• Journal of the Korean Institute of Landscape Architecture
• /
• v.39 no.6
• /
• pp.67-75
• /
• 2011

This study was carried out to investigate the changes in citizen satisfaction with parks and green spaces in Daegu. Three surveys were conducted using the same measurement tools in 1986, 2001, and 2010. Major results are as follows: 1. The overall satisfaction level with parks and green spaces increased remarkably over the last25years. Satisfaction levels with city spaces overall were higher than that of nearby surrounding areas. 2. Diversity of green spaces was the most distinguished indicator in increasing level of satisfaction while the management level of green space facilities showed the lowest improvement. 3. The factor analysis for individual variables for satisfaction resulted in two factors: functions and physical conditions were categorized as one factor, and indicators for the planning of green spaces were the other. Using a regression model, the major variables found for satisfaction were diversity, management level of woods, quantitative level, function of static recreation, and management level of facilities, respectively. 4. Regarding satisfaction level by the type of green spaces, green spaces by streets showed a remarkable increase while green spaces in industrial areas showed the lowest improvement. A factor analysis for each type of green space resulted in 3 factors: green spaces of urban parks, green spaces of urban recreational facilities, and green spaces of each district including residential areas and industrial areas.

• 한국HCI학회:학술대회논문집
• /
• 2006.02a
• /
• pp.1099-1106
• /
• 2006

정신질환자들은 자기감정을 표현하는 능력의 결손을 보인다. 이러한 자기 감정표현기술은 정신질환자들을 위한 사회기술훈련 (Social Skill Training) 과정 중 하나로서 정상적인 사회생활로의 복귀를 위해 반드시 필요하다. 지금까지의 자기감정표현 훈련 및 평가 방법은 치료자 능력의 차이에 따른 주관적 판단이 개입될 수 있다는 문제점을 가지고 있다. 가상현실 (Virtual Reality)은 컴퓨터를 이용한 최신의 방법으로, 최근 자폐증이나 공포증 등의 정신질환 분야에도 적용되고 있다. VR 을 사용하면 상호작용을 할 수 있고, 다양한 환경과 자극을 제시할 수 있으며, 3 차원 랜더링을 통해 몰입감을 제공할 수 있다. 또한 저장된 파라미터들을 바탕으로 객관적 판단을 할 수 있는 기준을 제시할 수 있으며, 안전하고 시간과 공간적 제약이 적은 환경 내에서 과제를 수행할 수 있다. 이에 본 연구에서는 자기감정표현기술의 객관적 평가를 위한 가상현실 시스템을 개발하고 정신분열증 환자와 정상인을 대상으로 실험을 진행하였다. 가상현실은 크게 긍정적 상황과 부정적 상황으로 이루어 지는데 집, 카페, 빵집, 길거리 등 다양한 환경에서 가족, 친구, 직장동료 등의 아바타가 실험 참가자에게 말을 건네고 참가자는 적절한 시기에 자신의 감정표현을 하도록 구성하였다. 실험을 하면서 정서 (긍정적 상황 Vs. 부정적 상황)에 따른 자기감정표현에 대한 파라미터로서 아바타가 말하는 동안 참가자가 아바타의 말에 주목을 하는 정도 (아바타가 말하는 동안 참가자가 아바타의 얼굴을 쳐다보는 시간)와 자기감정을 표현을 하는 시간 (아바타의 말이 끝난 후 감정표현을 시작하는 시간과 감정표현시간)과 상대방 아바타를 주목하는 정도 (참가자가 자기감정을 표현하는 중 아바타를 쳐다보는 시간) 등을 측정하였다. 측정결과 정상인이 정신분열병 환자에 비해 아바타를 주목하는 시간이나 자기감정표현을 하는 시간이 더 긴 경향이 있었다. 또한 부정적 상황에서 정신분열병 환자와 정상인 모두가 긍정적 상황에 비해 말하는 아바타에 더 잘 주목하였고, 자기감정을 표현하는 시간도 더 긴 것을 확인 하였다. 따라서 본 연구에서 도출된 파라미터는 실험 참가자의 자기감정표현의 정도를 객관적으로 나타낼 수 있을 것으로 생각된다. 또한 정신분열병 환자의 자기 감정표현능력을 측정하는 도구로 사용될 수 있을 것으로 생각된다.

• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.3
• /
• pp.355-362
• /
• 2015

Purpose: To investigate the effects of the transmittance of diffusive blurson visual acuity and contrast sensitivity. Methods: Visual acuity and contrast sensitivity were measured by using Optec$^{(R)}$ 6500 in Healthy 30 subjects aged $22.83{\pm}0.50$ (male 13, female 17) who were recruited from university students. Cataract simulator was used as a tool for diffusive blur. Visual acuity and contrast sensitivity were measured with varying the transmittance of diffusive blur in order to simulate progression of cataract and concentration in fog. Results: Visual acuity was reduced proportionally with decreasing the transmittance of the diffusive blur as follows: $VA(T)=1.84{\times}10^{-2}T-0.645$. Contrast sensitivity was decreased in all spatial frequencies. Contrast sensitivity in a high spatial frequency band was a greater effect and was off the normal range of contrast sensitivity. The peak of contrast sensitivity was moved in the direction to low frequency. From an intersection point of contrast sensitivity function, we could calculated the transmittance of the diffusive blur being off the normal range and the shift to peak spatial frequency. The peak of contrast sensitivity function was observed to move from 6 to 3 cpd at transmittance of about 78.70%, the contrast sensitivities for all frequencies at transmittance of about 69.71% were deviated from the normal range. Conclusions: The transmittance of diffusive blur causes a reduction in visual acuity and contrast sensitivity, a deviation of normal range of contrast sensitivity, and a shift of peak contrast sensitivity. Therefore the more attention is required when suffering from cataracts or driving in fog.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.4
• /
• pp.361-372
• /
• 2016

The purpose of this study was to develop a STEAM-based science education program for children and to verify its effectiveness. An S-STEAM-based science education program for young children was developed through careful analysis of prior research on science education for young children and S-STEAM. The participants were 29 four-year-old children from daycare centers located in Seoul (an experimental group of 14 and comparative group of 15). The S-STEAM program was applied to the experimental group, while the control group went through a general science education course provided by the government. TTCT of Creative Thinking (TTCT: Figures A and B) was used as a research tool, and a multiple intelligence test tool was applied to teachers of the groups. Afterwards, analysis of covariance was implemented to find the S-STEAM program's effects. First, the results showed positive effects on overall creativity, as well as in fluency, originality, abstractness, elaboration, and openness components of creativity. Second, the results showed positive effects on overall multiple intelligences and its components of linguistic, musical, spatial, logical/mathematical, physical exercise, interpersonal, and naturalist intelligence.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.43 no.6
• /
• pp.127-137
• /
• 2015

Recent research has shown that university students experience severe stress and depleted directed attention due to study, social relationships, and economic dependency. Based on the stress reduction theory and the attention restoration theory, this study aims to investigate the effects of natural landscape on university students' stress and cognitive performance through a wide array of measurements including GSR(galvanic skin responsse), IBI(interbeat interval), ZIPERS(Zucherman Inventory of Personal Reactions), and mental arithmetic test. The restorative effects of natural landscape were compared with those of urban landscape. 128 university students participated in the study, and the data of 120 students was analyzed. The results showed that natural landscape was more restorative in relieving psychological stress and in enhancing cognitive performance than urban landscape, which evidenced the restorative effects of natural landscape. Therefore, it could be proposed that natural landscaping of the university campus contributes to students' stress reduction and cognitive enhancement. But such effects were not found in the two physiological measures(both GSR and IBI). Moreover, it was analyzed that urban landscape had a more beneficial effect than natural landscape for IBI, which might resulted from the participants' characteristics and the study landscape. Specifically, the young age span of the participants(average 23.8 years old) and the very natural setting of the university where they were enrolled might lead to the conflicting results in physiological measures. Also, the urban landscape used in the study had a sense of "scope", which is one of the Kaplan and Kaplan's restorative characteristics. Based on this opinion, it was suggested that future study should investigate the impact of the landscape type and contents as well as the participants' characteristics on the restorative effects of natural landscape.

• Tunnel and Underground Space
• /
• v.25 no.6
• /
• pp.496-504
• /
• 2015

Roadheader that excavates ground using pick cutters installed on the cutting head is one of the partial-face machines. A conical cutter among pick cutters is excavation tool decreasing the loss of cutter using tungsten carbide insert at the tip of the cutter and it has been widely used in the roadheaders. In this study, durability performance for three kinds of conical cutters was evaluated in copper mines composed of Manto and conglomerate. After field test, the visual inspection as well as the weight loss measurement of pick cutters was carried out to investigate the damage of pick cutters. In addition, CT scan and SEM were performed to check whether or not crack and apertures in pick cutters. As results, the conical cutter with hardfacing was evaluated as having the best durability performance and it was unable to find cracks in all cutters investigated.

• Journal of Industrial Convergence
• /
• v.21 no.4
• /
• pp.13-22
• /
• 2023

Due to COVID-19, organizations are rapidly changing the way they work by providing telecommuting and flexible work, and by expanding Smart Work spaces. In a Smart Work situation, workers have improved their job autonomy to choose their work methods, hours, and places. However, previous studies do not reflect the Smart Work situation and there are limitations to still using the previous job autonomy concept and measurements. To overcome these problems, this study derived job autonomy types such as methods, scheduling, criteria, time, and place applicable to Smart Work environments and verified that the five types of job autonomy have a statistically significant positive effect on Smart Workers' creative behavior. This study is meaningful in that it categorized job autonomy into five types applicable to Smart Work by adding temporal and spatial flexibility to the traditional job autonomy concept such as method, scheduling, and criteria autonomy and provided the basis for subdividing and evaluating the operation performance of Smart Work through multi-dimensional job autonomy verification.

