• Title/Summary/Keyword: Time Study

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Novel LTE based Channel Estimation Scheme for V2V Environment (LTE 기반 V2V 환경에서 새로운 채널 추정 기법)

  • Chu, Myeonghun;Moon, Sangmi;Kwon, Soonho;Lee, Jihye;Bae, Sara;Kim, Hanjong;Kim, Cheolsung;Kim, Daejin;Hwang, Intae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.3
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    • pp.3-9
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    • 2017
  • Recently, in 3rd Generation Partnership Project(3GPP), there is a study of the Long Term Evolution(LTE) based vehicle communication which has been actively conducted to provide a transport efficiency, telematics and infortainment. Because the vehicle communication is closely related to the safety, it requires a reliable communication. Because vehicle speed is very fast, unlike the movement of the user, radio channel is rapidly changed and generate a number of problems such as transmission quality degradation. Therefore, we have to continuously updates the channel estimates. There are five types of conventional channel estimation scheme. Least Square(LS) is obtained by pilot symbol which is known to transmitter and receiver. Decision Directed Channel Estimation(DDCE) scheme uses the data signal for channel estimation. Constructed Data Pilot(CDP) scheme uses the correlation characteristic between adjacent two data symbols. Spectral Temporal Averaging(STA) scheme uses the frequency-time domain average of the channel. Smoothing scheme reduces the peak error value of data decision. In this paper, we propose the novel channel estimation scheme in LTE based Vehicle-to-Vehicle(V2V) environment. In our Hybrid Reliable Channel Estimation(HRCE) scheme, DDCE and Smoothing schemes are combined and finally the Linear Minimum Mean Square Error(LMMSE) scheme is applied to minimize the channel estimation error. Therefore it is possible to detect the reliable data. In simulation results, overall performance can be improved in terms of Normalized Mean Square Error(NMSE) and Bit Error Rate(BER).

A Study on the Sailing Speed of Ancient Ships - especially on the average speed and the effect of the wind, the tide, and the man-power at the oar - (고대 선박의 항해속도 연구 - $\ll$고려도경$\gg$을 중심으로-)

  • Yoon, Il-Young
    • Journal of National Security and Military Science
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    • s.7
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    • pp.155-231
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    • 2009
  • Xu-Jing(徐競) an official of the Song(宋), a medieval Kingdom of China, wrote a book titled $\ll$Koryo Tu Jing(高麗圖經)$\gg$ which explains his travel to the Koryo as a member of diplomatic mission in 1123. $\ll$Koryo Tu Jing$\gg$ is the record of his personal experience in Koryo with many explanatory illustrations and especially contains 5 months' voyage record of his diplomatic fleet. His fleet set sail at a port located in the Ding Hai Xian(定海縣), Ming Zhou(明州) via a few islands of Koryo [Hyup Kye San(俠界山) , the Kun San Do(群山島) , the Ja Yon Do(紫燕島) , the Keup Su Mun(急水門) in Kang Hwa Gun(江華郡) and the Hap Gul(蛤窟) ] and finally arrived the Port Ye Song Hang(禮成港) . According to the Xu-Jing's record his fleet sailed the sea with the help of the favorable seaward winds and tides as the usual way of ancient sailing. The Xu- Jing's Fleet sailed the sea between the Mei Cen(梅岑), Ming Zhou(明州) of China and the Hyup Kye San(俠界山) of Koryo from about 5:00 a.m., May 24th(of the lunar calendar) to about 5:00 p.m., June 2nd. At this section, the average speed of the seaward winds was 19.45km/h and the average speed of the fleet which sailed only by the power of the winds was 6.29km/h. This means that 32.3% of the favorable seaward winds' speed was equal to the speed of the ancient fleet which sailed only by the power of the favorable seaward winds. The fleet sailed the sea between the Ja Yon Do(紫燕島) and the Keup Su Mun(急水門) from about 9:00 a.m., June 10th to about 1:00 p.m., the same day. At this section the fleet sailed by the power of tides in addition to the favorable seaward winds without oaring. The average speed of the winds was not different from that of former section and the average speed of the tides was 1.937km/h. And at this section the average speed of the fleet increased by 0.41km/h than that of the former section. This means that 21.1% of the speed of the tides was equal to the increased speed of the ancient fleet by virtue of the tides. The fleet sailed the sea between Keup Su Mun(急水門) and the Hap Gul(蛤窟) from about 1:00 p.m., June 10th to about 3:00 p.m., the same day. At this section, there were no seaward winds and the fleet sailed only by the powers of tides and oaring. And at this section, the tide increased the average speed of the fleet by 0.3114km/h and the fleet could sail at the speed of 4.3km/h. So we can conclude that the average speed of ancient fleet without any influences of the seaward winds and tides was 3.98 km/h. We can make use of the various sailing speeds of ancient fleets when judging their maritime activities. If we make use of the various sailing speeds of the ancient fleets as calculated in this article, we will be able to get various important informations about the certain ancient fleet's maritime maneuver. For example, we can infer the sailing routs of a certain fleet and the time when the fleet passed a certain spot by making use of the various sailing speeds of the ancient fleet. In this article I did not take account of the shapes of ships that consist of the ancient fleets and the sizes of the various ships and fleets. It was because that such factors would not change the foresaid conclusions seriously.

