• Journal of Industrial Technology
• /
• v.31 no.A
• /
• pp.109-112
• /
• 2011

In this paper, we proposed a planar reversed triangle monopole antenna for UWB(Ultra Wideband) communication. RF-60A substrate of 0.64 mm thickness and 6.15 relative permitivity and 0.035 mm conductor of thickness and loss tangent 0.0025 is used for implementation. We have used Ansoft $HFSS^{TM}$(High Frequency Structure Simulator) to simulate the proposed antenna. The proposed antenna showed return losses about -10 dB, nearly omni-directional radiation patterns and maximum gains are over -5 dBi at the frequency band from 3.1 GHz to 10.6 GHz for ultra wide band communication.

• Progress in Superconductivity
• /
• v.3 no.2
• /
• pp.178-182
• /
• 2002

Superconducting four-element patch array antenna was designed and fabricated using $high-T_{c}$ superconducting (HTS) thin film. The array antenna has single-feed circularly polarization and a resonance frequency of 11.85 GHz fur satellite communication system. To fabricate this antenna $YBa_2$$Cu_3$$O_{7-x}$(YBCO) superconducting thin films were deposited using rf-magnetron sputtering technique. Sequential rotation technique based on radiation elements($0^{\circ}$ , $90^{\circ}$, 1$80^{\circ}$, $270^{\circ}$ phase delay) was utilized to achieve circularly polarization. Simulated and measured results, the analysis on resonant frequency(fr), return loss, and bandwidth are presented. The results show that 10 dB return loss bandwidth of the array antenna is 11.04 GHz~12.59 GHz (13.15%) and 3dB axial ratio bandwidth is 11.42~12.52 GHz (9.2%).).).

• Korean Institute of Interior Design Journal
• /
• v.22 no.1
• /
• pp.256-264
• /
• 2013

A bathroom in house has been stressed not only as a space for physiology and hygiene but also leisure and healthcare. However, the bathroom is the most likely space where an elderly person can have an accident and it is uncomfortable space for them because of their deteriorating physical ability. So the purpose of this study is to help the elderly use their bathroom conveniently by providing smart service. Therefore, we carry out 18 smart service patterns that contain assistive devices and sensors for bathroom. Considering applicability and frequency, from among these service patterns, we suggest 4 service patterns. First is a fall prevention service. This service helps elderly use the bathroom safely at night. Second is a getting ready to go out service. This service helps the situation that elderly use the bathroom after getting up in the morning. Third is a security service in daily life especially before or after meals. And final is a service regarding personal hygiene service after returning home. This service helps to shower or bathe after return home. These services have positive influence in medical expense reductions, good health care and self-reliance of elderly.

• Journal of Families and Better Life
• /
• v.23 no.3 s.75
• /
• pp.153-167
• /
• 2005

This study was conducted to help develop women's human resources and promote married women's return to workforce. Using various data, we examined the patterns of Korean women's economic activities over the lifecycle, career discontinuation and return to the workforce. We also interviewed twenty full-time housewives who wanted to return to workforce. The interview questions included reasons for seeking employment, desired working conditions, and difficulties in finding a job. Major findings are as follows: First, there were two groups with respect to reasons why they want employment One was an economic need such as earning basic living expenses and supporting the family. The other was self-realization and social participation. Second most women wanted to do unskilled labor such as housekeeping work, whereas some young or well-educated women looked for a professional job. Third, married women preferred part-time jobs, which were compatible with their family care demands. Most of them wanted a workplace located close to home. The women with child-care responsibility preferred working at home. Fourth, regarding difficulties of returning to workforce, they pointed out vocational ability problems due to their career discontinuation, social prejudice such as gender discrimination and psychological pressure in maintaining work and family at the same time. In order to promote employment of married women, it is required not only to change social prejudices but also to increase effectiveness in policy implementation. In addition, counseling for job-search and vocational ability training programs should be provide.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.5
• /
• pp.549-556
• /
• 2015

In this paper, design and fabrication for inset fed microstrip patch antennas applied to the $3{\times}3$ array CSLR and eight CSLR, respectively, to the ground plane are studied. The theoretical results are compared to the experimental results for the return loss and radiation pattern. For 'CSLR 09' antenna, the theoretical result for the resonant frequency and the return loss are 2.82 GHz and - 25.35 dB, respectively. The experimental results are obtained for a 2.885 GHz, -30.72 dB. Theoretical results for the resonant frequency and the return loss of the 'CSLR 08' antenna are 2.82 GHz, -16.77 dB, respectively, and the experimental results are obtained for a 2.885 GHz, -14.90 dB. In addition, E-plane and H-plane radiation patterns in comparison with designed and fabricated antennas are in good agreement.

