The video game Tetris is one of most popular game and it is well known that its game rule can be modelled as MDP (Markov Decision Process). This paper presents a DQN (Deep Q-Network) based game agent for Tetris game. To this end, the state is defined as the captured image of the Tetris game board and the reward is designed as a function of cleared lines by the game agent. The action is defined as left, right, rotate, drop, and their finite number of combinations. In addition to this, PER (Prioritized Experience Replay) is employed in order to enhance learning performance. To train the network more than 500000 episodes are used. The game agent employs the trained network to make a decision. The performance of the developed algorithm is validated via not only simulation but also real Tetris robot agent which is made of a camera, two Arduinos, 4 servo motors, and artificial fingers by 3D printing.

Anther culture is useful and significant tool for producing haploid or doubled haploid (DH) plants in crop breeding system. Androgenesis is the way of inducing haploid and DH plants from anther (immature pollen) or microspore culture. In vitro androgenesis is efficient technique for introducing complete homozygous lines in one generation, thus less time and expense could be necessary than conventional plant breeding. In maize, anther culture is important system for shortening the breeding cycle and enhancing selection efficiency. Anther culture technique is also applicable to various researches such as molecular genetics, genetic engineering, genomics, and plant biotechnology. We review the past and present studies on anther culture and provide useful information for future researches on androgenesis in maize. The combination of androgenesis with other techniques such as molecular breeding and biotechnology is producing a variety of variety of maize species. In addition, we suggest strategy to develop androgenesis technique adapted to Korean research environment.

This study was conducted to evaluate maize downy mildew resistance using spreader row technique in Cambodia. A total of forty maize lines were used in this experiment. Seven Korean varieties and seven breeding lines showed high infection rates (80~100%) and highly susceptible (HS) to downy mildew disease in both spring and fall. Also most of nested association mapping (NAM) parent lines were highly susceptible (HS). Meanwhile three inbred lines, Ki3, Ki11, and CML228, showed highly resistant (HR) or resistant (R) in spring and moderately resistant (MR) in fall. These three lines were already known as resistant inbred lines against downy mildew disease. It appears that spreader row technique was suitable for selection of maize downy mildew resistance in Cambodia. The incidence of downy mildew was influenced by weather conditions, especially relative humidity and temperature. Among several inoculation methods to screen for downy mildew resistance, this spreader row technique is effectively and easily used in the field of Southeast Asia.

Drought stress has detrimental effects on the seedling development, vegetative/ reproductive growth, photosynthesis, root proliferation, anthesis, anthesis-silking interval (ASI), pollination and grain yield in maize. Typically, two weeks before silking through pollination are an important time in maize life. Here we reviewed the effects of drought stress on growth, physiological/ molecular researches for drought tolerance, and breeding to genomics in maize. Drought stress during kernel development increases leaf dying and lodging, decreases grain filling period and grain yield. Physiological factors of drought stress/ effects are water content, water deficits, and water potential. Nowdays molecular marker assisted breeding method is becoming increasingly useful in the improvement of new germplasm with drought stress tolerance.

This study was carried out to investigate the effects of Salvia plebeia R. Br. ethanolic extract with differentaspects (stem/leaf and whole plant) on differentiation and lipid accumulation in 3T3-L1 preadipocytes. The morphologicalchanges and the degrees of lipid accumulation in 3T3-L1 cells were measured by Oil Red O staining and intra-cellular trig-lyceride (TG) assay. The mRNA expressions of special peroxisome proliferation activated receptor- genes (PPAR), CCAAT/enhancer-binding protein (C/EBPα), fatty acid synthase (FAS) and lipoprotein lipase (LPL) were detected by reverse tran-scriptase polymerase chain reaction (RT-PCR). The 50% ethanolic extracts (100μg/mL) of stem and leaf (SALE) and 30%ethanolic extracts (100g/mL) of whole plant (SAE) from Salvia plebeia R. Br. were significantly attenuated lipid accumula-tion during adipogenesis in 3T3-L1 cells. Ethyl acetate-soluble fractions (50μg/mL) significantly inhibited lipid dropletaccumulation in 3T3-L1 cells. In addition, SALE induced down-regulation of specific adipogenic transcriptional factors (C/EBPα and PPARγ) and target genes (FAS and LPL) during adipogenesis. Salvia plebeia R. Br. may be used as a safe and effi-cient natural substance to manage obesity.

