• Investigative Magnetic Resonance Imaging
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• v.3 no.2
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• pp.154-158
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• 1999

Purpose : The purpose of this study was to find the optimum TE value for enhancing $T_2^{*}$ weighting effect and minimizing the SNR degradation and to compare the BOLD effects according to the changes of TE in 1.5T and 3.0T MRI systems. Materials and Methods : Healthy normal volunteers (eight males and two females with 24-38 years old) participated in this study. Each volunteer was asked to perform a simple finger-tapping task (sequential opposition of thumb to each of the other four fingers) with right hand with a mean frequency of about 2Hz. The stimulus was initially off for 3 images and was then alternatively switched on and off for 2 cycles of 6 images. Images were acquired on the 1.5T and 3.0T MRI with the FLASH (fast low angle shot) pulse sequence (TR : 100ms, FA : $20^{\circ}$, FOV : 230mm) that was used with 26, 36, 46, 56, 66, 76ms of TE times in 1.5T and 16, 26, 36, 46, 56, 66ms of TE in 3.0T MRI system. After the completion of scan, MR images were transferred into a PC and processed with a home-made analysis program based on the correlation coefficient method with the threshold value of 0.45. To search for the optimum TE value in fMRI, the difference between the activation and the rest by the susceptibility change for each TE was used in 1.5T and 3.0T respectively. In addition, the functional $T_2^{*}$ map was calculated to quantify susceptibility change. Results : The calculated optimum TE for fMRI was $61.89{\pm}2.68$ at 1.5T and $47.64{\pm}13.34$ at 3.0T. The maximum percentage of signal intensity change due to the susceptibility effect inactivation region was 3.36% at TE 66ms in 1.5T 10.05% at TE 46ms in 3.0T, respectively. The signal intensity change of 3.0T was about 3 times bigger than of 1.5T. The calculated optimum TE value was consistent with TE values which were obtained from the maximum signal change for each TE. Conclusion : In this study, the 3.0T MRI was clearly more sensitive, about three times bigger than the 1.5T in detecting the susceptibility due to the deoxyhemoglobin level change in the functional MR imaging. So the 3.0T fMRI I ore useful than 1.5T.

• The KIPS Transactions:PartB
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• v.9B no.6
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• pp.783-790
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• 2002

This paper proposes a fuzzy Pr/T net representation of interval-valued fuzzy set reasoning, where fuzzy production rules are used for knowledge representation, and the belief of fuzzy production rules are represented by interval-valued fuzzy sets. The presented interval-valued fuzzy reasoning algorithm is much closer to human intuition and reasoning than other methods because this algorithm uses the proper belief evaluation functions according to fuzzy concepts in fuzzy production rules.

• Progress in Medical Physics
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• v.20 no.4
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• pp.298-307
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• 2009

