• Title/Summary/Keyword: Constant frequency

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The Effect of Enhancer on the Penetration of Indapamide through Hairless Mouse Skin (경피흡수촉진제의 영향에 따른 인다파마이드의 피부투과)

  • Seo, Hui;Jeung, Sang-Young;Park, Ji-Seon;Shin, Byung-Cheol;Hwang, Sung-Joo;Cho, Sun-Hang
    • Journal of Pharmaceutical Investigation
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    • v.37 no.4
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    • pp.237-242
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    • 2007
  • The chemical formula of indapamide is 3-(aminosulfonyl)-4-chloro-N-(2,3-dihydro-2-methyl-1H-indol-l-yl)-benzamide, Indapamide is an oral antipertensive diuretic agent indicated for the treatment of hypertensive and edema. Indapamide inhibits carbonic anhydrase enzyme. Transdermal drug delivery systems, as compared to their corresponding classical oral or injectable dosage form counterparts, offer many advantages. The most important advantages are improved systemic bioavailability of the pharmaceutical active ingredients (PAI), because the first-pass metabolism by the liver and digestive system are avoided; and the controlled, constant drug delivery profile (that is, controlled zero-order absorption). Also of importance is the reduced dose frequency compared to the conventional oral dosage forms (that is, once-a-day, twice-a-week or once-a-week). Other benefits include longer duration of therapeutic action from a single application, and reversible action. For example, patches can be removed to reverse any adverse effects that may be caused by overdosing. In order to evaluate the effects of vehicles and penetration enhancers on skin permeation of Indapamide, the skin permeation rates of Indapamide from vehicles of different composition were determined using Franz cells fitted with excised hairless skins. Solubility of Indapamide in various solvents was investigated to select a vehicle suitable for the percutaneous absorption of Indapamide, The solvents used were Tween80, Tween20, Labrasol, Lauroglycol90 (LG90) and Peceol. Lauroglycol90 increase the permeability of indapamide approximately 3.75-fold compared with the control. Tween80, Tween20, Labrasol, Lauroglycol90 (LG90) and Peceol showed flux of $0.06ug/cm^2/hr,\;0.4ug/cm^2/hr,\;0.21ug/cm^2/hr,\;0.72ug/cm^2/hr,\;0.29ug/cm^2/hr$, respectively.

Effect of Starvation on the Total Metabolism of Crangon affinis (자주새우, Crangon affinis의 총대사에 미치는 기아의 영향)

  • CHIN Pyung;SHIN Yun-Kyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.5
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    • pp.371-382
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    • 1992
  • Biochemical composition, the rates of nitrogen excretion in the form of ammonia, amino acids and total nitrogen, and oxygen consumption of the shrimp Crangon affinis were measured at three temperature regimes $(7,\;15,\;and\;25^{\circ}C)$ and the variations were also determined for starvation periods (1-25 days). The composition of the major biochemical fractions was analysed into carbohydrate: $4.2\%,\;protein:\;68.6\%,\;lipid:\;7.0\%,\;chitin:\;6.3\%,\;and\;ash:\;14.6\%,$ all expressed as percentage of dry weight. Molting frequency was lower at $7^{\circ}C\;than\;25^{\circ}C$ during the period of starvation, and during the same period the higher temperature was, body weight and body compositions the more decreased. Through all starvation periods $O_2$ consumption tended to decrease but total nitrogen tended to increase at any temperature regimes. The dominant form of excreted total nitrogen was ammonia-N at any temperature. From the O:N ratio it appeared that carbohydrate and lipid reserves were quickly exhausted (1-5 days), and that proteins were the substrates oxidized to meet the energetic requirements of C. affinis at any temperature. After 25 days of starvation the O:N ratio remained constant near a value of 8, which indicates that only proteins were being utilized at three temperatures. After 25 days of starvaion C. affinis excreted 23.01ug N/mg body nitrogen per day at $7^{\circ}C,\;32.97\mu g\;N/mg$ body nitrogen per day at $15^{\circ}C,\;and\;44.81\mu g\;N/mg$ body nitrogen per day at $25^{\circ}C$, and lost about 1.75, 2.47 and $3.29^{\circ}C$ of body protein per day at 7, 15, and $25^{\circ}C$ respectively.

