• 제목/요약/키워드: K

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A Comparison of Item Characteristics and Test Information Between the K-MMSE~2:SV and K-MMSE

  • Jihyang Kim;Seungmin Jahng;SangYun Kim;Yeonwook Kang
    • 대한치매학회지
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    • 제23권3호
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    • pp.117-126
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    • 2024
  • Background and Purpose: The Korean-Mini Mental State Examination, 2nd edition (K-MMSE~2) was recently released. This study aimed to determine whether the K-MMSE~2: Standard Version (K-MMSE~2:SV) had the same test characteristics as the K-MMSE. Methods: A total of 1,514 healthy community-based participants aged 19 to 90 years were administered the K-MMSE~2:SV Blue Form along with the language items from the K-MMSE. The item and test characteristics and test information for the K-MMSE~2:SV and K-MMSE were compared using Item Response Theory analysis. Results: Item discriminations for the K-MMSE~2:SV and K-MMSE were above the moderate range for all items except Recall. Most of the items on the K-MMSE~2:SV and K-MMSE had item category difficulty in the very easy or easy range. The test information curve (TIC) showed that the K-MMSE~2:SV and K-MMSE provide almost the same amount of information (27.86 vs. 28.44), with both tests providing the most information at an ability level of -1.57. The generalizability (G) coefficient for the K-MMSE~2:SV and K-MMSE was 0.99. Conclusions: These results indicate that the K-MMSE~2:SV and K-MMSE are equally optimal tests for screening for mild cognitive impairment and early dementia. Given that the amount of test information provided by the two tests was almost identical, the shapes of the TICs were very similar, and the G coefficient was close to 1, we can conclude that the K-MMSE and K-MMSE~2:SV are equivalent tests.

플라이휠 중량(重量)이 디젤 기관(機關)의 진동(振動)에 미치는 영향(影響) (Effect of Flywheel Weight on the Vibration of Diesel Engine)

  • 명병수;김성래
    • 농업과학연구
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    • 제20권2호
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    • pp.167-180
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    • 1993
  • 우리나라의 동력경운기(動力耕耘機)에 탑재(搭載)된 6.0 및 7.5kW의 수냉식(水冷式) 4행정(行程) 디젤기관(機關)의 성능향상(性能向上), 중량경감(重量經減), 생산비(生産費) 절감(節減)을 도모하고, 기관(機關) 설계시(設計時) 고려(考慮)할 수 있는 기본자료(基本資料)를 얻기 위(爲)하여 동력경효기 탑재용(搭載用) 기관(機關)의 부품중(部品中) 플라이 휠의 중량(重量)만을 32.2, 29.7, 26.2, $24.2kg_f$ 등(等)의 4수준(水準)으로 감소(減少)시켜, 출력(出力), 토크, 연료(燃料) 소비율(消費率), Motoring loss, 진동량(振動量) 등(等)을 측정(測定) 분석(分析)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. O사(社)의 소프트웨어에 의한 설계(設計)로 7.5kW 기관(機關)의 플라이휠의 최적중량(最適重量)은 $23.7kg_f$이었으며, 생산업체(生産業體)의 설계기준(設計基準)을 고려(考慮)하였을 경우 플라이휠 최적중량(最適重量)은 $24.51kg_f$으로서 두 경우 모두 현재(現在)의 플라이휠 중량(重量) $32.2kg_f$보다는 적은 것으로 나타났다. 2. 플라이휠의 중량(重量)이 $32.2kg_f$일 때 6.0kW기관(機關)의 경우 정격출력(定格出力)은 7.43kW, 7.5kW 기관(機關)의 경우에는 7.85kW이었으며, 플라이휠 중량(重量)을 $24.2kg_f$으로 감소(減少)시켰을 때 6.0kW 기관(機關)은 7.70kW로 0.27kW의 정격출력(定格出力)이 증가(增加)되었고 7.5kW 기관(機關)은 7.85kW에서 8.25kW로 0.39kW의 정격출력(定格出力)이 증가(增加)되었다. 3. 플라이휠중량(重量)이 $32.2kg_f$에서 $24.2kg_f$으로 감소(減少)되었을 때 연료소비율(燃料消費率)은 6.0kW 기관(機關)의 경우 약(約) 4.0g/kW-h만큼 감소(減少)되었으며, 7.5kW기관(機關)에서는 약(約) 0.8g/kW-h가 감소(減少)되였다. 4. 플라이휠 중량(重量)이 $32.2kg_f$에서 $24.4kg_f$으로 감소(減少)시킴에 따라 진동량(振動量)은 6.0kW와 7.5kW 두 기관(機關) 모두 크게 증가(增加)하는 경향(傾向)이었다. 5. Motoring loss는 플라이휠 중량(重量)을 $32.2kg_f$에서 $24.2kg_f$으로 감소(減少) 시켰을경우 2200rpm에서 6.0kW 기관(機關)은 2.33kW에서 1.76kW로 감소(減少)하였고 7.5kW에서는 2.46kW에서 1.84kW로 감소(減少)하였다. 6. 기관(機關)의 기계효율(機械效率)은 플라이휠의 중량(重量)을 $32.2kg_f$에서 $24.4kg_f$으로 감소(減少)시켰을때 6.0kW 기관(機關)은 76.1%에서 76.8%로 0.7%가 7.5kW 기관(機關)은 76.68%에서 77.02%로 0.34%가 증가(增加)하였다.

