• Title/Summary/Keyword: Step-Frequency

Search Result 1,432, Processing Time 0.026 seconds

Kinetic Studies of Pyrolysis and Char-$CO_2$ Gasification on Low Rank Coals (저급탄의 열분해 및 촤-$CO_2$ 가스화 반응의 속도론적 연구)

  • Kang, Suk-Hwan;Ryu, Jae-Hong;Park, Soo-Nam;Byun, Yong-Soo;Seo, Seok-Jung;Yun, Yong-Seung;Lee, Jin-Wook;Kim, Yong-Jeon;Kim, Joo-Hoe;Park, Sam-Ryong
    • Korean Chemical Engineering Research
    • /
    • v.49 no.1
    • /
    • pp.114-119
    • /
    • 2011
  • Thermogravimetric analysis(TGA) was carried out for pyrolysis and char-$CO_2$ gasification of low rank Indonesian ABK coal and China lignite. The pyrolysis rate was successfully described by a two-step model adopting the modified Kissinger method. The shrinking core model, when applied to char-$CO_2$ gasification gave initial activation energy of 189.1 kJ/mol and 260.5 kJ/mol for the ABK coal and China lignite, respectively. Thus, the char-$CO_2$ gasification has been successfully simulated by the shrinking core model. In particular, the activation energy of char-$CO_2$ gasification calculated in this work is similar to the results on the anthracite coal, but considerable difference exists when other models or coal types are used.

Spectral and Energy Efficient Spatially Modulated Non-Orthogonal Multiple Access (NOMA) For 5G (5G를 위한 주파수 및 에너지 효율적인 공간 변조 비-직교 다중 접속 기법)

  • Irfan, Mohammad;Kim, Jin Woo;Shin, Soo Young
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.40 no.8
    • /
    • pp.1507-1514
    • /
    • 2015
  • Non-orthogonal multiple access (NOMA) is a promising candidate for 5G networks. NOMA achieves superior spectral efficiency than conventional orthogonal multiple access (OMA), as in NOMA multiple users uses the same time and frequency resources. Multiple-input-multiple-output (MIMO) is one another promising technique that can enhance system performance. In this paper we present a spectral and energy efficient multiple antenna based NOMA scheme, known as spatially modulated NOMA. In the proposed scheme the cell edge users are multiplexed in spatial domain, which means the information to cell edge users is conveyed using the transmit antenna indices. In NOMA the performance of cell edge users are deeply effected as it treats signals of others as noise. The proposed scheme achieves superior spectral efficiency than the conventional NOMA. The number of decoding steps involved in decoding NOMA signal reduces by one as cell edge user is multiplexed in spatial domain. The proposed scheme is more energy efficient as compare to conventional NOMA. All of the three gains high spectral, energy efficiency and one step reduction in decoding comes at cost of multiple transmit antennas at base station.

Analysis of SNPs in Bovine CSRP3, APOBEC2 and Caveolin Gene Family (소의 CSRP3, APOBEC2, Caveolin 유전자들의 단일염기다형 분석)

  • Bhuiyan, M.S.A.;Yu, S.L.;Kim, K.S.;Yoon, D.;Park, E.W.;Jeon, J.T.;Lee, J.H.
    • Journal of Animal Science and Technology
    • /
    • v.49 no.6
    • /
    • pp.719-728
    • /
    • 2007
  • The cysteine and glycine rich protein 3 (CSRP3), apolipoprotein B mRNA editing enzyme catalytic polypeptide‐like 2(APOBEC2) and caveolin (CAV) gene family(CAV1, CAV2, CAV3) have been reported to play important roles for carcass and meat quality traits in pig, mouse, human and cattle. As an initial step, we investigated SNPs in these 5 genes among eight different cattle breeds. Eighteen primer pairs were designed from bovine sequence data of NCBI database to amplify the partial gene fragments. Sequencing results revealed 9 SNPs in the coding regions of three caveolin genes, 1 SNP in CSRP3 and 3 SNPs in APOBEC2 gene. All the identified SNPs were confirmed by PCR-RFLP. Also, 9 more intronic SNPs were detected in these genes. However, all identified mutations in the coding region do not change amino acid sequence. Allelic distributions were significantly different for 5 SNPs in CAV2, CAV3, CSRP3 and APOBEC2 genes among the eight different breeds. These results gave some clues about the polymorphisms of these genes among the cattle breeds and will be useful for further searches for identifying association between these SNPs and meat quality traits in cattle.

