• Journal of Communications and Networks
• /
• 제12권2호
• /
• pp.150-157
• /
• 2010

Understanding and optimizing the energy consumption of wireless devices is critical to maximize the network lifetime and to provide guidelines for the design of new protocols and interfaces. In this work, we first provide an accurate analysis of the energy performance of an IEEE 802.11 WLAN, and then we derive the configuration to optimize it. We further analyze the impact of the energy configuration of the stations on the throughput performance, and we discuss under which circumstances throughput and energy efficiency can be both jointly maximized and where they constitute different challenges. Our findings are that, although an energy-optimized configuration typically yields gains in terms of throughput as compared against the default configuration, it comes with a reduction in performance as compared against the maximum-bandwidth configuration, a reduction that depends on the energy parameters of the wireless interface.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제41권5호
• /
• pp.273-277
• /
• 2015

Angiosarcoma is a rare and aggressive malignant tumor that has a poor prognosis. It represents less than 1% of all malignancies occurring in the oral cavity and salivary glands. We present a 35-year-old male with angiosarcoma of the cheek following traumatic injury and a review of the current literature.

• 한국수학교육학회지시리즈D:수학교육연구
• /
• 제20권1호
• /
• pp.1-9
• /
• 2016

An accurate evaluation of educational process is a promise for the progress of education, because evaluation provides a meticulous idea of what has actually been achieved as a result of education. However, for all its significance in the educational fields, there are not many discussions about evaluation in South Korea. We believe that in order to overcome this discrepancy, diverse evaluation theories along with a discussion about the merits or demerits or each theory should be introduced in South Korea. We propose that Eisner's educational evaluation model may suggest alternative ways of perceiving evaluation. Eisner's educational evaluation model, named educational connoisseurship and criticism, emerged as an approach to educational evaluation from the methods used in art and literary criticism.

• 천문학회보
• /
• 제42권1호
• /
• pp.31.3-31.3
• /
• 2017

The presence of a bar in disk galaxies indicates that galaxies reached their dynamical maturity, and secular evolution has started to play key roles in the evolution of disk galaxies. Numerical simulations predicted that as a barred galaxy evolves, the bar becomes longer by capturing its immediate neighbor disk stars. We test the hypothesis by exploring bar lengths and measuring the light deficit around the bar at various redshift. Supplementing already classified barred galaxies in later type disk galaxies ($$T{\geq_-}2$$, Sheth et al. 2008), we classify barred galaxies among earlier type disk galaxies (T<2) up to z~0.8 using F814W images from the Cosmic Evolution Survey (COSMOS). We estimate the length of bars analytically for ~400 galaxies, and find that there is a slight decrease in bar length with redshift. We also find that longer bars show more prominent light deficit around the bar and this trend is stronger for nearby galaxies. Our results are consistent with the predictions from numerical simulations, and imply that the bar induced secular evolution is already in place since z~0.8. 

• 대한관절경학회:학술대회논문집
• /
• 대한관절경학회 제21차 추계 학술대회
• /
• pp.93-98
• /
• 2009

족관절 고정술은 족관절에 발생한 심한 관절염(end-stage arthritis)에서 전통적으로 시행하던 술식으로 현재 사용되고 있는 인공 족관절 치환술이 발달되기 전까지는 gold standard 로 알려져 있었으며 현재에도 심한 족관절의 변형이나 파괴, 족관절 인공 관절의 실패시에 시행되고 있다. 1897년 Albert가 처음으로 족관절 고정술을 소개한 이후로 30여가지가 넘는 방법이 행해지고 있으나 개방적 관절 고정술의 단점인 수술 후 염증, 유합 지연, 연부조직의 손상에 의한 피부 괴사 등을 극복하고 유합물을 높이기 위해 다양한 내고정 및 외고정 장치를 사용하고 있다. 관절경 술식이 발달하면서 Schnider가 1983년 최초로 관절경을 이용한 족관절 고정술을 발표한 이후로 관절경하의 족관절 고정술은 개방적 족관절 고정술 보다 높은 유합율과 적은 수술 합병증으로 인해 관심의 대상이 되었지만 족관절의 변형이 심한 경우에는 시행하기 어려운 단점이 있는 것으로 알려져 왔다.

