• Title/Summary/Keyword: optimal

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A Study on the Effect of O$_2$ annealing on Structural, Optical, and Electrical Characteristics of Undoped ZnO Thin Films Deposited by Magnetron Sputtering (산소 어닐링이 마그네 트론 스퍼터링으로 증착된 undoped ZnO박막의 구조적, 광학적, 전기적 특성에 미치는 영향에 대한 연구)

  • Yun, Eui-Jung;Park, Hyeong-Sik
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.7
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    • pp.7-14
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    • 2009
  • In this paper, the effects of annealing conditions on the structural ((002) intensity, FWHM, d-spacing, grain size, (002) peak position), optical (UV peak, UV peak position) and electrical properties (carrier concentrations, resistivity, mobility) of ZnO films were investigated. ZnO films were deposited onto SiO$_2$/si substrates by RF magnetron sputtering from a ZnO target. The substrate was not heated during deposition. ZnO films were annealed in temperature ranges of $500\sim650^{\circ}C$ in the O$_2$ flow for 5$\sim$20 min. The film average thicknesses were in the range of 291 nm. The surface morphologies and structures of the samples were characterize by SEM and XRD, respectively. The optical properties were evaluated by photoluminescence (PL) measurement at room temperature (RT) using a He-Cd 325 nm laser. As the annealing temperature and time vary, the following relations were also observed: (1) proportional relationships among UV intensity (002) intensity, and grain size exist, (2) UV intensity is inversely proportional to FWHM, (3) there is no special relationship between UV intensity and electron carrier concentrations, (4) d-spacing is inversely proportional to (002) peak position, (5) UV peak position in the range of 3.20$\sim$3.24 eV means that ZnO films have a n-type conductivity which was consistent with that obtained from the electrical property, (6) the optimal conditions for the best optical and structural characteristics were found to be oxygen fraction, (O$_2$/(O$_2$+Ar)) of 0.2, RF power of 240W, substrate temperature of RT, annealing condition of 600$^{\circ}C$ for 20 min, and sputtering pressure of 20 mTorr.

A Study on the Relationship between Milk Consumption, Dietary Nutrient Intake and Physical Strength of Adolescents in Middle and Small-Sized Cities in Korea for Dietary Education of Home Economics Subject at Middle and High Schools (중등학교 가정교과 식생활교육을 위한 청소년의 우유 섭취, 영양 섭취 및 체력과의 관계 연구)

  • Kim, Sun-Hyo
    • Journal of Korean Home Economics Education Association
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    • v.28 no.4
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    • pp.159-167
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    • 2016
  • This study was performed to investigate the relationship between milk consumption, dietary nutrient intake, and physical strength in Korean adolescents for dietary education of home economics subject at middle and high schools. Intake of milk and milk products, that of dietary nutrients, and physical strength records were surveyed for 298 high school students resided in small and medium-sized cities in Korea. Intake of milk and milk products was collected from three-day dietary survey, and daily dairy equivalent of calcium was calculated by dividing daily calcium intake(mg) from milk and milk products by calcium content(200 mg) of 200 mL milk. Dietary survey was performed during three days including two-weekdays and one-weekend by food record method. Dietary nutrient intake was analyzed by CAN-Pro 3.0. Physical strength records were offered from subjects' schools. Subjects were divided into low intake group(${\leq}0.29/d$), medium intake group(0.30-0.78/d) and high intake group(0.79-5.66/d) according to daily mean dairy equivalent of calcium taken by them, and most of them consumed milk and milk products less than '2' of the recommended value. Daily mean dairy equivalent of calcium was significantly related with high records of '50 m running' and 'stand long jump'(p<0.05), however it was not related with other records of physical strength. Intakes of energy, carbohydrate, protein, fat, calcium, phosphorus, iron, zinc, thiamin, riboflavin, niacin and vitamin E were significantly correlated with high record of '50 m running'(p<0.01). Intakes of nutrients were related with '50 m running' except fat were significantly correlated with high record of 'stand long jump'(p<0.05). Intakes of protein, phosphorus, iron, zinc, vitamin A, $B_6$ and E were significantly correlated with high record of 'long distance running'(p<0.05). In conclusion intake of milk and milk products was related with physical strength records('50 m running' and 'stand long jump') and intakes of most nutrients including energy nutrient, vitamin and mineral were correlated with physical strength records('50 m running', 'stand long jump' and 'long distance running') in Korean adolescents. Therefore, optimal consumption of milk and various nutrients for balanced nutrition during adolescents should be emphasized in dietary education of home economics subject for their strong physical strength.

