• Journal of Broadcast Engineering
• /
• v.16 no.2
• /
• pp.339-349
• /
• 2011

IBDI (Internal Bit Depth Increase) is able to significantly improve the coding efficiency of high definition video compression by increasing the bit depth (or precision) of internal arithmetic operation. However the scheme also increases required internal memory for storing decoded reference frames and this can be significant for higher definition of video contents. So, the reference frame memory compression method is proposed to reduce such internal memory requirement. The reference memory compression is performed on 4x4 block called the processing unit to compress the decoded image using the correlation of nearby pixel values. This method has successively reduced the reference frame memory while preserving the coding efficiency of IBDI. However, additional information of each processing unit has to be stored also in internal memory, the amount of additional information could be a limitation of the effectiveness of memory compression scheme. To relax this limitation of previous memory compression scheme, we propose a selective merging-based reference frame memory compression algorithm, dramatically reducing the amount of additional information. Simulation results show that the proposed algorithm provides much smaller overhead than that of the previous algorithm while keeping the coding efficiency of IBDI.

• Journal of Broadcast Engineering
• /
• v.17 no.4
• /
• pp.695-706
• /
• 2012

The purpose of this paper is to propose a service system for a digital hologram video, which has not been published yet. This system assumes the existing service frame for 2-dimensional or 3-dimensional image/video, which includes data acquisition, processing, transmission, reception, and reconstruction. This system also includes the function to service the digital hologram at the viewer's view point by tracking the viewer's face. For this function, the image information at the virtual view point corresponding to the viewer's view point is generated to get the corresponding hologram. Here in this paper, only a prototype that includes major functions of it is implemented, which includes camera system for data acquisition, camera calibration and image rectification, depth/intensity image enhancement, intermediate view generation, digital hologram generation, and holographic image reconstruction by both simulation and optical apparatus. The proposed prototype system was implemented and the result showed that it takes about 352ms to generate one frame of digital hologram and reconstruct the image by simulation, or 183ms to reconstruct image by optical apparatus instead of simulation.

• Journal of Broadcast Engineering
• /
• v.18 no.2
• /
• pp.225-236
• /
• 2013

3D contents could cause unique 3D visual fatigue. Screen disparity, image blurring, and crosstalk are known to be the three major factors responsible for the fatigue. Among these, screen disparity and image blurring are content factors, that is, one can directly manipulate contents themselves to handle visual fatigue caused by these two factors. On the other hand, because crosstalk is closely tied to physical characteristics of 3D display, it is difficult or even impossible to reduce crosstalk-driven visual fatigue unless one replaces 3D display itself (for example, from active to passive display). However, the effects of crosstalk on 3D visual fatigue depends on visual stimulus features (that is, contents), and thus it is possible to manipulate stimulus features in order to handle visual fatigue caused by crosstalk. Hence, this research tested the effects of visual stimulus features on crosstalk (which then causes 3D visual fatigue). Using relative depth discrimination task, we tested the effects of stimulus-background contrast, background texture density, and screen disparity on the degree of perceived crosstalk. The results showed that crosstalk decreases with presence of background texture and with less degree of screen disparity.

• Journal of Bio-Environment Control
• /
• v.10 no.4
• /
• pp.232-236
• /
• 2001

Four air temperature levels of 23, 25, 27 and 29$^{\circ}C$, three humidity levels of 85, 90 and 95% R.H. at photosynthetic photon flux (PPF) of 50 $\mu$mol.m$^{-2}$ .s$^{-1}$ were provided to investigate the effect of vapor pressure deficit on the evapotranspiration rate (EVTR) and graft-taking of watermelon grafted seed-increase. Thus EVTR of grafted seedlings increased with increasing air temperature at high humidity of 95%R.H. At relatively low humidity of 85% R.H., grafted seedlings showed a high EVTR and some wilting of scions was observed at this condition. This result would be ascribed to the low supply of water to vascular bundles according to the insufficient joining of scions and rootstocks. Differences in EVTR between 90% R.H. and 95% R.H. were not observed. Grafted seedlings showed high graft-taking at high relative humidity. Relative humidity had highly influenced to the graft-taking as compared to the air temperature. Graft-taking increased with decreasing vapor pressure deficit. Graft-taking greater than 90% was found at vapor pressure deficit less than 0.4kPa which could be obtained at humidity higher than 90% R.H. Therefore it is required to control the humidity higher than 90% R.H. for suppressing EVTR of grafted seedlings and preventing some wilting of scoins and thus enhancing the graft-taking of grafted seedlings.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1998.05a
• /
• pp.153-157
• /
• 1998

