• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.398-406
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• 2013

For the maximal production of aphicidal metabolites produced by the Beauveria bassiana Bb08, statistical methods such as the Box-Behnken experimental design and response surface methodology were used. The fungal culture filtrate was sprayed towards 3-star aphids and the mortality was examined. After the statistical analysis of the aphid mortality, the optimal culture conditions were found to be a culture temperature of $26.2^{\circ}C$, medium pH 5.9, flask shaking speed of 209.0 rpm, and culture time of 5.9 days. The expected mortality on days 4, 5, and 6 after spraying the filtrate on to the aphids were 76.8%, 84.9%, and 89.4%, respectively. All 4 factors of the culture conditions significantly affected the production of the aphicidal metabolites, and the order of significance was temperature, pH, culture time and shaking speed.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.123-123
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• 2003

야채 soup mix의 제조조건이 야채죽의 물리적 및 관능적 특성에 대한 영향을 조사하였다. Soup mix의 제조조건인 주입액의 양 (쌀 무게에 대한 물의 체적 비), 버섯, 당근 그리고 대파의 첨가량(쌀 무게에 대한 잣의 무게 비)에 따른 물리적 특성과 관능적 특성의 변화를 모니터링 하고자 반응 표면분석법 (response surface methodology, RSM)을 사용하였으며, 이때 실험계획은 중심합성계획법을 적용하였다. 요인변수(Xn)를 중심합성계획에 따라 17실험구로 구분하여 조리실험을 실시하였고, 이들 요인변수에 의해 영향을 받는 반응변수(Yn)는 야채죽의 물리적 특성으로 하여 회귀분석에 사용하였다. 회귀분석에 의한 모델식의 예측에는 SAS (statistical analysis system) program을 사용하였으며, 야채죽의 조리조건이 물리적 및 관능적 특성에 미치는 영향은 SAS program을 이용한 3차원 반응표면분석법으로 해석하였다. 야채의 배합비를 달리한 야채죽의 물리적 특성인 색도 L, a 및 b값에 대한 F-value는 자각 1.50, 11.75 및 5.58이고,유의수준이 각각 0.3044, 0.0019와 0.0169로서 a값과 b값의 유의성이 1% 수준에서 인정되어 이들 제조조건이 a값과 b값에 큰 영향을 미치는 것으로 나타났다. 점도와 퍼짐성에 대한 유의수준은 각각 0.6920과 0.7528이고, 반응표면회귀식의 $R^2$은 각각 0.4766과 0.4436으로 유의성이 인정되지 않았다. 고형분에 대한 유의수준은 0.2026이고 회귀식의 $R^2$는 0.7107으로서 버섯, 당근 및 대파 첨가량이 고형분의 변화에 영향을 미치지 않은 것을 알 수 있었다. 관능적 특성인 색상에 대하여 soup mix의 제조조건이 야채죽에 미치는 영향은 F-value는 6.23이고, 유의수준이 0.0124으로서 1%수준에서 유의성이 인정되었으며, 회귀식의 $R^2$은 0.8890이다. 향에 대한 유의확률은 0.4555이고 0.05이상이므로 유의성이 인정되지 않아 설정된 범위내에서 야채죽의 향에 대하여 크게 영향을 미치지 않는 것으로 나타났다. 점성에 대한 반응표면회귀식의 $R^2$은 0.8134로서 그 유의성이 5%수준에서 인정되었다. 맛과 전반적 기호도에 대하여 야채의 배합비에 따른 반응표면회귀식의 $R^2$은 각각 0.7374와 0.8651이며, 유의화률은 0.1578과 0.0228으로 나타나 전반적인 기호도에 대한 영향은 10% 유의수준에서 영향을 주었다. 결론적으로, 물리적 특성인 색도, 점성, 퍼짐성과 고형분의 함량은 관능적 특성인 색과 비교적 높은 정(正)의 상관을 나타내었으며, 관능적 특성인 향과의 상관은 유의성이 인정되지 않았다. 야채죽 제조를 위한 soup mix의 제조조건에 있어서 야채의 배합비는 색과 점성에 영향을 미치는 가장 주요한 조건이라고 생각된다.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.567-586
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• 2011

The purpose of this study was to investigate the gifted students' view on argumentation and the aspects of the argumentation in problem-solving type experiment. As a result, very lively argumentation was identified but quality enhancement on argumentation wasn't found over time. Students made frequent use of dialogic argumentation component, and especially, request & response component was highly used. Though usage frequency is low, the component of ground & question on ground was shown in 3rd class, and simple agreement gradually reduced, and reinforcing elaboration & metacognitive question has slightly increased. Also, students' argumentation were closely related to teachers' teaching approaches as some teacher-led steps doesn't appear in students' argumentation. By comparison in steps, 'problem solving activity & result analysis' step included 2 times more argument components than the previous step. We also found that method grouping teams does not almost affect the argumentation of gifted students. By survey results, most students recognized that they experienced free argumentation and this program activate argumentation and 'strange things' or 'difficulty' of program topics are obstacles in vitalization of argumentation. 'Surface growth experiments' was the most lively argumentation topic. The argumentation was lively made in the step of 'finding solution. 'Teachers' scaffolding accelerate the argumentation and help resolve difficulties in argumentation. Thus, students have positive recognition for the argumentation process in the experiments and recognize that argumentation process is needed.

