• Title/Summary/Keyword: The carrier

Search Result 6,848, Processing Time 0.039 seconds

A study on Career identity, Satisfaction in major, and Adjustment to college life for students of Department of Food and Nutrition at a University (일 대학 식품영양학과 학생의 진로정체감, 전공만족도 및 대학생활적응에 관한 연구)

  • Lee, Songmi;Cho, Jihyun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.10
    • /
    • pp.6698-6707
    • /
    • 2015
  • The purpose of this study is to investigate relationships among career identity, satisfaction in major, and adjustment to college life for students who major in food and nutrition that is complex and has diversity of carrier and to serve as a guideline for career counselling and college life. After reliability and validity of the data collected were verified using IBM SPSS Statistics 22, difference in variables according to characteristics of students was examined using independent t-test, ANOVA, and chi-square test. The results showed that there was a positive correlation among career identity, satisfaction in major, and adjustment to college life and students who had prior knowledge of their major showed a higher level of career identity, satisfaction in major and adjustment to college life compared to those who did not. Therefore, it is suggested that guidance on Department of Food and Nutrition should be provided to students before they decide on their major for their increased satisfaction in major, smooth adjustment to college life, and career decision. With this data, we recognize the gravity of psychological factor and carrer consciousness may provide base data to practical use of student life and carrer guidance.

A Study on the reflection ratio of ICAO Annex 6 (Operations of Aircraft) incorporated into our domestic air laws - Focused on ICAO Annex 6 Part I (International Commercial Air Transport - Aeroplanes) - (ICAO 부속서 6(항공기 운항)의 국내 항공법령 반영률에 관한 연구 - ICAO Annex 6 Part I (국제상업항공운송-항공기)을 중심으로 -)

  • Noh, Kun-Soo;Jie, Min-Seok;Kim, Woong-Yi
    • The Korean Journal of Air & Space Law and Policy
    • /
    • v.28 no.2
    • /
    • pp.97-115
    • /
    • 2013
  • The world-wide principal criteria of aircraft operations is ICAO Annex 6. Operations of Aircraft. Among ICAO Annex 6, Part I is for International Commercial Air Transport - Aeroplanes and it assumes major part of civil aviation. ICAO has been providing Contracting States with SARPs(Standards and Recommended Practices) and monitor each State's reflection degree into their domestic air law, so-called USOAP(Universal Safety Oversight Audit Program). Current ICAO USOAP is Snap-shot method, but it will be changed to USOAP-CMA method from the year of 2013. ICAO USOAP results have overall effects on national aviation industry such as routes, insurance, airlines cooperation and so forth. Low grades of results attract international attention and that leads to flag carrier's operation stoppage, route restriction, airlines cooperation restriction, insurance increase directly or indirectly. Thus it is important to get excellent grades in ICAO USOAP and to maintain confidence. Our government ranked top to get 98.89 grades in 2008 ICAO USOAP but after 2008 the revised provisions have not been reflected sufficiently into our air law. So I would like to grip reflection ratio of ICAO Annex 6 Part I into our domestic air law by using the most updated revised edition on this paper. Together I would like to suggest alternatives for the non-reflected and partially reflected.

  • PDF

Study of Optical Properties of InxGa1-xN/GaN Multi-Quantum-Well (InxGa1-xN/GaN 다중양자우물 구조의 광학적 성질 연구)

  • Kim, Ki-Hong;Kim, In-Su;Park, Hun-Bo;Bae, In-Ho;Yu, jae-In;Jang, Yoon-Seok
    • Journal of the Korean Vacuum Society
    • /
    • v.18 no.1
    • /
    • pp.37-43
    • /
    • 2009
  • Temperature and injection current dependence of electroluminescence(EL) spectral intensity of the $In_xGa_{1-x}N$/GaN multi-quantum wells(MQW) have been studied over a wide temperature range and as a function of injection current level. It is found that a temperature-dependent variation pattern of the EL efficiency under very low and high injection currents shows a drastic difference. This unique EL efficiency variation pattern with temperature and current can be explained field effects due to the driving forward bias in presence of internal(piezo and spontaneous polarization) fields. Increase of the indium content in $In_xGa_{1-x}N$/GaN multiple quantum wells gives rise to a redshift of 80 meV and 22 meV for green and blue MQW, respectively. It can be explained by carrier localization by potential fluctuation of multiple quantum well and MQW structures also shows a keen difference owing to the different indium content in InGaN/GaN MQW.

Growth of CdS Single Crystal as Photoconductor and Its Physical Characteristics (광전도체의 CdS 단결정 성장과 물리적 특성)

  • Jeong, T.S.;Yu, P.Y.;Shin, Y.J.;Shin, H.K.;Kim, T.S.;Jeong, C.H.;Lee, H.;Shin, Y.S.;Hong, K.J.;Rheu, K.S.
    • Journal of Sensor Science and Technology
    • /
    • v.2 no.1
    • /
    • pp.109-115
    • /
    • 1993
  • A CdS single crystal was grown by using sublimation method. Lattice constants, $a_{o}$ and $c_{o}$, obtained by using extrapolation were $4.131{\underline{8}}{\AA}$ and $6.712{\underline{2}}{\AA}$, respectively. The carrier density was${\sim}10^{23}m^{-3}$ and the mobility was $2.93{\times}10^{-2}m^{2}$/V sec from measured Hall data at room temperature. The mobility has a increasing tendency in proportion to $T^{1/2}$ from 33 K to 150 K and a decreasing tendency in proportion to $T^{-2}$ from 180 K to room temperature. The short wavelength band peak measured from photocurrent was due to intrinsic transition, and the energy value of this peak was equal to the energy band gap of CdS photoconductor.

