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Cardiovascular Disease-related Health Beliefs and Lifestyle Issues Among Karen Refugees Resettled in the United States From the Thai-Myanmar (Burma) Border

  • Kamimura, Akiko;Sin, Kai;Pye, Mu;Meng, Hsien-Wen
    • Journal of Preventive Medicine and Public Health
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    • v.50 no.6
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    • pp.386-392
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    • 2017
  • Objectives: Refugees resettled in the US may be at risk for cardiovascular disease (CVD). However, little is known about CVD-related issues among Karen refugees who have migrated to the US from the Thai-Myanmar border. The purpose of this study was to examine CVD-related health beliefs and lifestyle issues among Karen refugees resettled in the US. Methods: Karen refugees resettled in the US from the Thai-Myanmar border (n=195) participated in a survey study on health beliefs related to CVD, salt intake, physical activity (PA), and smoking in the fall of 2016. Results: A high-salt diet, physical inactivity, and smoking were major lifestyle problems. Participants who adhered to a low-salt diet considered themselves to be susceptible to CVD. Most participants did not engage in regular PA. Regular PA was associated with less perceived susceptibility to CVD and greater perceived benefits of a healthy lifestyle for decreasing the likelihood of CVD. Conclusions: Each refugee population may require individualized strategies to promote PA and a healthy diet. Future studies should develop health education programs that are specifically designed for Karen refugees and evaluate such programs. In addition to health education programs on healthy lifestyle choices, tobacco cessation programs seem to be necessary for Karen refugees. At the same time, it is important to foster strategies to increase the utilization of preventive care among this population by promoting free or reduced-fee resources in the community to further promote their health.

Analysis of the electrical characteristics of the novel TIGBT with additional pMOS (새로운 구조의 pMOS 삽입형 TIGBT의 전기적 특성 분석)

  • Lee, Hyun-Duck;Won, Jong-Il;Yang, Yil-Suk;Koo, Yong-Seo
    • Journal of IKEEE
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    • v.14 no.1
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    • pp.55-64
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    • 2010
  • In this paper, we proposed the novel TIGBT with an additional p-type MOS structure to achieve the improved trade-off between turn-off and on-state voltage drop(Vce(sat)). These low on-resistance and the fast switching characteristics of the proposed TIGBT are caused by an enhanced electron current injection efficiency which is caused by additional p-type MOS structure. In the simulation result, the proposed TIGBT has the lower on state voltage of 1.67V and the shorter turn-off time of 3.1us than those of the conventional TIGBT(2.25V, 3.4us).

고전압 펄스 시스템 '천둥'을 이용한 $N_2$, $SF_6$ 혼합기체에서의 전기 스위칭 연구

  • Byeon, Yong-Seong;Song, Gi-Baek;Park, Ji-Hun;Eom, Hwan-Seop;Ryu, Han-Yong;Choe, Eun-Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.503-503
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    • 2012
  • 본 연구에서는 최대전압 600 KV, 최대전류 88 KA, 펄스 폭 60 ns의 특성을 가지는 고전압 펄스 시스템 '천둥'을 이용하여 방전 챔버에 고전압 펄스를 인가하고 $N_2$$SF_6$ 혼합기체 종류와 여러 가지 기체압력에서 전기 트리거를 이용한 방전현상을 전기, 광학적으로 연구하였다. 전극은 구리텅스텐 합금재질의 표준전극을 사용하였고, 전극 간격은 10 mm로 고정하였다. 방전 챔버 압력을 100 torr, 1기압, 2 기압에서 실험을 진행하였고, $N_2$에 대한 $SF_6$의 혼합비율을 0~100%까지 변화시키며 실험을 진행하였다. 전기 트리거 신호가 인가된 펄스 방전 스위치의 방전전압 및 방전 기작원리, 트리거 스위칭 지연시간, 트리거 절연파괴 기작원리, 그리고 이때 생성된 플라스마의 전자 온도 및 밀도에 관한 전기광학 특성 등에 관한 기초연구를 수행하였다. 트리거 펄스가 있을 때의 방전개시전압은 트리거 지연시간 20 us 에서 최소가 되는 특성을 보이며, 이때의 SF6 함량에 따른 최소방전전압과 트리거 펄스가 없을 때의 방전전압을 서로 비교하였다. 이를 통하여 A-K gap 10 mm 조건에서 20 us의 트리거 펄스의 지연시간을 가지는 방전 개시전압은 트리거 펄스가 없을 때 전극 간격이 6 mm에 해당되는 방전개시 전압 값을 가짐을 실험적으로 보였다. 이는 트리거 펄스에 의하여 전극 주위에 쉬스가 형성되며, 이로 인한 전극 간격이 가까워지며, 이와 같은 효과 때문에 방전개시전압은 그만큼 낮아지는 것으로 해석 할 수 있다.