• Progress in Medical Physics
• /
• v.14 no.1
• /
• pp.15-19
• /
• 2003

High dose rate (HDR) brachytherapy for treating a cervix carcinoma has become popular, because it eliminates many of the problems associated with conventional brachytherapy. In order to improve the clinical effectiveness with HDR brachytherapy, a dose calculation algorithm, optimization procedures, and image registrations need to be verified by comparing the dose distributions from a planning computer and those from a phantom. In this study, the phantom was fabricated in order to verify the absolute doses and the relative dose distributions. The measured doses from the phantom were then compared with the treatment planning system for the dose verification. The phantom needs to be designed such that the dose distributions can be quantitatively evaluated by utilizing the dosimeters with a high spatial resolution. Therefore, the small size of the thermoluminescent dosimeter (TLD) chips with a dimension of <1/8"and film dosimetry with a spatial resolution of <1mm used to measure the radiation dosages in the phantom. The phantom called a pelvic phantom was made from water and the tissue-equivalent acrylic plates. In order to firmly hold the HDR applicators in the water phantom, the applicators were inserted into the grooves of the applicator holder. The dose distributions around the applicators, such as Point A and B, were measured by placing a series of TLD chips (TLD-to-TLD distance: 5mm) in the three TLD holders, and placing three verification films in the orthogonal planes. This study used a Nucletron Plato treatment planning system and a Microselectron Ir-192 source unit. The results showed good agreement between the treatment plan and measurement. The comparisons of the absolute dose showed agreement within $\pm$4.0 % of the dose at point A and B, and the bladder and rectum point. In addition, the relative dose distributions by film dosimetry and those calculated by the planning computer show good agreement. This pelvic phantom could be a useful to verify the dose calculation algorithm and the accuracy of the image localization algorithm in the high dose rate (HDR) planning computer. The dose verification with film dosimetry and TLD as quality assurance (QA) tools are currently being undertaken in the Catholic University, Seoul, Korea.

• Economic and Environmental Geology
• /
• v.54 no.3
• /
• pp.373-387
• /
• 2021

In this study, the impact of clustered groundwater usage facilities and the proper amount of groundwater usage in the Daejeong-Hangyeong watershed of Jeju island were evaluated based on the data-driven analysis methods. As the applied data, groundwater level data; the corresponding precipitation data; the groundwater usage amount data (Jeoji, Geumak, Seogwang, and English-education city facilities) were used. The results show that the Geumak usage facility has a large influence centering on the corresponding location; the Seogwang usage facility affects on the downstream area; the English-education usage facility has a great impact around the upstream of the location; the Jeoji usage facility shows an influence around the up- and down-streams of the location. Overall, the influence of operating the clustered groundwater usage facilities in the watershed is prolonged to approximately 5km. Additionally, the appropriate groundwater usage amount to maintain the groundwater base-level was analyzed corresponding to the precipitation. Considering the recent precipitation pattern, there is a need to limit the current amount of groundwater usage to 80%. With increasing the precipitation by 100mm, additional groundwater development of approximately 1,500m³-1,900m³ would be reasonable. All the results of the developed data-driven estimation model can be used as useful information for sustainable groundwater development in the Daejeong-Hangyeong watershed of Jeju island.

• The Korean Journal of Nuclear Medicine
• /
• v.38 no.1
• /
• pp.74-84
• /
• 2004

Purpose: Since I-125 emits low energy (27-35 keV) radiation, thinner crystal and collimator could be employed and, hence, it is favorable to obtain high quality images. The purpose of this study was to derive the optimized parameters of I-125 SPECT using a new simulation tool, GATE (Geant4 Application for Tomographic Emission). Materials and Methods: To validate the simulation method, gamma camera developed by Weisenberger et al. was modeled. Nal(T1) plate crystal was used and its thickness was determined by calculating detection efficiency. Spatial resolution and sensitivity curves were estimated by changing variable parameters for parallel-hole and pinhole collimator. Peformances of I-125 SPECT equipped with the optimal collimator were also estimated. Results: in the validation study, simulations were found to agree well with experimental measurements in spatial resolution (4%) and sensitivity (3%). In order to acquire 98% gamma ray detection efficiency, Nal(T1) thickness was determined to be 1 mm. Hole diameter (mm), length (mm) and shape were chosen to be 0.2:5:square and 0.5:10:hexagonal for high resolution (HR) and general purpose (GP) parallel-hole collimator, respectively. Hole diameter, channel height and acceptance angle of pinhole (PH) collimator were determined to be 0.25 mm, 0.1 mm and 90 degree. The spatial resolutions of reconstructed image of the I-125 SPECT employing HR:GP:PH were 1.2:1.7:0.8 mm. The sensitivities of HR:GP:PH were 39.7:71.9:5.5 cps/MBq. Conclusion: The optimal crystal and collimator parameters for I-125 Imaging were derived by simulation using GATE. The results indicate that excellent resolution and sensitivity imaging is feasible using I-125 SPECT.