• 제목/요약/키워드: Secondary cell

검색결과 991건 처리시간 0.032초

이차전지와 보호회로의 기술 동향 (Technolgy trends for secondary battery cell and protection circuit)

  • 변재인;김학수
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2014년도 춘계학술대회
    • /
    • pp.752-754
    • /
    • 2014
  • 노트북, 핸드폰, 디지털기기와 같은 휴대용기기의 급속한 발달과 함께 2차전지의 중요성이 점점 증가하고 있다. 근래에 들어서 반도체산업, 디스플레이기술, 2차전지가 3대 핵심 산업으로 여겨지고 있다. 특히, 스마트폰은 고성능화 되어가고 있지만, 2차전지가 따라가지 못하는 추세이다. 최근에는 배터리의 의한 발열로 인한 안정성 문제가 대두되었다. 본 논문에서는 이차전지와 보호회로에 대한 기술 동향을 조사 정리한다.

  • PDF

Disorders of Secondary Neurulation : Mainly Focused on Pathoembryogenesis

  • Yang, Jeyul;Lee, Ji Yeoun;Kim, Kyung Hyun;Wang, Kyu-Chang
    • Journal of Korean Neurosurgical Society
    • /
    • 제64권3호
    • /
    • pp.386-405
    • /
    • 2021
  • Recent advancements in basic research on the process of secondary neurulation and increased clinical experience with caudal spinal anomalies with associated abnormalities in the surrounding and distal structures shed light on further understanding of the pathoembryogenesis of the lesions and led to the new classification of these dysraphic entities. We summarized the changing concepts of lesions developed from the disordered secondary neurulation shown during the last decade. In addition, we suggested our new pathoembryogenetic explanations for a few entities based on the literature and the data from our previous animal research. Disordered secondary neurulation at each phase of development may cause corresponding lesions, such as failed junction with the primary neural tube (junctional neural tube defect and segmental spinal dysgenesis), dysgenesis or duplication of the caudal cell mass associated with disturbed activity of caudal mesenchymal tissue (caudal agenesis and caudal duplication syndrome), failed ingression of the primitive streak to the caudal cell mass (myelomeningocele), focal limited dorsal neuro-cutaneous nondisjunction (limited dorsal myeloschisis and congenital dermal sinus), neuro-mesenchymal adhesion (lumbosacral lipomatous malformation), and regression failure spectrum of the medullary cord (thickened filum and filar cyst, low-lying conus, retained medullary cord, terminal myelocele and terminal myelocystocele). It seems that almost every anomalous entity of the primary neural tube may occur in the area of secondary neurulation. Furthermore, the close association with the activity of caudal mesenchymal tissue in secondary neurulation involves a wider range of surrounding structures than in primary neurulation. Although the majority of the data are from animals, not from humans and many theories are still conjectural, these changing concepts of normal and disordered secondary neurulation will provoke further advancements in our management strategies as well as in the pathoembryogenetic understanding of anomalous lesions in this area.

랑게르한스세포 조직구증 환아에서 발생한 속발성 경화성 담관염 1례 (A Case of Secondary Sclerosing Cholangitis in Langerhans Cell Histiocytosis)

  • 김자형;최보화;김경모;문형남
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • 제4권1호
    • /
    • pp.120-124
    • /
    • 2001
  • 저자들은 복부 팽만과 지속적인 황달을 주소로 내원한 랑게르한스세포 조직구증 환아에서 간조직 검사 및 내시경적 역행성 담도조영술로 진단한 속발성 경화성 담관염 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

  • PDF

출토고목재의 수종과 조직구조에 관한 연구( II ) -출토고목재의 부후형태- (Species identification and microscopic structure of ancient wood excavated from the remains( II ) -Degradation of ancient woods-)

  • 강애경;박상진
    • 보존과학회지
    • /
    • 제2권2호
    • /
    • pp.15-24
    • /
    • 1993
  • To understand the morphological change of ancient woods, samples classified by cell type, burial environment and species were collected and observed using microscopy. Decay of wood by cell type could classified into two types. First, degraded secondary wall was formed granular residues in $S_2$ layer and was remained $S_3$ layer and compound middle lamella. Second, the cell wall was slightly degraded and cracked in secondary wall. A gradual thinning of cell wall was occured. The compound middle lamella was separated from secondary wall. The resistance of degradation is increased at vessels, parenchyma, and tracheid and wood fiber in the order named. The type of degradation by species could be classified into four types. Overall degradation type; the degradation of cell wall is usually heavy and the extent of degradation Varies by part of the same sample. Partial degradation type ; this type shows severely different decay type by part of the sample. Nondegraded cells were mixed with degraded cells on the same sample. Erose degradation type ; thinning of the cell wall was occoured and the degradation type was different by part. Slight degradation types ; secondary wall was slightly degraded, cracked and separated from compound middle lamella. Considering different type of burial environment, dry wood was similiar to sound wood and slightly decayed. Waterlogged and peat burial wood was heavilydecayed. Between species of under the same environment, decay type and extent were diferentiated from each other.

