• 한국강구조학회 논문집
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• 제8권4호통권29호
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• pp.19-29
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• 1996

In this paper, it is presumed that the stress time history was generated by simulation method and investigated compatibility in regard to the reappearance of stress time history. In this procedure, the identified frequency distribution of stress range of the steel railroad bridge varies with the rational values of cut off point and bar width. Thus, we show variable aspect of the equivalent stress range results from change of cut off point and bar width. In addition, we analyze the variable of RMC and RMS model due to the cut off point and bar width of the measured stress history which influencs the prediction of fatigue life in the steel railroad bridge. The simulated stress time history is carried out by the superposition method incorporating the vertical load with rotation moment obtained from the Hermition interpolation function, and compared with developing stress results from measured maxi mum stress. Through this study, we can estimate the remaining fatigue life from a safety point of view and comparative accuracy.

• ALGAE
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• 제21권2호
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• pp.185-191
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• 2006

The morphology and life history of Stylonema reniforme Kajimura (Stylonematales, Rhodophyta) from Japan were investigated and its taxonomic placement was discussed. This species has 6-30 discoid chloroplasts devoid of a pyrenoid in each cell. This is a typical feature of the genus Goniotrichopsis. The species reproduced only by monospores, which were formed by the direct transformation of the vegetative cells similar to the type species Goniotrichopsis sublittoralis Smith. Goniotrichopsis reniformis (Kajimura) Kikuchi comb. nov. was proposed. The asexual life history of the present species was completed in 3-10 weeks at $15-20^{\circ}C$ in culture.

• 한국세라믹학회지
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• 제30권3호
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• pp.229-235
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• 1993

Thermal history and thermal stress of alumina specimen, which occured from thermal shock process, were calculated by finite difference method. Stress intensity factor and crack growth in cyclic thermal fatigue were calculated from single thermal shock temperature history and thermal stress. Cyclic thermal life were estimated by bending strength after cyclic thermal shock under critical thermal shock temperature. Calculated stress intensity factor was compared with real experimental thermal fatigue life of specimen. Fatigue life until critical stress intensity factor and real experimental result were comparable.

• 기록학연구
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• 제80호
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• pp.129-165
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• 2024

본 연구는 시민 구술채록의 중요성과 활성화를 강조하고자 한 글이다. 주지하는 바와 같이 우리나라는 1980년대부터 구술사연구가 서서히 시작되었다. 지금까지 연구자에 의한 시민인터뷰, 연구자에 의한 엘리트 인터뷰는 양적으로 꾸준히 증가했다. 그러나 시민에 의한 시민인터뷰는 미미한 수준이다. 2021년부터 문화체육관광부 주관으로 진행하고 있는 "디지털생활사 아카이빙"사업은 새롭고 의미 있는 시도이다. 이 사업은 시민들에게 아카이빙과 구술채록에 대한 교육을 거친 시민들이 직접 인터뷰를 수행하고 기록물을 생산하도록 하는 프로그램이다. 이 사업을 통해 구술기록 생산, 시민의 아카이빙 역량 확보, 지역 문화자원 구축 등의 성과를 내고 있다. 2021년에 이 사업에 참여했던 경험을 바탕으로 성과와 한계를 평가하며 시사점을 살펴보았다. 향후 시행착오를 줄이는 데 도움이 될 것으로 기대한다. 또한 시민 구술기록의 활발한 생산과 활용 방안을 제안하였다. 이를 위해 구술 기관 간의 구체적인 협력과 구술기록 플랫폼도 제안하였다.

• 한국수학사학회지
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• 제12권1호
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• pp.73-81
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• 1999

We survey the researches on self-reproducing structures on cellular automata. Self-reproduction is the foremost characteristic of life, and cellular automata are ideal model for studying artificial life. From the early studies by Von Neumann to late results on computational models using self-reproducing structures and emergence of self-replication are covered. Also possible applications of self-replicating structures are listed.

• Journal of Ginseng Research
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• 제16권2호
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• pp.146-150
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• 1992

Life history, ginseng damage, and chemical control of the snail Acusta despecta sieboldiana Pfeiffer were investigated in the field and laboratory conditions from 1987 to 1990. Eggs of the snail were whitish globular and 1.,93${\pm}$ 0.09 mm in diameter which were deposited as egg mass composed of 28.4${\pm}$ 15.4 eggs. Egg period was 11.8${\pm}$ 1.6 days under the laboratory condition. Most eggs were laid during mid July in the field. The snail had a life cycle of a year and hibernated from November to April. Significant ginseng damages by the snail (over 10% to the total number of plants) were observed only in the three to five year old ginseng fields with rice straw mulching. Based on the dates that the first ginseng damages were observed and on the questionary examination, ginseng damages seemed to occur from May to July. Metaldehyde (6%) bait showed reliable control effects on the snail.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.997-1002
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• 2007

