• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.2
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• pp.53-64
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• 2002

This paper describes a design of cryptographic processor that implements the AES (Advanced Encryption Standard) block cipher algorithm, "Rijndael". An iterative looping architecture using a single round block is adopted to minimize the hardware required. To achieve high throughput rate, a sub-pipeline stage is added by dividing the round function into two blocks, resulting that the second half of current round function and the first half of next round function are being simultaneously operated. The round block is implemented using 32-bit data path, so each sub-pipeline stage is executed for four clock cycles. The S-box, which is the dominant element of the round block in terms of required hardware resources, is designed using arithmetic circuit computing multiplicative inverse in GF($2^8$) rather than look-up table method, so that encryption and decryption can share the S-boxes. The round keys are generated by on-the-fly key scheduler. The crypto-processor designed in Verilog-HDL and synthesized using 0.25-$\mu\textrm{m}$ CMOS cell library consists of about 23,000 gates. Simulation results show that the critical path delay is about 8-ns and it can operate up to 120-MHz clock Sequency at 2.5-V supply. The designed core was verified using Xilinx FPGA board and test system.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.85-92
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• 2008

Strength of logs and round posts is compared and analyzed to estimate the strength of the incised Larix round posts treated with CCA in this paper. There is no significant difference in MOR of logs and round posts. However, in the incised Larix round posts treated with CCA MOE is decreased to about 9%, and there is 29% reduction in MOR as strength ratio is 0.71. When calculating the allowable bending stress of incised round type round posts, not in nominal 2-in timbers, an adjustment factor for MOE and bending strength is proposed as 0.91 and 0.71, respectively. Logs, round posts and the incised Larix round posts treated with CCA do not show significant difference in nail withdrawal load. There is almost no difference between incised Larix round posts treated with CCA and round posts in the shear strength of bolted joint. When calculating the allowable shear stress of bolted joint, it is conformed that considering the application of incising factor is not necessary.

• Journal of the Korean Mathematical Society
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• v.50 no.2
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• pp.231-240
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• 2013

We discuss the integrability of orthogonal almost complex structures on Riemannian products of even-dimensional round spheres and give a partial answer to the question raised by E. Calabi concerning the existence of complex structures on a product manifold of a round 2-sphere and of a round 4-sphere.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.854-859
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• 2000

When the round bar with step is twisted and bent, stress concentration is occurred in the irregular geometric parts. Two dimensional axisymmetric stress analysis is carried out according to the geometric change of the stress-concentrated part of round bar with step. Three dimensional cases are also investigated.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.264-267
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• 2002

This paper proposed a effective priority selection algorithm named weighted round-robin algorithm and show the implementation result of DMAC priority selection module using prosed weighted round-robin algorithm. I parameterize timing constraints of each functional module, which decide the effectiveness of system. Proposed weighted round-robin algorithm decide the most effective module for data transmission using parameterize timing constraints and update timing parameter of each module for next transmission module selection. I implement DMAC priority selection module using this weighted round-robin algorithm and can improve the timing effective for data transmission from memory to functional module or one functional module to another functional module.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.161-168
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• 2005

Tuber yield and content of general component and diosgenin which is a main bioactive property were investigated in order to determine the growth characteristics of round typed yam(Dioscorea opposita L.) and the potential of artificial culture at Suwon, Korea. Tubers of round yam were initiated to form at 60 days after planting and then enlargement of tubers lasted by 160 days after planting. Compared to short typed yam(108g), tuber weight of round yam was higher(127g) on the basis of dry weight at 200 days after planting. In comparison of general component between round yam and short yam, protein of round yam$(3.62\%)$ was higher than short yam$(2.10\%)$. Water content in round yam$(64.5\%)$ was lower in short yam$(79.4\%)$, indicating a higher dry weight ratio of round yam. Hardness of round yam was 2787.6 while short yam showed about two times higher hardness(4946.9). Lightness was higher in round yam(77.4). In tuber extracts analysis, diosgenin content was respectively $3.32\%$ in round yam and $2.61\%$ in short yam.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.50-62
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• 2004

