• ALGAE
• /
• 제22권1호
• /
• pp.31-36
• /
• 2007

The gametophytic filaments of two genetically distinct taxa of Bangia from New Zealand showed unusual rhizoidal development in comparative culture experiments. In the past Bangia has been reported to possess simple, colourless rhizoids that extend from the basal cells of the unbranched filaments, whereas in this study the rhizoids observed became pigmented and multicellular. A reversal of growth direction occurred and filamentous extensions developed from the rhizoids under some culture conditions. These extensions were either prostrate or resembled new gametophytic filaments. This is the first report for filamentous members of the Bangiales of the development of such stolon-like rhizoids, apparently serving as a form of vegetative reproduction.

• Computers and Concrete
• /
• 제1권2호
• /
• pp.189-209
• /
• 2004

Several extensions to the Thelandersson phenomenological model for concrete under transient high temperatures are explored. These include novel expressions for the temperature degradation of the elastic modulus and the temperature dependency of the coefficient of the free thermal strain. Furthermore, a coefficient of thermo mechanical strain is proposed as a bi-linear function of temperature. Good qualitative agreement with various test results taken from the literature is demonstrated. Further extensions include the effects of plastic straining and temperature dependent Poisson's ratio. The models performance is illustrated on several simple benchmark problems under uniaxial and biaxial stress states.

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 2000년도 제1회 신소재 심포지엄(차세대 광소재 심포지엄)
• /
• pp.53-76
• /
• 2000

Multi-color organic electroluminescent (EL) displays have already been commercialized, and the simple extensions of present technologies on organic EL can not be a target for basic research anymore. Future prospect of research on organic electroluminescent devices are described from the view point of possible future break-through. Three aspects, perspective for further increase of device efficiencies, possibility of simplified device structures and possible use of thick organic layers, are discussed.

• 호남수학학술지
• /
• 제38권1호
• /
• pp.71-84
• /
• 2016

The aim of this work is to compute the volume of the graph polytope associated with various type of finite simple graphs composed of paths and stars. Recurrence relations are obtained using the recursive volume formula (RVF) which was introduced in Lee and Ju ([3]). We also discussed the relationship between the volume of the graph polytopes and the number of linear extensions of the associated posets for given bipartite graphs.

• 복식문화연구
• /
• 제23권1호
• /
• pp.102-116
• /
• 2015

This study aimed to identify the effects of fashion brand extensions types, preannouncing and consumers' regulatory focus on preference towards extension products. To that end, the study used a 2 (fashion brand extension types: similar vs. non-similar) ${\times}2$ (preannouncing: near preannouncing vs. far preannouncing) ${\times}2$ (regulatory focus: promotion focus vs. prevention focus) three mixed elements. The subjects of the study were 280 men and women in their 20~40s living in Seoul and Chungnam province and total of 229 data were analyzed. Data were analysed with SPSS 19.0 program and three-way ANOVA, simple interaction effects and simple main effects analysis were conducted. The results of this study are as follows: First there were significant differences in preference based on fashion brand extension types and preannouncing. Second, there were significant interaction effects in preference between extension types of fashion brand and regulatory focus. But there was no difference in preference toward extension products according to types of preannouncing and regulatory focus. Lastly, fashion brand extension types, preannouncing and regulatory focus showed significant interaction effects on preference. Thus even in cases of non-similar brand extensions which carry more risk of failing, the appropriate marketing communication strategies such as preannouncing will result in brand preference. Also marketing activities should be comprehensive and strategical based on consumers' tendencies in order to derive positive evaluations.

• PNF and Movement
• /
• 제15권3호
• /
• pp.381-387
• /
• 2017

Purpose: Although some studies indicate that the Sorensen test may not be used to examine back muscles such as the erector spinae, alternatives to the back-extension test are rarely suggested. Therefore, the purpose of the present study was to investigate an effective way to stimulate the erector spinae muscles by adding a component of trunk rotation and lateral bending to general back extensions. Methods: A total of 18 healthy, physically active participants performed simple trunk extension, extension with trunk rotation, and extension with lateral bending. Surface electromyography responses of the latissimus dorsi, thoracic, and lumbar levels of the erector spinae; the gluteus maximus; and the biceps femoris muscles were investigated during these 3 conditions of modified back extension tests. Results: The simple trunk extension exercise caused significant increases in activity of the gluteus maximus and biceps femoris muscles as compared to the extension with rotation and lateral bending exercises. The extension with trunk rotation exercise showed significantly greater activation in the thoracic and lumbar levels of the erector spinae and in the latissimus dorsi as compared to the other exercises. The index measuring subjective difficulty was significantly lower in the simple trunk extension exercise as compared to the extension with trunk rotation and extension with lateral bending exercises. Conclusion: The present study suggests that extension with trunk rotation has the advantage of stimulating the para-spinal muscles, while simple trunk extension may not be adequate to selectively simulate the para-spinal muscles but may be appropriate for examining global trunk extensors.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2005년도 추계종합학술대회
• /
• pp.951-954
• /
• 2005