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Effect of Thyroid Function on Histological changes of Hypophysis and Serum FSH and LH Concentrations in Female Rats (흰쥐의 갑상선기능(甲狀腺機能)이 하수체(下垂體)의 조직변화(組織變化)와 혈청중(血淸中) FSH 및 LH의 농도(濃度)에 미치는 영향(影響))

  • Seo, Kil Woong;Lee, Kyu Seung;Kim, Young Mook
    • Korean Journal of Agricultural Science
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    • v.11 no.2
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    • pp.252-263
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    • 1984
  • This study was conducted to find out the effect of thyroid function on Hypophysis, and serum FSH and LH concentrations in female rats. One hundred and forty-four female rats (wistar-imamichi albino rats) of 25 days old were divided into 4 groups; thyroidectomy (Thx.) propylthiouracil (PTU), thyroxine (Thyro.) and control (Cont.) groups. Thirty-six heads of rats were arranged to each group. The thyroid glands of the thyroidectomized groups were removed by surgery. The PTU treated groups were drunk the propylthiouracil solution of 0.05% and the thyroxine treated groups were administered subcutaneously with $30{\mu}g$ per 100 g body weight on 3 days intervals. Every 6 heads of rats in each group were sacrificed at 1, 2, 3, 4, 5, and 6 weeks after treatment with time elapse for investigating the weights and histological changes of hypophysis. The results obtained were as follows : 1. The weights of hypophysis at all treated groups were higher than control group, but significantly increased from 3 to 5 weeks. The significance was not recognized between Thyro. and control groups, and Thx. and PTU groups. 2. In the histological changes of hypophysis, eosinophils atrophied from 4 weeks after treatment in Thx. and PTU groups, and basophils showed hypertrophy and hyperplasia from 2 weeks after treatment and thereafter this tendency was more serious showing vacuolization from 4 weeks after treatment. In Thyro. treated group, eosinophils showed slight hypertrophy and basophils atrophied from 5 weeks after treatment but the group showed the similar histological changes in comparison with the control group. 3. The changes of the concentrations of serum FSH at all observation times were significantly recognized among all observation groups. The concentrations in True and PTU groups were significantly lower than those in control group, but those in Thyro. group were significantly higher than those in control group. 4. The changes of the concentrations of serum LH in all treated groups were significantly lower than those in control group. The significance was not recognized between True and PTU group, and Thyro. and control groups.

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Plant Characteristics and Dry Matter Production of Several Rice Varieties (수도품종(水稻品種)의 초형(草型)과 건물생산특성(乾物生産特性)의 변천(變遷))

  • Kim, Hong Kyu;Ahn, Su Bong
    • Korean Journal of Agricultural Science
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    • v.14 no.2
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    • pp.248-262
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    • 1987
  • This experiment was conducted to study plant characteristics and dry matter production of several rice varieties. The results are summarized as follows. 1. Culm length was gradually shortened as varieties were improved and showed significant decrease in Japonica X Indica hybrids. 2. Panicle length seems to be shortened as varieties changed from group I to group III. However, varieties in group IV had longer panicle length in spite of shortening tendency in other groups. 3. Leaf blade length was decreased as varieties improved, but leaf blade width was increased. 4. Panicle exertion showed significant decrease as varieties improved. 5. Number of panicles per square meter among Japonica varieties was gradually increased and similar to the number of spikelets per panicle. Number of spikelets on Indica X Japonica hybrids were higher than Japonica varieties, whereas 1,000 kernel weight was slightly decreased. 6. Dry weight of leaf sheath and culm, and leaf blade was highest at the time of heading and the weight of panicle showed significant increase between 10 and 20 days after heading. 7. The maximum crop growth ratios of leaf blade, stem and panicles were attadined at the stage of heading, booting and milking, respectively. 8. The distribution ratio of dry matter was higher in leaf blade than in stem at the tillering stage. At the heading stage, the distribution ratio of dry matter was higher in order of culm, leaf blade and panicle. At the maturing stage, the ratio was higher in order of panicle, stem and laf blade. 9. Correlation coefficients among grain yield, harvest index, and biological yield were all significant and they were positive.

