• Title/Summary/Keyword: Block Division

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Proposal of Kiosk Payment Security System using Public Blockchain (솔라나 블록체인을 이용한 키오스크 결제 데이터 보안 시스템 제안)

  • Kim, Seong-Heon;Kang, hyeok;Lee, Keun-ho
    • Journal of Internet of Things and Convergence
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    • v.8 no.5
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    • pp.55-61
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    • 2022
  • Today's payment systems are becoming unmanned and changing to a way of paying with kiosks. This has the advantage of convenient payment because consumers can select a menu and specify the number of products to be purchased with just a touch of the screen. However, from the point of view of system security, the actual kiosk system has various vulnerabilities. This can hijack the administrator account, gain system privileges, and perform malicious actions. In addition, it is exposed to a number of security threats, such as the possibility of wasting unnecessary resources by abnormally increasing the number of payments, and causing the device to fail to operate normally. Therefore, in this paper, if any node of a participant in the solana blockchain approves an incorrect fork, the stake of the voting nodes is deleted. Also, since all participants can see the transaction history due to the nature of the block chain, I intend to write a thesis on a system that improves the vulnerability of kiosk payments by separating the access rights through the private blockchain.

Evaluation of brown rice to replace corn in weanling pig diet

  • Kim, Sheena;Cho, Jin Ho;Kim, Hyeun Bum;Song, Minho
    • Journal of Animal Science and Technology
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    • v.63 no.6
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    • pp.1344-1354
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    • 2021
  • This study was conducted to evaluate the effects of brown rice (Japonica) on growth performance, nutrient digestibility, and blood parameters of weanling pigs. A total of 60 weanling pigs (28-day-old, 30 barrows and 30 gilts, 6.73 ± 0.77 kg body weight [BW]) were randomly allotted to 2 dietary treatments (6 pigs per pen; 5 replicates per treatment) in a randomized complete block design with the initial BW and sex as blocks. The dietary treatments were a typical nursery diet based on corn and soybean meal (CON) and the CON replaced 50% of corn with brown rice (BR). Pigs were fed respective dietary treatments for 5 weeks. For the last week of experiment period, pigs were fed respective dietary treatments containing 0.2% chromic oxide as an indigestible marker. Fecal samples were collected from randomly selected 1 pig in each pen daily for the last 3 d after the 4-d adjustment period. Blood was collected from randomly selected 1 pig in each pen on d 0, 3, 7, and 14 after weaning. Compared with pig fed CON diet, pigs fed the BR diet were found to have higher (p < 0.05) final BW, overall average daily gain, and apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of dry matter and energy. However, there were no significant differences between the groups with respect to average daily feed intake, gain to feed ratio, frequency of diarrhea, and the AID and ATTD of crude protein during overall experimental period. Similarly, there were no significant differences on blood parameters between the groups. Thus, the findings of this study indicate that brown rice (Japonica) can be used to replace 50% of corn in the diet of pigs during the nursery period without negatively affecting growth performance, nutrient digestibility, or blood parameters.

Capacity Comparison of Two Uplink OFDMA Systems Considering Synchronization Error among Multiple Users and Nonlinear Distortion of Amplifiers (사용자간 동기오차와 증폭기의 비선형 왜곡을 동시에 고려한 두 상향링크 OFDMA 기법의 채널용량 비교 분석)

  • Lee, Jin-Hui;Kim, Bong-Seok;Choi, Kwonhue
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.5
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    • pp.258-270
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    • 2014
  • In this paper, we investigate channel capacity of two kinds of uplink OFDMA (Orthogonal Frequency Division Multiple Access) schemes, i.e. ZCZ (Zero Correlation Zone) code time-spread OFDMA and sparse SC-FDMA (Single Carrier Frequency Division Mmultiple Access) robust to access timing offset (TO) among multiple users. In order to reflect the practical condition, we consider not only access TO among multiple users but also peak to average power ratio (PAPR) which is one of hot issues of uplink OFDMA. In the case with access TO among multiple users, the amplified signal of users by power control might affect a severe interference to signals of other users. Meanwhile, amplified signal by considering distance between user and base station might be distorted due to the limit of amplifier and thus the performance might degrade. In order to achieve the maximum channel capacity, we investigate the combinations of transmit power so called ASF (adaptive scaling factor) by numerical simulations. We check that the channel capacity of the case with ASF increases compared to the case with considering only distance i.e. ASF=1. From the simulation results, In the case of high signal to noise ratio (SNR), ZCZ code time-spread OFDMA achieves higher channel capacity compared to sparse block SC-FDMA. On the other hand, in the case of low SNR, the sparse block SC-FDMA achieves better performance compared to ZCZ time-spread OFDMA.