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CONVOLUTION SUMS OF ODD AND EVEN DIVISOR FUNCTIONS

  • Kim, Daeyeoul
    • Honam Mathematical Journal
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    • v.35 no.3
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    • pp.445-506
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    • 2013
  • Let ${\sigma}_s(N)$ denote the sum of the s-th power of the positive divisors of N and ${\sigma}_{s,r}(N;m)={\sum_{d{\mid}N\\d{\equiv}r\;mod\;m}}\;d^s$ with $N,m,r,s,d{\in}\mathbb{Z}$, $d,s$ > 0 and $r{\geq}0$. In a celebrated paper [33], Ramanuja proved $\sum_{k=1}^{N-1}{\sigma}_1(k){\sigma}_1(N-k)=\frac{5}{12}{\sigma}_3(N)+\frac{1}{12}{\sigma}_1(N)-\frac{6}{12}N{\sigma}_1(N)$ using elementary arguments. The coefficients' relation in this identity ($\frac{5}{12}+\frac{1}{12}-\frac{6}{12}=0$) motivated us to write this article. In this article, we found the convolution sums $\sum_{k<N/m}{\sigma}_{1,i}(dk;2){\sigma}_{1,j}(N-mk;2)$ for odd and even divisor functions with $i,j=0,1$, $m=1,2,4$, and $d{\mid}m$. If N is an odd positive integer, $i,j=0,1$, $m=1,2,4$, $s=0,1,2$, and $d{\mid}m{\mid}2^s$, then there exist $u,a,b,c{\in}\mathbb{Z}$ satisfying $\sum_{k& lt;2^sN/m}{\sigma}_{1,i}(dk;2){\sigma}_{1,j}(2^sN-mk;2)=\frac{1}{u}[a{\sigma}_3(N)+bN{\sigma}_1(N)+c{\sigma}_1(N)]$ with $a+b+c=0$ and ($u,a,b,c$) = 1(Theorem 1.1). We also give an elementary problem (O) and solve special cases of them in (O) (Corollary 3.27).

Homoepitaxial Growth on GaN Substrate Grown by HVPE (HVPE법에 의해 성장된 GaN 기판의 Homoepitaxial 성장)

  • Kim, Chong-Don;Kim, Young-Soo;Ko, Jung-Eun;Kwon, So-Young;Lee, Sung-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.14-14
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    • 2006
  • Homoepitaxial growth of GaN on n-type GaN substrates was carried out by hydride vapor phase epitaxy (HVPE) method. This enables us to reduce or to eliminate the bowing of the GaN substrate caused by thermal mismatch. As a result, the two opposite crystal surfaces have been found to possess low dislocation density. The surface polarity of the homoepitaxially grown GaN was confirmed by both etching of the surface and conversion beam electron diffraction(CBED). The surface morphology and the photoluminescencemeasurement indicated that the surface properties of N-polar face of the homoepitaxlally grown GaN are quite different from the initial N-polar face of the heteroepitaxially grown GaN substrate Also, both surfaces of the GaN substrate were characterized by room temperature Double crystal X-ray diffraction (DCXRD) and photoluminescence measurement.

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The Gettering Effect of Boron Doped n-type Monocrystalline Silicon Wafer by In-situ Wet and Dry Oxidation

  • Jo, Yeong-Jun;Yun, Ji-Su;Jang, Hyo-Sik
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.429-429
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    • 2012
  • To investigate the gettering effect of B-doped n-type monocrystalline silicon wafer, we made the p-n junction by diffusing boron into n-type monocrystalline Si substrate and then oxidized the boron doped n-type monocrystalline silicon wafer by in-situ wet and dry oxidation. After oxidation, the minority carrier lifetime was measured by using microwave photoconductance and the sheet resistance by 4-point probe, respectively. The junction depth was analyzed by Secondary Ion Mass Spectrometry (SIMS). Boron diffusion reduced the metal impurities in the bulk of silicon wafer and increased the minority carrier lifetime. In the case of wet oxidation, the sheet resistance value of ${\sim}46{\Omega}/{\Box}$ was obtained at $900^{\circ}C$, depostion time 50 min, and drive-in time 10 min. Uniformity was ~7% at $925^{\circ}C$, deposition time 30 min, and drive-in time 10 min. Finally, the minority carrier lifetime was shown to be increased from $3.3{\mu}s$ for bare wafer to $21.6{\mu}s$ for $900^{\circ}C$, deposition 40 min, and drive-in 10 min condition. In the case of dry oxidation, for the condition of 50 min deposition, 10 min drive-in, and O2 flow of 2000 SCCM, the minority carrier lifetime of 16.3us, the sheet resistance of ${\sim}48{\Omega}/{\Box}$, and uniformity of 2% were measured.