• 대한수학회논문집
• /
• 제31권3호
• /
• pp.495-505
• /
• 2016

Let $f:{\mathbb{R}}^3{\rightarrow}{\mathbb{R}}$. In this paper we prove the stability of functional inequalities ${\mid}f(ux+vy,uy-vx,zw)-f(x,y,z)f(u,v,w){\mid}{\leq}{\phi}(u,v,w)$ or ${\phi}(x,y,z)$, ${\mid}f(ux-vy,uy-vx,zw)-f(x,y,z)f(u,v,w){\mid}{\leq}{\phi}(u,v,w)$ or ${\phi}(x,y,z)$ for all $x,y,z,u,v,w{\in}{\mathbb{R}}$. Furthermore, we give refined descriptions of bounded functions satisfying the inequalities as in Albert and Baker [1].

• Journal of Microbiology and Biotechnology
• /
• 제16권2호
• /
• pp.212-218
• /
• 2006

Three out of fourteen Microcystis-dominant cyanobacterial blooms in Central India were found to be toxic to mice ($LD_{50}$ ranging from 35-450 mg bloom dry mass/kg body weight). The liver architecture of the treated mice showed characteristic symptoms of hepatotoxicity relative to the untreated controls, with increased enzyme activities of serum lactate dehydrogenase (LDH), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), and serum glutamate pyruvate transaminase (SGPT). RP-HPLC revealed the presence of microcystin-LR, microcystin-RR, and desmethyl microcystin-RR in the given region to maximum amounts of 390, 1,030, and $860{\mu}g/g$ bloom dry weight, respectively, corresponding to a maximum of 2.8 mg/l microcystin-LR in the lake water. Further confirmation of the microcystin variants was conducted using a MALDI-TOF MS analysis.

• Communications for Statistical Applications and Methods
• /
• 제20권6호
• /
• pp.455-466
• /
• 2013

In nested case-control studies, the most common way to make inference under a proportional hazards model is the conditional logistic approach of Thomas (1977). Inclusion probability methods are more efficient than the conditional logistic approach of Thomas; however, the epidemiology research community has not accepted the methods as a replacement of the Thomas' method. This paper promotes the inverse probability weighting method originally proposed by Samuelsen (1997) in combination with an approximate jackknife standard error that can be easily computed using existing software. Simulation studies demonstrate that this approach yields valid type 1 errors and greater powers than the conditional logistic approach in nested case-control designs across various sample sizes and magnitudes of the hazard ratios. A generalization of the method is also made to incorporate additional matching and the stratified Cox model. The proposed method is illustrated with data from a cohort of children with Wilm's tumor to study the association between histological signatures and relapses.

• Toxicological Research
• /
• 제31권2호
• /
• pp.137-149
• /
• 2015

Human hepatocytes, with complete hepatic metabolizing enzymes, transporters and cofactors, represent the gold standard for in vitro evaluation of drug metabolism, drug-drug interactions, and hepatotoxicity. Successful cryopreservation of human hepatocytes enables this experimental system to be used routinely. The use of human hepatocytes to evaluate two major adverse drug properties: drug-drug interactions and hepatotoxicity, are summarized in this review. The application of human hepatocytes in metabolism-based drug-drug interaction includes metabolite profiling, pathway identification, P450 inhibition, P450 induction, and uptake and efflux transporter inhibition. The application of human hepatocytes in toxicity evaluation includes in vitro hepatotoxicity and metabolism-based drug toxicity determination. A novel system, the Integrated Discrete Multiple Organ Co-culture (IdMOC) which allows the evaluation of nonhepatic toxicity in the presence of hepatic metabolism, is described.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2007년도 학술발표회 논문집
• /
• pp.58-66
• /
• 2007

This paper introduces the new generic dynamic neuro-fuzzy local modeling system (DNFLMS) that is based on a dynamic Takagi-Sugeno (TS) type fuzzy inference system for complex dynamic hydrological modeling tasks. The proposed DNFLMS applies a local generalization principle and an one-pass training procedure by using the evolving clustering method to create and update fuzzy local models dynamically and the extended Kalman filtering learning algorithm to optimize the parameters of the consequence part of fuzzy local models. The proposed DNFLMS is applied to develop the inference model to forecast the flow of Waikoropupu Springs, located in the Takaka Valley, South Island, New Zealand, and the influence of the operation of the 32 Megawatts Cobb hydropower station on springs flow. It is demonstrated that the proposed DNFLMS is superior in terms of model accuracy, model complexity, and computational efficiency when compared with a multi-layer perceptron trained with the back propagation learning algorithm and well-known adaptive neural-fuzzy inference system, both of which adopt global generalization.