A Study on the Energy-saving Variation by the Reduction of Insulation Boundary in Mixed-use Building (주상복합건물에서 단열 경계구역 축소에 따른 에너지 절감량 변화에 관한 연구)

  • Kim, Dae-Won;Kim, Young-Il;Kim, Sung-Min;Cho, Jin-Hwan;Chung, Kwang-Seop
    • Journal of Energy Engineering
    • /
    • v.21 no.2
    • /
    • pp.152-157
    • /
    • 2012
  • Due to the global warming and energy exhaustion, energy efficiency improvement of construction is recognized the stream of times. To improve the efficiency of the building, in order to energy saving, passive elements should be applied. Then the first step be supposed that applying the new standards about the insulation boundary. The current insulation boundary standards are not reasonable as well as does not divide the purposes. As a result, energy is being wasted and many civil complaints are also occurred. To improve these problems, applying the insulation boundary need to divide the heating and non-heating and subdivide the purpose of construction. In this study, accurate real heating and air conditioning areas are presented that work on the new insulation boundary of purposes and applicable standards. This proposed, by the real heating and air conditioning areas, insulation boundary of purposes, matching the reasonable capacity and load of equipment, by working on standards by optimal maintenance can be energy saving, to present guidelines that environment improvement of actual residents as well as energy saving be expected.

Representative Labels Selection Technique for Document Cluster using WordNet (문서 클러스터를 위한 워드넷기반의 대표 레이블 선정 방법)

  • Kim, Tae-Hoon;Sohn, Mye
    • Journal of Internet Computing and Services
    • /
    • v.18 no.2
    • /
    • pp.61-73
    • /
    • 2017
  • In this paper, we propose a Documents Cluster Labeling method using information content of words in clusters to understand what the clusters imply. To do so, we calculate the weight and frequency of the words. These two measures are used to determine the weight among the words in the cluster. As a nest step, we identify the candidate labels using the WordNet. At this time, the candidate labels are matched to least common hypernym of the words in the cluster. Finally, the representative labels are determined with respect to information content of the words and the weight of the words. To prove the superiority of our method, we perform the heuristic experiment using two kinds of measures, named the suitability of the candidate label ($Suitability_{cl}$) and the appropriacy of representative label ($Appropriacy_{rl}$). In applying the method proposed in this research, in case of suitability of the candidate label, it decreases slightly compared with existing methods, but the computational cost is about 20% of the conventional methods. And we confirmed that appropriacy of the representative label is better results than the existing methods. As a result, it is expected to help data analysts to interpret the document cluster easier.

A Survey on the Meal Management Attitudes of Housewives Who Had Elementary Schoolchildren in a Remote Rural Country in Korea (일부 벽지 농촌 가정 주부의 식생활 관리 실태 조사)

  • Kim, Jin-Yang;Kim, Sun-Hyo
    • Journal of the Korean Society of Food Culture
    • /
    • v.20 no.2
    • /
    • pp.131-143
    • /
    • 2005
  • This study is performed to examine the meal management attitudes of housewives who had elementary schoolchildren in the remote rural areas(RA: n = 318, $37.2{\pm}0.3$ years of age) in comparison to those in their vicinity urban area(UA: n = 349, $36.9{\pm}0.2$ years of age) in the Chungnam province in Korea. The subjects were asked to fill out the questionnaire on their attitudes of meal management for their families. The results obtained in this study were as followings: (1) Most husbands of the subjects had a farming job in the RA while they had salaried workers in the UA(p<0.001). Education levels of both subjects and their husbands were lower in the RA than in the UA. Nuclear families were dominated by both groups, however single parent-family and step parent-family were more prevalent in the RA than in the UA. (2) in terms of ways of getting foods such as grains, meats, eggs, vegetables and fruits, the RA housewives relied more often on self-production than did the UA housewives(p<0.001). (3) The frequency of purchasing unprocessed foods was lower in the RA than in the UA(p<0.001). The RA housewives purchased the convenient foods such as instant noodles(p<0.05), ready to eatsoups(p<0.001), retort pouch foods(p<0.05) and instant teas(p<0.05) more frequently than did the UA housewives, while tuna, canned in oil(p<0.01), milk and their products(p<0.001), soybean products(p<0.001) and snacks(p<0.01) were purchased less often by the RA housewives. (4) Family members except housewives engaged more often in meal preparation in the RA than did those in the UA(p<0.001), which was more strongly observed for dinner. The time spent in preparing the dinner was shorter in the RA than in the UA(p<0.001). (5) The degrees of endeavor to provide the subjects' offspring with balanced meal(p<0.001) and nutrition education(p<0.01) were lower in the RA than in the UA. The RA housewives had more difficulty for performing meal management because of 'over work-related fatigue', 'insufficient money to purchase foods' and 'far distance from grocery' than the UA housewives(p<0.001). The RA housewives had lower score on nutritional knowledge(p<0.001) and wanted more strongly nutritional knowledge to improve the quality of family's meal than did the UA housewives(p<0.01). Therefore, the RA housewives had various problems regarding meal management such as 'over work related to fatigue', 'food-purchasing inconvenience', 'low economic status of family' and 'lack of nutritional knowledge'. As a consequence the RA housewives relied on cheap convenient foods more often in order to prepare the meal easily than did the UA housewives. These findings emphasize the need in the RA for nutrition education for housewives and a range of nutrition policies that focus upon the social and economic determinants of food choice within families to improve the nutritional status of the RA residents.

