Silage inoculants, which include beneficial microorganisms like lactic acid bacteria (LAB), play a vital role in modern silage production by enhancing fermentation quality. This study evaluated the effectiveness of various commercial inoculants on the fermentation dynamics of Italian ryegrass silage over 45 days. The treatments included a control group and five inoculant formulations: T1 (Lactiplantibacillus plantarum), T2 (Lactiplantibacillus plantarum and Pediococcus pentosaceus), T3 (Lactiplantibacillus plantarum and Pediococcus pentosaceus and Lactiplantibacillus buchneri), T4 (Lactiplantibacillus plantarum and Lactiplantibacillus acidophilus and Lactiplantibacillus bulgaricus), and T5 (Lactiplantibacillus plantarum and Pediococcus pentosaceus and Enterococcus faecium). After 45 days, all treatment groups exhibited significantly higher crude protein (CP) content compared to the control group (80.64 g/kg dry matter (DM), p<0.05). Treatments T2 and T5, which incorporated combinations of Lactiplantibacillus plantarum, Pediococcus pentosaceus and Enterococcus faecium, showed higher CP contents at 105.53 and 107.05 g/kg DM, respectively. The inoculated silages also demonstrated a rapid pH reduction within the early days, with Lactiplantibacillus plantarum in T1 reducing the pH to 4.0 within four days. Additionally, inoculated treatments had significantly higher lactic acid levels than the control (67.96 g/kg DM, p<0.05), and T3 (Lactiplantibacillus buchneri) produced higher acetic acid levels (16.07 g/kg DM, p<0.05) than other inoculants. The control group also had a notably higher ammonia nitrogen content. In conclusion, while single-strain inoculants like Lactiplantibacillus plantarum are effective for rapid acidification, the use of combined bacterial strains can further enhance silage quality by improving lactic acid fermentation and nutrient preservation, particularly in treatments like Lactiplantibacillus plantarum and Pediococcus pentosaceus and Lactiplantibacillus buchneri and Enterococcus faecium.
This study aims to analyze the natural frequency characteristics of multi-cracked extensible beams. The model and governing equations of the multi-cracked beam were derived using Hamilton's principle while considering crack energy. The eigenmode functions were obtained through eigenvalue analysis by applying the patching conditions of the cracks, and the equations for the discretized cracked beam were formulated and solved. The displacement responses from nonlinear system analysis were used to calculate frequencies via Fast Fourier Transform (FFT), and the frequency characteristics were systematically analyzed with respect to the number of cracks, crack depth, and cross-sectional loss. Additionally, the natural frequencies and orthonormal bases of the linear system were derived by exploring the solutions of the characteristic equation reflecting the cracks. Numerical analyses showed that the natural frequency of a cracked extensible beam was higher than that of a cracked EB beam. However, as the number or depth of cracks increased, the natural frequency gradually decreased. Notably, in extensible beams with large deflections, the dynamic changes caused by cracks demonstrated results that could not be obtained through the EB beam model.
이 연구의 목적은 예비 지구과학 교사들이 선다형 문항 제작 실습 프로그램에 참여하는 과정에서 드러나는 문 항 제작 역량의 발달 양상을 이해하는 것이다. 이를 위해 예비 지구과학 교사 15명이 선다형 문항 제작 과정 중 공동 검토 과정에서 나타나는 논의에 초점을 맞춰 그 특징을 분석하였다. 구성주의 근거 이론을 토대로 3단계의 코딩을 수 행한 결과, 36개의 초기 코드, 12개의 초점 코드, 5개의 이론적 코드가 도출되었다. 코딩 범주에 근거하여 논의의 특징 을 규정하는 검토 문화와 문항에 대한 관점을 두 축으로 설정하였으며, 이로부터 수험생의 문제풀이, 조심스레 한 걸음 떼기, 짙어지는 담화를 주제로 하는 세 가지 이야기를 구성하였다. 또한 프로그램 동안 일관되게 드러나는 문항 제작 역량의 한계를 다다르지 못한 노정에 대한 네 번째 이야기로 서술하였다. 문항 제작 과정에서 드러나는 평가 전문성은 예비교사의 정체성 발달과 관련되어 있으며, 본 연구에서 적용한 개발한 프로그램의 효과와 의의 및 프로그램의 개발과 개선을 위한 시사점을 논의하였다.
