analyzed 15 CBMR (Content-based Music Retrieval) systems accessible on the web in terms of DB size and type, query type, access point, input and output type, and search functions, with reviewing features of music information and techniques used for transforming or transcribing of music sources, extracting and segmenting melodies, extracting and indexing features of music, and matching algorithms for CBMR systems. Application of text information retrieval techniques such as inverted indexing, N-gram indexing, Boolean search, truncation, keyword and phrase search, normalization, filtering, browsing, exact matching, similarity measure using edit distance, sorting, etc. to enhancing the CBMR; effort for increasing DB size and usability; and problems in extracting melodies, deleting stop notes in queries, and using solfege as pitch information were found as the results of analysis.

• The Journal of the Korea Contents Association
• /
• v.9 no.11
• /
• pp.54-62
• /
• 2009

To avoid the redundant investment on the project selection process, it is necessary to check whether the submitted research topics have been proposed or carried out at other institutions before. This is possible through the search engines adopted by the keyword matching algorithm which is based on boolean techniques in national-sized research results database. Even though the accuracy and speed of information retrieval have been improved, they still have fundamental limits caused by keyword matching. This paper examines implemented TFIDF-based algorithm, and shows an experiment in search engine to retrieve and give the order of priority for similar and redundant documents compared with research proposals, In addition to generic TFIDF algorithm, feature weighting and K-Nearest Neighbors classification methods are implemented in this algorithm. The documents are extracted from NDSL(National Digital Science Library) web directory service to test the algorithm.

• The Transactions of the Korea Information Processing Society
• /
• v.3 no.2
• /
• pp.381-389
• /
• 1996

A simple modification of the standard back-propagation algorithm to eliminate redundant connections(weights and biases) is described. It was motivated by speculations from the distribution of the magnitudes of the weights and the biases, analysis of the classification boundary, and the nonlinearity of the sigmoid function. After initial training, this algorithm eliminates all connections of which magnitude is below a threshold by setting them to zero. The algorithm then conducts retraining in which all weights and biases are adjusted to allow important ones to recover. In studies with Boolean functions, the algorithm reconstructed the theoretical minimum architecture and eliminated the connections which are not necessary to solve the functions. For simulated random signal classification problems, the algorithm produced the result which is consistent with the idea that easier problems require simpler networks and yield lower misclassification rates. Furthermore, in comparison, our algorithm produced better generalization than the standard algorithm by reducing over fitting and pattern memorization problems.