User churn in games often arises due to inadequate game difficulty. To address this, non-player characters (NPCs) has been utilized to modulate difficulty according to individual game skill. Nevertheless, the effectiveness of solely NPC-based adjustments is limited since game difficulty is influenced by both NPCs and environmental factors. This paper introduces a novel method for dynamically tailoring game difficulty by adjusting in-game environments based on player behavior patterns in top-down shooter game. Through analysis of diverse user game play data, we find that factors within the game environment, such as the distribution of enemy characters and the arrangement of terrain, have a substantial influence on the level of difficulty. Furthermore, it has been observed that behavioral patterns of players show variations according to changes in the game environment. Using these analytical result, we devise an artificial neural network model that configures an environment that suit player behavior patterns. With the model, we figure out the user player pattern and control the difficulty dynamically by changing the environment factors. Through the experiments, we show that our method provides an appropriate level of difficulty for users to prevent user churn.

Alfalfa is one of the most useful forage crops worldwide, containing a high level of amino acids that are essential to both human and animal health. However, amino acids and their concentrations may differ between plant parts. Hence, detecting amino acids in different plant parts would be useful in the development of diet supplements. The purpose of this study was to determine the amino acid content in alfalfa leaves, stems, and inflorescences using an amino acid analyzer. Asparagine and glutamic acid were the most abundant amino acids found in stems, leaves, and inflorescences than other amino acids. All parts of alfalfa had low concentrations of cysteine and methionine. All amino acids except asparagine were present in the highest concentration in leaves followed by inflorescences. Leaf had a rich amino acid content, namely asparagine, glutamic acid, leucine, proline, and lysine. However, the stem had a lower amino acid composition than the leaf or inflorescence. Overall, the data showed determining the amino acid content of forages provides a good approach to making animal feed with essential and specific amino acids and preventing excessive inclusion of amino acids.

After the permanent shutdown of K1 in 2017, decommissioning processes have attracted great attention. According to the current decommissioning roadmap, the dismantling of the activated components of K1 may start in 2026, following the removal of its spent fuel. Since the reactor vessel (RV) and reactor vessel internal (RVI) of K1 contain massive components and are relatively highly activated, their decommissioning process should be conducted carefully in terms of radiological and industrial safety. For achieving maximum efficiency of nuclear waste management processes for K1, we present activation analysis of the segmentation process and waste classification of the RV and RVI components of K1. For RVI, the active fuel regions and some parts of the upper and lower active regions are classified as intermediate-level waste (ILW), while other components are classified as low-level waste (LLW). Due to the RVI’s complex structure and high activation, we suggest various underwater segmentation techniques which are expected to reduce radiation exposure and generate approximately nine ILW and nineteen very low level waste (VLLW)/LLW packages. For RV, the active fuel region and other components are classified as LLW, VLLW, and clearance waste (CW). In this case, we suggest in-situ remote segmentation in air, which is expected to generate approximately forty-two VLLW/LLW packages.

This study was conducted to investigate the effects of Kojongsi persimmon peels as a mushroom substrate on antioxidant activity of Pleurotus eryngii. The Pleurotus eryngii was growth on the medium with 0, 5, 10, 15, 20, 30, 40, 50% Kojongsi persimmon peels. The Pleurotus eryngii was extracted into ethanol and their antioxidant activities were analyzed. The total polyphenol content was highest in the 20% Kojongsi persimmon peels treatment (40±0.38 mg of gallic acid equivalents/100 g) than 0% Kojongsi persimmon peels treatment (21 ±0.18 mg of gallic acid equivalents/100 g). The 20% Kojongsi persimmon peels treatment showed better DPPH scavenging activity (36.81±0.23% at 1 mg/ml), ABTS scavenging activity (39.03±0.10% at 1 mg/ml) and reducing power (0.3±0.10% at 1 mg/ml) than 0% Kojongsi persimmon peels treatment and another extract ones. Overall, total polyphenol content and antioxidant activities of extracts from Pleurotus eryngii was increased dose dependently and 20% Kojongsi persimmon peels treatment was showed better total polyphenol content and antioxidant activities than 0% Kojongsi persimmon peels treatment and another extract ones.

Bottom mushroom (Agaricus bisporus) is an edible basidiomycete mushroom in Europe and North America. The wheat straw, wheat brain and chicken manure were used for bottom mushroom cultivation. Bottom mushroom substrates for cultivation was collected from bottom mushroom farm in Buyeo. About 16 bacteria were isolated from fresh mushroom substrates on TSA medium. Among of the isolates, isolate 3HS12 possessed high cellulase and mannase activity was selected as a hydrolase-producing bacteria. The isolate 3HS12 was identified as members of the Bacillus subtilis by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that isolate 3HS12 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rDNA gene sequence similarity of 98.8%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, the 3HS12 isolate was assigned to the Bacillus subtilis. The cellulase and mannase activity of Bacillus subtilis 3HS12 was increased according to the bacterial density at 40°C.

