• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.11 no.5
• /
• pp.85-96
• /
• 2001

This paper describes saturation attacks on reduced-round versions of SKIPJACK. To begin with, we will show how to construct a 16-round distinguisher which distinguishes 16 rounds of SKIPJACK from a random permutation. The distinguisher is used to attack on 18(5~22) and 23(5~27) rounds of SKIPJACK. We can also construct a 20-around distinguisher based on the 16-round distinguisher. This distinguisher is used to attack on 22(1~22) and 27(1~27) rounds of SKIPJACK. The 80-bit user key of 27 rounds of SKIPJACK can be recovered with $2^{50}$ chosen plaintexts and 3\cdot 2^{75}$ encryption times.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.16 no.5
• /
• pp.109-120
• /
• 2017

It is important to estimate objectively in the driving test. Especially, the driving test is examined by totally driving ability, rule observation and situational judgement. For this, a grading automation system for driving test was presented by using GPS, sensor data and equipment operation informations. This system is composed of vehicle mounted module, automatic grading terminal, data controller, data storage and processing server. The vehicle mounted module gathters sensor data in the car. The terminal performs automatic grading using the received sensor data according the driving test criterion. To overcome the misposition of vehicle in the map due to GPS error, we proposed the automatic grading system by map matching method, path deviation and return algorithm. In the experimental results, it was possible to grade automatically, display the right position of the car, and return to the right path under 10 seconds when the vehicle was out of the shadow region of the GPS. This system can be also applied to the driving education.

• Korean Journal of Microbiology
• /
• v.35 no.1
• /
• pp.72-77
• /
• 1999

To investigate soil bacterial diversity according to vegelalioo types, utilizing ability of sole carbon sources and restriction enzyme patterns of 16s rDNA were analyzed. From the both results; five kinds of soil microbial communities were grouped as forest soil (Quercus mongolica and Pinus densi&ra vegetation), grass-agricultured soil and microbial communities of naked soil. But, both soil microbial communities of directily exlracted from ths soil and indirectly extracted from heterotrophic bacteria that cultured soil in LB medium showed very different similarity.

• Journal of ILASS-Korea
• /
• v.29 no.1
• /
• pp.16-22
• /
• 2024

The EU (European Union) was introduced Euro-6e in 2023. Recently, the EU prepare to introduce Euro-7. One of difference Euro-6e and Euro-7 is test route condition. This study developed 5 test routes that have different characteristics and severity. The severity of test routes was made by traffic and road gradient. And this study was conducted RDE test on 5 test routes for Light-Duty diesel vehicle (Euro-6d). Based on the test results, the emission characteristics of CO₂ and NOx were analyzed according to the severity of the test routes. Especially, 4 test routes were satisfied normal driving condition of Euro-7 and other test route was satisfied extended driving condition of Euro-7.

• Journal of IKEEE
• /
• v.17 no.3
• /
• pp.385-392
• /
• 2013

In this paper, microstrip antenna to enhance the isolation between transmitting port and receiving port under the proximity objects is proposed, and applied to the Doppler radar sensor working at 5.8GHz ISM band which detects vital signals of a human body. Two 3dB quadrature hybrids are placed around radiation patch to form a balanced structure between transmitting port and receiving port, such that it consistently provides enhanced Tx/Rx isolation and excellent return loss over nearby objects. It is theoretically analyzed and simulated to verify the validity of the proposed application. The fabricated antenna that is 2mm away from the human body, has more than 16 dB return loss and at least 30dB isolation over ISM frequency band of 5.8GHz.

