• Title/Summary/Keyword: Retention loss

Search Result 330, Processing Time 0.023 seconds

EVALUATION OF HEAT-FLUX DISTRIBUTION AT THE INNER AND OUTER REACTOR VESSEL WALLS UNDER THE IN-VESSEL RETENTION THROUGH EXTERNAL REACTOR VESSEL COOLING CONDITION

  • JUNG, JAEHOON;AN, SANG MO;HA, KWANG SOON;KIM, HWAN YEOL
    • Nuclear Engineering and Technology
    • /
    • v.47 no.1
    • /
    • pp.66-73
    • /
    • 2015
  • Background: A numerical simulation was carried out to investigate the difference between internal and external heat-flux distributions at the reactor vessel wall under in-vessel retention through external reactor vessel cooling (IVR-ERVC). Methods: Total loss of feed water, station blackout, and large break loss of coolant accidents were selected as the severe accident scenarios, and a transient analysis using the element-birth-and-death technique was conducted to reflect the vessel erosion (vessel wall thickness change) effect. Results: It was found that the maximum heat flux at the focusing region was decreased at least 10% when considering the two-dimensional heat conduction at the reactor vessel wall. Conclusion: The results show that a higher thermal margin for the IVR-ERVC strategy can be achieved in the focusing region. In addition, sensitivity studies revealed that the heat flux and reactor vessel thickness are dominantly affected by the molten corium pool formation according to the accident scenario.

Treatment of Acute Transverse Myelitis : a case report (하지마목으로 진단된 환자 치험 1례(例))

  • Kang, Hyung-Won;Lyu, Yeong-Su;Kim, Tae-Heon;Lee, Su-Jeong
    • Journal of Oriental Neuropsychiatry
    • /
    • v.16 no.2
    • /
    • pp.213-221
    • /
    • 2005
  • Acute Transverse Myelitis is a syndrome, not a disease, in which acute inflammation affects gray and white matter in one or more adjacent thoracic segments. Almost all patients will develope ascending weakness and numbness of feet and leg, difficulty voiding, urinary retention, and loss of bowel control. We concluded this case to MAMOK( 마목) due to Qi ascent, Qi deficiency, Qi stoppage(상기, 기허, 기체). So we used herbal medication, acupuncture, and homeopuncture according to oriental medical theory. Weakness and numbness of feet and leg, difficulty voiding, urinary retention, and loss of bowel control are reduced. Herbal medication, acupuncture, and homeopuncture helped the care of this syndrome and further study will be investigated in oriental medicine for this syndrome.

  • PDF

Physical Properties and Dyeing Behaviors of Cotton Fabric Treated with Low Temperature Plasma and/or Cellulase (저온플라즈마 및 효소처리한 면의 물성 및 염색성)

  • Yoon, Nam Sik;Lim, Yong Jin
    • Textile Coloration and Finishing
    • /
    • v.8 no.3
    • /
    • pp.59-65
    • /
    • 1996
  • Cotton fabrics were treated by low temperature plasma and/or cellulase, and its physical and dyeing properties were investigated. All the pretreatments of the cotton with low temperature plasma of oxygen, nitrogen and argon slowed down the rate of weight loss of cotton in cellulase solution. Plasma pretreatment did not show any strength retention effect on cotton fiber in the subsequent cellulase treatment. Pretreatment of cotton with low temperature oxygen plasma decreased the rate of dyeing in direct dye bath, while cellulase or plasma/cellulase pretreatment increased the rate. Equilibrium dye uptake of cotton was not changed greatly by the pretreatments except the normal untreated cotton showed more or less high uptake. The pretreatment of cellulase with a water-soluble carbodiimide reduced the enzymatic activity, and did not show any strength retention of cotton in enzymatic weight loss.

  • PDF

Charge Spreading Effect of Stored Charge on Retention Characteristics in SONOS NAND Flash Memory Devices

  • Kim, Seong-Hyeon;Yang, Seung-Dong;Kim, Jin-Seop;Jeong, Jun-Kyo;Lee, Hi-Deok;Lee, Ga-Won
    • Transactions on Electrical and Electronic Materials
    • /
    • v.16 no.4
    • /
    • pp.183-186
    • /
    • 2015
  • This research investigates the impact of charge spreading on the data retention of three-dimensional (3D) silicon-oxide-nitride-oxide-silicon (SONOS) flash memory where the charge trapping layer is shared along the cell string. In order to do so, this study conducts an electrical analysis of the planar SONOS test pattern where the silicon nitride charge storage layer is not isolated but extends beyond the gate electrode. Experimental results from the test pattern show larger retention loss in the devices with extended storage layers compared to isolated devices. This retention degradation is thought to be the result of an additional charge spreading through the extended silicon nitride layer along the width of the memory cell, which should be improved for the successful 3-D application of SONOS flash devices.

