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Report for Development of Korean Portable Cardiopulmonary Bypass II. Experimental Study of Portable Cardiopulmonary Bypass for Emergency Cardiopulmonary Resuscitation after Cardiac Arrest in Normal Dogs (한국형 이동식 심폐소생기 개발 보고 II. 응급소생술을 위한 이동식 심폐소생기의 동물 실험 연구)

  • Kim, Hyoung-Mook;Lee, In-Sung;Baek, Man-Jong;Sun, Kyung;Kim, Kwang-Taik;Lee, Hye-Won;Lee, Kyu-Back;Chang, Jun-Kuen;Kim, Chong-Won;Kim, Hark-Jei
    • Journal of Chest Surgery
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    • v.31 no.12
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    • pp.1147-1158
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    • 1998
  • Background: Portable cardiopulmonary bypass(CPB) technique has been used increasingly as a potent and effective option for emergency cardiopulmonary resuscitation(CPR) because it can maintain more stable hemodynamics and provide better survival than conventional CPR techniques. This study was designed to develop a prototype of Korean portable CPB system and, by applying it to CPR, to discriminate whether it would be superior to standard open-chest CPR. Material and Method: By using adult mongrel dogs, open-chest CPR(OCPR group, n=4) and portable-CPB CPR(CPB group, n=4) were compared with respects to restoration of spontaneous circulation(ROSC), hemodynamics, effects on blood cells, blood gas patterns, biochemical markers, and survivals. Ventricular fibrillation-cardiac arrest(VF-CA) of arrest(VF-CA) of 4 minutes followed by basic life support(BLS) of 15 minutes was applied in either group, which was standardized by the protocol of American Heart Association. Then, advanced life support(ALS) was applied to either group under the support of internal cardiac massage or CPB. ALS was maintained until ROSC was achieved but not longer than 30 minutes regardless of the presence of ROSC. All of the measured values were expressed as means±SD percent change from baseline. Result: During the early ALS, higher mean arterial pressure was maintained in CPB group than in OCPR group(90±19 vs. 71±32 %; p<.05) and lower mean pulmonary arterial pressure was also maintained in CPB group than in OCPR group(105±24 vs. 146±6%; p<.05). ROSC was achieved in all dogs. Post-ROSC levels of hematocrit, RBC, and platelet were decreased and plasma free hemoglobin was increased significantly in CPB group compared to OCPR group(p<.05). Changes in blood gas patterns, lactate, and CK-MB levels were not different between groups. Early mortality was seen in 3 dogs in OCPR group(survival time 31±36 hours) and 2 in CPB group(228±153 hours, p=ns). The remainders in both groups showed prolonged survival. Conclusion: These findings indicate that portable CPB can be effective to maintain stable hemodynamics during cardiac arrest, to achieve ROSC and to prolong survival. Further study is needed to refine the portable CPB system and to meet clinical challenges.

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Estimation for N Fertilizer Application Rate and Rice (Oriza sativa L.) Biomass by Ground-based Remote Sensors (지상원격탐사 센서를 활용한 벼의 질소시비수준 및 생체량 추정)

  • Shim, Jae-Sig;Lee, Joeng-Hwan;Shin, Su-Jung;Hong, Soon-Dal
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.5
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    • pp.749-759
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    • 2012
  • A field experiment was conducted to selection of ground-based remote sensor and reflectance indices to estimate rice production, estimation of suitable season for ground-based remote sensor and N top dressing fertilizer application rate in 2010. Fertilizer application was determined by "Fertilizer management standard for crops" (National Academy of Agricultural Science, 2006). Four levels of N-fertilizer were applied as 0%, 70%, 100% and 130% by base N-fertilizer application and were fertilized as 70% of basal dressing and 30% as top dressing. Rice (Oryza sativa L.) of Chucheong and Joonam (Korean cultivar) were planted on May 22, 2010 in sandy loam soil and harvested on October 6, 2010. Reflectance indices were measured 7 times from July 5 to August 23 by Crop circle-amber and red version and GreenSeeker-green and red version. Remote sensing angle from the sensor head to the canopy of rice was adjusted to $45^{\circ}$, $70^{\circ}$ and $90^{\circ}$ degree because of difference in the density of plant and the sensing angle. The reflectance indices obtained ground-based remote sensor were correlated with the biomass of rice at the early growth stage and at the harvest with $70^{\circ}$ and $90^{\circ}$ degree of sensor angle. The reflectance indices at the 52th Day After Transplanting (DAT) and the 59th DAT, critical season, were positively correlated with dry weight and nitrogen uptake. Specially NDVI at the 59th was significantly correlated with the mentioned parameters. Based on the result of this study, rNDVI by GreenSeeker on $70^{\circ}$ degree of angle at the 59th DAT in Chucheong and rNDVI by Crop Circle on $70^{\circ}$ degree of angle and gNDVI by GreenSeeker on $70^{\circ}$ degree of angle at the 59th DAT in Joonam can be useful for estimation of dry weight and nitrogen uptake. Moreover, sufficiency index estimated by reflectance index at the 59th DAT can be useful for the estimation of N-fertilizer level application and can be used as a model for N-top dressing fertilizer management.