무등산 수박의 유묘 생산에 있어 적정 배양액 농도를 구명하기 위하여 일본원시균형배양액을 기준으로 하여 NO$_3$-N, K 및 Ca의 농도별 첨가량에 따른 유묘생장반응을 조사하였다. 1. 배양액내 질소농도을 증가시킬수록 초장, 엽면적, 엽수, 엽장, 엽폭이 증가하였으며 생체중과 건물중도 증가하였다. 2. 배양액내 칼륨의 농도를 증가시켰을 경우 수박 유묘의 초장은 200ppm까지는 약간 증가하지만 엽면적, 엽수, 엽장, 생체중 및 건물중은 200ppm이상으로 증가시키면 감소하는 경향이었다. 3. 칼슘처리의 경우 농도의 증가가 생장의 증가를 나타내지는 않았으며 원시균형 배양액의 표준이라 할 수 있는 80ppm처리구의 생장이 양호한 것으로 나타났다. 4. 배양액(일본원시균형배양액 1/2농도)에 N의 농도를 200ppm으로 증가시킬 경우 수박유묘의 엽병내 N, K 및 Mg의 함량이 증가하였지만 P 및 Ca의 증가나 감소의 경향은 보이지 않았다. 5. K의 농도를 100ppm으로 증가시킬 경우 수박유묘의 엽병내 N, K 및 Mg의 함량이 증가하였지만 P 및 Ca의 증가나 감소의 경향은 보이지 않았다. 5. K의 농도를 150ppm으로 증가시킬 경우 수박유묘의 엽병내 N, K 및 Mg의 함량이 증가하였지만 P 및 Ca의 증가나 감소의 경향은 보이지 않았다. 그러나 200ppm이상으로 증가시킬 경우 N과 Mg의 감소가 나타났다. 6. 양액내 Ca의 농도를 증가시킬수록 엽병내 N, K Ca 및 Mg의 농도가 증가하는 반면 P의 경우 거의 변화가 없었으며,N의 경우는 200ppm 이상의 농도에서 감소하는 경향을 나타내었다. Mg의 경우는 150ppm까지는 함량의 변화가 없었지만 200ppm 이상의 처리구에서 급격한 함량증가를 나타내었다.~21.2ml가 흘러나와 배지의 공극이 일정하지 않아 시간당 통과하는 양이 일정하지 않았다고 생각되었다. $\bigcirc$ 펄라이트 : 합섬A(비스코스+레이온)급액천의 유입은 소(1$\times$60cm)에서 21.8ml, 중(2$\times$60cm) 33.5ml, 대(3$\times$60cm) 43.4ml가 통과되었고 합섬(폴리에스텔)에서는 19.0~30.7ml로서 급액천의 규격에 따라 통과되는 차이가 있었다. 배지가 규격화되어 있어 급액천의 규격별로 일정하게 유입되었으며 급액천의 재질이 유입에 영향을 미친 것으로 사료되었다. (2) 급액관과 베드상과의 높이에 따른 유출양 : 급액과 베드상과의 낙차가 클수록 유출이 증가함을 알수 있었으나 합섬C(인견)실험구에서는 낙차가 유출에 영향을 미치지 않았다. (4) 급액된 양액의 EC 및 pH조사 : 급액된 양액의 EC 및 pH에 전혀 변화가 없어 재배 적응에 문제가 없을것으로 사료되었다.이가 가장 이상적인 것으로 생각된다.세포수에 대한 내부세포괴세포(ICM/total cells)가 20~40% 범주에 드는 비율은 처리구가 대조구보다 낮은 결과를 나타냈다. 결론적으로 돼지난포란을 이용하여 체외성숙을 유기할 때 효과적인 cysteamine의 농도는 50$\mu$M이 적당하며, 초기배발달을 유기할 때의 효과적인 cysteamine의 농도는 25~50$\mu$M인 것으로 판단된다.N)A(N)/N을 제시하였다(A(N)=N에 대한 A값). 위의 실험식을 사용하여 헝가리산 Zempleni 시료(15%$S_{XRD}$)의 기본입자분포로부터 %$S_{XRD}$를 계산한

• Journal of Bio-Environment Control
• /
• v.26 no.2
• /
• pp.108-114
• /
• 2017

The effect of 1-methylcyclopropene (1-MCP) at $1.0{\mu}L{\cdot}L^{-1}$ was compared with control and $10{\mu}L{\cdot}L^{-1}$ ethylene treatment to evaluate softening control of apple (Malus ${\times}$ domestica Borkh.) fruit for 180 days at $0.5^{\circ}C$ in the air, followed for 28 days at a room temperature. 1-MCP or 1-MCP+ethylene treatment maintained high fruit titratable acidity and firmness after 120 days during the cold storage, which was similarly observed for 28 days at a room temperature. 1-MCP treatment maintained fruit firmness more than 14 N during the cold storage and shelf-life at room temperature. Fruit surface red color was not consistently affected by the treatments during the cold storage but enhanced more than 4.0 by 1-MCP at 21- and 28-days of room temperature. Control or ethylene treatment advanced overall preceeding of fruit softening as rapid ethylene production and respiration rates at 90 days during the cold storage increased to a climacteric maximum. Therefore, pre 1-MCP-treated fruit maintained high fresh condition at a long-term low storage + approximately one month room temperature-storage under $10{\mu}L{\cdot}L^{-1}$ ethylene treatment.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.12 no.2
• /
• pp.31-40
• /
• 2017