인터넷 사용자들의 급증으로 인터넷을 이용한 다양한 부가서비스들이 창출되고 있으며 가장 대표적인 것이 인터넷 전화이다 최근들어 인스턴트 메시징 및 프레즌스 서비스의 응용서비스가 보편적으로 확대되고 있는 추세이며 이 서비스는 IETF의 IMPP 워킹 그룹에서 표준이 개발되고 있는데 IMPPP 워킹그룹에서는 인스턴트 메시징 및 프레즌스 서비스를 위한 기본 모델 및 요구사항, 공통데이터 포맷 등에 대한 표준을 담당하고 있다. 또한, 사용자의 친구 목록 관리 및 권한 부여 등 IMPP 서비스를 위한 확장은 SIMPLE 워킹그룹에서 정의하고 있다. 본 논문에서는 IETF SIMPLE(SIP for Instant Messaging and Presence Leveraging Extensions) 워킹그룸에 대한 표준 진행 사항과 IMPP 서비스에서 친구 목록 및 사용자의 권한 설정을 관리해주는 XCAP 서버 설계를 다룬다.

• Journal of applied mathematics & informatics
• /
• 제28권3_4호
• /
• pp.697-710
• /
• 2010

In this paper, we prove existence of infinitely many positive and concave solutions, by means of a simple approach, to $3^{th}$ order three-point singular boundary value problem {$x^{\prime\prime\prime}(t)=\alpha(t)f(t,x(t))$, 0 < t < 1, $x(0)=x'(\eta)=x^{\prime\prime}(1)=0$, (1/2 < $\eta$ < 1). Moreover with respect to multiplicity of solutions, we don't assume any monotonicity on the nonlinearity. We rely on a combination of the analysis of the corresponding vector field on the phase-space along with Knesser's type properties of the solutions funnel and the well-known Krasnosel'ski$\breve{i}$'s fixed point theorem. The later is applied on a new very simple cone K, just on the plane $R^2$. These extensions justify the efficiency of our new approach compared to the commonly used one, where the cone $K\;{\subset}\;C$ ([0, 1], $\mathbb{R}$) and the existence of a positive Green's function is a necessity.

• 대한수학회논문집
• /
• 제10권3호
• /
• pp.499-518
• /
• 1995

In this paper we consider more systematically the centralizer C(S) of the set $S = {f_a $\mid$ f_a : X \to X ; x \longmapsto x * a, a \in X}$ with respect to the semigroup End(X) of all endomorphisms of an implicative BCK-algebra X with the condition (S). We obtain a series of interesting results. The main results are stated as follows : (1) C(S) with repect to a binary operation * defined in a certain way forms a bounded implicative BCK-algebra with the condition (S). (2) X can be imbedded in C(S) such that X is an ideal of C(S)/ (3) If X is not bounded, it can be imbedded in a bounded subalgebra T of C(S) such that X is a maximal ideal of T. (4) If $X (\neq {0})$ is semisimple, C(S) is BCK-isomorphic to $\prod_{i \in I}{A_i}$ in which ${A_i}_{i \in I}$ is simple ideal family of X.

• Journal of Power Electronics
• /
• 제11권2호
• /
• pp.148-155
• /
• 2011

Direct torque control(DTC) of induction machines is known to offer fast instantaneous torque and flux control with a simple control structure. However, this scheme has two major disadvantageous, namely, a variable inverter switching frequency and a high torque ripple. These problems occur due to the use of hysteresis comparators in conventional DTC schemes, particularly in controlling the output torque. This paper reviews the utilization of constant frequency torque controllers (CFTC) in DTC to solve these problems while retaining the simple control structure of DTC. Some extensions of the work in utilizing a CFTC will be carried out in this paper which can further reduce the torque ripple. This is particularly useful for a system which has a limited/low sampling frequency. The feasibility of a CFTC with an extended carrier frequency in minimizing the torque ripple is verified through experimental results.