Four-Channel Differential CMOS Optical Transimpedance Amplifier Arrays for Panoramic Scan LADAR Systems (파노라믹 스캔 라이다 시스템용 4-채널 차동 CMOS 광트랜스 임피던스 증폭기 어레이)

  • Kim, Sang Gyun;Jung, Seung Hwan;Kim, Seung Hoon;Ying, Xiao;Choi, Hanbyul;Hong, Chaerin;Lee, Kyungmin;Eo, Yun Seong;Park, Sung Min
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.9
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    • pp.82-90
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    • 2014
  • In this paper, a couple of 4-channel differential transimpedance amplifier arrays are realized in a standard 0.18um CMOS technology for the applications of linear LADAR(laser detection and ranging) systems. Each array targets 1.25-Gb/s operations, where the current-mode chip consists of current-mirror input stage, a single-to-differential amplifier, and an output buffer. The input stage exploits the local feedback current-mirror configuration for low input resistance and low noise characteristics. Measurements demonstrate that each channel achieves $69-dB{\Omega}$ transimpedance gain, 2.2-GHz bandwidth, 21.5-pA/sqrt(Hz) average noise current spectral density (corresponding to the optical sensitivity of -20.5-dBm), and the 4-channel total power dissipation of 147.6-mW from a single 1.8-V supply. The measured eye-diagrams confirms wide and clear eye-openings for 1.25-Gb/s operations. Meanwhile, the voltage-mode chip consists of inverter input stage for low noise characteristics, a single-to-differential amplifier, and an output buffer. Test chips reveal that each channel achieves $73-dB{\Omega}$ transimpedance gain, 1.1-GHz bandwidth, 13.2-pA/sqrt(Hz) average noise current spectral density (corresponding to the optical sensitivity of -22.8-dBm), and the 4-channel total power dissipation of 138.4-mW from a single 1.8-V supply. The measured eye-diagrams confirms wide and clear eye-openings for 1.25-Gb/s operations.

Middle School Home Economics Teachers' Recognition of the Importance and the Level of Teaching Performance regarding the Contents of Morality Education in Home Economics Instruction (중학교 가정과교사의 가정교과에서의 도덕성 교육에 대한 중요도와 지도수행 정도)

  • Cho Mi Ok;Chae Jung Hyun
    • Journal of Korean Home Economics Education Association
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    • v.17 no.2
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    • pp.257-272
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    • 2005
  • The purpose of this study is to provide the basic data for morality of education in home economics education. Through research on the state of morality of education, the following criteria can be achieved ; recognition of the importance, and the level of teaching performance regarding the contents of morality education in home economics instruction. The basic data were obtained by looking at the differences between the recognized importance and the level of teaching performance. Data were collected from the survey mailed to the teachers responsible for home economics area in $\lceil$Technology${\cdot}$Home Economics$\rfloor$ in middle schools in Korea. The 335 questionnaires collected were used for final analysis. SPSS/WIN 10.0program was used for calculating and analysis the frequency, percentage, average. standard deviation. Firstly, most of the home economics teachers show that they continually try to implement morality education through each home economics lesson plan. They focus their attention on the main theme of the lesson of a particular nit, that deals with family life. For example, an excerpt from a particular unit may be the 'Understanding of myself and family members'. Most home economics teachers believe that a family setting and/or schools, whether private or public institutions, are appropriate places for productive education. As well, each of these educational settings, should take complete responsibility for teaching morality of education. As a way to activate the morality education, teachers believe that working with the students and understanding the needs of their students, along with the cooperation of parents, are key factors in the teaming process. Another way is the change of teacher's perceptions and educational conditions or environment. Secondly. home economics teachers in middle school. are showing a higher level of understanding on the importance regarding the contents of morality education, which can be noticed through the high level of their teaching performances. Regarding the importance of morality education, the first priority goes to showing respect for parents and the elderly, as well as sexual ethics and respect for life must always be taken into consideration. In regards to the level of teaching performance, the first priority goes to responsibility and co-operation. Secondly. showing respect for parents and the elderly and sexual ethics will be the third. Through data achieved through this study, the majority of home economics education teachers believe that morality education in home economics education is very important and a key factor in their teaching practices.

