• 제목/요약/키워드: school transitions

검색결과 171건 처리시간 0.027초

차세대 컨테이너크레인에 대한 고찰 (A Study on Future Container Cranes)

  • 정현수;이숙재;홍금식
    • 한국항해항만학회지
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    • 제29권3호
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    • pp.291-298
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    • 2005
  • 본 기술논문에서 18,000 TEU급 초대형 선박에 대응하는 차세대 컨테이너크레인의 규격 및 성능을 검토하였다. 컨테이너선의 발달 과정을 연대순으로 살핀 후에 기존에 설치되어 운영중인 컨테이너크레인의 특성을 파악하였고 세계각처에서 수행되고 있는 컨테이너크레인에 관한 연구동향을 분석하였다. 분석한 결과를 토대로 2014년 이후에 등장할 차세대 컨테이너크레인의 규모 및 성능을 예측하였다. 검토된 사항은 컨테이너크레인의 구조, 트롤리와 호이스트의 메커니즘, 제어방식, 아웃리치, 백리치, 레일게이지, 하역능력, 안정성 및 내구성 등이다.

Innovative Mechanisms in the Procurement Logistics of Kazakhstan

  • Zhatkanbaev, Erzhan B.;Mukhtar, Ernur S.;Suyunchaliyeva, Maiya M.
    • The Journal of Asian Finance, Economics and Business
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    • 제2권3호
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    • pp.33-36
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    • 2015
  • Innovations in the procurement logistics now is very popular in Kazakhstan. Nowadays there are a lot of documents of transport infrastructure and Kazakhstan logistic system is developing more and more. Procurement logistic is the direction where you can count, sometimes you can buy some products or transport equipments. Logistic in Kazakhstan is new direction, there are a lot of young people who choose this specialty and will stay demanded. Our president said a lot of words in strategies about development in logistics and so there will be new methods that will be used here. Innovations are new technologies that are used in different spheres so this structure as procurement logistic will develop in Kazakhstan and every citizen of our republic will support it. Transport systems are used for transitions different products so there are a lot new transition roads for example Western China - Western Europe; Astana-Almaty; Astana-Ust-Kamenogorsk; Astana-Aktobe, Atyrau; Almaty - Ust-Kamenogorsk; Karaganda - Zhezkazgan - Kyzylorda; Atyrau-Astrakhan, it helps Kazakhstan to support international links between other countries.

The Allosteric Transition of the Chaperonin GroEL from Escherichia coli as Studied by Solution X-Ray Scattering

  • Kuwajima Kunihiro;Inobe Tomonao;Arai Munehito
    • Macromolecular Research
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    • 제14권2호
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    • pp.166-172
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    • 2006
  • This is a short review article of our recent studies on the ATP-induced, allosteric conformational transition of the chaperonin GroEL complex by solution X-ray scattering. We used synchrotron X-ray scattering with a two-dimensional, charge-coupled, device-based X-ray detector to study (1) the specificity of the chaperonin GroEL for its ligand that induced the allosteric transition, and (2) the identification of the allosteric transition of GroEL in its complicated kinetics induced by ATP. Due to the dramatically increased sensitivity of the X-ray scattering technique based on the use of the two dimensional X-ray detector and synchrotron radiation, different allosteric conformational states of GroEL populated under different conditions were clearly distinguished from each other. It was concluded that solution X-ray scattering is an extremely powerful tool for investigating the equilibrium and kinetics of cooperative conformational transitions of oligomeric protein complex, especially when combined with other spectroscopic techniques such as fluorescence spectroscopy.