• Smart Structures and Systems
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• v.21 no.5
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• pp.623-635
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• 2018

In order to study the mechanical behavior of shield tunnel segments during assembly stage, the in-situ tests and FDM numerical simulation were conducted based on the Foguan Shiziyang Tunnel with large cross-section. Analysis for the load state of the assembling segments in different assembly steps as well as the investigation for the changing of inner forces and longitudinal stress of segments with assembling steps were carried out in this paper. By comparing the tested results with the simulated results, the conclusions and suggestions could be drawn as follows: (1) It is the most significant for the effects on axial force and bending moment caused by the assembly of adjacent segment, followed by the insertion of key segment while the effects in the other assembly steps are relative smaller. With the increasing value of axial force, the negative bending moment turns into positive and remains increasing in most monitored sections, while the bending moment of segment B1and B6 are negative and keeping increasing; (2) The closer the monitored section to the adjacent segments or the key segment, the more significant the internal forces response, and the monitored effects of key segment insertion are more obvious than that of calculation; (3) The axial forces are all in compression during assembling and the monitored values are about 1.5~1.75 times larger than the calculated values, and the monitored values of bending moment are about 2 times the numerical calculation. The bending moment is more sensitive to the segments assembly process compared with axial force, and it will result in the large bending moment of segments during assembling when the construction parameters are not suitable or the assembly error is too large. However, the internal forces in assembly stage are less than those in normal service stage; (4) The distribution of longitudinal stress has strong influence on the changing of the internal forces. The segment side surface and intrados in the middle of two adjacent jacks are the crack-sensitive positions in the early assembly stage, and subsequently segment corners far away from the jacks become the crack-sensitive parts either.

• Journal of the Korean Society of Food Culture
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• v.17 no.5
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• pp.653-662
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• 2002

Korean native Perilla Jangachi (salted and fermented vegetable) is popular and well-known but little study on its composition and most palatable condition has been reported. This study was performed to observe the change in the contents of chemical components and sensory evaluation of Perilla Jangachi which was prepared through two processing. First, as a pretreatment, Perilla leaves were soaked in salt water. The optimal level of salt concentration and soaking time (salt 4%, soaking time 42hours) was determined. Second, soaked Perilla Jangachi was steamed and then fermented in various ingredients like soy sauce, sugar, onion and so on. In this study, Perilla Jangachi was made by 3 levels of steaming time(30 seconds, 60 seconds, 90 seconds) and onion contents (10%, 30%, 50%). The optimal level of onion contents and steaming time was determined with the results of sensory evaluation by response surface methodology and analysis of composition. Sodium contents were decreased as the levels of onion contents were increased. Flavonoids contents weren't increased although contents of onion were increased. But they were influenced on steaming time that as the levels of steaming time were shortened, flavonoids contents were increased. To lengthen the shelf-life of Perilla Jangachi, the activities of enzyme peroxidase - which changes Jangachi's quality bad - by various levels of steaming time were measured. After steaming 50 seconds, peroxidase became inactive. Reducing sugar contents were decreased relying on either increased steaming time and onion contents. While steaming 30 seconds and 10% onion contents, the content of reducing sugar was 0.858% but steaming 90 seconds and 50% onion contents, it became 0.372%. Among the sensory attributes, brownness was increased as onion contents increased and steaming more than 60 seconds. Saltiness, sweetness, perilla flavor were greater relying on decreased onion contents. Toughness was decreased as both the amounts of onion and steaming time were increased. With this results, the most optimal adding level of onion content and steaming time was determined. Steaming 72 seconds and adding onion 27% was established as a optimal condition of Perilla Jangachi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.733-739
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• 2014

To develop an effective use for poor-quality individually quick-frozen (IQF) oysters Crassostrea gigas stored for a long period, the extract conditions, quality characteristics, and optimum reaction flavoring (RF) conditions of a complex extract from these IQF oysters were investigated. The moisture, pH, and volatile basic nitrogen contents of IQF oysters stored for 18 months (18M-IQFO) were 77.9%, 6.32, and 17.9 mg/100 g, respectively. Three different kinds of extract were prepared from 18M-IQFO: a hot-water extract (HE), scrap enzymatic hydrolysate (EH), and complex extract (CE). The respective extracts contained 5.5, 8.6, and 6.6% crude protein and 281.7, 366.0, and 343.0 mg/100 g amino nitrogen, and had 811, 359, and 1,170 mL/kg extraction yields. The CE was superior to the traditional HE in terms of the extraction yield, amino-nitrogen content, and organoleptic qualities, except for the odor. To improve flavor via the Maillard reaction, the reaction system used to produce a desirable flavor comprised CE (Brix $30^{\circ}$), 0.4 M glucose, 0.4 M glycine, and 0.4 M cysteine solution (4:2:1:1, v/v). The reaction time and pH were the independent variables, and the sensory scores for baked potato odor, masking shellfish odor, and boiled meat odor were the dependent variables. The surface response methodology (RSM) analysis of the multiple responses optimization gave a reaction time of 120.6 minutes and pH 7.33 at $120^{\circ}C$. The reaction improved the flavor of CE considerably, as compared to that of the unreacted extract.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.253-262
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• 2016