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The Work and Job Satisfaction of Paramedics in the Emergency Room of University Hospitals (대학병원 응급실 내 1급 응급구조사의 업무와 직무만족도)

  • Lee, Ok-Hee
    • The Korean Journal of Emergency Medical Services
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    • v.15 no.1
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    • pp.47-63
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    • 2011
  • Purpose : This research is to examine the work and job satisfaction of paramedics in the emergency room of university hospitals. This research is done to provide basic data needed for establishing work realms of paramedics in hospitals and to enhance their degree of satisfaction. Methods : Research questionnaire survey was conducted on 141 paramedics working in the emergency room of 32 university hospitals from August 24, 2010 to September 30, 2010 through direct visits and telephone interviews or email to explain the purpose of this research and assurance of confidentiality of responses on the questionnaires. As the tool for the degree of job satisfaction, 'The Index of Work Satisfaction' developed by Slavitt, et al(1978) and revised and supplemented by Soon-shim Kim and Hye-ran Kwon(2002) was used. The collected data were analyzed by evaluating frequency, percentage, mean, standard deviation, t-test and ANOVA, Cronbach's $\alpha$ by using SPSS WIN 18.0 program. Results : 1. Investigating the work and role of paramedics in the emergency room of university hospitals, electrocardiogram(EKG) was found to be highest with $\alpha$ was widely used with the rate of patient evaluation and test area. In the medical treatment for patients area, cardiopulmonary resuscitation(CPR) with 95%(134 persons) and ventilation assistance through ambu bagging(BVM) with 95%(134 persons) were found to be high. $\alpha$ were performed. In the role within the hospital and other areas, a member of CPR team in the hospital accounted for 78%(110 persons). 2. In the measurements of the job satisfaction of paramedics working at university hospitals, the total mean score was 2.91. The mean score in each question area indicated: section on job 3.48, autonomy 3.05, interaction 3.01, organizational demand 2.85, working conditions 2.67, salaries 2.40. This result obviously demonstrates the work of paramedics itself was most satisfied but the salaries were most dissatisfied. 3. In the measurements of the job satisfaction of paramedics working at university hospitals, job satisfaction based on the general characteristics showed significant difference in age (F=6.547, p=.002), gender (F=4.436, p=.000) marital status (F=-3.270, p= .001), religion (F=2.041, p= .043), motive for application (F=3.603, p= .015), and salary (F=6.658, p= .000). 대학병원 응급실 내 1급 응급구조사의 업무와 직무만족도 The Journal of the Korean Society of Emergency Medical Technology Vol. 15 (1) 63 4. In the measurements of the job satisfaction of paramedics working at university hospitals, job satisfaction based on the working environmental characteristics showed significant difference in total number of paramedics (F=3.779, p= .012), form of employment (F=5.601, p= .001), existence or non-existence of intention to change jobs (F=-4.037, p= .000). Conclusion : The work of paramedics in the emergency room of university hospitals consists of lots of treatment processes after specialized diagnosis and performance of professionally subdivided works. However, current legislation does not reflect such circumstances to which paramedics are exposed; thus, it should be considered for further revision and modification. The degree of job satisfaction of paramedics in the emergency room of university hospitals was high but low in salaries and working conditions were the weak points. The measures to enhance their degree of job satisfaction should be taken though improvement of labor conditions such as consideration of the rate of increase in salaries, compensation for overtime work, providing rest areas, improvement of current employment system, and conversion of temporary employees into regular employees.

ANALYSIS OF DIFFERENTIAL GENE EXPRESSION IN NORMAL, CYST AND AMELOBLASTOMA CELLS (정상, 낭종 및 법랑아세포종 세포에서의 유전자 발현 차이 분석)