• Membrane Journal
• /
• v.25 no.5
• /
• pp.398-405
• /
• 2015

Facilitated transport is considered to be a possible solution to simultaneously improve permeability and selectivity, which is challenging in normal polymeric membranes based on solution-diffusion transport only. We investigated the effect of adding mesoporous $TiO_2$ ($m-TiO_2$) upon the separation performance of facilitated olefin transport membranes comprising poly(vinyl pyrrolidone), Ag nanoparticles, and 7,7,8,8-tetracyanoquinodimethane as the polymer matrix, olefin carrier, and electron acceptor, respectively. In particular, $m-TiO_2$ was prepared by means of a facile, mass-producible method using poly(vinyl chloride)-g-poly(oxyethylene methacrylate) graft copolymer as the template. The crystal phase of $m-TiO_2$ consisted of an anatase/rutile mixture, of crystallite size approximately 16 nm as determined by X-ray diffraction. The introduction of $m-TiO_2$ increased the membrane diffusivity, thereby increasing the mixed-gas permeance from 1.6 to 16.0 GPU ($1GPU=10^{-6}cm^3$(STP)/($s{\times}cm^2{\times}cmHg$), and slightly decreased the propylene/propane selectivity from 45 to 37. However, both the mixed-gas permeance and selectivity of the membrane containing $m-TiO_2$ rapidly decreased over time, whereas the membrane without $m-TiO_2$ had more stable long-term performance. This difference might be attributed to specific chemical interactions between $TiO_2$ and Ag nanoparticles, causing Ag to lose activity as an olefin carrier.

• The Journal of the Korea Contents Association
• /
• v.13 no.10
• /
• pp.403-411
• /
• 2013

The purpose of this study was to investigate on paid hospital-nurses' work perception, knowledge, performance and the performance-related factors of a nurse who works in a hospital with no guardian which is phased in its beginning as well as interactions between the factors. Data were collected from nurses working in wards without guardian at 9 hospitals among a total of 10 Korean hospitals carrying out a national pilot project which is designed for institutionalization of national caregiving services. Self reported questionnaires were used to collect data from 167 nurses, and 135 returned forms were analyzed(December, 2010). The score of perception was 4.24/5.00, knowledge 4.25/5.00, and performance 3.49/5.00. The performance was significantly different depending on the hospital types(p=.002). Significant correlations were found among perception(p<.001), knowledge(p=.004) and performance. The degree of perception(p<.001) and types of hospital(p<.001) attributed to 16.5% of variance in the practice. To enhance level of performance by taking account of perception and types of hospital, can be effective for hospital-nurses when there is no guardian.

• The Korean Journal of Food And Nutrition
• /
• v.33 no.6
• /
• pp.631-638
• /
• 2020

This study was conducted to investigate the temperatures inside and outside the pot as well as the quality characteristics of traditional Doenjang made by seven different farmers, in the Gyeonggi province during fermentation. The outside temperature of each region in the province was 5 to 10℃ higher in one place, in which fermentation took place inside the glass greenhouse, compared to other regions, while six other places showed similar changes in temperature. The moisture contents of the samples decreased according to the progress of the fermentation period from 53.6~62.3% to 51.0~58.5%. The salinity generally increased from 9.7~14.2% to 10.6~16.3% except for samples B and D, which declined from 17.0~17.2% to 16.6~16.9%. The amino-type nitrogen contents increased from 180.3~557.8 mg% to 437.3~840.7 mg%. The ammonia-type nitrogen contents decreased from 116.3~561.9 mg% to 70.7~149.2 mg%. Overall, the color of Doenjang was similar, but sample E had higher a and b values than the other regions, and the total bacterial count in the entire region was similar.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.3
• /
• pp.905-914
• /
• 2019

In this study, The PMF model was used to identify pollutant sources and their contribution to pollution sources of $PM_{2.5}$. The contribution of A city to each source was 19.8% for Secondary Sulfate, followed by Mobile 19.5%, Industry 16.0%, Biomass Buring 14.1%, Secondary Nitrate 14.1%, Oil Combustion 11.6%, Aged Sea Salt 2.6%, Soil 2.5% and so on. Sulfate and Ammonium concentrations were the highest contributing sources in the source profile, which was analyzed to be Secondary Aerosols produced by Photochemical Reactions of gaseous precursors (SOx and ammonia gas) in the atmosphere.

• JOURNAL OF ELECTRICAL WORLD
• /
• no.5 s.25
• /
• pp.11-16
• /
• 1972

업무를 수행 할때에는 조명의 효과각 극히 중요시 되어야 함에도 불구하고 이것이 거의 무시되고 있다. 특정한 업무에 따라 적절한 조명속에서 일하는 것은 일의 능율을 올리고 피로 격감시키는 것이다. 이러한 점은 고용주나 고용인 모두에게 이익을 주는 것이다.