The objective of this study was to evaluate the drought tolerance in maize seedling using leaf rolling. Nineteen maize resources, seven Nested Association Mapping parents lines, six Korean commercial cultivars, and six Southeast Asia commercial cultivars, were used to examine drought tolerance. The leaf rolling scores were measured on each leaf in three stress conditions with moderate drought (10%), severe drought (7%), and extreme drought (5%). Generally leaf rolling score of seedlings increased at the lower soil water potentials (5~7%). As a result, drought-tolerant cultivars showed lower leaf rolling score (below 2.5) than the drought sensitive cultivars (above 3.5). Nine varieties, NK4043, CML322, DK9955, NK4300, Ki11, DK8868, CML228, LVN99, and LVN10, have been selected for tolerance to drought stress. These results suggest that the leaf rolling score in maize seedling has been made available to indirect index for drought tolerance.

Maize is one of the most important food and feed crops in the world including Southeast Asia. In spite of numberous efforts with conventional breeding, the maize productions remain low and the loss of yields by drought and downy mildew are still severe in Asia. Genetic improvement of maize has been performed with molecular marker and genetic engineering. Because maize is one of the most widely studied crop for its own genome and has tremendous diversity and variant, maize is considered as a forefront crop in development and estimation of molecular markers for agricultural useful trait in genetics and breeding. Using QTL (Quantitative Trait Loci) and MAS (Marker Assisted Breeding), molecular breeders are able to accelerate the development of drought tolerance or downy mildew resistance maize genotype. The present paper overviews QTL/MAS approaches towards improvement of maize production against drought and downy mildew. We also discuss here the trends and importance of molecular marker and mapping population in maize breeding.

2000년부터 10년에 걸쳐 국내에서 총 5차례의 구제역이 발발하였다. 특히, 지난 2010년에 발생한 구제역은 전국적으로 약 340만 마리의 가축을 살처분 후 매몰하여 처분하였다. 가축 사체를 매몰하는 경우 매몰 초기에는 매몰지 내 산소를 이용하여 유기물을 분해하는 호기성 분해단계를 거쳐 잔류 산소가 소모된다. 매몰지의 경우 사체의 유기물로 인해 산소의 소모가 급격하게 이루어진다. 자연적 또는 인위적으로 산소를 유입하지 않는 경우 혐기성 상태로 치환되며 장기간 유지한다. 국내의 경우 2010년에 발생한 구제역으로 전국적으로 4,000여개소 이상의 매몰지가 조성되었으며 매몰지의 규모 및 매몰 두수는 지역별로 상이하다. 구제역 긴급행동지침에 따르면 500 m3 규모의 적정 매몰 두수는 돼지 550두로 제시되어 있다. 그러나 매몰지 내 유기물의 경우 일반적으로 고농도로 존재하는 것으로 나타났다. 따라서, 본 연구에서는 혐기성 생분해도 실험인 BMP(Biochemical Methane Potential) assay를 통해 매몰지내 유기물 농도에 따른 생분해도 특성을 평가하였다. 기질은 돈육을 이용하였으며 기질의 농도에 따른 최종 메탄 수율, 최대 메탄 발생율 및 저해 특성을 평가하였다. 또한, 원소분석을 통해 기질의 농도에 따른 생분해도를 평가하였다. 비선형 저해 방정식을 이용하여 기질 농도에 대한 저해 영향을 평가한 결과에 따르면 생분해도 및 최종 메탄 수율에 비해 상대적으로 최대 메탄 발생율이 민감하게 반응한 것으로 나타났다.

This research study was to develop methods for inhibiting the germination of cotton seeds. Germination rates after heating treatment at 80℃ with 10, 20, 30, 40 min. were 9.3, 9.3, 5.3 and 1.3 percentage, respectively. Heat treatment over 85℃ with 10 min. caused no germination of cotton seeds. Germination was significantly reduced with gamma rays treatment more than 10,000 gy, while the treatment within 2,000-8,000 gy induced less effects. Microwave processing for 30 seconds and 60 seconds inhibit the germination of cotton seed under 8 and 0%, respectively. As a physical treatment, rollmill milling with 1.5, 2, 2.5 mm gap inhibited any germination of cotton seeds. The optimum gap of roll-mill for processing physical cracking was below 51% of the thickness of seed.