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Performance Analysis of Implementation on IoT based Smart Wearable Mine Detection Device

  • Kim, Chi-Wook
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.12
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    • pp.51-57
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    • 2019
  • In this paper, we analyzed the performance of IoT based smart wearable mine detection device. There are various mine detection methods currently used by the military. Still, in the general field, mine detection is performed by visual detection, probe detection, detector detection, and other detection methods. The detection method by the detector is using a GPR sensor on the detector, which is possible to detect metals, but it is difficult to identify non-metals. It is hard to distinguish whether the area where the detection was performed or not. Also, there is a problem that a lot of human resources and time are wasted, and if the user does not move the sensor at a constant speed or moves too fast, it is difficult to detect landmines accurately. Therefore, we studied the smart wearable mine detection device composed of human body antenna, main microprocessor, smart glasses, body-mounted LCD monitor, wireless data transmission, belt type power supply, black box camera, which is to improve the problem of the error of mine detection using unidirectional ultrasonic sensing signal. Based on the results of this study, we will conduct an experiment to confirm the possibility of detecting underground mines based on the Internet of Things (IoT). This paper consists of an introduction, experimental environment composition, simulation analysis, and conclusion. Introduction introduces the research contents such as mines, mine detectors, and research progress. It consists of large anti-personnel mine, M16A1 fragmented anti-mine, M15 and M19 antitank mines, plastic bottles similar to mines and aluminum cans. Simulation analysis is conducted by using MATLAB to analyze the mine detection device implementation performance, generating and transmitting IoT signals, and analyzing each received signal to verify the detection performance of landmines. Then we will measure the performance through the simulation of IoT-based mine detection algorithm so that we will prove the possibility of IoT-based detection landmine.

The reserch of Kim hong-kyung's view of extra meridians -With the connection yin yang wei qiao mai With four trigram constitution theory- (김홍경의 기경팔맥관(奇經八脈觀)에 관한 연구(硏究) - 음양유교맥(陰陽維蹻脈)과 사상체질(四象體質)의 상관성을 중심으로 -)

