• Proceedings of the Korea Concrete Institute Conference
• /
• 2003.11a
• /
• pp.659-662
• /
• 2003

Recently, the floor thickness in residence may not be satisfied with the floor vibration criteria although the thickness is evaluated by the serviceability requirements in current design provisions. Thus it is necessary to develop the procedure to determine slab thickness satisfied with the floor vibration criteria. In this study, We proposed the methods to determine the slab thickness satisfied with the vertical floor vibration criteria for several concrete compressive strength of flat plate floor systems. For this purpose Monte Carlo simulation procedure was adopted and both randomness inherent in young modulus of concrete and heel drop intensity were accounted.

• Journal of the Korean Solar Energy Society
• /
• v.27 no.3
• /
• pp.79-85
• /
• 2007

This paper addresses the indoor air quality when radiant floor heating is applied in large space. Radiant heat exchange between surfaces depends on the orientation and the temperature of the surfaces. Also, the temperature and the radiant characteristic of the wall and the roof that face the floor have great influence on the indoor air environment due to the largeness of the wall and the roof in large spaces. In this study, we simulate a test-cell(25X20X10) using a ies YE And using a CFD(microflo in VE), an indoor air environment was investigated to establish the optimum temperature of floor. At the first time of the heating, high floor temperature is demanded. At the middle of the heating, however, the temperature of the residential space was formed appropriately, although the temperature of the floor was set low.

• Journal of Environmental Impact Assessment
• /
• v.14 no.4
• /
• pp.217-225
• /
• 2005

In apartment buildings, floor-impact sound has bean regarded as the major source which induces complaints from residents. It is mainly due to the use of light-weight structures. The vibration produced by impact on one part of an apartment building would travel as far as the other parts of structure with a little alleviation. As a result, the impact sound from upstairs has been regarded as a main source of noise causing discontentment among occupants. This study was carried out to measure the floor-impact sound levels and evaluate the insulation performance of floor-impact sound for nine apartment buildings. The floor-impact sound levels were measured for twenty-five On-dol floor structures and various factors which influence the floor-impact sound were analyzed.

• KIEAE Journal
• /
• v.7 no.2
• /
• pp.71-76
• /
• 2007

For the many years the children's running noise has caused perpetual frictions between neighbors in apartment houses. For this reason the government established a regulation to reduce the floor impact noise, as a result almost all apartment houses have been enforced to use the floor structure with 210mm thickness concrete slab and 120mm thickness of floor heating system since July 2005. If do not want to apply this kind of system, a system which obtain the certification from the institution appointed by government must be applied. In this reason a lot of construction material companies and construction companies have been trying to develop the system with 180mm thickness concrete slab for the purpose of reducing the cost. To develop the optimized floor system, actual size test building were constructed and the materials related with reducing floor impact noise were composited and tested in the test building. Through this procedure the most effective system was found.

• Journal of Mechanical Science and Technology
• /
• v.15 no.5
• /
• pp.544-554
• /
• 2001

A shop floor can be considered as an important level to develop Computer Integrated Manufacturing system (CIMs). However, a shop floor is a dynamic environment where unexpected events continuously occur, and impose changes to the planned activities. To deal with this problem, a shop floor should adopt an appropriate control system that is responsible for the coordination and control of the manufacturing physical flow and information flow. In this paper, a hybrid control system is described with a shop floor activity methodology called Multi-Layered Task Initiation Diagram (MTD). The architecture of the control model contains three levels: i.e., he shop floor controller (SFC), the intelligent agent controller (IAC) and the equipment controller (EC). The methodology behind the development of the control system is an intelligent multi-agent paradigm that enables the shop floor control system to be an independent, an autonomous, and distributed system, and to achieve an adaptability to change of the manufacturing environment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.11a
• /
• pp.1459-1462
• /
• 2007

In this study, vibration characteristics of concrete slab were investigated through FEM analysis. Four different floor plans with the floor area of $100{\sim}130m^2$ were chosen to be analyzed. Boundary conditions of two dimensional finite element models were determined based on the modal test results. Results showed that mode shapes were formed somewhat different according to the floor plan and the contribution of 1st mode on the floor vibration is generally the highest. Through the transient analysis, it was also found that floor plan, expecially connection of the living room with the kitchen, affected the vibration acceleration levels.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.8
• /
• pp.193-200
• /
• 2001

Recently, the concrete floor finishing robot, which can be used for flattening and smoothing the concrete floor, has been developed in Korea and Japan. While the previous research assumes that the concrete floor is deformable and the trowel is rigid in modeling the concrete floor finisher, we assume that the concrete floor is rigid and the trowel is deformable. Based on this assumption, we derived the equations of motion and found the convergent velocity of the concrete floor finisher using the computer simulation. From these results, we can understand the relationship between the motion characteristics and the design and control parameter of the robot.

• Asian-Australasian Journal of Animal Sciences
• /
• v.11 no.3
• /
• pp.234-238
• /
• 1998

Two experiments were conducted with broiler chickens to determine cage floor preferences, the strength of preference for a particular floor type and to evaluate the effect of rearing broilers on the preferred cage floor on productivity. In experiment 1, chicks when offered free access to either wire (WF) or plastic (PF) mesh flooring, preferred the former. However, when the perferred floor type (WF) was illuminated at 800 lux, birds spent longer time on PF. Also provision of incandescent lamps at PF resulted in broilers spending significantly longer period on WF. In experiment 2, while floor type had no effect on growth of female chicks throughout the duration of study, male chicks grown on PF were heavier than their WF counterparts on Days 21, 28, 35 and 42. Neither livability, nor incidence of breast blisters and leg deformities was affected by floor type.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.844-847
• /
• 2008

As customer's demands are varying, the type of floor plan of apartment is changed into expanded type with balcony unified to living room from general type with balcony separated from living room and so is changing the layout of L(living room), D(dining room) and K(kitchen). This study aims to examine how the type of floor plan of living room affects the floor impact sound insulation performance and to propose fundamental idea to floor plan layout of apartment in terms of floor impact sound reduction.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2005.03a
• /
• pp.228-235
• /
• 2005

The floor impact sound insulations are installed frequently for reducing the floor impact sound into the floor slab of the residential buildings in recent years. Therefore the analytical FE model considering the insulations is needed for the sound and vibration analysis of the floor and it is necessary to use a refined finite element model for considering the large number of modes involving in the dynamic responses. So it is very difficult to use FE model because of the tiresome task for constructing the FE model, taking a lot of times for analysis and the impossibility of using the proportional damping. The efficient analysis and modeling method are proposed to the dynamic analysis for the floor with floor impact sound insulations in this study. The floor slabs and finished layers are modeled individually and the spring elements that mean floor impact sound insulations use to connect two parts. The dynamic analysis by the $Newmark-{\beta}$ method is performed to solve the non-proportional damping problem due to the damping coefficient of insulations .