  • PDF

Cell Wall Structure of Various Tropical Plant Waste Fibers

  • Abdul Khalil, H.P.S.;Siti Alwani, M.;Mohd Omar, A.K.
    • Journal of the Korean Wood Science and Technology
    • /
    • 제35권2호
    • /
    • pp.9-15
    • /
    • 2007
  • A comparative study of the structure and organization of the primary and secondary walls in different types of tropical plant waste fibers was carried out using transmission electron microscopy (TEM). The thickness of each layer was also measured using Image Analyzer. TEM micrographs haveconfirmed that cell wall structure of all six types of tropical plant waste fibers (empty fruit bunch, oil palm frond, oil palm trunk, coir, banana stem and pineapple leaf) has the same ultrastructure with wood fibre. The fibers consisted of middle lamella, primary and thick secondary wall with different thickness for different types of fibers. The secondary wall was differentiated into a $S_1$ layer, a unique multi-lamellae $S_2$ layer, and $S_3$ layer.

등칡의 2기목부요소의 발생학적 변이 (Development Changes of the Secondary Xylem Elements in Aristolochia manshuriensis Komarov)

    • 한국자원식물학회지
    • /
    • 제11권3호
    • /
    • pp.319-325
    • /
    • 1998
  • The developmental changes occuring in the secondary xylem of Aristolochia manshuriensis Komarov have been studied in different ages of vine stems. A. manshuriensis possesses typical storeyed cambium comprising both vertically elongated fusiform initials and almost isodiametric ray cell initials. Stems of A. manshuriensis have wide rays that make the secondary xylem appear dissected as other vine types. The length of vessel member and fiber remained relatively constant throughout the secondary growth. However, vessel diameter increases with the increasing age of stem till the cell reaches their maximum limit and later more or less stabilize in diameter while number of vessel per $\textrm{mm}^2$ is vice versa. Width and relative proportion of ray to axial elements gradually increased with the increasing age of stem and later remained relatively constant.

  • PDF

연료전지기반 공동주택 에너지시스템 분석모델에 관한 기초연구 (A Preliminary Study on the Analysis Model of Energy System based on Fuel Cell for Apartment Houses)

  • 이홍철;황인주
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 추계학술대회
    • /
    • pp.396-401
    • /
    • 2003
  • In the present study, preliminary investigation were carried out by analysis of energy system(heat and electricity) based on phosphoric acid fuel-cell of 50 kW for eco-apartment houses. Analysis model were consisted of fuel cell energy system, secondary energy unit and residential building of 5 stories with 20 and 40 households. And the investigation results reviewed under load pattern of heat and electric power of the apartment houses. The results showed mismatch between the needed heat load pattern and output of fuel cell energy system. The mismatch rate were assessed about 10-180% of heat load for apartment houses with season. We found that secondary energy unit are needed in order to supply insufficient heat.

  • PDF

Characterization of the KG1a Cell Line for Use in a Cell Migration Based Screening Assay

  • Bernhard O. Palsson;Karl francis;Lee, Gyun-Min
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • 제7권3호
    • /
    • pp.178-184
    • /
    • 2002
  • High-throughput screening has become a popular method used to identify new “leads”for potentially therapeutic compounds. Further screening of these lead compounds is typically done with secondary assays which may utilize living, functioning cells as screening tools. A problem (or benefit) with these cell-based assays is that living cells are very sensitive to their environment. We have been interested in the process of stem cell migration and how it relates to the cellular therapy of bone marrow transplantation. In this study we describe a secondary, cell-based assay for screening the effects of various in-vitro conditions on Immature Hematopoietic Cell (IHC) migration. Our results have revealed many subtle factors, such as the cell's adhesive characteristics, or the effect of a culture's growth phase, that need to be accounted for in a screening protocol. Finally, we show that exponentially glowing KG1a cells (a human IHC cell line) were 10 times more motile than those in the lag or stationary phases. These data strongly suggest that KG1a cells secrete a chemokinetic factor during the exponential growth phase of a culture.

수용성 전해질을 이용한 이산화망간 2차 전지에 대한 고찰 (Survey on rechargeable battery of MnO2-Zn using aqueous solution)

  • 박석준;신희성;김영철;오창섭
    • 에너지공학
    • /
    • 제25권4호
    • /
    • pp.245-250
    • /
    • 2016
  • 이산화망간은 전지의 활성물질로서 우수한 특성을 가지고 있고 가격도 저렴한 재료로서 각종 1차전지에 사용되어왔다. 그러나 이산화망간을 이용한 2차 전지에 대한 연구는 그렇게 많지 않다. 최근 이산화망간의 충전가역성에 관하여 황산아연을 전해질로 하는 이산화망간 아연전지가 재충전이 가능하다는 보고가 있다. 여기서는 이산화망간이 황산아연수용액 중에서 가역적으로 충전방전이 가능한 것을 토대로 2차전지로서의 가능성에 대해 서술한다.

이차전지 수분 제거용 유도가열 양산 시스템 개발에 관한 연구 (A Study on the Development of Induction Heating Mass Production System for Moisture Removal of Secondary Battery)

  • 지완근;김성환;정해영;이석현
    • 한국전기전자재료학회논문지
    • /
    • 제36권1호
    • /
    • pp.42-48
    • /
    • 2023
  • Abstract: In this study, an induction heating system using resonance is developed to remove remaining moisture and contaminations which could be generated during fabricating secondary batteries. This system is composed of power supply and induction coil. Power supply needs an oscillator, zero crossing detection, frequency tracking function, and induction coil needs a dummy coil to obtain a uniform temperature distribution. It is very important to obtain a uniform heating temperature distribution of battery cell case in the induction heating system before pouring electrolyte into battery cell. Experimental results show a temperature distribution deviation of below 1℃ in the external position of battery cell cases. As well, the temperature of battery cell itself shows distribution of 40℃±3℃.