  • Jung, Hae-Myeong;Yun, Chang-Yeol
    • Journal of Haehwa Medicine
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    • v.22 no.2
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    • pp.13-21
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    • 2014
  • Subject : Kim hong-kyung(金洪卿)'s view of eight extra meridians Object : Kim hong-kyung has not only deeply studied Saam acupuncture but also the function and characteristics of extra meridian at the same time. Especially, he has tried the study to connect yin yang wei qiao mai(陰陽維蹻脈) with Lee je-ma(李濟馬)'s four trigram constitution theory, therefore the author felt the need to make public the theory and started reserch on the theory. Method : I researched the physiological properties of extra meridians through the past eastern medical literature, I reported on the types of people to show well the properties of extra meridians gathering Kum-oh's verbal explanation when I had classes from him. Result : Kum-oh Kim hong-kyung defined meridians as passways of consciousness and feeling, he interpreted 12 meridians and extra meridians with the view of mind, which has very important meanings in the history of acupuncture in the point of first trial to interpret meridians from this view. He explained Ren mai(任脈) and Du mai(督脈) are meridians which show clearly properties of yin-yang to appear trusts of affirmation and distrusts of denial in the mind, as Ren(任) means entrusting and Du(督) means supervising in English. He explained Chong mai(衝脈) is the meridian representing impulsive man that has a meaning of impulse as being suggested the name of Chong mai, because Chong mai is borrowed from Foot shao yin kidney meridian(足少陰腎經). Dai mai(帶脈) is the meridian representing the characteristics of woman that has a meaning of binding as being suggested from the name of Dai mai which acts when people have something on their flank or they are pregnant, because Dai mai borrowed from Foot shao yang gall bladder meridian. He thought that four trigram divided from yin and yang is innate trigram, so Yang wei mai(陽維脈), Yin wei mai(陰維脈), Yang qiao mai(陽蹻脈), Yin qiao mai(陰蹻脈) among extra meridians have connections with Tai-yang ren(太陽人), Tai-yin ren(太陰人), Shao-yin ren(少陰人), Shao-yang ren(少陽人) of Four trigram constitution theory respectively which was created by Lee je-ma. He explained yang means opponents and wei(維) means binding. Yang wei mai is the meridian to be active when opponents bind or intervene in you, also the meridian is well active to the people who easily criticize others who are rude, to the people who well refuse restraints from organization. Because he explained yin means me and wei(維) means binding. Yin wei mai is the meridian to be active when I bind and intervene in opponents. He also state that the meridian is easily active to the people who have a tendency to gather people and make party apparatus by nature. He explained Yang qiao mai is the meridian to be active in the situation that people are waiting for others to bridge gap because yang means opponents and qiao(蹻) which has a meaning of standing on one's tiptoes means bridging gap between people. He also state the meridian is easily active to Shao yin ren who has a tendency to be passive, to easily settle down and not to move by nature. He explained Yin qiao mai is the meridian to be active in the situation that I bridge gap between me and others to make friends, because yin means me and qiao(蹻) which has a meaning of standing on one's tiptoes means bridging gap between me and others. He also state the meridian is easily active to Shao yang ren who is active in every business and who has remarkable ability to make friends. Conclusion : Kim hong-kyung stated the physiological properties of extra meridians as below. Ren mai is the meridian representing positive confidence which is easily active when people have a mind to trust others, Du mai is the meridian representing negative distrust which is easily active when people have doubts. Chong mai is the meridian representing the characteristics of man that has impulsive characteristics. Dai mai is the meridian representing the characteristics of woman to be easily active when she is pregnant. Yang wei mai has close connections with Tai-yang ren who has a tendency to refuse restraints from others and to criticize on opponent's remarks and behaviors that are wrong. Yin wei mai has close connections with Tai-yin ren, as the meridian is active in the situation that people enjoy restraining and intervening in others. Yang qiao mai has close connections with Shao yin ren, as the meridian is active to the people who are negative and passive by nature. Yin qiao mai has close connections with Shao yang yin who has a strong tendency to make friends easily by nature.

Restoration for Evergreen Broad-leaved Forests by Successional Trends of Pasture-grassland in the Seonheulgot, Jeju-do (제주도 선흘곶 초지지역의 천이경향을 고려한 상록활엽수림 복원 연구)

  • Han Bong-Ho;Kim Jeong-Ho;Bae Jeong-Hee
    • Korean Journal of Environment and Ecology
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    • v.18 no.4
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    • pp.369-381
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    • 2004
  • This study was achieved to present the way to restore the Seonheulgot pasture-grassland damaged by landuse and interference for a long time to evergreen broad-leaved forests as the native vegetation structure. As a result of analyzing ecological succession tendency of structure in survey area, we established the optimal restoration model. The total of survey sites were 26, and the classified plant community types were four types by M.I.P of dominant woody species. Finally we classified the four types based on diameter of dominant woody species in canopy layer. The six community types are as follows: Community I was runner-shrub forest, community II was evergreen broad-leaved shrub forest, and community III was evergreen broad-leaved forest of small diameter. Community IV and V were evergreen broad-leaved forest of middle diameter. Community Ⅵ was evergreen broad-leaved forest of large diameter. The number of constituent species was 24 in community I, 28 in community II as the shrub forest, 16 as the evergreen broad-leaved forest of small diameter, 29 in community III, 30 in community IV as the evergreen broad-leaved forest of middle diameter and 27 in community Ⅵ as the evergreen broad-leaved forest of large diameter. The range of Shannon's index of all communitys was from 0.8763 to 1.2630 and the Similarity index between the community composed of middle diameter woody species and large diameter woody species. The ecological succession of community I, II, and III were changed from pasture-grassland to broad-leaved forest and the structure of community IV, V, and Ⅵ was similar to evergreen broad-leaved forest in warm temperate region. We suggest the restoration planting model evergreen broad-leaved forest of in Seonheulgot pasture-grassland, as follows: The target restoration vegetation were Castanopsis cuspidata var. sievoldii community and Queycus glauca community. Castanopsis cuspidata var. sievoldii and Quercus glauca should be dominant woody species in canopy layer, the number of trees was 10 per 100$m^2$, and Castanopsis cuspidata var, sievoldii, Quercus glauca, Camellia japonica, and Eurya japonica should be dominant woody species in the understory layer, the number of trees was 14 per 100$m^2$.

