• Title/Summary/Keyword: property ($D_k$)

Search Result 1,619, Processing Time 0.03 seconds

A New Demosaicking Algorithm for Honeycomb CFA CCD by Utilizing Color Filter Characteristics (Honeycomb CFA 구조를 갖는 CCD 이미지센서의 필터특성을 고려한 디모자이킹 알고리즘의 개발 및 검증)

  • Seo, Joo-Hyun;Jeong, Yong-Jin
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.48 no.3
    • /
    • pp.62-70
    • /
    • 2011
  • Nowadays image sensor is an essential component in many multimedia devices, and it is covered by a color filter array to filter out specific color components at each pixel. We need a certain algorithm to combine those color components reconstructed a full color image from incomplete color samples output from an image sensor, which is called a demosaicking process. Most existing demosaicking algorithms are developed for ideal image sensors, but they do not work well for the practical cases because of dissimilar characteristics of each sensor. In this paper, we propose a new demosaicking algorithm in which the color filter characteristics are fully utilized to generate a good image. To demonstrate significance of our algorithm, we used a commerically available sensor, CBN385B, which is a sort of Honeycomb-style CFA(Color Filter Array) CCD image sensor. As a performance metric of the algorithm, PSNR(Peak Signal to Noise Ratio) and RGB distribution of the output image are used. We first implemented our algorithm in C-language for simulation on various input images. As a result, we could obtain much enhanced images whose PSNR was improved by 4~8 dB compared to the commonly idealized approaches, and we also could remove the inclined red property which was an unique characteristics of the image sensor(CBN385B).Then we implemented it in hardware to overcome its problem of computational complexity which made it operate slow in software. The hardware was verified on Spartan-3E FPGA(Field Programable Gate Array) to give almost the same performance as software, but in much faster execution time. The total logic gate count is 45K, and it handles 25 image frmaes per second.

A Demodulation Method for DS/CDMA Systems (DS/CDMA 시스템을 위한 새로운 복조 방식)

  • Jung, Bum-Jin;Jin, Ming-Lu;Kwak, Kyung-Sup
    • Journal of IKEEE
    • /
    • v.2 no.2 s.3
    • /
    • pp.212-224
    • /
    • 1998
  • There are two major factors of degrading the performance in the forward link of DS/CDMA systems. One is the multiple access interference (MAI) caused by using the same frequency bands simultaneously and the other is the multipath lading due to multipath propagation. PN codes which have minimum cross correlation properties among spread spectrum codes are necessary to reduce the MAI. In the conventional IS-95A system, the PN sequence has the period of $2^{15}$ and is of the length of 64 chips for spreading each data. In this case, since the length of PN code per bit is very short compared to the period of the PN code, the performance of the conventional system is not satisfied in view of suppressing the multipath interference. However, the correlation property of the PN codes at the demodulation can be improved by increasing the interval of Integration at the demodulation. This paper proposes a demodulation method to reduce the cross correlation among PN codes. The performance of the proposed demodulation method is investigated through computer simulations. We used multipath Ray lading channel and AWGN channel in the simulation. Our simulation results show the improved performance of $0.25{\sim}0.5dB$ SNR in a given BER compared to the conventional demodulation scheme.

  • PDF

Analysis of the Relationship between Cognitive Levels and Achievement of Science Process Skills by Practical Assessment (실험 평가를 통한 탐구과정 기능의 성취도와 인지 수준과의 관계 분석)

  • Min, Hye-Young;Paik, Seoung-Hey;Kang, Dae-Hun
    • Journal of The Korean Association For Science Education
    • /
    • v.19 no.2
    • /
    • pp.256-265
    • /
    • 1999
  • The purpose of this study is to investigate the relationship between cognitive levels and achievement of science process skills. A science laboratory process skills test based on optional instrument of the SISS was administered to a sample of 162 students in the 8th grade. Practical assessment tasks consisted of the contents about acid, base, density, and a property of cobalt chloride. The format of this practical test was the station type that students had to conduct a short activity. Science process skills included three sub-skills which were categorized as designing, performing, and reasoning. As cognitive levels develop from concrete operational stage to transition stage and formal operational stage. total scores of science process skills and mean scores of sub-skills were significantly increased. Regardless of cognitive levels. all students were more successful on performing than designing or reasoning. In case of being controlled cognitive levels, gender differences and area differences were not detected in achievement of science process skills. According to these results. there was a strong relationship between cognitive levels and achievement of science process skills by practical assessment. This study implies that considering student's cognitive levels is very important for improving science process skills.

