• 제목/요약/키워드: Specific capacity

검색결과 1,547건 처리시간 0.032초

활성 글루텐 첨가가 쌀베이글의 품질 특성에 미치는 영향 (Effect of Active Gluten Supplementation on the Processing and Quality of Rice Bagel)

  • 이영택;박영서
    • 산업식품공학
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    • 제13권1호
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    • pp.50-55
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    • 2009
  • 활성 글루텐 첨가가 쌀베이글의 품질 특성에 미치는 영향을 조사하였다. 쌀가루에 글루텐 첨가량이 증가함에 따라 보수력은 증가한 반면, 알칼리수 흡수율은 감소하였다. Pelshenke값과 침전가는 글루텐의 첨가량이 증가함에 따라서 유의적으로 증가는 하였으나 강력분의 Pelshenke값과 침전가에는 미치지 못하였다. 최고점도와 setback 및 peak height와 peak width는 글루텐의 첨가량이 증가함에 따라서 감소하는 경향을 보였다. 글루텐을 23% 첨가할 경우 베이글의 부피는 글루텐 11% 첨가 후와 비교할 때 2배 이상 증가하였으며 글루텐의 첨가량이 증가할수록 베이글의 경도, 검성 및 씹힘성은 감소하는 경향을 나타내었다. 베이글의 비용적과 물 흡수력, Pelshenke값 및 침전가와는 고도의 정의 상관(r =0.962, r =0.964, r =0.966)을 나타내었다.

의사 커패시터를 위한 WS2 나노입자가 내제된 탄소나노섬유 (WS2 Nanoparticles Embedded in Carbon Nanofibers for a Pseudocapacitor)

  • 성기욱;이정수;이태근;안효진
    • 한국재료학회지
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    • 제31권8호
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    • pp.458-464
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    • 2021
  • Tungsten disulfide (WS2), a typical 2D layerd structure, has received much attention as a pseudocapacitive material because of its high theoretical specific capacity and excellent ion diffusion kinetics. However, WS2 has critical limits such as poor long-term cycling stability owing to its large volume expansion during cycling and low electrical conductivity. Therefore, to increase the high-rate performance and cycling stability for pseudocapacitors, well-dispersed WS2 nanoparticles embedded in carbon nanofibers (WS2-CNFs), including mesopores and S-doping, are prepared by hydrothermal synthesis and sulfurizaiton. These unique nanocomposite electrodes exhibit a high specific capacity (159.6 F g-1 at 10 mV s-1), excellent high-rate performance (81.3 F g-1 at 300 mV s-1), and long-term cycling stability (55.9 % after 1,000 cycles at 100 mV s-1). The increased specific capacity is attributed to well-dispersed WS2 nanoparticles embedded in CNFs that the enlarge active area; the increased high-rate performance is contributed by reduced ion diffusion pathway due to mesoporous CNFs and improved electrical conductivity due to S-doped CNFs; the long-term cycling stability is attributed to the CNFs matrix including WS2 nanoparticles, which effectively prevent large volume expansion.

활엽수 낙엽의 수분저류 특성에 대한 실험적 분석 (Experimental Analysis of Water Retention Characteristics in the Litter of Different Deciduous Trees)

  • ;최형태;이은재;임상준
    • 한국환경복원기술학회지
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    • 제19권2호
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    • pp.83-93
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    • 2016
  • This study purposed to examine the water retention capacity of floor litter in deciduous forests. Water holding capacity(WHC) and interception storage capacity of Alnus hirsuta Turcz. ex Rupr., Quercus acutissima, Quercus mongolica litters were experimentally estimated. Physical characteristics of litters were also obtained to understand the relationships between water-retention capacity and litter characteristics. Experiments showed that WHC increases with specific volume of litter, varying 244.4% to 416.8% of its dry mass. Interception storage have estimated with rainfall simulation experiments. Maximum interception storage ($C_{max}$) and minimum interception storage ($C_{min}$) of litters were 220% and 138% of dry mass in Alnus hirsuta Turcz. ex Rupr., 218% and 137% in Quercus acutissima, and 240% and 156% in Quercus mongolica. Both $C_{max}$ and $C_{min}$ increased linearly with litter mass, and the values of $C_{min}$ in broadleaf litters have also linear relation to leaf area.

