• Electronics and Telecommunications Trends
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• v.26 no.2
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• pp.61-74
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• 2011

증강현실은 1960년대 중반부터 시작된 기술이지만 그동안은 제한된 범위의 응용을 중심으로 고성능 고정 단말 상에서 기능을 구현하여 왔다. 그러나 최근 5년 사이 카메라와 GPS 등의 다양한 센서를 내장한 모바일 단말과 스마트폰의 보급이 확산이 되고, 빠른 모바일 인터넷을 이용한 인터넷서비스들과 융합된 다양한 기능들이 선보이면서, 모바일 증강현실 분야는 급속히 확산되고 있다. 초기의 증강현실 서비스는 가상객체를 효과적으로 보여주기 위한 관점이었다면, 최근의 모바일 증강현실 서비스들은 다양한 인터넷 서비스와 정보들을 효과적으로 브라우징하거나 센서 정보 등을 기반으로 모바일 단말을 이용해 편리한 증강 인터페이스를 사용하도록 하는 것에 보다 많은 초점을 맞추고 있다. 본 고에서는 이러한 모바일 증강현실 기술 동향과 관련 표준화 동향을 고찰함으로써 미래 모바일 증강현실 기술의 진화 방향과 그 의미를 살피고자 하였다.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.101-104
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• 2000

본 논문은 중거리 수중표적이 고정 설치된 수신기에 접근 시 표적신호의 다중경로에 신호변형을 일으키며, 특히 신호의 변형 중 도플러효과를 변화정도를 신호모의를 동하여 분석하였다. 동해의 동계와 하계의 대표적인 음속구조에 따른 고유음선(eigenray)의 도플러 주파수를 계산하였다. 수중표적의 속도는 12노트, 주파수는 135Hz, 350Hz, 신호는 정현파로 가정하여 신호모의를 하였다. 그 결과 해저면 반사가 한번인 음선은 수신신호에 주로 Vp-doppler를 형성하였고 두 번인 음선은 주로 Down-doppler를 형성하였다.

• 한국데이터정보과학회:학술대회논문집
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• 2001.10a
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• pp.25-33
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• 2001

This paper suggests a generalized logit model with mixed effects for analysing frequency data in multi-contingency table. In this model nominal response variable is assumed to be polychotomous. When some factors are fixed but condisered as ordinal and others are random, this paper shows how to use baseline-category logits to incoporate the mixed-effects of those factors into the model. A numerical algorithm was used to estimate model parameters by using marginal log-likelihood.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1436-1437
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• 2006

탄소 나노튜브는 기계적인 강도가 크고, 표면적이 넘으며 전기전도도가 우수할 뿐만 아니라 화학적으로도 안정하기 때문에 최근 여러분야에 적용하려는 연구가 활발히 진행되고 있는 나노물질이다. 특히 바이오센서에서 탄소 나노튜브는 작업 전극의 활성을 증대시키는 물질로써, 안정적인 효소 고정화에 기여하는 reservior로써 그리고 반응에서 생성된 전자를 전극에 효과적으로 전달하는 매개체로써 이용되고 있다. 본 연구에서는 다중벽 탄소 나노튜브(multi-walled carbon nanotube ; MWNT)를 화학처리하여 작용기를 유도한 후 효소와 반응시킨 용액으로 스크린 프린팅 방법으로 제작된 탄소전극의 표면을 개질하는 방법으로 바이오센서를 제작하였다. 이렇게 제작된 바이오센서를 탄소 나노튜브를 이용하지 않은 바이오 센서와 전기화학적으로 분석한 결과 감도가 약 3배정도 증가하는 결과를 얻을 수 있었다. 이것은 효소반응 시 발생된 전자가 나노튜브를 통해서 전극에 효과적으로 전달됨을 의미한다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.1-10
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• 2011

This study was conducted to compare the growth of Zoysia japonica depending on different soil treatments in Saemangeum sea dike, which is filled with dredged soil. Zoysia japonica was planted using sod-pitching method on the control plot. On plots which were treated with forest soil and soil improvement, Zoysia japonica seeds were sprayed mechanically. Sixteen months after planting, coverage rate, leaf length, leaf width, and root length were measured and analyzed. Also, three Zoysia japonica samples per plot were collected to analyze nutrient contents. Coverage rate was 100% in B treatment plot(dredged soil+$40kg/m^3$ soil improvement+forest soil), in C treatment plots (dredged soil+$60kg/m^3$ soil improvement+forest soil), and D treatment plots (dredged soil+$60kg/m^3$ soil improvement), while only 43% of the soil surface was covered with Zoysia japonica on control plots. The width of the leaf on C treatment plots (3.79mm) was the highest followed by D treatment (3.49mm), B treatment (2.40mm) and control plots (1.97mm). Leaf and root length of D treatment was 30.18cm and 13.18cm, which were highest among different treatments. The leaf length of D treatment was highest followed by C, B, and A treatments. The root length of D treatment was highest followed by C, A, and B treatments. The nitrogen and phosphate contents of the above ground part of Zoysia japonica were highest in C treatment, followed by D, B, and A treatments. The nitrogen and phosphate contents of the underground part of Zoysia japonica were highest in D treatment, followed by C, A, and B treatments. C and D treatments showed the best results in every aspect of grass growth. The results of this study could be used to identify the cost effective way to improve soil quality for soil surface fixation on reclaimed areas using grass species.