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Differences on Satisfaction of Healthcare Applications by Smartphone Users' Characteristics (스마트폰 사용자 특성에 따른 헬스케어 애플리케이션 만족도 차이)

  • Shim, Hun;Kim, Yu-Jeong;Park, Mijeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.7
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    • pp.410-419
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    • 2016
  • This study examined the satisfaction difference in the aspects of awareness, information quality, and availability in healthcare applications according to smartphone user's characteristics. Data collection was conducted between September 17th and September 21st 2014 on the 193 people who had used healthcare applications, and the data collected were analyzed with descriptive statistics, t-test, One-way ANOVA, and Kruskal-Wallis test using SPSS WIN 20.0. Differences in satisfaction of healthcare application were observed according to the general characteristics, and according to age, education level, and income, as well as for healthcare application use characteristics, according to operation system, total use period, the number of installed healthcare applications, the sources of main information, use frequency, and reasons of no use. To establish strategies for the effective spread of mobile healthcare and development and distribution of healthcare applications, it will be necessary to confirm smartphone users' characteristics and it is important to reflect them in the strategies. In addition, it is necessary to develop and implement a range of strategies to ceaselessly induce the users' motives of use and to improve their degree of satisfaction to secure the constant use of developed health care applications.

The analysis for emotion stability though music - In prioirty of relieve the adolescent's aggression from smartphone overuse (음악의 정서안정 효과에 대한 분석 -청소년기 스마트 폰 과다 사용으로 인한 공격적 성향 완화를 중심으로)

  • Kim, Kwan-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.237-244
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    • 2017
  • This study examined the pathological phenomenon of smartphone addiction and prevention. The smartphone provides many conveniences but it also brings psychological and physical problems, such as failure of learning capacity, maladjustment, and impulsive actions. To provide actual proof, this material included correlation analysis among physical, verbal aggression and smartphone addiction factors through high school students. Using SPSSWIN 22.0, frequency analysis, mail factor analysis, T-test, correlation analysis, regression analysis were also included. The main factors of smartphone addiction discrimination were divided into 'aim for imaginary', 'daily obstacles', 'tolerance', 'withdrawal symptom'. Smartphone addicted group members show the result of r=0.668 (physical aggression), r=0.704 (verbal aggression), r=0.481 (hostility). (p< 0.001). This study focused on the aggression from smartphone overuse and the positive effect of music for adolescent's mind stability. Moreover, suggestions for constant research on the pathological phenomena from smartphone addiction and prevention programs are made.

Microwave Dielectric Properties in Bi-Substituted BaO.$Nd_{2}O_{3}$.$4TiO_{2}$ (Bi 가 치환된 BaO.$Nd_{2}O_{3}$.$4TiO_{2}$ 세라믹스의 마이트로파 유전특성)

  • Cheon, Jae-Il;Kim, Jeong-SeoG
    • Korean Journal of Materials Research
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    • v.8 no.7
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    • pp.659-663
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    • 1998
  • The effect of Bi-substitution in $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ ceramic was studied on the formation of crystal phases, microstructure, and microwave dielectric properties. $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$, solid solution (0$\leq$x$\leq$0.2) were formed by Bi-substitution into the Nd site of $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ ceramics. Average grain size increased with Bi-substitution. Dielectric constant(${\varepsilon}_r$) increased from 84 to U8, and the temperature coefficient of resonant frequency(${\tau}_f$) decreased from 44 ppm/$^{\circ}C$ to -30 ppm/$^{\circ}C$ when Bi contents increased up to x=0.2 in $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ solid solutions. $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ solid solutions with x=0.04~0.08 showed the most superior microwave dielectric properties, those are ${\varepsilon}_r$= 89-92, Q . f = 5855~6091 GHz, and (${\tau}_f$)= -7.5-7.5 ppm/$^{\circ}C$.