Analysis of Ecotype, Growth and Development, Yield and Feed Value of Kenaf (Hibiscus cannabinus L.) Genetic Resources (케나프 수집 유전자원의 생태형·생육특성 및 수량과 사료가치 분석)

  • Kang, Chan-Ho;Yoo, Young-Jin;Choi, Kyu-Hwan;Kim, Hyo-Jin;Shin, Yong-Kyu;Lee, Gong-Jun;Ko, Do-Young;Song, Young-Ju;Kim, Chung-Kon
    • Korean Journal of Plant Resources
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    • v.27 no.5
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    • pp.556-566
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    • 2014
  • In this study, we collected 29 Kenaf (Hibiscus cannabinus L.) genetic resources from 10 countries to confirm the possibility of the introduction into Korea. The Kenaf (Hibiscus cannabinus L.) has the broad industrial use like feed and the 5 times more strong $CO_2$ absorption capacity compared to general plant. So recently it is considered as a good industrial source. We analyzed ecotype, growth and development, yield and feed value of collected resources. They were divided into 3 groups depending on flowering time, early maturing type blooming in early July, mid-late maturing type blooming from end of August to early September and late maturing type blooming in end of October. Early maturing type could get fruitful seed but dropped yield (average 7,895 kg/10a) and late maturing type could get high yield (average 12,572 kg/10a) but deletion. The other side mid-late maturing type could get yield over a certain level (average 11,207 kg/10a) and fruitful seed was ensured. The yields analyzed by resources indicated that K12 (Hongma 300) collected in China, K25 from India, K22 from Russia and K21 (Khonkaen 60) variety from China were more than 13,500 kg per 10a. Feed value of early maturing type had inclined to more better than other types, but like dry digestible matter (DDM) and dry matter intake (DMI) of some late maturing types like K12, K21, K22 which had a high yielding ability were more better than that of early maturing types'. So relative feed value (RFV) which considered comprehensive item for feed value were indicated K21 was 102.5, K12 was 116.2 and K22 was 120.2. 'Jangdae' the variety developed in Korea which could complement of other types' had a good quality for yield 10,975 kg/10a and 12.5% crude protein content and 101.9 of the relative feed value. So we need to be taken power to collection of mid-late maturing types resources.

Effects of Cultivated Wild Panax ginseng Extract on the Proliferation, Differentiation and Mineralization of Osteoblastic MC3T3-E1 Cells (산양삼(cultivated wild Panax ginseng) 추출물이 조골세포 활성에 미치는 영향)

  • Seo, Hyun-Ju;Eo, Hyun Ji;Kim, Hyun Jun;Jeon, Kwon Seok;Park, Gwang Hun;Hong, Se Chul;Jeong, Jin Boo
    • Korean Journal of Plant Resources
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    • v.33 no.4
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    • pp.227-236
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    • 2020
  • Panax ginseng C.A. Meyer (P. ginseng) is known to exert a wide range of pharmacological effects both in vitro and in vivo. Although studies on ginsenoside, antioxidant activity, and anticancer effect of the cultivated wild Panax ginseng (CWP) have been conducted, there is little research on the effect of CWP extract on bone metabolism. In this study, we investigated the potential anti-osteoporotic properties of CWP on the growth and differentiation of MC3T3-E1 cells. CWP significantly increased the viability and proliferation of MC3T3-E1 cells. CWP activated intracellular alkaline phosphatase (ALP) activity in MC3T3-E1 cells. In addition, CWP increased the mineralized nodules in MC3T3-E1 cells. Furthermore, CWP increased the expression of genes such as Runx2, ALP, OPN and OCN associated with osteoblast growth and differentiation in a dose-dependent manner.

A Dynamic Behavior Evaluation of the Curved Rail according to Lateral Spring Stiffness of Track System (궤도시스템의 횡탄성에 따른 곡선부 레일의 동적거동평가)

  • Kim, Bag-Jin;Choi, Jung-Youl;Chun, Dae-Sung;Eom, Mac;Kang, Yun-Suk;Park, Yong-Gul
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.517-528
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    • 2007
  • Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

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