The Kojongsi persimmon peels is byproduct after production of dried persimmon. This study was conducted to investigate optimal mixing ratio of Kojonsi persimmon peels as a substrate for cultivation of Pleurotus eryngii. The primary nutritive material of substrate for Pleurotus eryngii was corncob, soybean meal, beet pulp, ground corn and bran. Five to forty percent of persimmon peels were mixed with primary nutritive materials as new substrate. The chemical properties of substrate mixed with Kojongsi persimmon peels was similar to the mixture without Kojongsi persimmon peels in T-C, T-N, C/N ratio, and other nutrients. Mycelial growth time on medium with 5 to 30% persimmon peels was similar to the control without persimmon peels as 27 days but that on medium with 40% and 50% persimmon peels was delayed for 10 days. The time of pinhead formations in medium with 5 to 30% persimmon peels was 12 days, the growth time to harvest was 6 days. These results were similar to those of the control without persimmon peels. The sizes of pileus of treatments with 5 to 30% persimmon peels were tend to be smaller compared with the control. The length of stipe of 10% persimmon peels treatment was 80 mm which was shorter than that of the control with 120 mm.

Oxalic acid has a nematicidal activity against the root-knot nematode Meloidogyne incognita. High producer of oxalic acid was isolated, and then named as Aspergillus niger F22. Oxalic acid production was investigated under various temperatures from 20 – 33oC and rotational speeds in 5 L jar fermenters. Yield of oxalic acid increased with decreasing temperature. The highest yield was obtained at 23oC, showing the yield of oxalic acid of 8.7 g/L, whereas oxalic acid production was least at 33oC. At 20oC, the yield was lower than that of 23oC. At a rotational speed of 300 rpm, serious oxygen depletion was present from 48 - 72 h, resulting in low productivity of 26.2 mg /L·h. When a rotational speed was set at 600 rpm, dissolved oxygen tension was over 40% and oxalic acid production increased up to approximately 55%. Viscosity during the culture differed with temperatures. Viscosity increased with the increment of temperatures. When A. niger F22 was cultured at 23oC, viscosity was 810 cP, which was favorable for oxalic acid production.

A nematode, which showed entomopathogenicity, was isolated from Exomala orientalis in Korea, and then identified as Rhabditis blumi. Pathogenicity of R. blumi was evaluated against major cruciferous insect pests, including Artogeia rapae, Mamestra brassicae, and Plutella xylostella. In Petri-dish tests, insect mortality was dose and time dependent, which increased with dose (0–80 dauer juveniles/larva) and time increments. In greenhouse tests, P. xylostella larvae were most susceptible to nematodes, with insect reduction rate of 88.0 %. The rate varied with vegetable species and persistence time of live nematodes on vegetable leaves after spraying. The aeration rate was an important parameter for cultivation of the nematode R. blumi. A sufficient DOT level in the culture using an air-lift bioreactor should be maintained. The nematode growth rate increased with an increasing DOT level and/or bacteria uptake rate. The maximum nematode yield of 1.75 x 105 per ml was obtained under an aeration rate of 6 vvm.

The mannanase-producing bacteria, designated YJ17, was isolated from spent mushroom (Flammulina velutipes) substrates. The isolate YJ17 was a facultative anaerobic and was grown at temperatures ranging from 20oC to 50oC with an optimal temperature of 40oC. The DNA G+C content of the YJ17 was 44 mol%. The major fatty acids were anteiso-15:0 (38.9%), 17:0 (7.6%), and iso-15:0 (36.5%). The 16S rRNA gene sequence similarity between the isolate YJ17 and other Bacillus strains was from 98% to 99%. In the phylogenetic analysis based on these sequences, the isolate YJ17 and Bacillus amyloliquefaciens clustered within a group together and separated from other species of Bacillus. Based on the physiological and molecular properties, the isolate YJ17 was classified within the genus Bacillus as B. amyloliquefaciens YJ17. The optimal pH and temperature for mannanase activity of B. amyloliquefaciens YJ17 were pH 7.0 and 50oC, respectively.

This study was carried out to investigate optimal mixture of persimmon peels for Pleurotus eryngii cultivation. The 5-50% of persimmon peels was mixed with mushroom growing medium for Pleurotus eryngii cultivation. Mycelial growth of persimmon peels treatment were 74-165 mm (28 days) and slower than that of control (treatment without persimmon peels) as 160 mm (28 days). Mycelial growth time of 5-20% persimmon peels treatment were similar to control as 34 days but that 30-50% of persimmon peels treatment were delayed for 17 days. The time of pinhead formations in control and 5-50% persimmon peels treatment were 11 days, the growth time to harvest were 6-7 days. The sizes of pileus of 15% persimmon peels treatment was tend to be smaller compared with control. The length of stipe of 15% persimmon peels treatment was 124 mm which was longer than that of the control with 118 mm. The thickness of stipes of 15% persimmon peels treatments was 48 mm which were tend to be thicker than that of the control with 47 mm. Thirty percent of persimmon peels treatment was better than other treatment comparing with control.