In vitro evaluation of Rhus succedanea extracts for ruminants

  • Kim, Do Hyung;Lee, Shin Ja;Oh, Da Som;Lee, Il Dong;Eom, Jun Sik;Park, Ha Young;Choi, Seong Ho;Lee, Sung Sill
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.10
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    • pp.1635-1642
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    • 2018
  • Objective: This study was conducted to evaluate the effects of Rhus succedanea extract addition on in vitro ruminal fermentation and microbial growth. Methods: Two ruminally-fistulated steers consuming 600 g/kg timothy- and 400 g/kg cracked corn-based concentrate with free access to water and mineral block were used as rumen fluid donors. In vitro batch fermentation, with timothy as a substrate, was conducted for up to 72 h, with Rhus succedanea extracts added to achieve final concentrations of 0, 10, 30, 50, 70, and 90 mg/L. Results: Effective dry matter (DM) degradability rate linearly decreased (p = 0.046) depending on extract dosing levels. Total gas production after 24 to 72 h incubation tended to decrease following extract addition, beginning with 50 mg/L starting dose (significance of quadratic effects: p = 0.006, p<0.001, and p = 0.008 for 24, 48, and 72 h, respectively). Methane production decreased depending on dosing levels following 24 h (p<0.05) and 48 h (p<0.005) incubations and was the lowest with the 50 mg/L dose. The Rhus succedanea extracts increased the abundance of Fibrobacter succinogenes (p<0.05) and Ruminococcus flavefaciens (p = 0.0597) and decreased the abundance of methanogenic archaea (p<0.05) following 24 h incubation. Conclusion: Rhus succedanea was shown to reduce methane production and increase cellulolytic bacteria without any signs of toxic effects and with a minor effect on DM degradability.

A STUDY ON THE POSITION OF THE MANDIBULAR FORAMEN IN KOREAN CHILDREN USING PANORAMIC RADIOGRAPHS (파노라마 방사선 사진을 이용한 한국인 소아의 하악공 위치에 대한 연구)

  • Hong, So-Yi;Jeong, Seo-Young;Mah, Yon-Joo;Jung, Young-Jung;Ahn, Byung-Duk
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.4
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    • pp.368-375
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    • 2011
  • The aim of this study was to evaluate the position of the mandibular foramen in panoramic radiographs of Korean children to provide information for successful inferior alveolar nerve block anesthesia. 240 panoramic radiographs of 7 to 15-year-old boys and girls were analyzed. The subjects were divided into 4 groups in boys and girls according to their age.; 7-8, 9-10, 11-12 and 13-15 years old. The shortest distances from the center of the mandibular foramen to the anterior border of ramus, to the posterior border of ramus, to the antegonial notch and to the mandibular notch and the perpendicular distances from the center of the mandibular foramen to the occlusal plane were measured. The following results were obtained. 1) Although the relative position of the mandibular foramen in the ramus of mandible tended to move anteriorly for both genders with age, the vertical position did not correlate with age. 2) The mandibular foramen moved upward in relation to the occlusal plane with age, and showed statistically significant correlation with age(p<0.05). 3) The mandibular foramina of boys, when compared to those of girls, were located more superiorly in relation to the occlusal plane and more superiorly and posteriorly in the ramus of mandible.

THE SEALING ABILITY OF OBTURATION TECHNIQUES IN OPEN APEX (개방 근첨 치아의 근관 충전방법에 따른 치근단 폐쇄효과에 관한 연구)

