• Title/Summary/Keyword: History of Technology

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The Environmental Restoration and Revegetation Technology in Japan - The History of The Japanese Society of Revegetation Technology and the Problems of the Revegetation Technology in Japan - (일본(日本)의 환경(環境) 복원(復元) 녹화(綠化) - 일본녹화공학회의 발자취와 과제 -)

  • Masuda, Takuro
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.1 no.1
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    • pp.110-113
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    • 1998
  • It can be said that the revegetation technology in Japan was started in 1960's when Japan entered into the era of high-growth economy. In the beginning, the revegetation technology was mainly applied on the man made slopes, and with the time, the fields of the revegetation technology have been extended to the urban landscaping, ecosystem conservation, prevention of desertification and so on. With the progress of the revegetation technology and the expansion of its fields, new problems have occurred. In this paper, I introduced the history of The Japanese Society of Revegetation Technology and the present condition, and discussed about the problems of the revegetation technology in Japan.

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Developmental Characteristics and Life History of the Korean Native Firefly, Pyrocoelia rufa

  • Kim, Jong-Gill;Kim, Keun-Young;Park, Young-Cheol;Park, Ji-Young;Kim, Sam-Eun;Jin, Byung-Rae;Lee, Sang-Mong;Lee, Jong-Eun;Lee, Ki-Yeol
    • International Journal of Industrial Entomology and Biomaterials
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    • v.6 no.1
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    • pp.69-72
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    • 2003
  • Development and life history of the Korean native firefly, Pyrocoelia rufa, were investigated throughout the indoor rearing. Average size of egg with an oval shape was 1.7 m and the hatchability of egg of P. rufa was approximately 88.5%. The larvae were pupated at the ${5^th}$ instar and the body length of the matured larvae was 27.1 mm. The total periods of larval stage to the end of the 5$^{th}$ instar were approximately 104.7 days. Average pupal period was 10.3 days and average number of eggs oviposited by a female was 87.3 eggs. The body size of female in the pupa and adult was larger than that of male. The wings of female adult were deteriorated.

Developmental Characteristics and Life History of the Korean Native Fire-fly, Luciola lateralis

  • Kim, Jong-Gill;Kim, Sam-Eun;Park, Ji-Young;Yoon, Hyung-Joo;Park, Young-Cheol;Ohba Nobuyoshi;Jin, Byung-Rae;Noh, Si-Kap
    • International Journal of Industrial Entomology and Biomaterials
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    • v.3 no.2
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    • pp.141-147
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    • 2001
  • To study the ecological characteristics of the Korean native firefly, Luciola lateralis, development and life history of L. lateralis were investigated throughout the indoor rearing. Average size of egg with an oval shape was 0.51${\times}$0.56 mm and an egg period of L. tateralis was approximately 25.8 days. The larvae were pupated at the 5$^{th}$ instar and the body length of the matured larvae was 15.8mm. The total periods of larval stage to the end of the $5^{th}$ instar were approximately 271.7 days. Pupae formed soil cocoon and average pupal period was approximately 28.7 days. Average number of eggs oviposited by a female was approximately 97. The body size of female in the pupa and adult were larger that of male.

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Impact Force Reconstruction of Composite materials based on Improved Regularization Technology

  • Sun, Yajie;Yin, Tao;Yang, Jian;Cai, Zhiyu;Wu, Shaoen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.8
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    • pp.2718-2731
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    • 2021
  • In the structural health monitoring of composite materials, in order to solve the ill-posed problem of impact force reconstruction, regularization techniques are often used to deal with it. Due to the poor convergence of the traditional Tikhonov regularization method, in order to accurately reconstruct the time history of the impact force, this paper improves Tikhonov regularization method and constructs homotopy function with strong convergence. Since the optimal regularization parameters need to be found in the homotopy function, the Newton downhill method is used to find the optimal parameters and the homotopy function can be calculated, which can accurately reconstruct the time history of the impact force. In order to verify the universality of the method in this paper, impact hammers of different materials were used in the experiment in this paper to study and compare the reconstruction effect of impact time history of different impact hammers.

Improvement of the T-history Method to Measure Heat of Fusion for Phase Change Materials

  • Hong, Hi-Ki;Park, Chang-Hyun;Choi, Ju-Hwan;Peek, Jong-Hyeon
    • International Journal of Air-Conditioning and Refrigeration
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    • v.11 no.1
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    • pp.32-39
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    • 2003
  • Though conventional calorimetry methods such as differential scanning calorimetry and differential thermal analysis are used generally in measuring heat of fusion, T-history method has advantages of a simple experimental apparatus and no requirements of sampling process, which is particularly useful for measuring thermophyical properties of in-homogeneous phase change materials in sealed tubes. However, the degree of supercooling used in selecting a range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion. In the present study, it was shown that a 40% discrepancy exists between the original T-history and the present methods when analyzing the same experimental data. As a result, a reasonable modification to the original T-history method is proposed.

An Analysis of Location Management Cost by Predictive Location Update Policy in Mobile Cellular Networks (이동통신망에서 예측 위치 등록 정책을 통한 위치관리 비용 감소 효과 분석)

  • Ko, Han-Seong;Hong, Jung-Sik;Chang, In-Kap;Lie, Chang-Hoon
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.2
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    • pp.160-171
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    • 2008
  • MU's mobility patterns can be found from a movement history data. The prediction accuracy and model complexity depend on the degree of application of history data. The more data we use, the more accurate the prediction is. As a result, the location management cost is reduced, but complexity of the model increases. In this paper, we classify MU's mobility patterns into four types. For each type, we find the respective optimal number of application of history data, and predictive location area by using the simulation. The optimal numbers of four types are shown to be different. When we use more than three application of history data, the simulation time and data storage are shown to increase very steeply.

Fuel Consumption Prediction and Life Cycle History Management System Using Historical Data of Agricultural Machinery

  • Jung Seung Lee;Soo Kyung Kim
    • Journal of Information Technology Applications and Management
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    • v.29 no.5
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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.

A Study of Medical Record about Delegation Dispatched to Japan in Chosun Dynasty (조선통신사 사행원과 기록 연구 -18세기 사행록과 의학문답 기록을 중심으로-)

  • Ham, Jeong Sik;Cha, Wung Seok;Yoo, Won Joon;Kim, Nam Il
    • The Journal of Korean Medical History
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    • v.20 no.1
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    • pp.41-61
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    • 2007
  • In 1607 a delegation was dispatched from Chosun to Japan (under the condition that prisoners of war were returned) to restore the destroyed relationship between the nations due to a war and to restore economic profits. This delegation later on became a delegation representing faith in each other. It contributed greatly to the Korea-Japan cultural exchanges in the 17th and 18th centuries. It was also a cornerstone for the exchange of Korea's distinguished studies as well as medical technology and Japan's results of international trade such as sweet potatoes, pepper, and tobacco. This thesis is one that discusses the study of documents produced during this process.

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Effect of Boundary Condition History on the Symmetry Breaking Bifurcation of Wall-Driven Cavity Flows

  • Cho, Ji-Ryong
    • Journal of Mechanical Science and Technology
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    • v.19 no.11
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    • pp.2077-2081
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    • 2005
  • A symmetry breaking nonlinear fluid flow in a two-dimensional wall-driven square cavity taking symmetric boundary condition after some transients has been investigated numerically. It has been shown that the symmetry breaking critical Reynolds number is dependent on the time history of the boundary condition. The cavity has at least three stable steady state solutions for Re=300-375, and two stable solutions if Re>400. Also, it has also been showed that a particular solution among several possible solutions can be obtained by a controlled boundary condition.