The purpose of this study was to evaluate the quality properties of Meju prepared by inoculating two strains of Bacillus amyloliquefaciens HJ5-2, and Aspergillus oryzae PS03. The three soybean varieties that include Daewonkong, Daechan, and Saedanbaek were used in this experiment. The fermentation temperature during the Meju aging varied at 20℃, 30℃, and 40℃, respectively. The physicochemical analysis of the soybeans, showed that the cured protein and fat contents were 34.83~43.49% and 12.91~18.90%, respectively. The pH and total acidity were 6.47~6.93 and 0.11~1.22%, respectively. The change in appearance of the Meju was that the yellow-green mold was well formed on seven days at fermentation temperature of 20℃ and 30℃, but at 40℃, there was minimal mold formation and cracking of the surface. The amino nitrogen content was highest on the Daechan Meju at 621.83 mg% for seven days. The amylase increased as the fermentation period increased in all samples, and the protease increased rapidly until the first day of the fermentation, and then gradually increased thereafter. The total number of bacteria increased or decreased as the fermentation proceeded to 6.66~10.07 log CFU/g. The mold counts increased with increasing fermentation period in the range of 6.38~8.79 log CFU/g.
본 연구에서는 해양수산부 연안침식 실태조사에서 운영 중인 해운대 해수욕장 비디오 모니터링 시스템을 이용하여 연안정비 사업 실시 이후의 백사장 면적변화를 분석하였다. 해운대 해수욕장은 연안정비사업을 통한 대규모 양빈이후 계절변동 특성과 함께 해빈 안정화 과정을 거치면서 잘 유지되었으나, 최근 2년간 복수의 태풍 내습에 의하여 해운대 해수욕장의 계절변동특성 및 해빈안정화 양상은 균형을 상실하였으며, 급격한 침식이 발생하였다. 특히, 2018년 태풍 솔릭, 콩레이에 의해 침식된 백사장은 계절변동에 의한 겨울철 해빈면적을 회복하지 못하였으며, 2019년에 내습한 다수의 태풍들로 인하여 해빈면적이 전년 대비 9.5 %(12,607 m2) 감소하였다. 해운대 해빈 전면에서 관측된 파랑자료와 해빈면적자료를 분석한 결과, 계절에 따른 입사파향에 따라 백사장의 서측, 중앙부, 동측의 침퇴적 경 향이 뚜렷이 나타났다. 향후에는 계절변동특성의 둔화와 지속적인 침식경향이 나타나는 원인을 파악하기 위해 잠제 시설물의 마루높이, 기능유지 여부 및 잠제 외부로의 모래유출추적 등 보다 정밀한 모니터링이 필요하다.
In this study, indoor radon concentrations were measured in 56 multiple-use facilities located in Gwangju area from December 2017 to December 2018. The average indoor radon concentration in underground space was 51.70 Bq/m3, and that of the 1st floor was 38.73 Bq/m3, indicating that the indoor radon concentration of underground space was higher than that of the 1st floor. The indoor radon concentration was investigated according to the presence or absence of underground space. The concentration of radon on the 1st floor with underground space was 37.25 Bq/m3, and the concentration of radon on the ground floor without underground space was 47.94 Bq/m3. In the absence of underground space, indoor radon concentration was high. The indoor radon concentration of buildings over 30 years old was 87.26 Bq/m3, indicating a significantly higher indoor radon concentration compared to those of buildings less than 30 years old. The indoor radon concentration was investigated according to the operation of a ventilator. The indoor radon concentration of space without an operating ventilator was 52.17 Bq/m3, and that of space with a ventilator in operation for more than 8 hours per day was 36.31 Bq/m3. This result shows that the indoor radon concentration in the space with an operating ventilator is lower than the space where the ventilator is not in operation. The indoor radon concentration in the space with an operating ventilation system was lower than that on the same floor of the same building, and the indoor radon concentration of enclosed space was about 4.4 times higher than that of open space in the same building. In addition, the indoor radon concentration was measured according to the spatial features. The concentration of indoor radon of enclosed space was 64.76 Bq/m3, which is higher than those of an open space and an active space.
막여과 정수처리 공정에서는 효율적 처리와 관리를 위하여, 일정용량의 계열(Train)을 복수로, 고회수율 달성을 위한 다단(Stage)의 구성을 사용한다. 이에 따라, 각 계열 또는 단이 처리해야하는 대상수의 농도가 서로 상이하고, 원수 및 약품의 유입위치와 방향 등에 따라 막오염 특성이 서로 상이하다. 따라서, 본 연구에서는 다수의 계열과 2단으로 구성된 침지식 막여과 정수처리 공정에서 계열 및 단별 오염특성을 파악코자 하였다. 10년 이상 운영이 지속된 막여과 정수처리 공정을 대상으로 한 오염평가실험에서, 전단/앞 계열에서는 무기오염이, 후단/후 계열에서는 유기오염이 상대적으로 높게 나타나는 것을 확인하였으며, 이러한 자료를 바탕으로 막여과공정의 운영관리 방안을 제시할 수 있을 것으로 판단된다.