서울 남산과 강원도 백적산의 신갈나무 숲에서 엽록소 함량 및 광합성능의 비교 (Comparison of Pigment Content and Photosynthetic Capacity of Quercus mongolica Stands at Namsan, Seoul and Paekcheoksan, Kangwondo)

  • 임병선;김종욱;이규송;이점숙;김준호;이창석
    • The Korean Journal of Ecology
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    • 제26권5호
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    • pp.267-271
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    • 2003
  • 서울 남산과 강원도 백적산의 신갈나무 숲의 잎의 광합성 색소함량, 광합성능 및 증산율을 현장에서 측정하여 비교하였다. 서울 남산의 신갈나무의 광합성능, 광합성 색소함량 및 비엽면적이 강원도 백적산의 것보다 낮았다 신갈나무 잎의 광합성 색소함량은 6월초에 강원도 백적산보다 서울 남산이 많았으나 그 이후에 후자에서 적었고 두 지역 모두 시간이 경과함에 따라 감소하는 경향을 보였다. 8월 이후에 서울 남산의 신갈나무 잎의 일부에서 반점이 출현하였다. 비엽면적은 서울 남산의 것에서 작았다. 잎의 광합성능은 서울 남산에서 7∼9 월에 더 낮았다.

Improvement of tip analysis model for drilled shafts in cohesionless soils

  • Chen, Yit-Jin;Wu, Hao-Wei;Marcos, Maria Cecilia M.;Lin, Shiu-Shin
    • Geomechanics and Engineering
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    • 제5권5호
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    • pp.447-462
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    • 2013
  • An analysis model for predicting the tip bearing capacity of drilled shafts in cohesionless soils is improved in this study. The evaluation is based on large amounts of drilled shaft load test data. Assessment on the analysis model reveals a greater variation in two coefficients, namely, the overburden bearing capacity factor ($N_q$) and the bearing capacity modifier for soil rigidity (${\zeta}_{qr}$). These factors are modified from the back analysis of drilled shaft load test results. Different effective shaft depths and interpreted capacities at various loading stages (i.e., low, middle, and high) are adopted for the back calculation. Results show that the modified bearing capacity coefficients maintain their basic relationship with soil effective friction angle ($\bar{\phi}$), in which the $N_q$ increases and ${\zeta}_{qr}$ decreases as $\bar{\phi}$ increases. The suggested effective shaft depth is limited to 15B (B = shaft diameter) for the evaluation of effective overburden pressure. Specific design recommendations for the tip bearing capacity analysis of drilled shafts in cohesionless soils are given for engineering practice.

고 Mn 오스테나이트계 스테인리스강의 감쇠능에 미치는 역변태의 영향 (Effect of Reverse Transformation on the Damping Capacity of High Manganease Austenitic Stainless Steel)

  • 강창룡
    • 동력기계공학회지
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    • 제16권4호
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    • pp.60-65
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    • 2012
  • This study was carried out to investigate the effect of reverse transformation on the damping capacity in high manganese austenitic stainless steel. ${\alpha}^{\prime}$-martensite was formed with the specific direction and surface relief by deformation. Over 95% of the austenite phase was transformed to deformation-induced ${\alpha}^{\prime}$-martensite by 70% cold rolling. Reverse transformation became rapid above an annealing temperature of $550^{\circ}C$, but there was no significant transformation above $700^{\circ}C$. In addition, with increasing annealing time at $700^{\circ}C$, reverse transformation was induced rapidly, but the transformation was almost completed at 10 min. Damping capacity was increased up to $700^{\circ}C$, and than unchanged with the increasing annealing temperature. Damping capacity increased steeply with an increasing reverse treatment time up to 10min, whereas there were no significant change with a treatment time of more than 10 min. Damping capacity increased with an increasing the reversed austenite and was strongly affected by reversed austenite.

열간 압연 후 어닐링처리한 Mg 합금의 인장강도와 감쇠능과의 관계 (Relationship between Tensile Strength and Damping Capacity of Annealed Magnesium Alloys after Hot Rolling)

  • 이규현;오은지;김권후;김재남;강창룡
    • 열처리공학회지
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    • 제27권6호
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    • pp.295-301
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    • 2014
  • In this study, the relationship between strength and damping capacity of annealed magnesium alloys after hot rolling was investigated. The microstructure of hot rolled magnesium consisted of dendrite structure and $Mg_{17}Al_{12}$ compounds precipitated along the grain boundary. The dendrite structure was dissipated, $Mg_{17}Al_{12}$ compounds was decomposed by annealing, and then its dissolved in ${\alpha}$-Mg. With an increasing the annealing temperature and time, strength was slowly decreased and damping capacity was slowly increased by the growth of grain size and decreasing of defects induced by hot rolling. In annealing treatmented magnesium alloys after hot rolling, damping capacity was decreased rapidly with an increase of strength. There was on proportional relationship between tensile strength, and damping capacity.