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New Randomness Testing Methods using Approximate Periods (근사 주기를 이용한 새로운 랜덤성 테스트 기법)

  • Lim, Ji-Hyuk;Lee, Sun-Ho;Kim, Dong-Kyue
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.6
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    • pp.742-746
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    • 2010
  • In this paper, we propose new randomness testing methods based on approximate periods in order to improve the previous randomness testing method using exact pattern matching. Finding approximate periods of random sequences enables us to search similarly repeated parts, but it has disadvantages since it takes long time. In this paper we propose randomness testing methods whose time complexity is O($n^2$) by reducing the time complexity of computing approximate periods from O($n^3$) to O($n^2$). Moreover, we perform some experiments to compare pseudo random number generated by AES cryptographic algorithms and true random number.

A study on the flume for a current meter rating (유속계 검정용수로에 관한 연구)

  • 정준석;박정응
    • Water for future
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    • v.6 no.2
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    • pp.30-37
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    • 1973
  • The coefficient of the current meter generally determined by the maker Its coefficient is subject to being changed with time. Therefore the coefficient of the current meter has to be checked up before it is ready to be used Such an inspection is termed a current meter rating The current meter equipped an electronic apparatus and all the others are to be rated in a rating flume. The price current meter which is most widely used for measuring flow velocities ranging between 0.3m/sec and 3.5m/sec has been used in this study. The length of the flume and the optimum range of the rating in the cross section are determined in the range of 20∼120cm deep, 50∼160cm wide of the flume. In this study, the 23 different kinds of the current meter rating enabled us to determine the constants a and b of the following equation. V=an+b(m/sec) where, n is number of revolution per second(n=N/T) V is velocity(v=D/T) The above constant can be determined by the least squares method and plotting, using the velocity(V=D/T) and the number of revolution per second(n=N/T) obtained from the running distance(D), time(T), the number of revolutin(N), and the running number(m). From the experiments the following conclusions are drawn: 1) The rating flume is large enough if the flume is 110∼120cm deep, and 40∼50m long. 2) The optimum depth for rating of a current meter is in the range of h=40∼50cm.

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THE RANDER CHANGES OF FINSLER SPACES WITH ($\alpha,\beta$)-METRICS OF DOUGLAS TYPE

  • Park, Hong-Suh;Lee, Il-Yong
    • Journal of the Korean Mathematical Society
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    • v.38 no.3
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    • pp.503-521
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    • 2001
  • A change of Finsler metric L(x,y)longrightarrowL(x,y) is called a Randers change of L, if L(x,y) = L(x,y) +$\rho$(x,y), where $\rho$(x,y) = $\rho$(sub)i(x)y(sup)i is a 1-form on a smooth manifold M(sup)n. Let us consider the special Randers change of Finsler metric LlongrightarrowL = L + $\beta$ by $\beta$. On the basis of this special Randers change, the purpose of the present paper is devoted to studying the conditions for Finsler space F(sup)n which are transformed by a special Randers change of Finsler spaces F(sup)n with ($\alpha$,$\beta$)-metrics of Douglas type to be also of Douglas type, and vice versa.

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Enhanced Backpropagation : Algorithm and Numeric Examples (개선된 역전파법 : 알고리즘과 수치예제)

  • Han Hong-Su;Choi Sang-Ung;Jeong Hyeon-Sik;No Jeong-Gu
    • Management & Information Systems Review
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    • v.2
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    • pp.75-93
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    • 1998
  • In this paper, we propose a new algorithm(N_BP) to be capable of overcoming limitations of the traditional backpropagation(O_BP). The N_BP is based on the method of conjugate gradients and calculates learning parameters through the line search which may be characterized by order statistics and golden section. Experimental results showed that the N_BP was definitely superior to the O_BP with and without a stochastic term in terms of accuracy and rate of convergence and might surmount the problem of local minima. Furthermore, they confirmed us that the stagnant phenomenon of learning in the O_BP resulted from the limitations of its algorithm in itself and that unessential approaches would never cured it of this phenomenon.

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