  • PDF

Review on Free-Standing Polymer and Mixed-Matrix Membranes for H2/CO2 Separation (수소/이산화탄소 분리를 위한 프리스탠딩 고분자 및 혼합매질 분리막에 대한 총설)

  • Kang, Miso;Lee, So Youn;Kang, Du Ru;Kim, Jong Hak
    • Membrane Journal
    • /
    • v.32 no.4
    • /
    • pp.218-226
    • /
    • 2022
  • Hydrogen, a carrier of large-capacity chemical and clean energy, is an important industrial gas widely used in the petrochemical industry and fuel cells. In particular, hydrogen is mainly produced from fossil fuels through steam reforming and gasification, and carbon dioxide is generated as a by-product. Therefore, in order to obtain high-purity hydrogen, carbon dioxide should be removed. This review focused on free-standing polymeric membranes and mixed-matrix membranes (MMMs) that separate hydrogen from carbon dioxide reported in units of Barrer [1 Barrer = 10-10 cm3 (STP) × cm / (cm2 × s × cmHg)]. By analyzing various recently reported papers, the structure, morphology, interaction, and preparation method of the membranes are discussed, and the structure-property relationship is understood to help find better membrane materials in the future. Robeson's upper bound limits for hydrogen/carbon dioxide separation were presented through reviewing the performance and characteristics of various separation membranes, and various MMMs that improve separation properties using technologies such as crosslinking, blending and heat treatment were discussed.

Research Trend of Direct Ammonia Anion - Exchange Membrane Fuel Cells (직접 암모니아 음이온 교환막 연료전지 연구 동향)

  • Seonyeob Kim;Ji Eon Chae;Jiseon Choi;Sunyeop Lee;Cheolwoong Park
    • Journal of the Korean Institute of Gas
    • /
    • v.27 no.3
    • /
    • pp.41-51
    • /
    • 2023
  • As abnormal climatic event occur frequently due to global warming, many nations have proclaimed their commitment to achieving carbon neutrality and are actively pursuing a transition toward a hydrogen economy. At this time, ammonia has garnered significant attention not only as a high-capacity hydrogen carrier but also as a promising candidate as a carbon-free fuel. In particular, anion exchange membrane fuel cells offer the advantage of directly supplying ammonia to the fuel cell, eliminating the necessity for separate ammonia decomposition or hydrogen purification. Therefore, in this study, the operation principle and research trend of the anion exchange membrane fuel cell are reviewed, and several research using ammonia as a fuel in anion exchange membrane fuel cell are also investigated.

A neonate with hyperornithinemia-hyperammonemia-homocitrullinuria syndrome from a consanguineous Pakistani family

  • Kim, Yoo-Mi;Lim, Han Hyuk;Gang, Mi Hyeon;Lee, Yong Wook;Kim, Sook Za;Kim, Gu-Hwan;Yoo, Han-Wook;Ko, Jung-Min;Chang, Meayoung
    • Journal of Genetic Medicine
    • /
    • v.16 no.2
    • /
    • pp.85-89
    • /
    • 2019
  • Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a rare autosomal recessive urea cycle disorder. HHH is caused by a deficiency of the mitochondrial ornithine transporter protein, which is encoded by the solute carrier family 25, member 15 (SLC25A15) gene. Recently, government supported Korean newborn screening has been expanded to include a tandem mass spectrometry (MS/MS) measurement of ornithine level. We report a case of a neonate with HHH syndrome showing a normal MS/MS measurement of ornithine level. A female newborn was admitted to neonatal intensive unit due to familial history of HHH syndrome. Her parents were consanguineous Parkistani couple. The subject's older sister was diagnosed with HHH syndrome at age of 30 months based on altered mental status and liver dysfunction. Even though the subject displayed normal ammonia and ornithine levels based on MS/MS analysis, a molecular test confirmed the diagnosis of HHH syndrome. At 1 month of age, amino acid analysis of blood and urine showed high levels of ornithine and homocitrulline. After 11 months of follow up, she showed normal growth and development, whereas affected sister showed progressive cognitive impairment despite no further hyperammonemia after protein restriction and standard therapy. Our report is in agreement with a previous Canadian study, which showed that neonatal samples from HHH syndrome patients demonstrate normal ornithine levels despite having known mutations. Considering the delayed rise of ornithine in affected patients, genetic testing, and repetitive metabolic testing is needed to prevent patient loss in high risk patients.