Channel Capacity Analysis of DNA-based Molecular Communication with Length Encoding Mechanism

  • Xie, Jialin;Liu, Qiang;Yang, Kun;Lin, Lin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권8호
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    • pp.2923-2943
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    • 2021
  • The double helix structure of DNA makes it diverse, stable and can store information with high density, and these characteristics are consistent with the requirements of molecular communication for transport carriers. In this paper, a specific structure of molecular communication system based on DNA length coding is proposed. Transmitter (Tx) adopts the multi-layer golden foil design to control the release of DNA molecules of different lengths accurately, and receiver (Rx) adopts an effective and sensitive design of nanopore, and the biological information can be converted to the electric signal at Rx. The effect of some key factors, e.g., the length of time slot, transmission distance, the number of releasing molecules, the priori probability, on channel capacity is demonstrated exhaustively. Moreover, we also compare the transmission capacity of DNA-based molecular communication (DNA-MC) system and concentration-based molecular communication (MC) system under the same parameter setting, and the peak value of capacity of DNA-MC system can achieve 0.08 bps, while the capacity of MC system remains 0.025 bps. The simulation results show that DNA-MC system has obvious advantages over MC system in saving molecular resources and improving transmission stability.

Seismic capacity re-evaluation of the 480V motor control center of South Korea NPPs using earthquake experience and experiment data

  • Choi, Eujeong;Kim, Min Kyu;Choi, In-Kil
    • Nuclear Engineering and Technology
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    • 제54권4호
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    • pp.1363-1373
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    • 2022
  • The recent seismic events that occurred in South Korea have increased the interest in the re-evaluation of the seismic capacity of nuclear power plant (NPP) equipment, which is often conservatively estimated. To date, various approaches-including the Bayesian method proposed by the United States (US) Electric Power Research Institute -have been developed to quantify the seismic capacity of NPP equipment. Among these, the Bayesian approach has advantages in accounting for both prior knowledge and new information to update the probabilistic distribution of seismic capacity. However, data availability and region-specific issues exist in applying this Bayesian approach to Korean NPP equipment. Therefore, this paper proposes to construct an earthquake experience database by combining available earthquake records at Korean NPP sites and the general location of equipment within NPPs. Also, for the better representation of the seismic demand of Korean earthquake datasets, which have distinct seismic characteristics from those of the US at a high-frequency range, a broadband frequency range optimization is suggested. The proposed data construction and seismic demand optimization method for seismic capacity re-evaluation are demonstrated and tested on a 480 V motor control center of a South Korea NPP.

제주도 서반부의 대수층 체계와 지진에 의한 지하수위 변동 특성 (Characteristics of Aquifer System and Change of Groundwater Level due to Earthquake in the Western Half of Jeju Island)

  • 옥순일;함세영;김봉상;정재열;우남칠;이수형;고기원;박윤석
    • 자원환경지질
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    • 제43권4호
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    • pp.359-369
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    • 2010
  • 본 연구는 서반부지역(북서부 소지역, 서부 소지역, 남서부 소지역)에 광역상수도용 수원지 개발을 위하여 굴착된 지하수공을 중심으로 대수층 체계를 분류하고, 수리지질 특성을 규명하였다. 북서부 소지역의 대수층 체계는 상부 투수층-상부 저투수층-하부 투수층-하부 저투수층으로 구성되고, 서부 소지역과 남서부 소지역의 대수층 체계는 상부 저투수층-투수층-하부 저투수층으로 구성된다. 투수량계수와 비양수량은 북서부 소지역, 서부 소지역, 남서부 소지역의 순으로 낮아진다. 비양수량과 응회암의 산출 고도는 비교적 높은 반비례 관계(상관계수 -0.848)를 보이며, 이는 응회암이 대수층의 밑바닥 역할을 하기 때문으로 판단된다. 3개 소지역에 대해서 2004년 수마트라 지진에 의한 지하수위 변동 분석결과, 북서부 소지역에서 평균 23.74 cm로 가장 크며, 서부 소지역에서는 평균 9.48 cm이고, 남서부 소지역 에서는 지하수위 변동이 나타나지 않았다. 그리고 지진에 의한 지하수위 변화는 투수량계수 및 비양수량과 정비례관계를 가지는 것으로 나타났다.