Yeonsan Ogae has been known as supporting health and high efficacy of treatment. In recent days, as the efficacy of functional peptides has known, the optimization of oligo peptides production and its characteristics from Ogae viscera has been performed. Response surface method was used to perform the optimizaion of enzyme hydrolysis. The range of processes was temperature (40, 50 and $60^{\circ}C$), pH(6.0, 7.0 and 8.0), and enzyme(1, 2 and 3%). The degree of hydrolysis, amono acids, molecular weight of products were analyzed. The optimum process of enzyme hydrolysis were determined as temperature $58^{\circ}C$, pH 7.5, and enzyme concetration 3%. At optimum conditions, the degree of hydrolysis after 2 h reaction was 75-80%. The total amino acids of amino acid and were 386.15 mg/100 g and 155.26 mg/100 g, respectively. The molecular weight of products by using Maldi-TOF was ranged from 300 to 1,000 Da.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1012-1017
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• 2005

Predictive growth model of putrefactive bacteria of surimi-based imitation crab in the modified surimi-based imitation crab (MIC) broth was investigated. The growth curves of putrefactive bacteria were obtained by measuring cell number in MIC broth under different conditions (Initial cell number, $1.0{\times}10^2,\;1.0{\times}10^3$ and $1.0{\times}10^4$ colony forming unit (CFU)/mL; temperature, $15^{\circ}C,\;20^{\circ}C\;and\;25^{\circ}C$) and applied them to Gompertz model. The microbial growth indicators, maximum specific growth rate constant (k), lag time (LT) and generation time (GT), were calculated from Gompertz model. Maximum specific growth rate (k) of putrefactive bacteria was become fast with rising temperature and fastest at $25^{\circ}C$. LT and GT were become short with rising temperature and shortest at $25^{\circ}C$. There were not significant differences in k, LT and GT by initial cell number (p>0.05). Polynomial model, $k=-0.2160+0.0241T-0.0199A_0$, and square root model, $\sqrt{k}=0.02669$ (T-3.5689), were developed to express the combination effects of temperature and initial cell number, The relative coefficient of experimental k and predicted k of polynomial model was 0.87 from response surface model. The relative coefficient of experimental k and predicted k of square root model was 0.88. From above results, we found that the growth of putrefactive bacteria was mainly affected by temperature and the square root model was more credible than the polynomial model for the prediction of the growth of putrefactive bacteria.

• Food Science and Preservation
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• v.14 no.5
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• pp.474-480
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• 2007

Response surface methodology (RSM) was employed to optimize extraction conditions preserving valuable functional properties of fluid Cheonggukjang obtained from red ginseng. Based on a central composite design, the study plan was established using variations in microwave power, ethanol concentration, and extraction time. Regression analysis was applied to obtain a mathematical model. A maximum electron donating ability (EDA) of 99.09% was obtained under the specific extraction conditions of microwave power 135.62 W, ratio of solvent to sample contents. 3.60 g/mL, and an extraction time of 11.79 min. The maximum inhibitory effect on tyrosinase activity was 10.02% at 119.16 W, 4.02 g/mL, and 5.57 min. The maximum superoxide dismutase (SOD)-like activity was 63.83% under the extraction conditions of 125.29 W, 4.04 g/mL, and 11.02 min. Based on superposition of four-dimensional RSM data obtained to optimize electron donating ability, nitrite-scavenging ability, inhibitory effect on tyrosinase activity, and SOD-like activity, the optimum ranges of extraction conditions were found to be a microwave power of $l{\sim}85 W$, a ratio of solvent to sample content of $1.4{\sim}2.8\;g/mL$, and an extraction time of $6.5{\sim}11\;min$.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.117-124
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• 2005

Recently the first stage of construction for Busan new port emerged over the sea surface at the north container terminal site. With this, there are lot of discussions and debates on increasing the water depth at the approaching channel and mooring basin from the existing 15m to 18m by dredging work in order to be able to serve 12,000TEU containership, and at the same time, correction to the reclamation plan of hinterland at the part of Undong Bay of the new port site. Since the attack of typhoon 'Maemi' in 2003, it is expected that the design wave parameters for coastal and harbor structures in this area would be somewhat changed and so the extreme wave condition at each terminal and tranquility of berthing area does, and therefore, it is necessary to analyze the tranquility at each berth. Hence in this study, we constructed a wave model for these conditions and performed simulation together with the circulation model simulation, compared with the field data collected. The result showed the increase of the harbor response throughout the basin but not severe condition. However, a certain location needs to be prepared for the rough sea condition when a severe typhoon hit the site.