본 논문에서는 빙하가 녹아 갈라져서 떠내려 온 새끼 펭귄이 다시 펭귄 무리로 되돌아가기 위 해서 길을 찾아 나서는 퍼즐 어드벤처 게임을 제안한다. 플레이어 40명의 로그 기록과 설문지 를 분석한 결과를 바탕으로 제안하는 게임의 특징을 살펴보고자 한다. 첫째, 제안하는 게임은 새끼 펭귄이 얼음 덩어리를 밀어서 길을 만들어 이동하는 직관적인 규칙을 제공한다. 로그 기 록에서 플레이 평균 시간은 19분이며, 이를 19개의 리스폰 지점으로 나누면, 구간별 플레이 평균시간은 1분이다. 설문에서 게임 목표 명확성은 4.45점, 게임 난이도는 4.16점을 받았다. 둘째, 제안하는 게임은 가마우지가 새끼 펭귄에게 도움말을 제시하는 등 유용한 정보를 친절 하게 제공한다. 전체 플레이 평균 시간은 baseline이 24분이고, kinder UI가 19분이다. kinder UI에서 새끼 펭귄이 얼음 덩어리를 덜 밀고, 게임 재시작을 덜 하고, 더 빨리 상호작 용하여, 문제를 빨리 해결한다. 설문에서 게임 스토리 이해는 4.15점, 유용한 정보는 4.45점을 받았다. 셋째, 제안하는 게임은 남극과 유사한 환경을 제공하여 몰입도를 상승시킨다. baseline에 비해서 kinder UI에서 다양한 게임 오브젝트와 더 적극적으로 상호작용을 시도하 고, 미션 완료 후 더 오랫동안 오로라를 지켜봤다. 설문에서 게임 캐릭터 선호도는 4.56점, 게 임 환경 만족도는 4.22점을 받았다.

The development of biochemical pesticides to replace existing chemical pesticides and the search for new substances with potential insecticidal ability are continuously required. The purpose of this study is to control myzus persicae with pyrethrum biochemical pesticide containing of high concentration of pyrethrin as an active ingredient. Pyrethrum dried powder was extracted with 95% ethanol for different periods of time and it was confirmed that the pyrethrin content increased as the extraction period increased and the extraction conditions for 20 days had the highest yield with 0.2% pyrethrin. We produced a prototype containing 0.13% pyrethrin content (pyrethrin II: 0.06%, pyrethrin I: 0.06%). and in 200 fold dilute spray condition. It showed a 77.2% corrected mortality against myzus persicae which is comparable to chemical pesticide. We are continuously researching to reduce the decomposition of active ingredients and look for additives to increase the insecticidal activity.

PURPOSES: The objective of this study is to evaluate the application of soil stabilization method for soft shoulder construction in the iRoad Project of Sri Lanka. METHODS: Firstly, the quantitative analysis of soil strength improvement due to soil stabilization was done for soil samples collected from iRoad construction sites. Two types of soils were selected from iRoad Project sites and prepared for soil stabilization testing by the Road Development Authority. Secondly, the appropriate stabilizer was selected at given soil type based on test results. Two different stabilizers, ST-1 and ST-2, produced in Korea were used for estimating soil strength improvements. Finally, the optimum stabilizer content was determined for improving shoulder performance. The uniaxial compressive strength (UCS) test was conducted to evaluate the strength of stabilized soil samples in accordance with ASTM D 1633. The use of bottom ash as a stabilizer produced from power plant in Sri Lanka was also reviewed in this task. RESULTS: It is found from the UCS testing that a 3% use of soil stabilizer can improve the strength up to 2~5 times in stabilized soft shoulder soils with respect to unstabilized soils. It is also observed from UCS testing that the ST-1 shows high strength improvement in 3% of stabilizer content but the strength improvement rate with increase of stabilizer content is relatively low compared with ST-2. The ST-2 shows a low UCS value at 3% of content but the UCS values increase significantly with increase of stabilizer content. When using the ST-2 as stabilizing agent, the 5% is recommended as minimum content based on UCS testing results. Based on the testing results for bottom ash replacement, the stabilized sample with bottom ash shows the low strength value. CONCLUSIONS: This paper is intended to check the feasibility for use the soil stabilization technique for shoulder construction in Sri Lanka. The use of soil stabilizer enables to improve the durability and strength in soft shoulder materials. When applying the bottom ash as a soil stabilizer, various testings should be conducted to satisfy the specification criteria.