이 연구는 성인 남녀 462명을 대상으로 사전 설문검사를 통해 성별, 손잡이, 혈액형, 연령 등의 개인별 특성 집단과 다중지능 유형별 점수를 분류하였다. 그런 다음 뇌파측정시스템을 이용하여 전전두엽 부위인 Fp1 과 Fp2 부위에 측정 전극을 부착하고 무자극 상태와 순수한 Pink noise 청각자극 상태에서의 집중력의 변화와 다중지능과의 관계를 알아보고자 하였다. 공분산분석 결과, 무자극에 비해 Pink noise 자극시 대상자 전체의 평균 집중력이 유의하게 높게 나타났다. 개인별 특성에서는 남녀 성별을 제외한 왼손잡이, A형, 30대 집단에서 집중력이 유의하게 높게 나타났다. 그리고 무자극에 비해 Pink noise 상태의 집중력은 공간적 지능과의 관계가 더욱 강화되었고, 음악적 지능과는 음적 상관관계를 형성하였다. 이러한 결과는 집중력 향상을 위한 Pink noise 활용 시 개인별 특성을 반영해야할 필요성이 있음을 시사하였다.
Taguchi's robust design methodology has focus only a single characteristic or response, but the quality of most products is seldom defined by a characteristics, and is rather the composite of a family of characteristics which are often interrelated and nearly always measured in a variety of units. The multiple characteristics problem is how to compromise the conflicts among the selected levels of the design parameters for each individual characteristic. This paper presents a Taguchi-like approach based upon improved weighted main effects. One case study is solved by the proposed method.
This paper presents the optimization steps with weight and importance of estimated characteristic values in the multiresponse surface analysis(MRA). The research introduces the shape parameter of individual desirability function for relaxation and tighening of specification bounds. The study also proposes the combinded desirability function using arithmetic, geometric and harmonic means considering the measurement unit and numerical pattern.
Process capability indices are widely used in industries and quality assurance system. When designing the parameter on the multiple quality characteristics, there has been a study for optimization of problems, but there has been few former study on the possible conflicting phenomena in considertion of the correlations among the characteristics. To solve the issue on the optimal design for multiple quality characteristics, the study propose the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of terms. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index MCpm using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.
As technique that can contribute in quality improvement in design process to overcome shortcoming of traditional quality control, call design or development department quality control activity that is achieved to reduce gun damage shuddering at circle minimizing change or side effect of product performance as off-line quality control. This paper discuss optimal process design of investment projects expansion and replacement investment on each line or individual in the production. Generally optimal plant design has add to a few method by Subsidiary means with use a especial method. And then in this paper, a Robust design is presented, which may be effective to the processes appraisal or improvement. We propose that should make a optimal plant design model for reducing field failure rate to assign by real data on different factors in plant system. Using this model, robust design of taguchi method used in this comprehensive method for reducing field failure rate in plant system.
We purpose a decision model to select the optimal facilities for the Decision Making problems with multiple characteristics(nominal-is-best characteristics, larger-is -better characteristics, smaller- is -better characteristics). Using this model, concept of the loss function is used in this comprehensive method of for select the optimal preferred facilities. To solve the issue on the optimal preferred facilities for multiple characteristics, this study propose the loss function with cross-product terms among the characteristics and derived range of the coefficients of the terms.
The critical problem in dealing with multiple characteristics is how to compromise the conflict among the selected levels of the design parameters for each individual characteristic. In this study, First, Methodology using SN ratio optimized by univariate technique is proposed and a parameter design procedure to achieve the optimal compromise among several different response variables is developed. Second, to solve the issue on the optimal design for multiple quality characteristics, this study modelled the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of the terms. The model will be used to determine the global optimal design parameters where there exists the conflict among the characteristics, which shows difference in optimal design parameters for the individual characteristics. Third, this paper propose a decision model to incorporates the values assigned by a group of experts on different factors in weighting decision of characteristic. Using this model, SN ratio of taguchi method for each of subjective factors as well as values of weights are used in this comprehensive method for weighting decision of characteristic.
The hydrodynamic interaction characteristics between multiple floating bodies of semisubmersible type are examined for presenting the basic data for the design of huge offshore structures supported by a large number of the floating bodies in waves. The numerical approach is based on combination of a three-dimensional source distribution method and interaction theory which is exact within the context of linear potential theory. The method is applicable to an arbitrary number of three-dimensional bodies having any individual body geometries and geometrical arrangement with the restriction that the circumscribed, bottom-mounted, imaginary vertical cylinder for each body does not contain any part of the other body. The validity of this procedure was verified by comparing with numerical results obtained in the literature.