The Consumption pattern of Milk Products and The Development of New Dairy Products in Japan

Sukegawa, Kinjiro Korean Society of Milk Science and Biotechnology 1983 Journal of Dairy Science and Biotechnology (JMSB) Vol.2 No.2

일본의 유제품 소비형태와 신유제품의 발달

SUKEGAWA, Kinjiro 한국축산학회 1979 한국축산학회지 Vol.21 No.7

기능성 식품(機能性 食品)으로서의 우유(牛乳)

祐川今次郞 ( Sukegawa Kinjiro ) 한국유가공기술과학회 1996 Journal of Dairy Science and Biotechnology (JMSB) Vol.14 No.2

Improvement of Bias Voltage Dependence in Lattice-Matched MgAl₂O₄-Basedmagnetictunneljunctions

Hiroaki Sukegawa,Huixin Xiu,Tadakatsu Ohkubo,Tomohiko Niizeki,Shinya Kasai,Takao Furubayashi 한국자기학회 2010 한국자기학회 학술연구발표회 논문개요집 Vol.2010 No.12

The Actual Conditions of FTA Utilization and Improvement Measures of Japanese Firms in ASEAN

스케가와 세이야(Seiya Sukegawa),이점순(Jum soon Lee) 중앙대학교 한국전자무역연구소 2018 전자무역연구 Vol.16 No.3

연구목적: 본 연구에서는 1993년 이후 ASEAN의 FTA 추진 동향과 일본기업들의 對아세안 FTA의 활용실태 및 문제점에 대해 살펴보았다. 특히 ASEAN+1 FTA의 자유화 수준과 원산지규정 등의 측면에서 ASEAN+1형태의 FTA 활용상의 과제를 제시하고자 하였다. 논문구성/논리: 제2장에서는 일본기업들의 FTA 활용과 관련된 선행연구를 개관한다. 제3장에서는 일본기업의 對아세안 FTA 활용실태를 파악하고, 제4장에서는 각 FTA별로 상이한 자유화의 수준, 원산지규정 등이 존재하는 상황에서 일본기업들의 FTA 활용상의 과제를 검토하고자 한다. 마지막으로 제5장에서는 본 연구의 내용을 요약 정리한다. 결과: 본 연구결과, 일본기업들의 對아세안 FTA에서의 부품조달·공급네트워크의 대부분이 ASEAN이 구축해 온 FTA 적용범위 내에서 이뤄지고 있으며, FTA 활용률도 점차 높아지고 있다. 한편 각 FTA별로 자유화 수준과 원산지규정, HS코드 버전 등이 서로 달라 FTA 간의 유기적 연계를 어렵게 하고 있는 것으로 나타났다. 독창성/가치: 일반적으로 FTA망을 구축·확대하는 과정에서 현지 조달과 역내조달이 촉진되는 것으로 생각되어져 왔다. 그러나 본 연구에서는 FTA 활용 촉진을 목표로 한 원산지규정의 완화가 오히려 현지조달 및 역내 조달 수준을 감소시키는 것으로 나타났다. Purpose: This study examines the trends of ASEAN s FTA since 1993 and the situation and problems of using ASEAN FTA with Japanese companies. In particular, the ASEAN + 1 FTA is discussed in terms of its liberalization level and rules of origin. Composition/Logic: Section II outlines previous studies on the use of FTAs by Japanese companies. In Section Ⅲ we examine the actual use of ASEAN FTAs by Japanese companies, and in Section Ⅳ, we examine the companies’ challenges in terms of different liberalization levels and rules of origin for each FTA. Finally, Section Ⅴ summarizes the contents of this study. Findings: Results of this study show that most parts of the procurement and supply networks of Japanese companies in ASEAN FTA are within the scope of FTAs established by ASEAN, and the FTA utilization rate is gradually increasing. On the other hand, the level of liberalization, origin regulation, and HS (tariff number) version are different for each FTA, making it difficult to organically link FTAs. Originality/Value: In general, it has been thought that local and intra-regional procurement are promoted in the process of establishing and expanding FTA networks. However, this study showed that a relaxation of the rules of origin with the aim of promoting the use of FTAs could instead reduce local procurement as well as procurement levels in the region.

Investigation of ramped voltage stress to screen defective magnetic tunnel junctions

Choi, Chulmin,Sukegawa, Hiroaki,Mitani, Seiji,Song, Yunheub IOP 2018 Semiconductor science and technology Vol.33 No.1

<P>A ramped voltage stress (RVS) method to screen defective magnetic tunnel junctions (MTJs) is investigated in order to improve screen accuracy and shorten test time. Approximately 1500 MTJs with 1.25 nm thick tunnel barriers were fabricated for this evaluation, and normal MTJs show a 189% tunnel magnetoresistance ratio, a 365 Ω <I>μ</I>m<SUP>2</SUP> resistance-area product, and a 1.8 V breakdown voltage, which is enough for applying reliable screen tests. We successfully classified MTJs as normal MTJs having good characteristics or defective MTJs having insufficient endurance and showing resistance degradation after only short-term cycling. Using the RVS screen test with low ramp speed, it is demonstrated that remarkable screening performance and little dependence on temperature are obtained for short test time.</P>

Reliability of magnetic tunnel junctions with a spinel MgAl₂O₄ film

Choi, C.M.,Sukegawa, H.,Mitani, S.,Song, Y.H. IET 2017 Electronics letters Vol.53 No.2