The purpose of this study is to evaluate and to predict of eutrophication in lakes by using Vollenweider- OECD model and total phosphorus concentration and inflow rate which were measurded in 1993～2001. The results of study were as follows. The annual total phosphorus loading from the watershed was calculated to be 55～195tP/yr at lake Soyang, 221～466tP/yr at lake Taechong, 123～278tP/yr at lake Andong, 57～109tP/yr at lake Seomjin. These are discharged, for the most parts, from population and fishfarm facility. TP loading on the surface area at lake Soyang was 3.01gP/㎡/yr, 2.82gP/㎡/yr, 2.84gP/㎡/yr, 3.03gP/㎡/yr, 2.34gP/㎡/yr, 1.78gP/㎡/yr, 0.91gP/㎡/yr, 0.89gP/㎡/yr, 0.86gP/㎡/yr, lake Taechong was 6.71gP/㎡/yr, 7.25gP/㎡/yr, 7.24gP/㎡/yr, 6.53gP/㎡/yr, 6.50gP/㎡/yr, 7.06gP/㎡/yr, 7.04gP/㎡/yr, 4.05gP/㎡/yr, 3.44gP/㎡/yr and TP loading on the surface area of lake Andong, lake Soemjin were 5.39gP/㎡/yr, 4.47gP/㎡/yr, 4.56gP/㎡/yr, 4.45gP/㎡/yr, 3.33gP/㎡/yr, 2.38gP/㎡/yr, 2.53gP/㎡/yr, 2.46gP/㎡/yr, 2.54gP/㎡/yr, 4.09gP/㎡/yr, 4.10gP/㎡/yr, 3.98gP/㎡/yr, 3.73gP/㎡/yr, 2.80gP/㎡/yr, 3.46gP/㎡/yr, 3.22gP/㎡/yr, 2.19gP/㎡/yr, 2.13gP/㎡/yr respectively. The tropic states of four lakes can be assessed as eutrophy because phosphorus loading exceeds the critical phosphorus loading by Vollenweider-OECD model.

This study was performed to improve water demand estimation and analize correlation between generation of domestic sewage and domestic water use. To improve the prediction of water demand estimation, new water demand equation was developed. The results is as follows. InQt = β0 + β₁InPt + β₂InYt + β₃InHt + εt By using the statistical analysis of the "generation of domestic sewage" and "domestic water use", the regression equation between them is formed. The result is as follows. ＿ Generation of domestic sewage = 0.8487 × Domestic water use + 684.57 (R² = 0.972)

The purpose of this study is to evaluate and to predict of eutrophication in lakes by using Vollenweider-OECD model and total phosphorus concentration and inflow rate which were measurded in 1993-1996. The results of study was as follows. The annual total phosphorus loading from the watershed was calculated to be 181∼195tP/yr at lake Soyang, 591∼680tP/yr at lake Chungju, 420∼466tP/yr at lake Taechong, 229∼278tP/yr at lake Andong, 103∼106tP/yr at lake Hapchon, 57∼59tP/yr at lake Imha, 194∼244tP/yr at lake Namgang, 83∼86tP/yr at lake Chuam, 99∼109tP/yr at lake Somjin. These are discharged, for the most parts, from population and fishfarm facility. TP loading on the surface area at lake Soyang was 3.01gP/㎡/yr, 2.82gP/㎡/yr, 2.84gP/㎡/yr. 3.03gP/㎡/yr, at lake Chungju 7.9lgP/㎡/yr, 6.87gP/㎡/yr, 7.38gP/㎡/yr, 7.18gP/㎡/yr, at lake Taechong 6.7lgP/㎡/yr, 7.25gP/㎡/yr, 7.24gP/㎡/yr, 6.53gP/㎡/yr and TP loading on the surface area of Nakdong river basin, that is, lake Andong, Imha, Hapchon and Namgang were 5.39gP/㎡/yr, 4.47gP/㎡/yr, 4.56gP/㎡/yr, 4.45gP/㎡/yr and 2.20gP/㎡/yr, 2.23gP/㎡/yr, 2.24gP/㎡/yr, 2.17gP/㎡/yr and 4.50gP/㎡/ yr, 4.50gP/㎡/yr, 4.54gP/㎡/yr, 4.43gP/㎡/yr and 8.25gP/㎡/yr, 8.48gP/㎡/yr, 8.48gP/㎡/yr, 10. 39gP/㎡/yr respectively. Also those of lake Chuam was 2.51gP/㎡/yr, 2.61gP/㎡/yr, 2.52gP/㎡/yr, 2.54gP/㎡/yr and TP loading on the surface area at lake Somjin was analysed 4.09gP/㎡ /yr, 4.10gP/㎡/yr, 3.98gP/㎡/yr, 3.73gP/㎡/yr. The tropic states of nine lakes can be assessed as eutrophy because phosphorus loading exceeds the critical phosphorus loading by Vollenweider-OECD model.