In Sri Lanka, the shoulder in asphalt pavements has been constructed using the materials transported from borrow pit in the iRoad Project due to the low quality of in-situ soils. After excavating 150~200mm thick and 500mm wide shoulder area, the borrow pit materials are placed and compacted according to specifications. The excavated in-situ soils are dumped in designated location. It is estimated that this process of shoulder construction is not economical due to high material transportation cost and can also induce the environmental issues by disposal of in-situ soils. It can also cause distresses such as surface rutting and edge drop-off in soft shoulder section due to bearing capacity failure and off-tracking of vehicle. The heavy rainfall in Sri Lanka can induce severe erosion problem when using the soft shoulder. To improve the strength and durability of pavement shoulders in the iRoad Project, the soil stabilization will be a good alternative to solve the above mentioned problems. The use of in-situ soils with addition of soil stabilizer enables to reduce the construction cost of shoulder section and mitigate the environment issues. The objective of this task is to review the application of soil stabilization method for soft shoulder construction in the iRoad Project. Firstly, the quantitative analysis of soil strength improvement due to soil stabilization was done for soil samples collected from iRoad construction sites. Two types of soils were selected from iRoad Project sites and prepared for soil stabilization testing by the Road Development Authority. Secondly, the appropriate stabilizer was selected at given soil type based on test results. Three different stabilizers, ST-1, ST-2, and ST-3, produced in Korea were used for estimating soil strength improvements. Finally, the optimum stabilizer content was determined for improving shoulder performance. The uniaxial compressive strength (UCS) test was conducted to evaluate the strength of stabilized soil samples in accordance with ASTM D 1633. The use of bottom ash as a stabilizer produced from power plant in Sri Lanka was also reviewed in this task.

Ohmic heating is one of advanced thermal processing techniques which utilize conversion of electrical energy into heat. In our study, a feasibility of ohmic heating was tested to cook instant rice cake to improve energy efficacy as an alternative heating methods of conventional electrical kettle. Ohmic heating was conducted using customized ohmic cell (7.5×4.5×9.5 cm) equipped with titanium electrodes. Instant rice cakes in soup were ohmically heated up to 100°C at different electric fields (9, 12, 15 & 18 V/cm) and temperature holding times (60, 80, 100 & 120 s). Thermocouple was placed into both soup and rice cake to evaluate the temperature profile and energy efficacy. Temperature, voltage and current across the sample were measured and recorded at every 3 s using data acquisition system (DAQ). Mathematical model was developed to calculate the internal energy generation rate (QR, W). Internal energy generation rate (QR, W) was integrated versus temperature come-up time (s) to compute the total internal energy dose (ET, J) using MATLBA software. For energy efficacy (Eff), it was calculated ratio of total internal energy dose (ET, J) to heat quantity (Qh, J). During ohmic heating, temperature come-up time was significantly reduced as a function of elevated electric field (P<0.05). For example, 9V/cm of electric field showed 6.2±0.4 min of temperature come-up time up to 100°C. Higher electric field at 18 V/cm reduced temperature come-up time to 1.9±0.1 min. The electric field of 15 V/cm showed the best energy efficacy as 0.78 which meant 78% of electrical energy was converted into thermal energy for heating. In the texture profile analysis, the most preferable harness was found as 6.191 N at 15 V/cm and 100 s holding time. Our study showed the potential of ohmic heating to cook instant rice cakes for home meal replacement (HMR) and outdoor foods.