Optimization of Biotransformation Process for Sodium Gluconate Production by Aspergillus niger (Aspergillus niger를 이용한 글루콘산 나트륨 생산 생변환 공정의 최적화)

  • 박부수;조병관;이상윤;임승환;김동일;김병기
    • KSBB Journal
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    • v.14 no.3
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    • pp.309-314
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    • 1999
  • In order to produce high concentration of sodium gluconate, optimization of the fermentation conditions, such as glucose concentration, inoculum size, dissolved oxygen concentration and glucose feeding method, was examined. When the glucose concentration was maintained in the range of 30∼50 g/L during the batch fermentation, glucose conversion yield and productivity were 92.2% and 6.0 g/L/hr, respectively. In the case of the low concentration below 30 g/L, the yield decreased by about 25%. As the inoculum size increased above 20%(w/v), lag phase was shortened but the productivity decreased. The dissolved oxygen level of 60∼70% was shown to be the threshold point for 75% of increase in the productivity of sodium gluconate. Finally, optimal glucose feeding rate was determined using various feeding methods such as exponential feeding, feeding based on the average glucose consumption rate and was determined using various feeding methods such as exponential feeding, feeding based on the average glucose consumption rate and on the oxygen uptake rate and etc. Our result shows that glucose feeding, based on the oxygen uptake rate is a very simple, efficient and robust method, especially when oxygen is consumed as a substrate for the bioconversion. Using the above glucose feeding strategy under the optimized condition, 255 g/L of sodium gluconate concentration, 12 g/L/hr of productivity and 95% of glucose conversion yield were achieved with A. niger ACM53.

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Simultaneous Treatment of Carbon Dioxide and Ammonia by Microalgal Culture (조류배양을 통한 이산화탄소 및 암모니아의 동시처리)

  • ;;Bohumil Volesky
    • KSBB Journal
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    • v.14 no.3
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    • pp.328-336
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    • 1999
  • A green microalga, Chlorella vulgaris UTX 259, was cultivated in a bench-scale raceway pond. During the culture, 15%(v/v) $CO_2$ was supplied and industrial wastewater discharged from a steel-making plant was used as a culture medium. In a small scale culture bottle, the microalga grew up to 1.8 g $dm^{-3}$ of cell concentration and ammonia was completely removed from the wastewater with an yield coefficient of 25.7 g dry cell weight $g^{-1}\;NH_3-N$. During the bottle-culture, microalga was dominant over heterotrophic microorganisms in the culture medium. Therefore, the amount of carbon dioxide fixation could be estimated from the change of dry cell weight. In a semi-continuous operation of raceway pond with intermittent lighting (12 h light and 12 h dark), increase of dilution rate resulted in increase of the ammonia removal rate as well as the $CO_2$ fixation rate but the ammonia removal efficiency decreased. Ammonia was not completely removed from the medium (wastewater) of raceway pond which was operated in a batch mode under a light intensity up to 20 klux. The incomplete removal of ammonia was believed due to insufficient light supply. A mathematical model, capable of predicting experimental data, was developed in order to simulate the performance of the raceway pond under the light intensity of sun during a bright daytime. Simulation results showed that the rates of $CO_2$ fixation and ammonia removal could be enhanced by increasing light intensity. According to the simulation, 80 mg $dm^{-3}$ of ammonia in the medium could be completely removed if the light intensity was over 60 klux with a continuous lighting. Under the optimal operating condition determined by the simulation, the rates of carbon dioxide fixation and ammonia removal in the outdoor operation of raceway pond were estimated as high as $24.7 g m^{-2} day^{-1}$ and $0.52 g NH_3-N m^{-2} day^{-1}$, respectively.