• Korean Journal of Social Welfare
• /
• v.64 no.4
• /
• pp.359-381
• /
• 2012

This Study aims to investigate the patterns and causes of the time to return-to-work(RTW) of the injured workers. This study collected data with structured questionnaires and finally included 791 injured workers. The Kaplan-Meier method is used for describing the patterns of the time to RTW after the injury and after claim closure. And the Cox regression is used to identify significant factors on the time to RTW after the injury and after claim closure. The results show that amom the all respondents, the 2.65% returned to work within 1 month, 28.82% within 6 months, 50.95% within 1 year, 71.69% within 2 years after the injury, and the 29.46% of the all repondent returned to work before claim closure or directly after the claim closure, the 36.41% returned to work within 1 month, 56.64% within 6 months, 67.54% within 1 year after the claim closure. And the Cox regression results of the time to RTW after the injury show that the time to RTW affected by gender, age, income, the retirement during the treatment, the RTW to the company at injured time, injury type, surgery, the claim duration, disability ratings, vocational training. Also, the Cox regression results of the time to RTW after the claim show that the time to RTW affected by gender, age, income, the return to the company at injured time, disability ratings, vocational training. As a result, some implication and policies are suggested for reducing the time to RTW of the injured workers.

• Asia pacific journal of information systems
• /
• v.27 no.4
• /
• pp.233-244
• /
• 2017

IT portfolio, meaning the ratio of investment with four different purposes of IT, is widely used for evaluating the adequacy of investment and its performance within firms. Despite of such a useful framework looking at investment on IT, IT portfolio in agriculture industry seems to be differentiated from other industries. In this study, we compared IT portfolios of farms: grain, field fruit and vegetable, greenhouse fruit, greenhouse vegetable, beef cattle and pig. We classified farms by their return on equity (ROE) in order to analyze the relationship between IT portfolio of each crop and performance. Then, we found patterns of IT portfolios of top-performance farms compared to all farms for each agricultural product. Lastly, peculiarities of each crop are interpreted and discussed to find out top-performance farms' IT investment patterns. From our study, it could be inferred that monotonous IT investments may not be as effective.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2003.09a
• /
• pp.372-375
• /
• 2003

The incidence of blindness resulting from diabetic retinopathy has significantly increased despite the intervention of insulin to control diabetes mellitus. Early signs are microaneurysms, exudates, intraretinal hemorrhages, cotton wool patches, microvascular abnormalities, and venous beading. Advanced stages include neovascularization, fibrous formations, preretinal and vitreous microhemorrhages, and retinal detachment. Microaneurysm count is important because it is an indicator of retinopathy progression. The purpose of this paper is to apply data mining to detect diabetic retinopathy patterns in routine fundus fluorescein angiography. Early symptoms are of principal interest and therefore the emphasis is on detecting microaneurysms rather than vessel tortuosity. The analysis does not involve image-recognition algorithms. Instead, mathematical filtering isolates microaneurysms, microhemorrhages, and exudates as objects of disconnected sets. A neural network is trained on their distribution to return fractal dimension. Hausdorff and box counting dimensions grade progression of the disease. The field is acquired on fluorescein angiography with resolution superior to color ophthalmoscopy, or on patterns produced by physical or mathematical simulations that model viscous fingering of water with additives percolated through porous media. A mathematical filter and neural network perform the screening process thereby eliminating the time consuming operation of determining fractal set dimension in every case.

• Journal of electromagnetic engineering and science
• /
• v.5 no.3
• /
• pp.105-111
• /
• 2005

This paper presents the basic characteristics of a cutoff cavity-backed aperture antenna with a feed post and a parasitic post inserted parallel to the aperture. It is shown that this type of antenna forcibly resonates the cutoff cavity by adding a single external reactance to the parasitic post. The Galerkin's method of moments is used to analyze integral equations for the unknown electric current on each post and the aperture electric field on the aperture. The value of an external reactance for forced resonance is analytically obtained by deriving a determining equation. Also the current distribution on each post, aperture electric field distributions, and the radiation patterns are discussed. The theoretical analysis is verified by the measured return loss and radiation patterns.

• Water for future
• /
• v.29 no.3
• /
• pp.207-216
• /
• 1996

The subject research attempts to evaluate the variations of total runoff volume, peak flow, and travel time depending on the urbanhization, return periods and rainfall patterns under the situations that the preparation of a large residential site at the lowland areas of the downstream of Dongsu stream in Bupyung-Gu, Incheon city is progressed and the area will be eventually fully developed. The ILLUDAS model was used for the runoff analyses based on 3 differend steps of urbanization and 4 different types of Huff's quantile according to rainfall patterns is Huff's 4 quantile, Huff's 2 quantile, Huff's 3 quantile and Huff's 1 quantile. Under the 80 and 90 % of urbanization to the 70% of urbanization, the mean increasing ratio of total runoff volume for each case is 3.5 and 5.5 %, that of peak flow is 4.2 and 8.8%, and the mean decreasing ratio of travel time is 4.4 and 10.1%, respectively. The mean increasing ratio of total runoff volume according to the return periods is 3.0 and 5.4%, that of peak flow is 3.9 and 8.0% under the same conditions of urbanization.