• Geophysics and Geophysical Exploration
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• v.12 no.3
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• pp.225-232
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• 2009

As part of seismic experiments investigating crustal velocity structures of the Korean peninsula, permanent (fixed) seismographs of the Korea Meteorological Administration (KMA) network recorded seismic signals from four and eight large explosions in Korean Crustal Research Team (KCRT) profiles shot in 2004 and 2008, respectively. Among the seismograms recorded by 43 velocity sensors and 103 accelerometers at KMA stations distributed throughout the southern Korean Peninsula, 156 records with epicentral distances less than 120 km and high signal-to-noise ratios were analyzed to determine velocity anisotropy of the Pg phase. Relative elevation corrections of -101.6 to 105.3 ms were made using velocity information derived from the 2004 KCRT profile data and differences in elevation between the permanent KMA stations and the temporary stations in the KCRT profiles at the same source-receiver offsets. To remove site effects, receiver-station corrections of -89.6 to 192.2 ms were additionally made to the KMA station data by subtracting the average differences in traveltimes between KMA stations and portable stations at the same offsets for all available shots with different azimuths. With the exception of anomalously fast velocities along trends of the Chugaryeong fault zone and the Okchon fold belt and anomalously slow velocities in the regions of high terrestrial heat near Yeongduk and Ulsan, the analysis of crustal velocity anisotropy using the Pg phase indicates overall isotropy in the southern half of the Korean peninsula.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.132-138
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• 2016

The objectives of this study were to infer the parameters of forest stand growth functions of STEMS for Cryptomeria japonica stands of Jeju Hannam Experimental Forest, Korea Forest Research Institute, and to investigate the effects of thinning regimes on the patterns of stand growth and carbon absorption. The forest stand growth functions for the potential diameter growth, modifier, crown ratio and mortality are the major ones composing the independent-tree/distance-free forest stand growth simulator, STEMS. The parameters were inferred using the sets of growth data obtained from stem analyses of 39 trees, chosen from 13 sample plots of the forest stands. The effects of thinning regimes on the patterns of stand growth and carbon absorption were investigated by simulating the stand growth patterns of the case study stand with 3 different thinning regimes: no-thinning, early thinning with low intensity and late thinning with high intensity using the simulator. According to the results of the analyses, the different thinning regimes cause significant effects on the growth patterns of average DBH, average height, diameter distribution and stand volume as well as the amount of carbon absorptions.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.139-148
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• 2016

The purpose of this study was to evaluate critically the effects of forest experience on young children using meta-analysis. To test this, a total 30 studies were identified, and mean effect size of variables was calculated by applying Fixed-effect model. As a result, the overall effect size of forest experience on young children was 0.797. The effect sizes of daily type as a program type had an effect than experience type at the level of .939. And also the effect sizes of period program (more 4month), number of participants (10-20people), program time (180minute), dependant variables (multiple intelligence) yield effects 0.972, 0.980, 1.138 and 0.957 respectively. As the result, this study implies a way which is to derive effectively further studies on the forest experience on young children.

• Journal of Korean Orthopaedic Sports Medicine
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• v.2 no.1
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• pp.28-36
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• 2003

Purpose: To determine and to compare the effects of cyclic loading on the fixation strength of different femoral fixation methods in ACL reconstruction. Materials and Methods: Biomechanical test using an Instron(R) machine (Model No.5569. Mass, U.S.A) were carried out to compare the pull out strength of six different femoral fixation techniques after a cyclic loading in 72 Yorkshire pig knees. The graft-bone complex was cyclically loaded between 30N and 150N at 50 mm/min rate for 1000 cycles and maximal tensile testing was performed. A preload of 30N was applied to the graft along the axis of the tunnel 15 minutes. ANOVA and the Duncan multiple comparison test was used for the statistical analysis. Results: The mean maximum tensile strength of femoral fixation before and after the cyclic loading test were 1003.4$\pm$145N and 601.1$\pm$154N in hamstring-LA screw(R) group, 595.5$\pm$104N and 360.7$\pm$56N in hamstring-Bioscrew(R) group, 1431.7$\pm$135N and 710.7$\pm$114N in hamstring-Semifix(R) group, 603.6$\pm$54N and 459.1$\pm$46N in hamstring-Endobutton(R) fixation group, 1067.4$\pm$145 and 601.8$\pm$134N in the BPTB-Titanium interference screw group, and 987.1$\pm$168N and 588.7$\pm$124N in the BPTB-Bioscrew(R) group. And these data illustrated that cyclic loading reduces the maximum tensile strength by 40 $\%$, 39 $\%$, 50 $\%$, 24 $\%$, 44 $\%$, 40 $\%$ respectively. Conclusions: With the results of these experiments it should be emphasized that rehabilitation exercises after anterior cruciate ligament reconstruction should be executed with precaution as the repetitive flexion and extension of the knee would compromise the maximum tensile strength of the graft tendon.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.796-808
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• 2021

This study examines the relationship of disability acceptance, interpersonal skill with job satisfaction to improve the job satifaction of the disabled in wage work. The study also examines the moderated effect of employment type and the mediated effect of interpersonal skill. the research used data from the 2nd wave of the Panel Survey of Employment for the Disabled(PSED) in Years 1-4(2016-2019), AMOS 22 was to analyze the paths between variables. The result of the study are as follows. First, The job satisfaction of the disabled in wage work differed significantly in educational background, age group, and working period. But, there was no significant difference in gender. Second, disability acceptance has been shown to have a significant positive effect on job satisfaction. Third, interpersonal skill have been shown to have a positive mediated effect in the relation between disability acceptance and job satisfaction. Fourth, the relation between disability acceptance and job satisfaction revealed that employment type have a negative significant moderating effect. Based on the result, Welfare practices for disability acceptance, interpersonal skill, and employment were proposed in order to promote job satisfaction for the disabled.