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Trend (in 2005) of Repair of Inguinal Hernia in Children in Korea - A National Survey by the Korean Association of Pediatric Surgeons in 2005 - (2005년도 소아 서혜부 탈장치료 경향)

  • Kim, Seong-Min;Kim, Dae-Yeon;Kim, Sang-Yoon;Kim, Seong-Chul;Kim, Woo-Ki;Kim, Jae-Eok;Kim, Jae-Chun;Park, Kwi-Won;Seo, Jeong-Meen;Song, Young-Tack;Oh, Jung-Tak;Lee, Nam-Hyuk;Lee, Doo-Sun;Chun, Yong-Soon;Chung, Sang-Young;Chung, Eul-Sam;Choi, Kum-Ja;Choi, Soon-Ok;Han, Seok-Joo;Huh, Young-Soo;Hong, Jeong;Choi, Seung-Hoon
    • Advances in pediatric surgery
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    • v.12 no.2
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    • pp.155-166
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    • 2006
  • Inguinal hernia is the most common disease treated by the pediatric surgeon. There are several controversial aspects of management 1)the optimal timing of surgical repair, especially for preterm babies, 2)contralateral groin exploration during repair of a clinically unilateral hernia, 3)use of laparoscope in contralateral groin exploration, 4)timing of surgical repair of cord hydrocele, 5)perioperative pain control, 6)perioperative management of anemia. In this survey, we attempted to determine the approach of members of KAPS to these aspects of hernia treatment. A questionnaire by e-mail or FAX was sent to all members. The content of the questionnaire were adapted from the "American Academy of Pediatrics (AAP) Section on Surgery hernia survey revisited (J Pediatr Surg 40, 1009-1014, 2005)". For full-term male baby, most surgeons (85.7 %) perform an elective operation as soon as diagnosis was made. For reducible hernia found in ex-preterm infants already discharged from the neonatal intensive care unit (NICU), 76.2 % of surgeons performed an elective repair under general anesthesia (85.8 %). 42.9 % of the surgeons performed the repair just before discharge. For same-day surgery for the ex-premature baby, the opinion was evenly divided. For an inguinal hernia with a contralateral undescended testis in a preterm baby, 61.9 % of surgeons choose to 'wait and see' until 12 month of age. The most important consideration in deciding the timing of surgery of inguinal hernia in preterm baby was the existence of bronchopulmonary dysplasia (82.4 %), episode of apnea/bradycardia on home monitoring (70.6 %). Most surgeons do not explore the contralateral groin during unilateral hernia repair. Laparoscope has not been tried. Most surgeons do not give perioperative analgesics or blood transfusion.

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Density Dependent Growth of Scapharca satowi in the West Coast of Korea (큰이랑피조개 Scapharca satowi의 양성 밀도별 성장)

  • 송홍인;박광재;조영록;박영제
    • Journal of Aquaculture
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    • v.15 no.3
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    • pp.145-155
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    • 2002
  • Effect of density (30, 40, 65, 90 or 120/cage) of lantern and bottom cages on growth of the ark shell, Scapharca satowi was studied in the Korean west coast from April 2000 to October 2001, when the following range of environmental conditions prevailed : temperature : 4.2 -25.5 $^{\circ}C, salinity : 30.23-32.$15\textperthousand, dissolved oxygen : 5.12-7.16 $ml$/l, pH : 7.84-8.17, phosphate : 0.22-0.56 $\mu $M, dissolved inorganic nitrogen : 3.16-9.10 $\mu $M, suspended solid : 7.6-17.9 mg/l, chemical oxygen demand: 0.46-1.61 mg/l and chlorophyll-a : 0.92-5.93 $\mug/l. Daily growth rate of shell length ranged from 0.066 to 0.071 mm/day for the lantern net cages, and from 0.079 to 0.082 mm/day for the bottom cages. Total weight also ranged from 0.067 to 0.082 g/day in the lantern net cages, as against 0.099 to 0.114 g/day in the bottom cages. Hemoglobin content of S. satowi (55 mm shell length), which was about 3.9 g/dl during february, 2001, increased to 6.0 and 7.0 g/dl during October, 2001 in animals culture in the lantern and bottom cages, respectively. ANOVA test of the growth rate showed that the growth rate of S. satowi, was significantly dependent on rearing density and the tested culture methods (P < 0.0001). The daily growth rate of the shell length was more significantly correlated with water temperature; the growth rate of shell length and total weight showed a tendency decrease with decreasing temperature. In cages suspended at the bottom, not only the increase shell weight but also the meat obtainable from comparable sized S. satowi was greater. Survival decreased with increasing density and was optimal at the density of 30 individual/cage.

