• Journal of KIISE:Computing Practices and Letters
• /
• v.5 no.2
• /
• pp.247-262
• /
• 1999

이동 컴퓨팅 환경의 특징은 대역폭의 제약과 잦은 접속의 단절이다. 앞으로 이동 컴퓨팅에 대한 요구는 증가할 것이며 이동 컴퓨팅 환경을 극복할 수 있고 동적으로 적응할 수 있는 서비스를 필요로 한다. RPC(Remote Procedure Call)는 동기적이며 믈록(block)상태를 유발시키는 통신 구조로 분산 응용 프로그램을 작성하기 위한 환경을 제공한다. M-RPC(Mobile RPC) 는 RPC를 이동 컴퓨팅 환경에 맞도록 확장한 것이다. MOM(Message Oriented Middleware)은 분산 통신을 위한 미들웨어로서 분산 프로세스들간에 동기적 또는 비동기적 상호 작용을 지원하는 peer-to-peer 분산 컴퓨팅 모형으로 특징지워진다. 본 논문은 기존 MOM 시스템을 기반으로 하여 이동 컴퓨팅 환경을 지원하는 M-MOM(Mobile-MOM) 시스템을 제안하고 자바 언어로 구현하여 성능을 평가한다. M-MOM 환경에서 이동 호스트(mobile host)에서 실행되는 응용 프로그램과 고정 호스트(fixed host)에서 실행되는 메시지 큐 관리자는 베이스 스테이션(Base Station)에서 실행되는 메시지 에이전트를 통해 메시지 큐 관리자와 동적으로 연결된다. 비동기적인 서비스를 지원하는 M-MOM은 동기적인 서비스만을 지원하는 M-RPC 보다 이동 컴퓨팅 환경을 보다 효과적으로 극복할 수 있는 서비스를 지원한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10d
• /
• pp.64-66
• /
• 2002

HLA(High Level Architecture)를 기반으로 한 시뮬레이션들은 분산 환경에서 수행되는 특징을 갖는다. 이러한 시뮬레이션들은 지난 몇 년 동안 계속해서 그 규모가 커지고, 복잡해지고 있다. 이런 분산 시뮬레이션을 실행시킬 때 페더레이트(federate)들의 오동작으로 네트워크의 혼잡을 유발하는 등의 문제점이 생길 수 있다. 이러한 문제점을 효율적으로 해결하기 위해서는 이와 같은 분산 시뮬레이션을 관리 할 수 있는 수단이 필요하게 되었다. HLA 개발자들은 페더레이션(federation)의 내부를 알기 위해서 객체 모델을 개발했고, 이것을 Management Object Model(MOM) 이라고 한다. HLA MOM은 페더레이션을 모니터링과 컨트롤하며 관리 할 수 있게 한다. HLA RTI는 페더레이트간에 효율적으로 정보를 교환하게 하는 분산 운영 시스템이며 MOM을 통해서 RTI의 운영정보에 접근하고, 수행을 통제 할 수 있는 방법을 제공하고 있다. MOM을 이용할 경우 RTI 운영 정보들은 기존의 RTI 서비스를 이용해서 전달될 수 있으며, 이런 특성으로 인해 시스템 관리를 목적으로 하는 어플리케이션을 용이하게 구현 할 수 있다. 따라서 본 논문에서는 HLA MOM을 이용한 페더레이션을 관리 하는 FMS(federation Management System)을 개발하고자 한다.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.14 no.6
• /
• pp.1081-1090
• /
• 2011

High Level Architecture(HLA) is a specification for interoperation among heterogeneous simulators which are executed in a distributed environment. HLA originally allows a number of federates to join in a federation using a single RTI(Run-Time Infrastructure). To interoperate federations without modifying RTI, agent federate, which represents behavior of a federation, can be used. Agent federate can use MOM(Management Object Model) service or agent-user protocol to acquire information of a federation. This paper performs various experiments to measure performance of two architectures. MOM service shows a loss of performance but can be applied without modifying user federates. Experiment results can be used to determine appropriate architecture for interoperation of federations.

• Journal of Soil and Groundwater Environment
• /
• v.17 no.4
• /
• pp.73-80
• /
• 2012

The objectives of this research were to study the applicability and limitations of permeable reactive barrier (PRB) for the removal of tetrachloroethylene (PCE) from the groundwater. PRB column tests were conducted using reactive material with Moringa Oleifera Mass - Bentonite (Mom-Bentonite). Most of the PCE in the groundwater was degraded and/or captured (sorpted) in the zone containing activated material (MOM-Bentonite). The removal rate of PCE from the groundwater was 90% and 75% after 30 days and 180 days, respectively. The effect of micro-organisms on the long-term permeability and reactivity of the barrier is not well understood. MOM-Bentonite PRB system in this research has the potential to be developed into an environmentally and economically acceptable technology for the in situ remediation of PCE-contaminated groundwater.