  • PDF

Activation Factors of Industry Cooperation through Comparison Study on Domestic and International Industry Cooperation Programs (국내외 산학협력프로그램 비교를 통한 산학협력 활성화 방안 연구)

  • Kim, Hye Sun;Kim, Jong Boo;Kim, Hyoung Ro
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.9 no.2
    • /
    • pp.187-200
    • /
    • 2014
  • Industry Cooperation is not the choice of national development but the inevitable component in the world. Industry cooperation results of the reconstruction of the country is an important place as an essential element of the economic development of the national policy in the major economies. Despite several changes in the international economic environment, United States, Canada, Finland, Sweden, Israel settled and maintaining the sustainable development of the countries which successfully established Industry-University Cooperation or Industry-Acaemy Cooperation system in history. In this study, delivered to the realistic ways of Industry cooperation through comparison study on domestic and international cooperation programs. The new activation programs of industry academic cooperation are delivered, that is, The bonus payments system of technology development patent and free technology transfer for joint development, bonus points system and evaluation indicators for joint capacity building program which participate student, industry and academic sector, step-by-step training. system for total employment and entrepreneurship at the same time strengthening management training programs and education opportunity gives to the benefits for the community members. Finally, Intellectual property expert matching program which develops basis of technology trader and expert maps in the smallest unit by administrative area. practice the internet information search services in national wide network for this matching program and government office dedicated to staffing for technology transfer.

  • PDF

A Study on the Thermal Characterization of Barley ${\beta}-Glucan$ [mixed-linked $(1-3),(1-4)-{\beta}-D-Glucan$] by Differential Scanning Calorimetry (DSC에 의한 보리 ${\beta}-Glucan$ [mixed-linked$(1-3),(1-4)-{\beta}-D-Glucan$의 열적 특성에 관한 연구)

  • Cha, Hee-Sook;Kim, Mi-Ok;Koo, Sung-Ja
    • Korean Journal of Food Science and Technology
    • /
    • v.25 no.1
    • /
    • pp.22-27
    • /
    • 1993
  • Crude ${\beta}-glucan$ extracted from Barley was purified by stepwide enzyme treatment with thermostable ${\alpha}-amylase$, amyloglucosidase and protease. The thermal properties of Barley ${\beta}-glucan$ were investigated by Differential Scanning Calorimetry. Three endotherms have been observed on DSC thermograms of Barley ${\beta}-glucan$. The first endotherm which produced the gelatinization phenomena commonly observed in Barley ${\beta}-glucan$ became the focus of this study. The temperature range and the enthalpy of gelation exhibited maximum values with increasing concentration of Barley ${\beta}-glucan$. Gelating Barley ${\beta}-glucan$ registered an enthalpy of approximately 0.23 cal/g and exhibited onset temperature (To), peak temperature (Tp) and conclusion temperature (Tc) of $48.8^{\circ}C,\;61.2^{\circ}C\;and\;78.5^{\circ}C$ respectively. The temperature and enthalpy of gelatinizing Barley ${\beta}-glucan$ at both alkali and acid conditions were lower than those at pH 7. With salt present, the Tp and Tc of gelating Barley ${\beta}-glucan$ produced lower temperatures than in conditions where salt was absent, and the enthalpy abruptly decreased. However, increasing salt concentrations did not affect the gelation temperature and the enthalpy of Barley ${\beta}-glucan$. The 'true melting' temperature of Barley ${\beta}-glucan$ was near $184^{\circ}C$ and the melting enthalpy was approximately 34.6 cal/g. The Barley ${\beta}-glucan$ decomposition temperature was in the range of $316^{\circ}C{\sim}346^{\circ}C$.

  • PDF

Effects of Preservative Containing Chitosan on the Shelf Life of Pork Patty (Chitosan이 함유된 보존제의 첨가가 돈육 Patty의 저장에 미치는 효과)

  • Park, La-Young;Jeong, Eun-Ju;Lee, Shin-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.42 no.9
    • /
    • pp.1446-1451
    • /
    • 2013
  • The quality characteristics of pork patty prepared with chitosan containing preservatives during storage at $4^{\circ}C$ were investigated to improve its functional property and shelf life using food preservatives of natural origin (PI; 0.1% chitosan, 2.5% citric acid, 100 ppm grapefruit seed extract, 0.2% adipic acid, 0.1% Cinnamomum extract, D.W. 97.09% and PII; 0.1% chitosan, 2.5% citric acid, 100 ppm grapefruit seed extract, 0.2% adipic acid, 0.1% Lysimachia christinae Hance extract, D.W. 97.09%). The sensory qualities (taste, appearance, texture and overall acceptability) of patties preserved with PI (1, 3 and 5%) and PII (1, 3 and 5%) were also investigated. The taste and overall acceptability of patties prepared with 1% PI and 1% PII were higher than those of the control. The DPPH radical scavenging activities of the control, 1% PI and 1% PII treated patties were 13.54%, 21.78% and 14.07%, respectively. The total aerobes and coliform count of patties preserved with 1% PI were $10^4$ CFU/g and $10^2$ CFU/g, respectively, after 10 days storage at $4^{\circ}C$. Cooking loss from 1% PI and 1% PII treated patties was lower than that of from the control. Water holding capacity was the highest for 1% PI (65.84%), followed by 1% PII and then the control. The shelf life of patties prepared with 1% PI and 1% PII was extended by about 5 days relative to the control at $4^{\circ}C$.