  • Yang, Cheol-Hee;Baik, Byeong-Ju;Yang, Yeon-Mi;Kim, Jae-Gon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.32 no.1
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    • pp.75-88
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    • 2005
  • Ameloblastoma is the most commonly occurring odontogenic tumor in oral cavity. Although most are benign epithelial neoplasm, they are generally considered to be locally aggressive and destructive, exhibiting a high rate of recurrence. The biological behavior of this neoplasm is a slowly growing, locally invasive tumor without metastasis, therefore malignant neoplasm, changed its histological appearance to carcinoma or showed distant metastasis, is only defined clinically. In this study, we identified the differentially expressed genes(DEGs) in stages under benign or malignant ameloblastoma compared with normal patient using ordered differential display(ODD) reverse transcription(RT)-PCR and $GeneFishing^{TM}$ technology. ODD RT-PCR is rather effective when the investigation of samples containing very small amounts of total RNA must be accomplished. ODD RT-PCR used the means of amplification with anchored T-primer and adaptor specific primer. bearing definite two bases at their 3' ends and so this method could display differential 3'-expressed sequence taqs(ESTs) patterns without using full-length cDNAs. Compared with standard differential display, ODD RT-PCR is more simple and have enough sensitivity to search for molecular markers by comparing gene expression profiles, However, this method required much effort and skill to perform. $GeneFishing^{TM}$ modified from DD-PCR is an improved method for detecting differentially expressed genes in two or more related samples. This two step RT-PCR method uses a constant reverse primer(anchor ACP-T) to prime the RT reaction and arbitrary primer pairs(annealing control primers, ACPs) during PCR. Because of high annealing specificity of ACPs than ODD RT-PCR, the application of $GeneFishing^{TM}$ to DEG discovery generates reproducible, authentic, and long(100bp to 2kb) PCR products that are detectable on agarose gels. Consequently, various DEGs observed differential expression levels on agarose gels were isolated from normal, benign, and malignant tissues using these methods. The expression patterns of the some isolated DEGs through ODD RT-PCR and $GeneFishing^{TM}$ were confirmed by Northern blot analysis and RT-PCR. The results showed that these identified DEGs were implicated in ameloblastoma neoplasm processes. Therefore, the identified DEGs will be further studied in order to be applied in candidate selection for marker as an early diagnosis during ameloblastoma neoplasm processes.

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Employment Rate of Graduates of Agricultural Science Colleges in the Fields of Agro-industry (농학계열 대학 졸업생의 농산업 분야 취업률)

  • Kim, Jung Tae;Bae, Sung Eui
    • Journal of Agricultural Extension & Community Development
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    • v.21 no.4
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    • pp.1093-1124
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    • 2014
  • Studies on the role of agricultural science colleges are mostly divided into agricultural production, which is the primary function of agriculture, and other functions, which have recently begun to be emphasized as a result of social needs. With the green revolution and the aging of the farming population, there is a strong view that the role of agricultural science colleges should remain as it is. However, agriculture is expanding in terms of concept and content by converging with other industries not traditionally associated with agricultural production. Thus, the fields that now need to form part of agricultural science knowledge are becoming more detailed and expansive. The government's perception remains at the level of merely fostering farmers. This was evident in a survey on the employment rate, a factor used to evaluate colleges, in which the role of agricultural science colleges was limited to fostering farmers. Agro- industry fields, other than agriculturalists, include general industries in which the academic fields of agricultural science are combined with other academic fields. Thus, even when someone is employed in an industry that requires background knowledge of agricultural science, there is often a perception that he or she is employed in a field that is irrelevant to the major. This study examines the role of agricultural science colleges in agriculture and farm villages by focusing on the employment of graduates of these colleges within agro-industry. We categorize academic research on agricultural science into 16 fields, based on the medium level of the National Standard Science and Technology Classification Codes. Then, we categorize the employment fields into 168 fields, based on the small classification level of the inter-industry relations classification. Thus, we investigate 220 departments of 37 colleges, nationwide. Our findings show that the average employment rate of graduates of agricultural science colleges is 69.0%. Furthermore, 33.0% of all employees work in agro-industry fields that require background knowledge in agricultural science, which is one out of three job seekers. Then, 3.6% of employees work in business startups in agro-industry. The aforementioned government survey showed that only 0.1% of all college graduates in Korea were employed as agriculturalists in 2013. However, our results showed that 13.3% of graduates were working as agriculturalists, which is significantly different to the results of the government survey. These results confirm that agricultural science colleges contribute greatly to the employment of graduates, including farmers, agro-industry, and business startups in agro-industry fields.