High Resolution Near Infrared Spectrum of NGC 7023

  • Le, Huynh Anh N.;Pak, Soojong;Lee, Hye-In;Lee, Jae-Joon;Nguyen-Luong, Quang;Kaplan, Kyle;Jaffe, Daniel T.
    • 천문학회보
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    • 제39권2호
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    • pp.93.1-93.1
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    • 2014
  • The reflection nebula NGC 7023 is a typical example of a photodissociation region (PDR), which consists of high density molecular gas that is exposed to an intense UV radiation field. The source of the UV photons in NGC 7023 is the young pre-main-sequence Be star HD 200755. We present our near-infrared high-resolution (R ~ 40,000) spectrum of NGC 7023, covering a region of $1{\times}15$ arcseconds, observed during the commissioning runs of IGRINS (Immersion GRating near-INfrared Spectrometer). The spectrum shows many strong narrow emission lines that arise from the molecular rovibrational transitions of H2. From the intensity ratios between these H2 lines, we investigate physical conditions within the PDR such as the temperature, density, and pressure. The high spectral resolution of IGRINS allows us to resolve the velocity field of the PDR. In addition, we compare the IGRINS spectrum to Cloudy PDR model.

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Comprehensive Performance Analysis of Interconnect Variation by Double and Triple Patterning Lithography Processes

  • Kim, Youngmin;Lee, Jaemin;Ryu, Myunghwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제14권6호
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    • pp.824-831
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    • 2014
  • In this study, structural variations and overlay errors caused by multiple patterning lithography techniques to print narrow parallel metal interconnects are investigated. Resistance and capacitance parasitic of the six lines of parallel interconnects printed by double patterning lithography (DPL) and triple patterning lithography (TPL) are extracted from a field solver. Wide parameter variations both in DPL and TPL processes are analyzed to determine the impact on signal propagation. Simulations of 10% parameter variations in metal lines show delay variations up to 20% and 30% in DPL and TPL, respectively. Monte Carlo statistical analysis shows that the TPL process results in 21% larger standard variation in delay than the DPL process. Crosstalk simulations are conducted to analyze the dependency on the conditions of the neighboring wires. As expected, opposite signal transitions in the neighboring wires significantly degrade the speed of signal propagation, and the impact becomes larger in the C-worst metals patterned by the TPL process compared to those patterned by the DPL process. As a result, both DPL and TPL result in large variations in parasitic and delay. Therefore, an accurate understanding of variations in the interconnect parameters by multiple patterning lithography and adding proper margins in the circuit designs is necessary.

Design of A Compact Single-Balanced Mixer for UWB Applications

  • Mohyuddin, Wahab;Kim, In Bok;Choi, Hyun Chul;Kim, Kang Wook
    • Journal of electromagnetic engineering and science
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    • 제17권2호
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    • pp.65-70
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    • 2017
  • The design and implementation aspects of a new single-balanced mixer for ultra-wideband (UWB) applications are presented in this study. The proposed mixer utilizes a miniaturized UWB ring coupler as a balun, consisting of a pair of in-phase and inverted-phase transitional structures. The well-balanced UWB performance of the ring coupler, aside from the optimized diode matching, results in improved conversion loss and inter-port isolations for a wide bandwidth. The size of the implemented single-balanced diode mixer is reduced to about 60% of the area of the conventional single-balanced ring diode mixer. The measured results of the proposed mixer exhibit an average conversion loss of 7.5 dB (minimum 6.7 dB) and a port-to-port isolation of greater than 18 dB over a UWB frequency range of 3.1-10.6 GHz. The measured results agree well with the simulated results.

Local Electronic Structures of Graphene Probed by Scanning Tunneling Spectroscopy

  • Jang, Won-Jun;Lee, Eui-Sup;Kim, Howon;Yoon, JongKeon;Chang, Yunhee;Kim, Yong-Hyun;Kahng, Se-Jong
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.132.2-132.2
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    • 2013
  • Electrons in graphene make ballistic transport with very high mobility (${\sim}2{\times}105 $cm2V-1s-1), which holds promises for applications in fast electronic devices. However, such expectations have been hampered by the semi-metallicity or zero bandgap of graphene, which makes it impossible to completely turn off graphene transistor devices. Here, we report the observations of local bandgap modulations in Moir$\acute{e}$ patterned graphene on metal substrates using scanning tunneling microscopy and spectroscopy. The Moir$\acute{e}$ patterned graphene was made by combinations of self-assembly processes, and they showed additional electronic states that could be interpreted as sub-band states. Our experimental observations could be explained with orbital transitions of carbon atoms from sp2 to sp3, as supported by our density functional theory calculation results. Our findings will add new poweful components for device applications.