A Study on EM Wave Absorber for Electromagnetic Wave Environment of Wireless LAN at 5.2 GHz (5.2 GHz 무선 LAN의 전자파 환경 대책용 전파흡수체에 관한 연구)

  • Yoo, Gun-Suk;Choi, Dong-Soo;Kim, Dong-Il
    • Journal of Navigation and Port Research
    • /
    • v.34 no.1
    • /
    • pp.15-19
    • /
    • 2010
  • Recently, the wireless LAN system is rapidly growing because of its convenience of high speed communication. However, the wireless LAN systems at indoor places occur multi-propagation path by reflected waves from walls, ceilings, floors, and desks. Multipath problems cause transmission errors and degradation of communication speed. These problems can be solved by using EM wave absorbers. In this paper, we analyzed property of Graphite and derived the optimum ratio of Graphite: CPE to develop EM wave absorber for the wireless LAN system. First, we fabricated several samples in different composition ratios of Graphite and CPE, and then measured the reflection coefficient of each samples. Material constants of permittivity and permeability were calculated using the measured data and designed EM wave absorber. Secondly, the EM wave absorber was fabricated and tested on the base of the simulation data. As a result, it showed that the EM wave absorber in 1.7 mm thickness with the ratio of Graphite: CPE=50:50 wt.% has excellent absorption ability more than 27 dB at 5.2 GHz.

Study on the Dissolution of Sandstones in Gyeongsang Basin and the Calculation of Their Dissolution Coefficients under CO2 Injection Condition (이산화탄소 지중 주입에 의한 경상분지 사암의 용해반응 규명 및 용해 반응상수값 계산)

  • Kang, Hyunmin;Baek, Kyoungbae;Wang, Sookyun;Park, Jinyoung;Lee, Minhee
    • Economic and Environmental Geology
    • /
    • v.45 no.6
    • /
    • pp.661-672
    • /
    • 2012
  • Lab scale experiments to investigate the dissolution reaction among supercritical $CO_2$-sandstone-groundwater by using sandstones from Gyeongsang basin were performed. High pressurized cell system (100 bar and $50^{\circ}C$) was designed to create supercritical $CO_2$ in the cell, simulating the sub-surface $CO_2$ storage site. The first-order dissolution coefficient ($k_d$) of the sandstone was calculated by measuring the change of the weight of thin section or the concentration of ions dissolved in groundwater at the reaction time intervals. For 30 days of the supercritical $CO_2$-sandstone-groundwater reaction, physical properties of sandstone cores in Gyeongsang basin were measured to investigate the effect of supercritical $CO_2$ on the sandstone. The weight change of sandstone cores was also measured to calculate the dissolution coefficient and the dissolution time of 1 g per unit area (1 $cm^2$) of each sandstone was quantitatively predicted. For the experiment using thin sections, mass of $Ca^{2+}$ and $Na^+$ dissolved in groundwater increased, suggesting that plagioclase and calcite of the sandstone would be significantly dissolved when it contacts with supercritical $CO_2$ and groundwater at $CO_2$ sequestration sites. 0.66% of the original thin sec-tion mass for the sandstone were dissolved after 30 days reaction. The average porosity for C sandstones was 8.183% and it increased to 8.789% after 30 days of the reaction. The average dry density, seismic velocity, and 1-D compression strength of sandstones decreased and these results were dependent on the porosity increase by the dissolution during the reaction. By using the first-order dissolution coefficient, the average time to dissolve 1 g of B and C sandstones per unit area (1 $cm^2$) was calculated as 1,532 years and 329 years, respectively. From results, it was investigated that the physical property change of sandstones at Gyeongsang basin would rapidly occur when the supercritical $CO_2$ was injected into $CO_2$ sequestration sites.