Development of Image-map Generation and Visualization System Based on UAV for Real-time Disaster Monitoring (실시간 재난 모니터링을 위한 무인항공기 기반 지도생성 및 가시화 시스템 구축)

  • Cheon, Jangwoo;Choi, Kyoungah;Lee, Impyeong
    • Korean Journal of Remote Sensing
    • /
    • v.34 no.2_2
    • /
    • pp.407-418
    • /
    • 2018
  • The frequency and risk of disasters are increasing due to environmental and social factors. In order to respond effectively to disasters that occur unexpectedly, it is very important to quickly obtain up-to-date information about target area. It is possible to intuitively judge the situation about the area through the image-map generated at high speed, so that it can cope with disaster quickly and effectively. In this study, we propose an image-map generation and visualization system from UAV images for real-time disaster monitoring. The proposed system consists of aerial segment and ground segment. In the aerial segment, the UAV system acquires the sensory data from digital camera and GPS/IMU sensor. Communication module transmits it to the ground server in real time. In the ground segment, the transmitted sensor data are processed to generate image-maps and the image-maps are visualized on the geo-portal. We conducted experiment to check the accuracy of the image-map using the system. Check points were obtained through ground survey in the data acquisition area. When calculating the difference between adjacent image maps, the relative accuracy was 1.58 m. We confirmed the absolute accuracy of the image map for the position measured from the individual image map. It is confirmed that the map is matched to the existing map with an absolute accuracy of 0.75 m. We confirmed the processing time of each step until the visualization of the image-map. When the image-map was generated with GSD 10 cm, it took 1.67 seconds to visualize. It is expected that the proposed system can be applied to real - time monitoring for disaster response.

A Study on the Transport-related Impacts of Flexible Working Policy using Activity-Based Model (활동기반모형을 이용한 유연근무제의 교통부문 영향 연구)

  • CHO, Sung-Jin;BELLEMANS, Tom;JOH, Chang-Hyeon;CHOI, Keechoo
    • Journal of Korean Society of Transportation
    • /
    • v.35 no.6
    • /
    • pp.511-524
    • /
    • 2017
  • This study aims to evaluate the availability of ABM (Active-Based Model), FEATHERS, as a policy evaluation tool. To achieve the goal, scenario analysis on flexible working policy was conducted to measure its impact on activity-travel behavior. As a consequence, there seems no significant change in worker's daily life, other than mitigating traffic congestion due to decreasing commuting travel in the rush hour. The result of VKT (vehicle kilometers traveled) shows an opposite pattern according to given household/individual constraints. The scenario analysis on telecommuting indicates a decreasing trend in both travel frequency and distance because of the diminished number of commuting trips. As the activity space of telecommuters is shifted to a residential area, there are more short-distance trips by using non-motorized transport, which leads to decrease in VKT (using a private vehicle). Thus, the sensitivity of VKT by population groups varies due to transport mode shift (between personal and another mode) and growing non-work trips (using a private mode). This study found few things. First, it is necessary to evaluate the details of policy impact by population groups since it can be varied depending on household/individual characteristics. Second, the case study shows a promising performance of ABM as policy measurement that provides reality in policy evaluation. Third, ABM allows us to do more accurate analysis (i.e. time-series analysis by population groups) of policy assessment than those of FSM (Four-Step Model). Lastly, a further effort in data collection, literature review, and expert survey should be made to enhance the accuracy and confidence of future research.