Sequential Analysis of Hepatitis Be Antigen Status in Infants Born to Hepatitis Be Antigen-Positive Mothers (HBe항원 양성 산모에서 출생한 HBe항원 양성인 신생아의 추적관찰)

  • Park, Eun Sook;Lee, Hae Kyung;Oh, Chang Hee;Kim, Sung Ku;Yun, Hae Sun;Song, Won Keun;Lee, Young Ah
    • Clinical and Experimental Pediatrics
    • /
    • v.45 no.6
    • /
    • pp.727-731
    • /
    • 2002
  • Purpose : The objectives of this study are to evaluate the significance of HBeAg positivity in infants born to HBeAg and HBsAg positive mothers. Methods : The HBeAg status of 22 HBeAg positive, HBsAg negative infants born to HBeAg and HBsAg positive mothers from December 1996 to March 1999 were evaluated by enzyme immunoassay. Results : The number of HBsAg positive carrier mothers was 213(4.9%) out of 4,338 pregnant women. HBeAg was positive in 76(41.5%) out of 183 HBsAg positive mothers. Only 49 infants born to 76 HBeAg positive mothers could be evaluated; 36 infants were HBeAg positive and HBsAg negative. Laboratory follow up was possible in 22 infants. HBeAg disappeared in 7 cases within two months and in 20 cases within 12 months(over 90%). Ultimately, twenty-two babies who were HBsAg-negative and HBeAg-positive became negative for HBeAg, however, one showed HBsAg in follow up of 6 months of age. Conclusion : HBeAg positivity in infants born to HBeAg positive mothers may result from the maternofetal transmission and this HBeAg eventually disappeared without clinical significance.

Physicochemical Characteristics of Fe3O4 Magnetic Nanocomposites Based on Poly(N-isopropylacrylamide) for Anti-cancer Drug Delivery

  • Davaran, Soodabeh;Alimirzalu, Samira;Nejati-Koshki, Kazem;Nasrabadi, Hamid Tayefi;Akbarzadeh, Abolfazl;Khandaghi, Amir Ahmad;Abbasian, Mojtaba;Alimohammadi, Somayeh
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.1
    • /
    • pp.49-54
    • /
    • 2014
  • Background: Hydrogels are a class of polymers that can absorb water or biological fluids and swell to several times their dry volume, dependent on changes in the external environment. In recent years, hydrogels and hydrogel nanocomposites have found a variety of biomedical applications, including drug delivery and cancer treatment. The incorporation of nanoparticulates into a hydrogel matrix can result in unique material characteristics such as enhanced mechanical properties, swelling response, and capability of remote controlled actuation. Materials and Methods: In this work, synthesis of hydrogel nanocomposites containing magnetic nanoparticles are studied. At first, magnetic nanoparticles ($Fe_3O_4$) with an average size 10 nm were prepared. At second approach, thermo and pH-sensitive poly (N-isopropylacrylamide -co-methacrylic acid-co-vinyl pyrrolidone) (NIPAAm-MAA-VP) were prepared. Swelling behavior of co-polymer was studied in buffer solutions with different pH values (pH=5.8, pH=7.4) at $37^{\circ}C$. Magnetic iron oxide nanoparticles ($Fe_3O_4$) and doxorubicin were incorporated into copolymer and drug loading was studied. The release of drug, carried out at different pH and temperatures. Finally, chemical composition, magnetic properties and morphology of doxorubicin-loaded magnetic hydrogel nanocomposites were analyzed by FT- IR, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM). Results: The results indicated that drug loading efficiency was increased by increasing the drug ratio to polymer. Doxorubicin was released more at $40^{\circ}C$ and in acidic pH compared to that $37^{\circ}C$ and basic pH. Conclusions: This study suggested that the poly (NIPAAm-MAA-VP) magnetic hydrogel nanocomposite could be an effective carrier for targeting drug delivery systems of anti-cancer drugs due to its temperature sensitive properties.

Analysis of Channel Doping Profile Dependent Threshold Voltage Characteristics for Double Gate MOSFET (이중게이트 MOSFET의 채널도핑분포의 형태에 따른 문턱전압특성분석)

  • Jung, Hak-Kee;Han, Ji-Hyung;Lee, Jae-Hyung;Jeong, Dong-Soo;Lee, Jong-In;Kwon, Oh-Shin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2011.05a
    • /
    • pp.664-667
    • /
    • 2011
  • In this paper, threshold voltage characteristics have been analyzed as one of short channel effects occurred in double gate(DG)MOSFET to be next-generation devices. The Gaussian function to be nearly experimental distribution has been used as carrier distribution to solve Poisson's equation, and threshold voltage has been investigated according to projected range and standard projected deviation, variables of Gaussian function. The analytical potential distribution model has been derived from Poisson's equation, and threshold voltage has been obtained from this model. Since threshold voltage has been defined as gate voltage when surface potential is twice of Fermi potential, threshold voltage has been derived from analytical model of surface potential. Those results of this potential model are compared with those of numerical simulation to verify this model. As a result, since potential model presented in this paper is good agreement with numerical model, the threshold voltage characteristics have been considered according to the doping profile of DGMOSFET.

  • PDF