• Korea Real Estate Review
• /
• v.28 no.1
• /
• pp.39-52
• /
• 2018

The purpose of this study was to analyze the housing tenure choice decisions of older households, with focus on the activity constraints of the householders. For analysis, the probit model based on the data of the householders over 55 years of age from the 2015 KLIPS data was implemented. The research findings indicate that the ownership choice probability decreases when the head of the household has activity or social activity constraints. If there is an activity restriction, it is considered that the possibility of self-residence will be low due to the increase in medical expenses, the possibility of participation in economic activities will be low, the possibility of early retirement will be high, and the income will decrease. Therefore, if the head of the household has a personal or social activity constraint, such case is more likely to be categorized as falling under the poor residential group. This result suggests that the activity constraint can be utilized as a useful index for the housing welfare policy considering physical vulnerability.

• Journal of Family Relations
• /
• v.21 no.2
• /
• pp.77-96
• /
• 2016

Objectives: The aims of this study are to examine the associations between marital satisfaction and life satisfaction among Korean retirees in later life and to test whether the degrees of associations increased over time. Method: Nationally representative Korean Longitudinal Study of Ageing data from wave 1 (in 2006) to wave 4 (in 2012) was utilized and retirees in later life (65-89 years old, N=402) were analyzed. Latent growth modeling (LGM) and model constraint were applied using Mplus 7.3. Age, sex, household income, subjective health, depressive symptoms and elapsed time after retirement were included as control variables. Results: Linear unconditional LGM fitted the data well and showed gradual decrease in life satisfaction. Conditional LGM revealed significant associations between marital satisfaction and life satisfaction from time 1 to time 4. According to model constraint test, the size of associations between marital satisfaction and life satisfaction did not change with time. Conclusions: To sum up these results, the associations between marital satisfaction and life satisfaction were significant and relatively stable over time among retirees in later life. This study suggests one's spouse is a fundamental component of social convoy among Korean retirees in later life. Therefore, intervention programs targeted toward enhancing marital relationships among retirees' couples will help them to live a better life.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.20 no.3
• /
• pp.113-120
• /
• 2010

Content security and privacy protection are important issues in emerging network-based video surveillance applications. Especially, satisfying both real-time constraint and energy efficiency with embedded system-based video sensors is challenging since the battery-operated sensors need to compress and protect video content in real-time. In this paper, we propose a multicore-based solution to compress and protect video surveillance data, and evaluate the effectiveness of the solution in terms of both real-time constraint and energy efficiency. Based on the experimental results with MPEG2/AES software, we confirm that the multicore-based solution can improve the energy efficiency of a singlecore-based solution by a factor of 30 under the real-time constraint.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2000.11a
• /
• pp.463-470
• /
• 2000

In this paper, we describe a wireless MAC protocol named APRMA(Abitrary Period Reservation Multiple Access), which is capable of supporting the ABR type data service and maximizing channel utilization. In original PRMA protocol, data terminals with random data packets cannot reserve slot. That is, slot reservation is applicable to the. time constraint voice packet exclusively. But the reservation scheme have to be performed for loss sensitive data packet, so data packets can get their quality of service. The aspects of service, if fixed bandwidth is allocated to data terminals, time constraint voice packets may have a low efficiency So in this study, the terminal which wants to request for ABR type service, acquires a minimum bandwidth from system for the first time. If the system have extra available bandwidth, ABR terminals would acquire additional bandwidth slot by slot. As a result, APRMA protocol can support the data service with loss sensitivity and maintain their channel utilization highly. Also high Priority services like voice can be satisfied with their QoS by APRMA.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.9
• /
• pp.1851-1857
• /
• 2009

In this paper, reuse module generation algorithm consider the power consumption for FPGA technology mapping is proposed. To proposed algorithm is RT library generating algorithm consider power consumption for reuse module using FPGA technology mapping. In the first, selected FPGA for power consumption calculation. Technology mapping process have minimum total power consumption consider LUT's constraint in selected FPGA. A circuit into device by selected proper modules of allocation result for power consumption constraint using data.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.35D no.8
• /
• pp.76-81
• /
• 1998

This paper presents a new method to synthesize a digital hologram that meets the resolution of a currently manufactured LCD while capable of displaying a 3-D object. That is accomplished by segmenting a hologram, resulting in relaxed sampling constraint. We show that the segmentation of a hologram enables us to utilize the planewave approximation and, unlike in a holographic stereogram, it does not require projection process, but directly takes fourier transform of horizontally sliced 2-D images that constitute a 3-D object, which makes it possible to reconstruct a higher resolution image with depth information. We also show that proposed hologram contains data significantly smaller than the conventional hologram does, which is quite useful for constructing wide-viewing hologram. Finally, simulation results obtained by both methods are compared.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.2 s.95
• /
• pp.176-182
• /
• 1999

This paper presents a new autonomous kinematic calibration technique by using a laser-vision sensor called "Perceptron TriCam Contour". Because the sensor measures by capturing the image of a projected laser line on the surface of the object, we set up a long, straight line of a very fine string inside the robot workspace, and then allow the sensor mounted on a robot to measure the point intersection of the line of string and the projected laser line. The point data collected by changing robot configuration and sensor measuring are constrained to on a single straght line such that the closed-loop calibration method can be applied. The obtained calibration method is simple and accurate and also suitable for on-site calibration in an industrial environment. The method is implemented using Hyundai VORG-35 for its effectiveness.

• Korean Management Science Review
• /
• v.25 no.1
• /
• pp.43-53
• /
• 2008

This paper considers a profit-based unit commitment problem with fuel consumption constraint and maintenance cost, which is one of the key decision problems in electricity industry. The nature of non-linearity inherent in the constraints and objective functions makes the problem intractable which have led many researches to focus on Lagrangian based heuristics. To solve the problem more effectively, we propose mixed integer programming based solution algorithm linearizing the complex non-linear constraints and objectives functions. The computational experiments using the real-world operation data taken from a domestic electricity power generator show that the proposed algorithm solves the given problem effectively.

• Journal of Biosystems Engineering
• /
• v.11 no.1
• /
• pp.64-75
• /
• 1986

The objective of this study was to develop a mathematical model for optimum design of diversified farming systems which have the regional characteristics. For this purpose, the farming surveys were conducted for mainly 1984 agriculture. They were carried out on January and July 1985 for three villages of central region of Korea. The surveyed data were analyzed by systems analysis and the diversified farming systems were modeled. They consist of four and six croping patterns for paddy and upland, two and three kinds of fruit crop and livestock, and seven kinds of farm machinery for each work system. Then a mathematical model was developed by the multiple objective decision making (MODM) method in order to design optimum systems of diversified farming. It consists of 23 decision variables, two objective functions and nine constraint functions. The goals of objective function are maximization of agricultural incomes and power inputs of farm machinery, and the modeled factors for constraint function are arable land, available capital, labor, and land utilization.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.34 no.4
• /
• pp.113-121
• /
• 2009

In this paper, we consider the departure process from the open and nested tandem Queueing network with population constraint and constant service times. It is known that the Queueing network can be transformed into a simple Queueing network which can be easy to analyze. Using this simple Queueing network, upper and lower bounds on the interdeparture time are obtained. We prove that the variance of the interdeparture time is bounded within these two bounds. Validation against simulation data is shown that how it works the variance of the interdeparture time within two bounds. These bounds can be applied to obtain the better variance of the interdeparture time using a suitable method.