Tuber yield and content of general component and diosgenin which is a main bioactive property were investigated in order to determine the growth characteristics of round typed yam(Dioscorea opposita L.) and the potential of artificial culture at Suwon, Korea. Tubers of round yam was initiated to form at 60 days after planting and then enlargement of tubers lasted by 160 days after planting. Compared to short typed yam(108g), tuber weight of round yam was higher(127g) on the basis of dry weight at 200 days after planting. In comparison of general component between round yam and short yam, protein of round yam(3.62%) was higher than short yam(2.10%). Water content in round yam(64.5%) was lower in short yam(79.4%), indicating a higher dry weight ratio of round yam. Hardness of round yam was 2787.6 while short yam showed about two times higher hardness(4946.9). Lightness was higher in round yam(77.4). In tuber extracts analysis, diosgenin content was respectively 3.32% in round yam and 2.61% in short yam.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.196-204
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• 2013

In this paper, a scheduling algorithm is proposed for military satellite networks to improve QoS(Quality of Service) based on WDRR(Weighted Deficit Round Robin) method. When the packet size that has been queued to be larger, the proposed scheme DWDRR(Dynamic WDRR) method give appropriate additional quantum using EWMA(Exponentially Weighted Moving Average). To demonstrate an usefulness of proposed algorithm using OPNET modeler that built the simulation environment, reliability and real-time availability of the proposed algorithm is analyzed. The simulation results show an availability of proposed scheme in terms of reduce queuing delay and packet drop rate compared and analyzed the existing algorithms WRR(Weighted Round Robin), DRR(Deficit Round Robin) and WDRR with DWDRR.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.2
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• pp.194-203
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• 1993

Quality Control programs for industrial hygiene laboratory have successfully been operated since the 1st round was initiated in April 1992. Three rounds have been completed. Overall analytical performance of participants was improved through a subsquent round. The first round had a large variation among analytical results of all participants, 26.34%~504.22% of coefficient of variation. But the variation of analytical performance in the 2nd and 3rd rounds decreased to 40.42%~52.55% and 10.74%~20.98%, respectively. The difference of analytical performance among participants was decreased by operation of subsquent round. By distribution of Running Performance Index (RPI), over 50% of participants belongs to Category 3 in the first round. The average percentage of participants assigned to Category 3 in the 2nd and 3rd round was decreased to 37.2%. A definite analytical performance improvement of participants seems to be obtained. "A" and "B" group have more participants assigned to Category 3 than those of "C" group through the distribution of RPI by group divided to similar participant. By the distribution of RPI all participants, the percent of participant being over 200 RPI in the 1st round was 43%~52%, but decreased to 9%~29% and 9%~27%, in the 2nd and 3rd round, respectively. These results mentioned above indicate that the analytical performance of all participants have been improved by subsquent Quality Control Program although newcomers joined and a few participants droped out. But, there are some participants with poor analytical performance. Industrial Health Research Institute (IHRI) will offer service such as education, communication and visitation to them, and improve quality of their analytical performance in the future.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.10
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• pp.3815-3833
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• 2021

MILP-based automatic search is the most common method in analyzing the security of cryptographic algorithms. However, this method brings many issues such as low efficiency due to the large size of the model, and the difficulty in finding the contradiction of the impossible differential distinguisher. To analyze the security of ESF algorithm, this paper introduces a simplified MILP-based search model of the differential distinguisher by reducing constrains of XOR and S-box operations, and variables by combining cyclic shift with its adjacent operations. Also, a new method to find contradictions of the impossible differential distinguisher is proposed by introducing temporary variables, which can avoid wrong and miss selection of contradictions. Based on a 9-round impossible differential distinguisher, 15-round attack of ESF can be achieved by extending forward and backward 3-round in single-key setting. Compared with existing results, the exact lower bound of differential active S-boxes in single-key setting for 10-round ESF are improved. Also, 2108 9-round impossible differential distinguishers in single-key setting and 14 12-round impossible differential distinguishers in related-key setting are obtained. Especially, the round of the discovered impossible differential distinguisher in related-key setting is the highest, and compared with the previous results, this attack achieves the highest round number in single-key setting.