A Study on Reliability and Applicability of Oriental Medical Music Therapy Using (음악요법의 한의학적 활용을 위한 신뢰도 및 적용 가능성 연구)

  • Song, Min Sun;Choi, Chan Hun
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.28 no.6
    • /
    • pp.674-682
    • /
    • 2014
  • The purpose of this study was to identify the effect of applying oriental music therapy and reliability of electroencephalogram(EEG) equipment. The study was approved by the critical trial judge committee from ${\bigcirc}{\bigcirc}$(IRB No. 2013-07) university. In order to measure test-retest reliability for 15 subjects, EEG for same participants were measured using same method mentioned above after 2 hours from the first measurement. Same provider implemented to each person at same time. Firstly, EEG was measured for 5 minutes after the subject with attached electrodes sat on chair comfortably for 10 minutes. Then, the subject was given mental stress using the four fundamental arithmetic operations for 5 minutes, and measured EEG for another 5 minutes. After that the subject sat on the chair comfortably listening oriental medicine music therapy for 5 minutes, and EEG was measured for 5 minutes again. There was no side effect regarding music therapy reported. Raw data, which was measured in each step, were converted through FFT(fast fourier transform) and analyzed after divided into certain frequency including ${\alpha}$ wave, ${\beta}$ wave, ${\theta}$ wave, immersion wave, stabilization wave, sef100 wave, and sef95 wave. Data were analyzed using wilcoxon signed rank test, Intraclass correlation coefficient(ICC), repeated measures ANOVA with the SPSS program. In test-retes method, there were significantly differences in ${\alpha}$ wave, ${\beta}$ wave, immersion wave, stability wave, ${\theta}$ wave, sef100 wave, sef95 wave. ICC has shown a high degree of reliability that it was ${\alpha}$ wave .877, ${\beta}$ wave .855, ${\gamma}$ wave .895, immersion wave .897, stability wave .816, ${\theta}$ wave .904, sef100 wave .910, sef95 wave .776. Also, there was a statistically significant difference in ${\alpha}$ wave after applying oriental music therapy. Based on these results, it is considered that average of the channel EEG and application of oriental music therapy would be practiced by increase of sample size using this machine.

The Development and Application of Office Price Index for Benchmark in Seoul using Repeat Sales Model (반복매매모형을 활용한 서울시 오피스 벤치마크 가격지수 개발 및 시험적 적용 연구)

  • Ryu, Kang Min;Song, Ki Wook
    • Land and Housing Review
    • /
    • v.11 no.2
    • /
    • pp.33-46
    • /
    • 2020
  • As the fastest growing office transaction volume in Korea, there's been a need for development of indicators to accurately diagnose the office capital market. The purpose of this paper is experimentally calculate to the office price index for effective benchmark indices in Seoul. The quantitative methodology used a Case-Shiller Repeat Sales Model (1991), based on actual multiple office transaction dataset with over minimum 1,653 ㎡ from Q3 1999 to 4Q 2019 in the case of 1,536 buildings within Seoul Metropolitan. In addition, the collected historical data and spatial statistical analysis tools were treated with the SAS 9.4 and ArcGIS 10.7 programs. The main empirical results of research are briefly summarized as follows; First, Seoul office price index was estimated to be 344.3 point (2001.1Q=100.0P) at the end of 2019, and has more than tripled over the past two decades. it means that the sales price of office per 3.3 ㎡ has consistently risen more than 12% every year since 2000, which is far above the indices for apartment housing index, announced by the MOLIT (2009). Second, between quarterly and annual office price index for the two-step estimation of the MIT Real Estate Research Center (MIT/CRE), T, L, AL variables have statistically significant coefficient (Beta) all of the mode l (p<0.01). Third, it was possible to produce a more stable office price index against the basic index by using the Moore-Penrose's pseoudo inverse technique at low transaction frequency. Fourth, as an lagging indicators, the office price index is closely related to key macroeconomic indicators, such as GDP(+), KOSPI(+), interest rates (5-year KTB, -). This facts indicate that long-term office investment tends to outperform other financial assets owing to high return and low risk pattern. In conclusion, these findings are practically meaningful to presenting an new office price index that increases accuracy and then attempting to preliminary applications for the case of Seoul. Moreover, it can provide sincerely useful benchmark about investing an office and predicting changes of the sales price among market participants (e.g. policy maker, investor, landlord, tenant, user) in the future.