Structure and Variation of Tidal Flat Temperature in Gomso Bay, West Coast of Korea (서해안 곰소만 갯벌 온도의 구조 및 변화)

  • Lee, Sang-Ho;Cho, Yang-Ki;You, Kwang-Woo;Kim, Young-Gon;Choi, Hyun-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.100-112
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    • 2005
  • Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

Three dimensional GPR survey for the exploration of old remains at Buyeo area (부여지역 유적지 발굴을 위한 3차원 GPR 탐사)

  • Kim Jung-Bo;Son Jeong-Sul;Yi Myeong-Jong;Lim Seong-Keun;Cho Seong-Jun;Jeong Ji-Min;Park Sam-Gyu
    • 한국지구물리탐사학회:학술대회논문집
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    • 2004.08a
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    • pp.49-69
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    • 2004
  • One of the important roles of geophysical exploration in archeological survey may be to provide the subsurface information for effective and systematic excavations of historical remains. Ground Penetrating Radar (GPA) can give us images of shallow subsurface structure with high resolution and is regarded as a useful and important technology in archeological exploration. Since the buried cultural relics are the three-dimensional (3-D) objects in nature, the 3-D or areal survey is more desirable in archeological exploration. 3-D GPR survey based on the very dense data in principle, however, might need much higher cost and longer time of exploration than the other geophysical methods, thus it could have not been applied to the wide area exploration as one of routine procedures. Therefore, it is important to develop an effective way of 3-D GPR survey. In this study, we applied 3-D GPR method to investigate the possible historical remains of Baekje Kingdom at Gatap-Ri, Buyeo city, prior to the excavation. The principal purpose of the investigation was to provide the subsurface images of high resolution for the excavation of the surveyed area. Besides this, another purpose was to investigate the applicability and effectiveness of the continuous data acquisition system which was newly devised for the archeological investigation. The system consists of two sets of GPR antennas and the precise measurement device tracking the path of GPR antenna movement automatically and continuously Besides this hardware system, we adopted a concept of data acquisition that the data were acquired arbitrary not along the pre-established profile lines, because establishing the many profile lines itself would make the field work much longer, which results in the higher cost of field work. Owing to the newly devised system, we could acquire 3-D GPR data of an wide area over about $17,000 m^2$ as a result of the just two-days field work. Although the 3-D GPR data were gathered randomly not along the pre-established profile lines, we could have the 3-D images with high resolution showing many distinctive anomalies which could be interpreted as old agricultural lands, waterways, and artificial structures or remains. This case history led us to the conclusion that 3-D GPR method can be used easily not only to examine a small anomalous area but also to investigate the wider region of archeological interests. We expect that the 3-D GPR method will be applied as a one of standard exploration procedures to the exploration of historical remains in Korea in the near future.

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Annual Increase in Carbon and Nitrogen Stocks of Trees and Soils in a 'Niitaka' Pear Orchard Following Standard Fertilization Recommendations (표준 시비에 따른 '신고'배 수체 및 재배지 토양의 탄소 및 질소 저장량 변화)

  • Ro, Hee-Myong;Choi, Jin-Ho;Lee, Seo-Yeon;Lee, Tae-Kyu;Kim, Jong-Sung;Park, Ji-Suk;Choi, Jang-Jeon;Lee, Min-Jin
    • Horticultural Science & Technology
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    • v.33 no.4
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    • pp.591-597
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    • 2015
  • We determined the total C and N stocks in trees and soils after 1 year of fertilization in an experimental orchard with 16-year-old 'Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees planted at $5.0m{\times}3.0m$ spacing on a Tatura trellis system. Pear trees were fertilized at the rate of 200 kg N, 130 kg P and $180kg\;K\;ha^{-1}$. At the sampling time (August 2013), trees were uprooted, separated into six fractions [trunk, main branches, lateral branches (including shoots), leaves, fruit, and roots] and analyzed for their total C and N concentrations and dry masses. Soil samples were collected from 0 to 0.6 m in 0.1 m intervals at 0.5 m from the trunk, air-dried, passed through a 2-mm sieve, and analyzed for total C and N concentrations. Undisturbed soil core samples were also taken to determine the bulk density. Dry mass per tree was 5.6 kg for trunk, 12.0 kg f or m ain branches, 15.7 kg for lateral branches, 5.7 kg for leaves, 9.8 kg for fruits, and 10.5 kg for roots. Total amounts of C and N per tree were respectively 2.6 and 0.02 kg for trunk, 5.5 and 0.04 kg for main branches, 7.2 and 0.07 kg for lateral branches, 2.6 and 0.11 kg for leaves, 4.0 and 0.03 kg for fruit, and 4.8 and 0.05 kg for roots. Carbon and N stocks stored in the soil per hectare were 155.7 and 14.0 Mg, respectively, while those contained in pear trees were 17.8 and $0.2Mg{\cdot}ha^{-1}$ based on a tree density of 667 trees/ha. Overall, C and N stocks per hectare stored in the pear orchard were 173.6 and 14.2 Mg, respectively. Compared with results obtained in 2012, the amounts of C stocks have increased by $17.7Mg{\cdot}ha^{-1}$, while those of N stocks remained virtually unchanged ($0.66Mg{\cdot}ha^{-1}$).