By using the MR T2 map technique, this study intends, first, to measure the change of T2 values of cartilage between healthy people and patients with osteoarthritis and, second, to assess the form and the damage of cartilage in the knee-joint, through which this study would consider the utility of the T2 map technique. Thirty healthy people were selected based on their clinical history and current status and another thirty patients with osteoarthritis of the knee who were screened by simple X-ray from November 2007 to December 2008 were selected. Their T2 Spin Echo (SE hereafter) images for the cartilage of the knee joint were collected by using the T2 SE sequence, one of the multi-echo methods (TR: 1,000 ms; TE values: 6.5, 13, 19.5, 26, 32.5. 40, 45.5, 52). Based on these images, the changes in the signal intensity (SI hereafter) for each section of the cartilage of the knee joint were measured, which yielded average values of T2 through the Origin 7.0 Professional (Northampton, MA 01060 USA). With these T2s, the independent samples T-test was performed by SPSS Window version 12.0 to run the quantitative analysis and to test the statistical significance between the healthy group and the patient group. Closely looking at T2 values for each anterior and lateral articular cartilage of the sagittal plane and the coronal plane, in the sagittal plane, the average T2 of the femoral cartilage in the patient group with arthritis of the knee ($42.22{\pm}2.91$) was higher than the average T2 of the healthy group ($36.26{\pm}5.01$). Also, the average T2 of the tibial cartilage in the patient group ($43.83{\pm}1.43$) was higher than the average T2 in the healthy group ($36.45{\pm}3.15$). In the case of the coronal plane, the average T2 of the medial femoral cartilage in the patient group ($45.65{\pm}7.10$) was higher than the healthy group ($36.49{\pm}8.41$) and so did the average T2 of the anterior tibial cartilage (i.e., $44.46{\pm}3.44$ for the patient group vs. $37.61{\pm}1.97$ for the healthy group). As for the lateral femoral cartilage in the coronal plane, the patient group displayed the higher T2 ($43.41{\pm}4.99$) than the healthy group did ($37.64{\pm}4.02$) and this tendency was similar in the lateral tibial cartilage (i.e., $43.78{\pm}8.08$ for the patient group vs. $36.62{\pm}7.81$ for the healthy group). Along with the morphological MR imaging technique previously used, the T2 map technique seems to help patients with cartilage problems, in particular, those with the arthritis of the knee for early diagnosis by quantitatively analyzing the structural and functional changes of the cartilage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1180-1185
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• 2009

In this paper, the Low Pass Filter (LPF) using the equivalent circuit of T-junction microstrip line is proposed. And we derived the formulas for lumped-elements of the equivalent circuit of T-junction microstrip line to solve the frequency shift characteristic. T-junction microstrip line is de-embedded by Electromagnetic simulation tool and exact lumped element value of T-junction microstrip line is calculated by the equation of Z-parameter. We can get excellent agreement between lumped-element LPF frequency response and transmission line LPF frequency response.

• Journal of the Korean Society for information Management
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• v.30 no.4
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• pp.111-131
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• 2013

This study describes the meaning of and the formula for Kor-$h_T$, which is a modified index built on the tapered h-index by applying 'the ranking according to the number of citations of journals'. This study evaluated the de-duplication rate of index values of Kor-$h_T$ and analyzed the change in the correlation between the index values and evaluation elements using the Korea Citation Index data from 2008 to 2010. Kor-$h_T$ is compared with h-index, tapered h-index, and IF. As a result, Kor-$h_T$ appeared to be superior to other indexes on de-duplication rate. It is also shown that there is a very strong positive correlation between the evaluation elements, the number of citations and the number of articles of journals, and the index values of Kor-$h_T$.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.1041-1050
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• 2005

This study was conducted to investigate the quality characteristics of seasoned pork prepared by Korean traditional 4 types seasoning such as soy sauce (T1); Kimchi sauce (T2); pickled shrimps sauce (T3) and onion sauce (T4). The samples were seasoned by the proportion of meat to seasonings (1:1). The seasoned samples were aged at $1{\pm}1^{\circ}C$ for 30 days. The results obtained were as follows; pH of T3 was higher (p<0.05) than other treatments during aging periods. Saccharinity and salinity were higher in T1. Except T3, water holding capacity (WHC) have no significantly (p>0.05) different during the aging. Shear force and Volatile basic nitrogen (VBN) were increased in T1 and T4 with aging periods. TBARS have no significantly (p>0.05) different in all treatments at the 1 day of aging, however T1 was significantly higher (p<0.05) compared with other treatments after 10 days of aging. In surface meat color, a* and b* were higher in T2 and lower in T4 with aging periods. In inner meat color, L* was decreased in all treatments with aging periods, however T4 was no significantly (p>0.05) different during aging periods. a* and b* were increased with aging periods in all treatments. Total plate counts was increased at the 10 days of aging and decreased at the end of aging. Escherichia coli of T1, T2 and T3 were decreased with aging periods, however T4 was significantly (p<0.05) increased with aging periods. Lactobacilli spp. of T2 and T3 were higher than other treatments at the beginning of aging. In sensory evaluation, T4 was higher at the beginning of aging, however T1 and T3 were increased sensory evaluation value with aging periods.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.6
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• pp.1037-1044
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• 2014