<P>We investigated the stress-induced resistance drift and breakdown characteristics in MgAl2O4 (MAO)-based magnetic tunnel junctions (MTJs) with the MAO thickness of similar to 0.9 nm. The occurrence of trap sites around the tunnel barrier-electrode interfaces was characterised via interval voltage stress (IVS) and constant voltage stress (CVS) experiments, in which the occurrence of trap sites affects the resistance drift in IVS and time- dependent dielectric breakdown in CVS. The observed resistance drift ratios were almost the same for positive and negative applied voltages, indicating that the difference in the interface structure was negligibly small between the top and bottom MAO/CoFe interfaces in the MAO-based MTJs. More interestingly, the resistance drift ratios were very low compared with the results of a previous study on MgO-based MTJs. MAO- based MTJs is likely to be an effective alternative that can be used to improve MTJ device reliability.</P>

TDDB modeling depending on interfacial conditions in magnetic tunnel junctions

Choi, Chul-Min,Sukegawa, Hiroaki,Mitani, Seiji,Song, Yun-Heub IOP 2017 Semiconductor science and technology Vol.32 No.10

<P>We investigated time-dependent dielectric breakdown (TDDB) modeling for MgO dielectrics with/without Mg insertion of MgO-based magnetic tunnel junctions (MTJs). The number of permanent trap sites at the no-Mg insertion interface was much larger than that at the Mg-inserted interface as determined by interval voltage stress (IVS) tests. The interfacial conditions related to trap sites at MgO dielectrics give rise to the different TDDB modeling. Here, we confirmed that the TDDB curves obtained from the constant voltage stress (CVS) tests for the Mg inserted interface case were well fitted by the power-law voltage V model, while the case of no-Mg inserted interface showed a good correlation to the 1/E model. The difference in the TDDB models related to interfacial conditions was understood based on theoretical and experimental results. Finally, we concluded that it is necessary to select an appropriate reliability model depending upon the presence or absence of the trap sites at dielectric interfaces.</P>

Effect of Mg insertion on time-dependent dielectric breakdown in MgO-based magnetic tunnel junctions

Choi, C.M.,Sukegawa, H.,Mitani, S.,Song, Y.H. IET 2016 Electronics letters Vol.52 No.12

<P>The stress-induced breakdown characteristics in magnesium oxide (MgO)-based magnetic tunnel junctions (MTJs) including an inserted Mg layer 0.5 nm thick is investigated, above or below an MgO tunnel barrier. Regardless of the insertion position, the inserted layer suppressed the time-dependent dielectric breakdown (TDDB) observed in the case of electron tunnelling into the Mg-inserted interface. This indicates that the Mg insertion significantly suppressed trap site formation at the anode-side barrier/electrode interface. The improvement of TDDB by the Mg insertion was confirmed through constant voltage stress experiments. Therefore, interface modification by means of inserting an ultra-thin metallic layer is highly effective in improving the reliability of an MTJ tunnel barrier for practical applications.</P>

Design of MgAl₂O₄ Spinel-Oxide-Based Tunnel Barriers for Advanced Spintronics Devices

Kenji Nawa,Keisuke Masuda,Shinto Ichikawa,Hiroaki Sukegawa,Tsuyoshi Suzuki,Katsuyuki Nakada,Seiji Mitani,Yoshio Miura 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.2

Tunnel magnetoresistance (TMR) in magnetic tunnel junctions (MTJs) is one of the central properties to develop high-performance spintronics devices. MgO(001) with bcc-Fe or CoFe electrodes has been mostly studied as a tunnel barrier of MTJs for the last decades because of its giant TMR ratio originating from the spin-filtering effect of Δ₁-symmetric evanescent states (s, pz, d3z²-r² orbitals), as predicted in 2001. However, the TMR ratio of MgO-MTJs reduces significantly by bias voltage applications, indicating a limitation of the output voltage of the MTJ. Recent experiments show that the use of a (001)-oriented spinel-type oxide, MgAl₂O₄, as a tunnel barrier improves the robustness of the TMR ratio under bias applications, but a theoretical TMR limit in Fe/MgAl₂O₄/Fe(001) MTJs is very small compared to the MgO-MTJs. This is because the in-plane lattice periodicity of Fe electrode is half of that of MgAl₂O₄ and a band-folding effect is induced in the two-dimensional Brillouin zone of the in-plane wave vector in the Fe electrode. This effect provides additional conductive states at the Δ line in MgAl₂O₄-MTJ, contributing to the reduction of the TMR ratio. In this talk, we propose a combined trilayer tunnel barrier, MgO/MgAl₂O₄/MgO, to overcome the above issue of the small TMR limit of MgAl₂O₄-MTJs on the basis of the first-principles calculations. We performed ballistic-conductance calculations in an Fe/MgO(n)/MgAl₂O₄/MgO(n)/Fe(001) MTJ using the non-equilibrium Green’s functions method to clarify the TMR ratio under bias voltage application. Here, number of MgO layers (n-ML) is changed as n = 1, 2, 3. In the case of n = 1, a large TMR ratio of 1184% is obtained at a zero-bias voltage and this large value is almost maintained up to V = 1.2 V (see blue in Fig. 1), leading to a large voltage output. In contrast, a single barrier MgAl₂O₄ shows only a small TMR ratio (~125%), which is constant below V = 1.6 V (see orange in Fig. 1). These results indicate that both the models have a similar tendency in bias voltage dependence of TMR, except for the magnitude of a TMR ratio. Moreover, we clarified that the presence of an MgO interlayer between Fe and MgAl₂O₄ plays an important role in retaining (blocking) the Δ1 evanescent state for majority (minority) spin. The former leads to the robustness of the TMR ratio against bias voltage as observed in single MgAl₂O₄ MTJs, while the latter does to the large TMR ratio as in single MgO MTJs. 〈그림 본문참조〉