A guideway vehicle is used in automobile, semiconductor and LCD manufacturing industries to transport products efficiently. Since the operating speed of the guideway vehicle should be increased for maximum productivity, the weight of the vehicle has to be reduced. This may cause parts in the system to fail before the life of the system. Therefore estimation of the fatigue life of the parts becomes an important problem. In this study, the fatigue life of the driving wheel in the guideway vehicle is estimated using a S-N curve. To obtain the fatigue life of a part, the S-N curve, load time history applied on a driving wheel and material property are required. The S-N curve of the driving wheel is obtained using the fatigue experiment on wheels. Load time history of the wheel is obtained from multibody dynamics analysis. To obtain the material properties of the driving wheel, which is composed of aluminum with urethane coating, a compression hardware testing has been done with the static analysis of the FE model. The fatigue life prediction using computational analysis model guarantees the safety of the vehicle at the design stage of the product.

• International Journal of Advanced Culture Technology
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• 제9권4호
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• pp.71-85
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• 2021

The history of the Bakken Museum, the Museum of Electricity in Life, is useful to understand the universality and particularity of a local science museum. Beginning with the small collections at the medical device company, the Bakken Museum has expanded its scope and facilities by reidentifying its mission from research institute to educational center. The educational turn of the Bakken Museum has been completed with two remarkable events: the launch of the Summer Institute in 1984 and the construction of the new education facility, New Wing, in 1999. During this change, the museum staff developed unique strategies for public engagement, using the history of science and technology as an educational tool. The shift of the Bakken Museum's mission provides an excellent example of how a local museum could meet the social needs for museums to be educational centers by utilizing its history and collections.

• Journal of Information Technology Applications and Management
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• 제29권5호
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• pp.27-37
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• 2022

This study intends to link agricultural machine history data with related organizations or collect them through IoT sensors, receive input from agricultural machine users and managers, and analyze them through AI algorithms. Through this, the goal is to track and manage the history data throughout all stages of production, purchase, operation, and disposal of agricultural machinery. First, LSTM (Long Short-Term Memory) is used to estimate oil consumption and recommend maintenance from historical data of agricultural machines such as tractors and combines, and C-LSTM (Convolution Long Short-Term Memory) is used to diagnose and determine failures. Memory) to build a deep learning algorithm. Second, in order to collect historical data of agricultural machinery, IoT sensors including GPS module, gyro sensor, acceleration sensor, and temperature and humidity sensor are attached to agricultural machinery to automatically collect data. Third, event-type data such as agricultural machine production, purchase, and disposal are automatically collected from related organizations to design an interface that can integrate the entire life cycle history data and collect data through this.

• 생태와환경
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• 제46권3호
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• pp.395-408
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• 2013

환경상태는 생물이 적합도 (번식성공 또는 생존율)를 극대화하기 위해서 초기생활사의 변화를 초래할 수 있다. 본 연구에서는 온도변화와 온도에 따른 수상레저활동 인구변화가 어류의 초기 생활사 특성, 즉 체세포 성장(성장속도), 번식세포 (생식소) 발달 그리고 누적스트레스의 회복과정과 어떠한 관계가 있는지를 동적상태의존모델을 이용하여 분석하였다. 우선 어류의 초기 생활사 특성이 취식행동에 영향을 받는다고 가정하였고, 이러한 관계를 고려하여 어류의 일반 생활사 모델을 개발하였다. 모델은 성장속도와 번식세포(생식소)의 발달이 온도가 상승함에 (단, 성장속도를 감소시키는 임계온도보다는 낮은) 따라 빨라졌으며, 또한 체내에 누적되는 스트레스도 함께 증가하였다. 흥미롭게도 온도가 높을 때에는 수상레저활동 인구의 증가는 성장속도와 생식소의 발달을 느리게 했지만, 스트레스의 누적은 가속화시켰다. 그러나 온도가 낮을 때에는 초기 생활사에 대한 수상레저활동 인구의 영향이 상대적으로 낮았다. 또한 최적취식행동은 높은 온도에서는 수상레저활동 인구의 변화에 관계없이 항상 높았지만, 낮은 온도에서는 수상레저활동 인구가 증가할수록 급격히 감소하였다. 초기성장기간 동안의 생존율은 온도가 낮아지고 수상레저활동 인구가 적을 때에는 취식행동이나 인간 활동에 따른 어류의 사망률 증감이 생존률 변이에 영향을 주었다. 반대로 온도가 높아지고 수상레저활동 인구가 많을 때의 생존율은 취식행동이나 사망률에 관계없이 항상 낮았다. 끝으로 본 연구를 통해 기후변화와 수상레저활동 인구변화와 관련된 어류의 초기 생활사를 수생태계 보전전략이나 건강성 평가분석에 포함시키는 것은 분석의 정확성과 정밀성을 향상시킬 수 있을 것이라 사료된다.