A (t,n) threshold secret sharing scheme is the scheme which allows a trusted party to distribute the shares among n participants in such a way that any t of them can recover the original secret, but any group knowing only t-1 or fewer shares can not. Recently, Eslami et al. and Tadayon et al. proposed threshold multi-secret sharing schemes, respectively. They proposed that their schemes don't require secure channels. But, without secure channels in their schemes, everyone can get the shares and find the secrets. The proposed scheme does not use secure channels and only t participants can solve the equations of the system from the delivered share shadows and find the secrets.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.74-80
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• 2011

The objective of this study was to determine the shelf-life effects and residual nitrite content of emulsified sausages added with pine needles during cold storage. The sausage consisted of four types: no pine needles added (control), pine needle juice added (T1), ethanol extract of pine needles added (T2), and boiling extract of pine needles added (T3). Each sausage type was tested in triplicate and assigned to one of four storage periods: 0, 10, 20, or 30 d. As storage time increased, the presence of pine needles resulted in decreased pH, meat color (CIE $L^*$, $a^*$ and $b^*$), residual nitrite value, and increased thiobarbituric acid reactive substances (TBARS) values and total plate counts (TPC). Values for pH, TBARS, residual nitrite, total plate counts and CIE $L^*$ and $a^*$ decreased significantly with added pine needles relative to the control (p<0.05). In particular, T2 was significantly (p<0.05) more effective for delaying lipid oxidation than the other treatment groups. In conclusion, the results demonstrate that adding an ethanol extract of pine needles (T2) to emulsified sausages tended to improve antioxidative and antimicrobial effects and reduce residual nitrite content during storage compared to the other treatment groups.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.122-128
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• 2011

This study was conducted to investigate the antioxidant effects, total plate count (TPC), and residual nitrite content of emulsified sausage with added mugwort during cold storage. The sausages were of five types: nothing added (control), mugwort powder added (T1), mugwort juice added (T2), mugwort ethanol extract added (T3), and mugwort hot water extract added (T4). Each sausage type was tested in triplicate and assigned to one of five storage periods: 0, 1, 2, 3, or 4 wk. As storage time increased, the presence of mugwort resulted in decreased pH, residual nitrite content, and meat color (CIE $L^*$ and $b^*$) and increased thiobarbituric acid reactive substance (TBARS) and TPC values. Values for pH, TBARS, residual nitrite, and TPC decreased significantly after adding mugwort compared with the control (p<0.05). Among all treatments, T3 was significantly (p<0.05) more effective in delaying lipid oxidation and microbial activity. The CIE $L^*$ and $b^*$ decreased significantly with the addition of mugwort relative to the control. In conclusion, the results demonstrate that adding an ethanol extract of mugwort (T3) to emulsified sausages tended to improve antioxidant and antimicrobial effects and residual nitrite content during storage compared to the other treatment groups.

• The KIPS Transactions:PartB
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• v.10B no.7
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• pp.757-768
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• 2003

This paper proposes a weighted fuzzy reasoning algorithm for rule-based systems based on weighted fuzzy Pr/T nets, where the certainty factors of the fuzzy production rules, the truth values of the predicates appearing in the rules and the weights representing the importance of the predicates are represented by the fuzzy numbers. The proposed algorithm is more flexible and much closer to human intuition and reasoning than other methods : $\circled1$ calculate the certainty factors using by the simple min and max operations based on the only certainty factors of the fuzzy production rules without the weights of the predicates[10] : $\circled2$ evaluate the belief of the fuzzy production rules using by the belief evaluation functions according to fuzzy concepts in the fuzzy rules without the weights of the predicates[12], because this algorithm uses the weights representing the importance of the predicates in the fuzzy production rules.