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Photophysical and Photochemical Property of ATX-S10

  • Ito, Toshiaki;Okazaki, Shigetoshi;Kageyama, Kazumi;Hirohata, Toru;Kohno, Eiji;Hirano, Toru
    • Journal of Photoscience
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    • 제9권2호
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    • pp.527-529
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    • 2002
  • Photodynamic therapy (PDT) is a medical treatment using laser and photosensitizing drug taken up to destroy cancer cells. Singlet oxygen ($^1$0$_2$) generation is strongly related to this treatment. We have built a direct detection system monitoring feeble luminescence, in the near IR region, from $^1$0$_2$, We have comparatively studied the photophysical and photochemical properties in solution of a newly developed drug ATX-S10 and Photofrin already investigated clinically. We demonstrdted that ATX-S10 was capable of efficiently yielding $^1$0$_2$, which may lead to highly efficient PDT treatment. Successive laser excitation photobleached ATX -S10 readily in a dose-dependent manner. This result shows that ATX -S10 is useful in setting up suitable medical treatment conditions to minimize side effects.

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MINIMAL QUASI-F COVERS OF SOME EXTENSION

  • Kim, Chang Il;Jung, Kap Hun
    • 충청수학회지
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    • 제26권2호
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    • pp.427-433
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    • 2013
  • Observing that every Tychonoff space X has an extension $kX$ which is a weakly Lindel$\ddot{o}$f space and the minimal quasi-F cover $QF(kX)$ of $kX$ is a weakly Lindel$\ddot{o}$f, we show that ${\Phi}_{kX}:QF(kX){\rightarrow}kX$ is a $z^{\sharp}$-irreducible map and that $QF({\beta}X)=QF(kX)$. Using these, we prove that $QF(kX)=kQF(X)$ if and only if ${\Phi}^k_X:kQF(X){\rightarrow}kX$ is an onto map and ${\beta}QF(X)=(QF{\beta}X)$.

ON k-QUASI-CLASS A CONTRACTIONS

  • Jeon, In Ho;Kim, In Hyoun
    • Korean Journal of Mathematics
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    • 제22권1호
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    • pp.85-89
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    • 2014
  • A bounded linear Hilbert space operator T is said to be k-quasi-class A operator if it satisfy the operator inequality $T^{*k}{\mid}T^2{\mid}T^k{\geq}T^{*k}{\mid}T{\mid}^2T^k$ for a non-negative integer k. It is proved that if T is a k-quasi-class A contraction, then either T has a nontrivial invariant subspace or T is a proper contraction and the nonnegative operator $D=T^{*k}({\mid}T^2{\mid}-{\mid}T{\mid}^2)T^k$ is strongly stable.

Multichannel SQUID Systems for Magnetocardiogram

  • Lee, Y.H.;Kim, J.M.;Kim, K.;Kwon, H.;Yu, K.K.;Kang, C,S.;Lee, S.K.;Lim, C.M.;Kim, I.S.;Park, Y.K.
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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    • pp.9-9
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    • 2006
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비타민 K와 골 건강 (Vitamin K and Bone Health)

  • 임상동;김기성
    • Journal of Dairy Science and Biotechnology
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    • 제29권1호
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    • pp.33-39
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    • 2011
  • Vitamin K, which is a nutritional factor, play a role in the regulation of bone metabolism. Vitamin K exists naturally in 2 forms, namely, vitamin $K_1$ (phylloquinone) in green plants and vitamin $K_2$ (menaquinone) in animals and bacteria. Vitamin $K_1$ has an effect on bone metabolism. Vitamin $K_2$ is essential for the ${\gamma}$-carboxylation of osteocalcin, a bone matrix protein containing ${\gamma}$-carboxyglutamic acid (Gla) which is synthesized in osteoblast of bone tissues. This paper is to provide the basic information of vitamin K by supplying function and biological activity of vitamin K together with vitamin K producing lactic acid bacteria and it's utilization for the dairy products production.

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자연에너지를 이용한 소수력 출력증대 방안 연구 (A Study on Output Increase of Small Hypro Power using Nature Energy)

  • 채지석;윤이수;김태호;김영일;마범구;최장규
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.1129-1130
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    • 2011
  • The output of small hydro power plant was generated less than rated output under high temperature. We Installed the artificial ventilation that blow cold wind from water supply pipe tunnel to small hydro power plant. The temperature of small hydro power has been decreased. The output of small hydro power plant has been increased from 405kW to 445kW.

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