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Increasing the Range of Modulation Indices with the Polarities of Cells and Switching Constraint Reliefs for the Selective Harmonic Elimination Pulse Width Modulation Technique

  • Najjar, Mohammad;Iman-Eini, Hossein;Moeini, Amirhossein
    • Journal of Power Electronics
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    • 제17권4호
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    • pp.933-941
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    • 2017
  • In this paper an improved low frequency selective harmonic elimination-PWM (SHE-PWM) technique for Cascaded H-bridge (CHB) converters is proposed. The proposed method is able to eliminate low order harmonics from the output voltage of the converter for a wide range of modulation indices. To solve SHE-PWM equations, especially for low modulation indices, a modified method is used which employs either the positive or negative voltage polarities of H-bridge cells to increase the freedom degrees of each cell. Freedom degrees of the switching angles are also used to increase the range of available solutions for non-linear SHE equations. The proposed SHE methods can successfully eliminate up to $25^{th}$ harmonic from a 7-level output voltage by using just nine switching transitions or a 150 Hz switching frequency. To confirm the validity of the proposed method, simulation and experimental results have been presented.

대학생의 취업이행 과정의 어려움에 관한 잠재유형과 정신적 안녕감과의 관계 (An Association between the Latent Profiles of the Difficulties Associated with School- to-Work Transitions and Mental Well-Being among University Students)

  • 전지원
    • Human Ecology Research
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    • 제61권3호
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    • pp.335-348
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    • 2023
  • The purpose of this study was to identify: (a) the latent profiles of the difficulties associated with the schoolto-work transition (decline in confidence, mood swings, family disagreements, the burdens of familial expectations, economic hardship, and a lack of support) made by university students, (b) predictors (gender, age, grade, university location, co-residence with parents on weekdays, monthly household income, and parental educational attainment) of these profiles, and (c) how the profiles were associated with mental wellbeing. The participants of this study were 311 senior or above students (164 males and 147 females) under the age of 29, who were unmarried and preparing for employment. The findings of this study were as follows. First, the latent profile analysis revealed three distinct profiles: the "low overall difficulties" type (25.4%), the "moderate overall difficulties" type (49.9%), and the "high overall difficulties" type (24.7%). Second, the factors that predicted each profile included gender, age, co-residence with parents on weekdays, monthly household income, and parental educational attainment. Third, the "low overall difficulties" type demonstrated the highest level of mental well-being (emotional, social, and psychological well-being). This study was significant for examining the latent profiles of the difficulties associated with the school-to-work transition made by university students preparing for employment, while also exploring their mental well-being. Based on the results of this study, practical implications, limitations, and suggestions for further study were discussed.

YAlO3:Tbx3+에서 발광소멸 곡선을 이용한 에너지 전달에 관한 연구 (A Study on the Energy Transfer of YAlO3:Tbx3+ using Decay Curves)

  • 김광철;최진수
    • 반도체디스플레이기술학회지
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    • 제14권1호
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    • pp.13-17
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    • 2015
  • $YAlO_3:Tb{_x}^{3+}$ has been synthesized by a combustion process and the concentration x of Tb was varied from 0.001 and 0.05 mol% per mole of YAlO3. The energy transfer of $^5D_3{\rightarrow}^7F_6$(385nm) and $^5D_4{\rightarrow}^7F_5$(544nm) transitions on the $YAlO_3:Tb{_x}^{3+}$(x =0.001, 0.05) have been investigated by using decay curves. The energy transfer mechanism was explained by Inokuti and Hirayama model. The results of calculation and fitting showed that values of n are 6.11(x=0.01) and 6.13(x=0.005). These indicate that the energy transfer mechanism between $Tb^{3+}$ ions is dipole-dipole interaction.