This study was carried out to develope mushroom growing medium for Pleurotus eryngii cultivation using persimmon peels. Total nitrogen, carbon source and protein of commercial cultivation medium used in this study was 1.34, 53.9 and 0.09 %, respectively. The C/N ratio was 40.22. The total nitrogen was increased by increasing mixing ratio of persimmon peels. The carbon source and protein was no significant difference by increasing mixing ratio of persimmon peels. In column test, mycelial growth of 15% persimmon peels treatment was similar with control, but mycelia of 20-50% persimmon peels treatment was growed slowly compared with control. To investigate yields of fruiting body, 15% of persimmon peels was mixed with commercial cultivation medium. The fruiting body of 15% persimmon peels treatment was no significant difference yield compared with control. But, the chemical contents of 15% persimmon peels treatment were the higher than control.

True hermaphrodites are animals of equivocal sex in which both male and female gonads develop simultaneously. The frequency of true hermaphroditism is higher in pigs than in other domestic animals. Two Korean pigs were diagnosed with true hermaphroditism showing ovotestes, epididymes, penes, and uteri. Histomorphologically, the testicular tissues consisted of Sertoli cells that were devoid of spermatogenic germ cells and showed proliferation of interstitial cells. However, the uteri were of normal architecture and had well-developed uterine endometrial glands. The samples were 38, XX female karyotype without the sex-determining region Y (SRY) gene. The findings of this study could contribute to the understanding of true hermaphroditism in the Korean pig industry. * This work was supported by a grant (Code# PJ008148) from BioGreen21 Program, Rural Development Administration, Republic of Korea.

The toxicity of methanol extract from 28 plants toward four agricultural insect pests were examined using contact toxicity bioassay with spray methods. At a concentration of 1,000 ppm Achyranthes japonica whole body was observed strong activity against Myzus persicae. Paeonia lactiflora root and Corydalis turtschaninovii rhizome methanol extract were observed strong activity toward Tetranychus urticae. Catalpa ovata leaf and Ginkgo biloba leaf and stem methanol extracts were revealed high activity toward Nilaparvata lugens. Actium lap root methanol extract was observed moderate activity against Plutella xylostella. High or moderate insecticidal activity of plant extracts were listed in Fig.1. These plant resource, particularly plant methanol extract or insecticidal constituents, merit further as potential insect pest control agents or leads because of their great activity as a insecticide.

Root knot nematode species, such as Meloidogyne hapla, M. incognita, M. arenaria and M. javanica are economically most notorious nematode pests, causing serious damage to the various crops throughout world. In this study, DNA sequence analyses of the D1-D3 expansion segments of the 28S gene in the ribosomal DNA were conducted to characterize genetic variation of the four Meloidogyne species obtained from Korea and United States. PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism), SCAR (Sequence Characterized Amplified Region) marker and RAPD (Random Amplification of Polymorphic DNA) also were used to develop the methods for exact and rapid species identification. In the sequence analysis of the D1-D3 expansion segments, only a few nucleotide sequence variation were detected among M. incognita, M. arenaria, and M. javanica, except for M. hapla. The PCR-RFLP analysis that involves amplification of the mitochondrial COII and lrRNA region yielded one distinct amplicon for M. hapla at 500 bp, enabling us to distinguish M. hapla from M. incognita, M. arenaria, M. javanica reproduced by obligate mitotic parthenogenesis. SCAR markers successfully identified the four root knot nematode species tested. We are under development of RAPD primers specific to the three root knot nematodes found in Korea.

이 연구에서는 플라즈마 제염 기술의 실용화를 위해 , , 등의 반응성 플라즈마 기체를 이용하여 원자력 시설의 주요 오염원인 코발트 핵종에 대한 표면 제염 모의실험을 수행하였다. 디스크 형태의 금속코발트에 대하여 시편 표면 온도를 변수로 플라즈마 식각 실험을 수행한 결과 반응율은 에서 기체의 경우 그리고 와 기체의 경우 각각 과 이었으며, 이들 반응의 활성화에너지는 각각 39.4 kJ/mol, 42.1 kJ/mol, 116.0 kJ/mol이었다. 이와 함께 AES (Auger Electron Spectroscopy)를 이용하여 반응 생성물 성분 분석 결과 이들 반응의 주요 반응 기구는 코발트의 불화 반응임이 밝혀졌다. 이 연구를 통해 확보된 의 금속 표면 식각율은 주요 반도체 공정의 식각율을 뛰어넘는 높은 식각율로 플라즈마 제 염 기술의 실용화를 앞당길 수 있는 고무적인 결과라 할 수 있을 것이다.

연구로 2호기 해체과정에서 발생한 방사화된 수조 콘크리트 내의 깊이에 따른 및 의 방사능 분포를 고온연소로와 액체섬광계수기를 이용하여 분석하였다. 또한 향후 연구로 2호기 해체과정에서 발생된 콘크리트폐기물의 핵종재고량 평가에 활용하기 위하여 및 측정결과와 감마방출핵종과의 상관관계를 도출하였다. 및 의 검출하한값은 0.048 및 0.028 Bq/g이다. 연구로 2호기 수조 콘크리트 내의 및 의 깊이별 방사능 분포는 콘크리트 표면으로부터 멀어질수록 지수적으로 감소하는 경향을 보여주었다. 또한, 및 의 비방사능은 콘크리트에 존재하는 의 비방사능과 좋은 상관관계를 나타내었다.