  • So, Hyun;Choi, Ho-Young;Choi, Kyung-Kyu;Choi, Gi-Woon
    • Restorative Dentistry and Endodontics
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    • v.25 no.3
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    • pp.435-445
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    • 2000
  • The purpose of this study was to compare the leakage of four different obturation techniques in conjunction with immediate apical barrier of ${\beta}$-tricalcium phosphate(TCP) in teeth with open apex. Eighty single-rooted human premolar teeth were prepared and sectioned horizontally, so maximum diameter in apex was 4mm. Apical defects that were similar to open apex, were created with #1/2 round bur and SF104R bur. The apical foramen were opened to a size 80 file extended 3mm beyond the apex. The teeth were placed into the oasis block soaked saline to simulate periapical tissue often associated with pulpless teeth and received apical barriers consisting of TCP followed by obturation using lateral condensation technique, vertical condensation technique, continuous wave technique and thermoplasticized gutta-percha injection technique. Two unobturated teeth served as positive and negative controls. Teeth were immersed in resorcinol-formaldehyde resin for S days at $4^{\circ}C$, and the resin was allowed to polymerize completely for 4 days at room temperature. Teeth were then sectioned horizontally at 1.5mm(level 1), 2.5mm(level 2) and 3.5mm(level 3) from the apex, and examined under a stereomicroscope at ${\times}40$ magnification. The photographs were taken at ${\times}40$ magnification of the filling in each level and scanned. The leakage length in tooth/resin interface was measured at each of the three levels. Each ratio of leakage was obtained by calculating the ratio of the leakage length of canal wall infiltrated with resin to the total length of the canal and was analyzed statistically(One-way ANOVA and Scheffe test). The result were as follows : 1. At the level 1, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), but there was statistically significant(p<0.05). 2. At the level 2, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), and the most leakage in the continuous wave technique group(group 3). There was statistically significant difference between the thermoplasticized gutta-percha injection technique group and the continuous wave technique group(p<0.05). 3. At the level 3, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), but there were no statistically significant differences between other groups(p>0.05). These results suggest that thermoplasticized gutta-percha injection technique which had 1mm apical gutta-percha matrix after the formation of TCP apical barrier, can demonstrate favorable apical sealing.

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Effect of Slow-Release Fertilizer on Yield and Quality of Third-Harvest Tea Leaves (세물차의 수량 및 품질에 미치는 완효성비료 시비효과)

  • Park, Jang-Hyun;Choi, Hyeong-Kuk;Kim, Jong-Keun;Kim, Kil-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.38 no.5
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    • pp.269-273
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    • 2005
  • A field experiment was conducted to evaluate the effect of slow-release fertilizer on the yield and quality of the third-harvest tea leaves. The yield of the third harvested tea leaves was decreased to 5.8-14.4% in slow-release fertilizer block, except to the N $50kg\;10a^{-1}$ ($316kg\;10a^{-1}$), compared to traditional urea treatment ($313kg\;10a^{-1}$). Nitrogen uptake and nitrogen uptake efficiency of slow-release fertilizer was reduced as nitrogen application level increased. The contents of chemical components related to the tea quality such as total-nitrogen, total amino acid, chlorophyll and theanine were somewhat lower in the slow-release fertilizer treatments, except to the treatment of N $50kg\;10a^{-1}$, than those in the traditional urea application, but those of tannin, caffeine and vitamin C were not different among the treatments. In scoring test, apparence and quality of green tea of the slow-release fertility treatments were not different, except to the N $40kg\;10a^{-1}$ treatment, compared to those in the treatment of urea. In conclusion, slow-release fertilizer and conventional urea treatments showed not different in both yield and quality of green tea.

Image Processing of Pseudo-rate-distortion Function Based on MSSSIM and KL-Divergence, Using Multiple Video Processing Filters for Video Compression (MSSSIM 및 쿨백-라이블러 발산 기반 의사 율-왜곡 평가 함수와 복수개의 영상처리 필터를 이용한 동영상 전처리 방법)

  • Seok, Jinwuk;Cho, Seunghyun;Kim, Hui Yong;Choi, Jin Soo
    • Journal of Broadcast Engineering
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    • v.23 no.6
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    • pp.768-779
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    • 2018
  • In this paper, we propose a novel video quality function for video processing based on MSSSIM to select an appropriate video processing filter and to accommodate multiple processing filters to each pixel block in a picture frame by a mathematical selection law so as to maintain video quality and to reduce the bitrate of compressed video. In viewpoint of video compression, since the properties of video quality and bitrate is different for each picture of video frames and for each areas in the same frame, it is difficult for the video filter with single property to satisfy the object of increasing video quality and decreasing bitrate. Consequently, to maintain the subjective video quality in spite of decreasing bitrate, we propose the methodology about the MSSSIM as the measure of subjective video quality, the KL-Divergence as the measure of bitrate, and the combination method of those two measurements. Moreover, using the proposed combinatorial measurement, when we use the multiple image filters with mutually different properties as a pre-processing filter for video, we can verify that it is possible to compress video with maintaining the video quality under decreasing the bitrate, as possible.