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Refinement of damage identification capability of neural network techniques in application to a suspension bridge

  • Wang, J.Y.;Ni, Y.Q.
    • Structural Monitoring and Maintenance
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    • v.2 no.1
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    • pp.77-93
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    • 2015
  • The idea of using measured dynamic characteristics for damage detection is attractive because it allows for a global evaluation of the structural health and condition. However, vibration-based damage detection for complex structures such as long-span cable-supported bridges still remains a challenge. As a suspension or cable-stayed bridge involves in general thousands of structural components, the conventional damage detection methods based on model updating and/or parameter identification might result in ill-conditioning and non-uniqueness in the solution of inverse problems. Alternatively, methods that utilize, to the utmost extent, information from forward problems and avoid direct solution to inverse problems would be more suitable for vibration-based damage detection of long-span cable-supported bridges. The auto-associative neural network (ANN) technique and the probabilistic neural network (PNN) technique, that both eschew inverse problems, have been proposed for identifying and locating damage in suspension and cable-stayed bridges. Without the help of a structural model, ANNs with appropriate configuration can be trained using only the measured modal frequencies from healthy structure under varying environmental conditions, and a new set of modal frequency data acquired from an unknown state of the structure is then fed into the trained ANNs for damage presence identification. With the help of a structural model, PNNs can be configured using the relative changes of modal frequencies before and after damage by assuming damage at different locations, and then the measured modal frequencies from the structure can be presented to locate the damage. However, such formulated ANNs and PNNs may still be incompetent to identify damage occurring at the deck members of a cable-supported bridge because of very low modal sensitivity to the damage. The present study endeavors to enhance the damage identification capability of ANNs and PNNs when being applied for identification of damage incurred at deck members. Effort is first made to construct combined modal parameters which are synthesized from measured modal frequencies and modal shape components to train ANNs for damage alarming. With the purpose of improving identification accuracy, effort is then made to configure PNNs for damage localization by adapting the smoothing parameter in the Bayesian classifier to different values for different pattern classes. The performance of the ANNs with their input being modal frequencies and the combined modal parameters respectively and the PNNs with constant and adaptive smoothing parameters respectively is evaluated through simulation studies of identifying damage inflicted on different deck members of the double-deck suspension Tsing Ma Bridge.

Low Temperature Sintering and Microwave Dielectric Properties of Zn1-x(Li1/2La1/2)xTiO3 Ceramics (Zn1-x(Li1/2La1/2)xTiOM3계 세라믹스의 저온 소결 및 마이크로파 유전특성)

  • 김응수;한기문
    • Journal of the Korean Ceramic Society
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    • v.41 no.2
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    • pp.165-169
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    • 2004
  • Microwave dielectric properties and the behavior of low-temperature sintering of $Zn_{1-x}(Li_{1/2}La_{1/2})_xTiO_3$ ($0.01{\leq}x{\leq}0.05$) with 4 wt% $H_3BO_3$ were investigated as a function of $(Li_{1/2}La_{1/2})^{2+}$ content. The sintering temperature of the specimens can be reduced from $1150^{\circ}C$ to $875^{\circ}C$ with the addition of 4 wt% $H_3BO_3$ as a sintering agent. Dielectric constant (K) and Temperature Coefficient of resonant Frequency (TCF) with the substitution of ($(Li_{1/2}La_{1/2})^{2+}$ ion depended on dielectric mixing rule. Quality factor (Qf) depended on density and microstructure. Typically, K of 26.5, Qf of 19,030 GHz and TCF of 7.5 ppm$/^{\circ}C$ were obtained for the specimens with x=0.03 sintered at $875^{\circ}C$ for 3 h.