• Ocean and Polar Research
• /
• v.25 no.3
• /
• pp.287-302
• /
• 2003

The seasonal variations in the circulation of the water mass in the East Sea/Japan Sea have been simulated using a free surface primitive ocean model, RIAMOM (RIAM Ocean Model), comparing the results from GFDL-MOM1 (Geophysical Fluid Dynamics Laboratory Modular Ocean Model, version 1.1, hereafter MOM) with the GDEM (Generalized Digital Environmental Model) data. Both models appear to successfully reproduce the distinct features of circulation in the East Sea/Japan Sea, such as the NB (Nearshore Branch) flowing along the Japanese coast, the EKWC (East Korean Warm Current) flowing northward along the Korean coast, and the NKCC/LCC (North Korean Cold Current/Liman Cold Current) flowing southwestward along Korean/Russian coast. RIAMOM has shown better performance, compared to MOM, in terms of the realistic simulation of the flow field in the East Sea/Japan Sea; RIAMOM has produced more rectified flows on the coastal region, for example, the narrower and stronger NKCC/LCC than MOM has. There is however obvious differences between the model results and the GDEM data in terms of the calculation of the water mass; both models have shown a tendency to overpredict temperature and underpredict salinity below 50m; more diffusive forms of thermocline and halocline have been simulated than noted in GDEM data.

• Journal of the Korean Society of Food Culture
• /
• v.33 no.3
• /
• pp.236-242
• /
• 2018

The purpose of this study was to evaluate the nutritional knowledge and dietary behaviors of middle school students according to their mother's employment status. Of all 453 subjects, 52.1% were boys, and 67.5% of the mothers were employed. The total score of nutritional knowledge was 8.0 out of 10 for students with a non-working mom and 7.7 for those with a working mom, showing no significant difference. Among the 20 nutritional knowledge questions, correct answer rates for "lots of fruits may be eaten because of not gaining weight" (72.6% vs. 81.6%, p<0.05) and "eating raw carrots is better than eating fried ones with oil" (34.6% vs. 44.9%, p<0.05) were significantly higher in students with a working mom. The regularity of meals showed a significant difference according to the mother's employment, indicating that responses of "very regular" (62.4% vs. 72.1%) were high among students with a non-working mom and responses of "skipping breakfast" (31.4% vs. 19.7%) were higher in students with a working mom (p<0.05). The number of snacks a day was also significantly different according to the mother's employment, showing that 12.8% of the students with a working mom and only 3.4% of them with a non-working mom did not eat snacks at all (p<0.05). These results reveal no significant difference in middle school students' nutritional knowledge according to their mother's employment status; however, the students whose mother had a job were more likely to have more undesirable dietary behaviors such as irregular meals and snacking.

• Korean Architects
• /
• s.658
• /
• pp.112-114
• /
• 2024

• Geophysics and Geophysical Exploration
• /
• v.11 no.2
• /
• pp.85-92
• /
• 2008

Magnetotelluric (MT) methods are widely applied as an effective exploration technique to geothermal surveys. Two-dimensional (2-D) analysis is frequently used to investigate a complicated subsurface structure in a geothermal region. A 2-D finite-element method (FEM) is usually applied to the MT analysis, but we must pay attention to the accuracy of so-called auxiliary fields. Rodi (1976) proposed an algorithm of improving the accuracy of auxiliary fields, and named it as the MOM method. Because it introduces zeros into the diagonal elements of coefficient matrix of the FEM total equation, a pivoting procedure applied to the symmetrical band matrix makes the numerical solution far less efficient. The MOM method was devised mainly for the inversion analysis, in which partial derivatives of both electric and magnetic fields with respect to model parameters are required. In the case of forward modeling, however, we do not have to resort to the MOM method; there is no need of modifying the coefficient matrix, and the auxiliary fields can be elicited from the regular FEM solution. The computational efficiency of the MOM method, however, can be greatly improved through a sophisticated rearrangement of the total equation.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.2687-2692
• /
• 2003

Recent advancement in information technology requires new interpretations for the space among human, machines and environment. Investigation of space between information and human could lead to the proper ways, in which human and machines meet. Various concepts regarding space have been explored in terms of “virtual reality in cyberspace” and “embodiment in tangible space.” “Mom (embodiment),” space, virtuality, sensation/perception, and interactive technology are some of the key ideas to be explored. Human “Mom” is such a fundamental membrane through which human can interact with the environment physically and mentally. An embodied interaction paradigm, based on “Mom,” is investigated. This leads to interactive technology paradigm. Sound space is an invisible but a tangible space in a sense that it travels in emotional tremors and stimulates new sensations and perceptions. Three cases are introduced to experiment such tangible space as a new and proper interactive paradigm. Also, a historical model of interaction is reviewed, which includes electrical, symbolic, textual, graphical, tangible, and social interaction.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.503-506
• /
• 2003

The most profound technologies are those that disappear. Silicon-based information technology, in contrast, is far from having become part of the environment. The idea of integrating computers seamlessly into the world at large runs counter to a number of present-day trends. Ubiquitous computing is not just aiming nomad multimedia. Rather, this computing environment lets us free to use computers without thinking and so to focus beyond them on new goals. In that context, Mom is such a fundamental membrane through which humans can interact with the environment. An embodied interaction paradigm, based on Mom, is investigated. Mom, space. sensing/perception, ubiquitous computing, and interactive technology are some of the key ideas to explore.