The Poet Kim Shi-Jong living in both Joseon and Japan: the Meaning of 'Zainichi' Expressed in Epic Poem Niigata (조선과 일본에 사는 시인 김시종 - 장편시집 『니이가타』에 표현된 '재일'의 의미)

  • Kim, Gae-Ja
    • Cross-Cultural Studies
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    • v.45
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    • pp.7-32
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    • 2016
  • This article considers the meaning of 'Zainichi (在日)' expressed in epic poem Niigata (1970) written by Korean-Japanese poet Kim Shi Jong. Kim sets two points in his creation of poetry. One is summer of liberation released from Japanese colonial domination in 1945. The other is Japan where he lives as a Korean-Japanese. These two points have made him think about the meaning of living in post-colonial era and the national division of Korea, his home country. His thought like this is well expressed in his epic Niigata. Niigata was written in 1959 when the ship returning to North Korea departed from Niigata of Japan. However, Kim couldn't return to his home country at that time. He stowed away from South Korea to Japan in 1949. He participated in antigovernment activities occurred in Jeju Island to block the national division between the south and the north after the liberation in 1945, the so-called 4.3 incident. Besides, he was having conflict with the organization of North Korea at that time because it required a doctrinaire belief and creation in Korean. Kim was writing poems in Japanese and pursued the life of existence as a Korean-Japanese. Therefore, he decided to remain in Japan instead of returning to North Korea. Of course, he could not return to South Korea because he was a refugee. Kim imagined in Niigata, the place located in an extension of the 38th parallel and the spot of national division. He could not cross the division line when he was in his home country, but he could do it in Niigata through imagination. The life as a Korean-Japanese makes it possible. 'Zainichi', which means living in Japan, has been recognized as a worse situation compared to living in Korea. However, Kim changed his way of thinking. Zainichi can embrace South Korea, North Korea, and Japan. This is the very reason why he lives there as a Korean-Japanese. His thought like this is well expressed by symbolic representations and metamorphose as well as the imagination of spatial extension.

A computer vision-based approach for behavior recognition of gestating sows fed different fiber levels during high ambient temperature

  • Kasani, Payam Hosseinzadeh;Oh, Seung Min;Choi, Yo Han;Ha, Sang Hun;Jun, Hyungmin;Park, Kyu hyun;Ko, Han Seo;Kim, Jo Eun;Choi, Jung Woo;Cho, Eun Seok;Kim, Jin Soo
    • Journal of Animal Science and Technology
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    • v.63 no.2
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    • pp.367-379
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    • 2021
  • The objectives of this study were to evaluate convolutional neural network models and computer vision techniques for the classification of swine posture with high accuracy and to use the derived result in the investigation of the effect of dietary fiber level on the behavioral characteristics of the pregnant sow under low and high ambient temperatures during the last stage of gestation. A total of 27 crossbred sows (Yorkshire × Landrace; average body weight, 192.2 ± 4.8 kg) were assigned to three treatments in a randomized complete block design during the last stage of gestation (days 90 to 114). The sows in group 1 were fed a 3% fiber diet under neutral ambient temperature; the sows in group 2 were fed a diet with 3% fiber under high ambient temperature (HT); the sows in group 3 were fed a 6% fiber diet under HT. Eight popular deep learning-based feature extraction frameworks (DenseNet121, DenseNet201, InceptionResNetV2, InceptionV3, MobileNet, VGG16, VGG19, and Xception) used for automatic swine posture classification were selected and compared using the swine posture image dataset that was constructed under real swine farm conditions. The neural network models showed excellent performance on previously unseen data (ability to generalize). The DenseNet121 feature extractor achieved the best performance with 99.83% accuracy, and both DenseNet201 and MobileNet showed an accuracy of 99.77% for the classification of the image dataset. The behavior of sows classified by the DenseNet121 feature extractor showed that the HT in our study reduced (p < 0.05) the standing behavior of sows and also has a tendency to increase (p = 0.082) lying behavior. High dietary fiber treatment tended to increase (p = 0.064) lying and decrease (p < 0.05) the standing behavior of sows, but there was no change in sitting under HT conditions.