Neuroprotection of Recombinant Human Erythropoietin Via Modulation of N-methyl-D-aspartate Receptors in Neonatal Rats with Hypoxic-ischemic Brain Injury (신생 백서의 저산소성 허혈성 뇌손상에서 NMDA receptor 조절을 통한 유전자 재조합 인 에리스로포이에틴의 신경보호)

  • Jang, Yoon-Jung;Seo, Eok-Su;Kim, Woo-Taek
    • Neonatal Medicine
    • /
    • v.16 no.2
    • /
    • pp.221-233
    • /
    • 2009
  • Purpose: Erythropoietin (EPO) has neuroprotective effects in many animal models of brain injury, including hypoxic-ischemic (HI) encephalopathy, trauma, and excitotoxicity. Current studies have demonstrated the neuroprotective effects of EPO, but limited data are available for the neonatal periods. Here in we investigated whether recombinant human EPO (rHuEPO) can protect the developing rat brain from HI injury via modulation of NMDA receptors. Methods: In an in vitro model, embryonic cortical neuronal cell cultures from Sprague-Dawley (SD) rats at 19-days gestation were established. The cultured cells were divided into five groups: normoxia (N), hypoxia (H), and 1, 10, and 100 IU/mL rHuEPO-treated (H+E1, H+ E10, and H+E100) groups. To estimate cell viability and growth, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was done. In an in vivo model, left carotid artery ligation was performed on 7-day-old SD rat pups. The animals were divided into six groups; normoxia control (NC), normoxia Sham-operated (NS), hypoxia-ischemia only (H), hypoxia-ischemia+vehicle (HV), hypoxia-ischemia+rHuEPO before a HI injury (HE-B), and hypoxia-ischemia+rHuEPO after a HI injury (HE-A). The morphologic changes following brain injuries were noted using hematoxylin and eosin (H/E) staining. Real-time PCR using primers of subunits of NMDA receptors (NR1, NR2A, NR2B, NR2C and NR2D) mRNA were performed. Results: Cell viability in the H group was decreased to less than 60% of that in the N group. In the H+E1 and H+E10 groups, cell viability was increased to >80% of the N group, but cell viability in the H+E100 group did not recover. The percentage of the left hemisphere area compared the to the right hemisphere area were 98.9% in the NC group, 99.1% in the NS group, 57.1% in the H group, 57.0% in the HV group, 87.6% in the HE-B group, and 91.6% in the HE-A group. Real-time PCR analysis of the expressions of subunits of NMDA receptors mRNAs in the in vitro and in vivo neonatal HI brain injuries generally revealed that the expression in the H group was decreased compared to the N group and the expressions in the rHuEPO-treated groups was increased compared to the H group. Conclusion: rHuEPO has neuroprotective property in perinatal HI brain injury via modulation of N-methyl-D-aspartate receptors.

Physiochemical Properties and Plant Growth of The Hydroponic Substrate Using Waste Wood Chip (양액재배용 목재고형배지의 이화학적 특성과 작물생육 특성)

  • Kwon, Gu-Joong;Yang, Ji-Wook;Park, Hyo-Sub;Cho, Joon-Hyeong;Kim, Dae-Young
    • Journal of the Korean Wood Science and Technology
    • /
    • v.43 no.3
    • /
    • pp.400-409
    • /
    • 2015
  • This study examined the plant growth and development characteristics of leafy vegetables on the hydroponic substrates of waste wood chips, radiate pine chips, and mat type of waste wood chips. The bulk density of waste wood chips and radiata pine chips were $0.2g/cm^3$ and $0.16g/cm^3$, respectively. The moisture retention properties of both the radiata pine chips and waste wood chips were found to be similar but not better than those of the control rock wool and coco peat hydroponic substrates. The moisture retention property of the mat type was found to be the lowest. The chemical analysis of waste wood hydroponic substrates (w/v) was as follows.; The pH was 6.59, electric conductivity was 6.76 dS/m, total nitrogen content was 0.5%, C/N ratio was 113%, phosphorus was 10.1 ppm, potassium was 77 ppm, calcium was 531 ppm, magnesium was 49 ppm, and sodium was 96 ppm. The results from the radiata pine chemical analysis showed that it had a pH of 5.29, electric conductivity of 4.49 dS/m, total nitrogen content of 0.32%, C/N ratio of 180%, phosphorus of 6.4 ppm, potassium of 83 ppm, calcium of 97 ppm, magnesium of 29 ppm, and sodium of 59 ppm. Except for the plants grown in mat type, the developmental characteristics of the plants grown in rock wool and coco peat hydroponic substrates were similar. Based on the results of the experiment, waste wood resources may possibly be used as an organic solid medium in place of the existing rock wool and coco peat medium.