Volatile Retention during Freeze Drying of Fruit Juices (과실쥬스의 동결건조 중 휘발성분 보유력)

  • 심기환;최진상;주옥수;강갑석
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.19 no.6
    • /
    • pp.555-564
    • /
    • 1990
  • The headspace gas chromatographic(analytical) technique was used to evaluate the retention of volatiles in fruit juices during freeze drying as a function of freezing rate, the content of initial solid and chamber pressure. The effects of freezing rate and drying time on the volatile retention under the experimental conditions were marked, particulary at long freezing time. The retention of volatiles in the freeze dried was largely affected by the freezing rate. The highest volatile loss under the freeze drying conditions was observed during the first stage of drying. The behavior during freeze drying of the volatile substances was affected by high content of initial solid. The volatile retention was higher in quick freeze drying than slow freeze drying and low pressure than high.

  • PDF

A Study on the Fluidity Retention of Cement Paste Added by Naphthalene Sulfonated Condensate and Polycarboxylic Acid Admixture (나프탈렌술폰산축합물과 폴리카르본산계 혼화제가 첨가된 시멘트 페이스트의 유동성 유지에 관한 연구)

  • 노재성;홍성수;김도수
    • Magazine of the Korea Concrete Institute
    • /
    • v.7 no.5
    • /
    • pp.189-199
    • /
    • 1995
  • Naphthalene sulfonated condensate has been widely used as a superplasticizer for cement and concrete, but the application was limited due to its large slump loss with elapsed time. To complement this demerit of NSF, polycarboxylic acid copolymer from nlaleic anhydride and acryl~c acid(MA) was synthesized to retain the mobility of cement and concrete, and then mixed with NSF. The physical properties, such as fluidity, fluidityretention and rheology, were measured by applying these admixtures to cement paste as a function of elapsed time. And also compressive strength of mortar was measured with curing time. NIv-l and NM-2 containing 10, 20 wt% of MA respectively had a excellent fluidity and a fluidity- retention. In rheological property, the increases of shear stress and viscosity with elapsed time were delayed with the increasing of shear rate in cornparision with NSF only. The marked slump loss of cement paste could be controlled by these admixture. Also the added ainount of admixture and the ratio of water to cement affected these properties.

Evaluation of citrus fiber as a natural alternative to sodium tripolyphosphate in marinated boneless broiler chicken breast and inside beef skirt (transversus abdominis)

  • Kendal R. Howard;Cheyenne L. Runyan;Allen B. Poe;Andrew M. Cassens;Lea A. Kinman
    • Animal Bioscience
    • /
    • v.37 no.1
    • /
    • pp.116-122
    • /
    • 2024
  • Objective: This research was conducted to evaluate the effects of citrus fiber (CF) as a natural alternative to sodium tripolyphosphate (STPP) in marinated broiler boneless chicken breast and inside beef skirt on overall retention rate, shear force, and consumer sensory attributes. Methods: Five different marinade formulations were targeted to include 0.9% salt, either 0.25% or 0.50% STPP or CF and water on a finished product basis. Water and salt only were considered the negative control (CON). Chicken breasts (n = 14) and inside beef skirt (n = 14) were randomly assigned to a treatment, raw weights recorded and then placed in a vacuum tumbler. Marinated weights were recorded, individually packed, and randomly assigned to either retail display for 10-day retention rate, shear force analysis, cook loss, or consumer sensory panel. Results: Pickup percentage, and overall retention was similar among treatments for chicken breast and inside beef skirt. Citrus fiber treatments resulted in higher cooking loss compared to the CON in chicken breast; though, CF050 resulted in similar cooking loss compared to STPP025 in inside beef skirt. No differences were found in sensory attributes for chicken breast, however, WBSF data showed CF025 was tougher than CF050, STPP050, and CON. Inside beef skirt with CF050 were least liked overall by the consumer panel. Conclusion: Citrus fiber included in marinades at a lower percentage rate can produce similar texture characteristics, and sensory properties compared with those marinated with STPP.