This study validate effectiveness of Online Entrepreneurship Education based on PBL(Problem-based Learning) and flipped learning. This study reveals online education of entrepreneurship based on PBL and flipped learning method has positive effect on personal entrepreneurship, will to be an entrepreneur, and problem-solving skills. First, the results show that entrepreneurship education based on PBL and flipped learning can improve entrepreneurship more than a previous learning method. Second, PBL and flipped learning based online education affects will to be an entrepreneur in positive way. Experimental group who experienced problem solving activity and flipped learning has more will to be entrepreneur than control group who takes previous learning method. Lastly, PBL and flipped learning method based entrepreneurship education also has positive effect on personal problem-solving techniques. This results show that online entrepreneurship education based on PBL and flipped learning has positive impacts on entrepreneurship, will to be an entrepreneur, and improving problem-solving skills significantly.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.12 no.2
• /
• pp.87-94
• /
• 2017

The utilization of the achievements derived from the national R & D project is a key task of the science and technology industry policy that should lead the national economic growth by enhancing the investment efficiency of the national R&D. Although Korea has implemented various programs supporting technology transfer, commercialization, Performance is not sufficient. One of several causes may include inflexibility of a small or medium-sized company Priority System. This study is exploratory research on the directions for improving the current a small or medium-sized company Priority System. Results: First, Because the current SMEs Priority System contributes positively to enhancing SMEs R&D capability, We have to keep the system in principle. However, it is necessary to improve the direction of giving the strategic flexibility of the system so that the system is not operated formally. First, it is appropriate to make an exceptional contract with a person other than a small or medium-sized company, if a small and medium-sized company is not suitable for a technology execution contract due to the nature of technology. Second, it is desirable to consider the fulfillment of the obligations of this system when "sufficient efforts" are made to find a technical user.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.12 no.2
• /
• pp.41-54
• /
• 2017

The purpose of this study is to find out how the support system of the government and the local governments for enhancing the success rate of the startup firms affected the performance of the enterprises according to the behavior characteristics of the founders. It is divided entrepreneurial support system into entrepreneurial policy support such as entrepreneurial education, mentoring and consulting, and funding of startup support such as policy fund and R & D fund, distinguished the behavior of founder into behaviors for discovery of entrepreneurial opportunities and behaviors for exploiting entrepreneurial opportunities. In order to analyze whether it affects the corporate management performance, a research model was created based on the previous research and hypotheses were set up, and the hypotheses were verified based on this questionnaire. The results of this study are as follows: First, it is found that the support for entrepreneurial policy has a positive effect on the behavior characteristics of entrepreneur. Second, it is found that the startup support such as policy fund affects the behavioral characteristics for finding the opportunity of the founder, but it does not affect the behavioral characteristics for the opportunity exploit. Third, it was found that the behavior characteristics of entrepreneur founding opportunity and exploition of entrepreneurial opportunity influenced the performance of the company. According to the this study, the following conclusion were obtained, First, it is necessary to apply different policies according to the stage of growth of startup companies. Second, startup companies grow through the stages of development of new technologies and ideas, commercialization, and marketing, at each stage, entrepreneur must overcome the so-called Death Valley, which requires funding.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.13 no.4
• /
• pp.1-12
• /
• 2018

During few decades, Korean economy has been growing with heavy and manufacturing industries. However, the economy meets limitations of growth rate, and employment rate. The Korean government has been trying to overcome these limitations using development of venture businesses and re-organization of industrial ecosystem. These efforts make high survival rate of recent venture companies. There are previous researches about relation between characteristics of entrepreneur and managerial performance, there are several limitations. Firstly, most of papers were based on survey with specific region or industry. Secondly, related researches were carried out with unable to distinguish among firm's survival periods. This paper uses the '2017 Survey of Korea Venture Firms' data that is approved by the Korean government. This data includes whole industries and survival periods. The aim of this research is finding the effect of characteristics of entrepreneur on managerial performance of venture firms by different survival periods using data envelopment analysis (DEA). If entrepreneur has doctoral degree, the firm's managerial performance is lower than bachelor degree. In addition, over 10 years of working career, and joint-venture have positive effect on firm's performance. This paper can provide valuable information to venture related policy makers and investment decision makers.