The Langmuir Adsorption Isotherms of the Electroadsorbed Hydrogens at the Single Crystal Pt(100)/Aqueous Electrolyte Interfaces (단결정 Pt(100)/수용액 계면에서 전가흡착된 수소의 Langmuir흡착등온식)

  • Chun Jang Ho;Jeon Sang Kyoo
    • Journal of the Korean Electrochemical Society
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    • v.4 no.1
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    • pp.14-20
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    • 2001
  • The Langmuir adsorption isotherms of the under-potentially deposited hydrogen (UPD H) and the over-potentially deposited hydrogen (OPD H) at the single crystal Pt(100)/0.5 M $H_2SO_4$ and 0.5 M LiOH aqueous electrolyte interfaces have been studied using the phase-shift method. The phase-shift profile $({-\varphi}\;vs.\;E)$ for the optimum intermediate frequency can be used as a useful method to estimate the Langmuir adsorption isotherm $(\theta\;vs.\;E)$ at the interfaces. The equilibrium constant (K) for the OPD H and the standard free energy $({\Delta}G_{ads})$ of the OPD H at the Pt(100)/0.5M $H_2SO_4$ aqueous electrolyte interface are $1.5\times10^{-4}$ and 21.8 kJ/mol, respectively. At the Pt(100)/0.5 LiOH aqueous electrolyte interface, K transits from 1.9(UPD H) to $6.8\times10^{-6}$(OPD H) depending on the cathode potential (E) and vice versa. Similarly, ${\Delta}G_{ads}$ transits -1.6 kJ/mol (UPD H) to 29.5 kJ/mol (OPD H) depending on E and vice versa. The transition of K and ${\Delta}G_{ads}$ is attributed to the two distinct adsorption sites of the UPD H and OPD H on the Pt(100) surface. The UPD H and the OPD H at the Pt(100) interfaces are the independent processes depending on the H adsorption sites rather than the sequential processes for the cathodic $H_2$ evolution reactions.

A Study on the Key Factors Affecting Travel Time Budget for Elderly Pedestrians (고령자 통행시간예산의 영향요인 규명에 관한 연구)

  • Choi, Sung-taek;Kim, Su-jae;Jang, Jin-young;Lee, Hyang-sook;Choo, Sang-ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.14 no.4
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    • pp.62-72
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    • 2015
  • Nowadays the issue of aging society has received considerable critical attention, especially in transportation planning and demand forecasting. This study identified the factors related to travel time budget for elderly by purpose using seemingly unrelated regression model (SUR model). The SUR model is suitable when error terms of each equation are assumed to be correlated across the equations in terms of travel time budget which is constant in 2 hours per day commonly. The results showed that elderly's travel time budget was affected by individual, household, urban facility and transportation service. The leisure travel comprised a large proportion of total travel time and had a positive relationship with elderly, sports, religious facilities. Moreover, the elderly who had low income or unemployed person had low frequency of social activity such as leisure, shopping and business. This study can provide a comprehensive implications of forecasting the future travel demand and analyzing the travel behavior.

A temperature stable bandpass filter using dieletric-filled stepped impedance resonators (접합된 Stepped impedance resonator를 이용한 온도보상형 유전체 대역통과 필터)

  • Lim, Sang-Kyu;Kim, Jun-Chul;Kim, Duck-Hwan;Ha, Jong-Su;Oh, Chang-Heon;Sim, Hwa-Sup;An, Chul
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.2
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    • pp.78-85
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    • 1998
  • The design method of a temperature stable bandpass filter using dielectric coaxial resonators of with two dielectric ceramics with opposite signs of temperature coefficient of dielectric constant (${\tau}_{\epsilon}$) to compensate for each other in this method. $MgTiO_3$(${\tau}_{\epsilon}$=+99 ppm/${\circ}C$) as a positive ${\tau}_{\epsilon}$ material and Ba($Zn_{1/3}Nb_{2/3}$)$O_3$(${\tau}_{\epsilon}$=-77ppm/${\circ}C$) as a negative material were selected. The length of a SIR for the temperature stability was calculated according to the design method and the susceptance slope parameter of the SIR was obtained. A temperature stable bandpass filter using dielectric SIR's was designed, simulated and fabricated. The center frequency of this filter was 915 MHz and the pass bandwidth was 20 MHz. Temperature properties of this bandpass filter by simulations were compared with the measured results of the bandpass filter fabricated.

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