Study of Data Retention Characteristics with surrounding cell's state in a MLC NAND Flash Memory (멀티 레벨 낸드 플레쉬 메모리에서 주변 셀 상태에 따른 데이터 유지 특성에 대한 연구)

  • Choi, Deuk-Sung;Choi, Sung-Un;Park, Sung-Kye
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.50 no.4
    • /
    • pp.239-245
    • /
    • 2013
  • The data retention characteristics depending on neighbor cell's threshold voltage (Vt) in a multilevel NAND flash memory is studied. It is found that a Vt shift (${\Delta}Vt$) of the noted cell during a thermal retention test is increased as the number of erase-state (lowest Vt state) cells surrounding the noted cell increases. It is because a charge loss from a floating gate is originated from not only intrinsic mechanism but also lateral electric field between the neighboring cells. From the electric field simulation, we can find that the electric field is increased and it results in the increased charge loss as the device is scaled down.

Changing C-N Interactions in the Forest Floor under Chronic N Deposition: Implications for Forest C Sequestration

  • Park, Ji-Hyung
    • Journal of Ecology and Environment
    • /
    • v.31 no.3
    • /
    • pp.167-176
    • /
    • 2008
  • Atmospheric N deposition has far-reaching impacts on forest ecosystems, including on-site impacts such as soil acidification, fertilization, and nutrient imbalances, and off-site environmental impacts such as nitrate leaching and nitrous oxide emission. Although chronic N deposition has been believed to lead to forest N saturation, recent evidence suggests that N retention capacity, particularly in the forest floor, can be surprisingly high even under high N deposition. This review aims to provide an overview of N retention processes in the forest floor and the implications of changing C-N interactions for C sequestration. The fate of available N in forest soils has been explained by the competitive balance between tree roots, soil heterotrophs, and nitrifiers. However, high rates of N retention have been observed in numerous N addition experiments without noticeable increases in tree growth and soil respiration. Alternative hypotheses have been proposed to explain the gap between the input and loss of N in N-enriched, C-limited systems, including abiotic immobilization and mycorrhizal assimilation, both of which do not require additional C sources to incorporate N in soil N pools. Different fates of N in the forest floor have different implications for C sequestration. N-induced tree growth can enhance C accumulation in tree biomass as observed across temperate regions. C loss from forests can amount to or outweigh C gain in N-saturated, declining forests, while another type of 'C-N decoupling' can have positive or neutral effects on soil C sequestration through hampered organic matter decomposition or abiotic N immobilization, respectively.

A Study on Threshold Voltage Degradation by Loss Effect of Trapped Charge in IPD Layer for Program Saturation in a MLC NAND Flash Memory (멀티레벨 낸드 플래쉬 메모리 프로그램 포화 영역에서의 IPD 층에 트랩된 전하의 손실 효과에 의한 문턱 전압 저하 특성에 대한 연구)

  • Choi, Chae-Hyoung;Choi, Deuk-Sung;Jeong, Seung-Hyun
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.24 no.3
    • /
    • pp.47-52
    • /
    • 2017
  • This research scrutinizes the data retention characteristics of the MLC NAND Flash Memory instigated by the loss effect of trapped charge when the memory is in the state of program saturation. It is attributed to the threshold voltage saturation phenomenon which engenders an interruption to the linear increase of the voltage in the memory cell. This phenomenon is occasioned by the outflow of the trapped charge from the floating gate to the control gate, which has been programmed by the ISPP (Incremental Step Pulse Programming), via Inter-Poly Dielectric (IPD). This study stipulates the significant degradation of thermal retention characteristics of threshold voltage in the saturation region in contrast to the ones in the linear region. Thus the current study evaluates the data retention characteristics of voltage after the program with a repeated reading test in various measurement conditions. The loss effect of trapped charge is found in the IPD layer located between the floating gate and the control gate especially in the nitride layer of the IPD. After the thermal stress, the trapped charge is de-trapped and displays the impediment of the characteristic of reliability. To increase the threshold saturation voltage in the NAND Flash Memory, the storage ability of the charge in the floating gate must be enhanced with a well-thought-out designing of the module in the IPD layer.