Polyculture of Fleshy Shrimp Fenneropenaeus chinensis and White Shrimp Litopenaeus vannamei with River Puffer Takifugu obscurus in Shrimp Ponds (축제식 양식장에서의 대하, 흰다리새우와 황복의 복합양식)

  • Jang, In-Kwon;Jun, Je-Cheon;Jo, Gook-Jin;Cho, Yeong-Rok;Seo, Hyung-Chul;Kim, Bong-Lae;Kim, Jong-Sheek
    • Journal of Aquaculture
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    • v.20 no.4
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    • pp.278-288
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    • 2007
  • Shrimp culture in Korea had been rapidly developed during 1990's and the production of farmed shrimp reached 3,268 mt from 2,605 ha in 2001. However the shrimp production decreased to 2,368 mt in 2004 because of the mass mortality due to outbreak of white spot syndrome virus (WSSV). WSSV which is one of the most serious threats associated with cultured shrimp around the world has given the economic damages to shrimp culture industry every year since it was found from the shrimp ponds in the west coast of the South Korea in 1993. Various polyculture technologies of shrimp with shellfish, finfish or seaweeds have been implemented to reduce economic damages by mass mortalities of shrimp. Among them, the polyculture of shrimp with carnivorous fish can suppress or delay the viral outbreak of shrimp ponds because the fish may selectively eat the moribund shrimps infected by virus. To determine the selective predatory effect of river puffer Takifugu obscures on WSSV infected shrimp, postlarvae of Litopenaeus vannamei and Fenneropenaeus chinensis. One-year old river puffers were stocked to four earthen ponds of $1,616-1,848\;m^2$ in surface area as followings: polyculture LvP, L. vannamei ($43.4/m^2$)+puffer ($0.22/m^2$); control Lv, L. vannamei ($46.9/m^2$); polyculture FcP, F. chinensis ($30.3/m^2$)+puffer ($0.25/m^2$); control Fc, F. chinensis ($24.6/m^2$). Ponds of control Fc and polyculture FcP had mass mortalities by WSSV outbreak on the $51^{st}$ and $57^{th}$ days of culture respectively. The shrimps of polyculture LvP and control Lv were harvested on the $95^{th}\;day$. Shrimp survival rates of polyculture LvP and control Lv were 32.4% and 18.2% respectively and shrimp productivity of polyculture LvP was 69.2% higher than that of control Lv. Concentration of nutrients (TAN, $NO_2-N$, $NO_3-N$) was maintained within optimal ranges for shrimp growth although that of polyculture ponds showed at least two times higher than that of control ponds. The results suggest that polyculture of L. vannamei with river puffer is higher than monoculture in survival rate and productivity. In addition, F. chinensis should be carefully cultured because this species shows much higher susceptibility to WSSV than L. vannamei.

The Design of Smart-phone Application Design for Intelligent Personalized Service in Exhibition Space (전시 공간에서 지능형 개인화 서비스를 위한 스마트 폰 어플리케이션 설계)

  • Cho, Young-Hee;Choi, Ae-Kwon
    • Journal of Intelligence and Information Systems
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    • v.17 no.2
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    • pp.109-117
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    • 2011
  • The exhibition industry, as technology-intensive, eco-friendly industry, contributes to regional and national development and enhancement of its image as well, if it joins cultural and tourist industry. Therefore, We need to revitalize the exhibition industry, as actively holding an exhibition event. However, to attract a number of exhibition audience, the work of enhancing audience satisfaction and awareness of value for participation should be prioritized after improving quality of service within exhibition hall. As one way to enhance the quality of service, it is thought that the way providing personalized service geared toward each audience is needed. that is, if audience avoids the complexity in exhibition space and it affords them service to enable effective time and space management, it will improve the satisfaction. All such personalized service affordable lets the audience's preference on the basis of each audience profile registered in advance online grasp. and Based on this information, it is provided with exhibition-related information suited their purpose that is the booth for the interesting audience, the shortest path to go to the booth and event via audience's smart phone. and it collects audience's reaction information, such as visiting the booth, participating the event through offered the information in this way and location information for the flow of movement, the present position so that it makes revision of existing each audience profile. After correcting the information, it extracts the individual's preference. hereunder, it provides recommend booth and event information. in other words, it provides optimal information for individual by amendment based on reaction information about recommending information built on basic profile. It provides personalized service dynamic and interactive with audience. This paper will be able to provide the most suitable information for each audience through circular and interactive structure and designed smart-phone application supportable for updating dynamic and interactive personalized service that is able to afford surrounding information in real time, as locating movement position through sensing. The proposed application collects user‘s context information and carrys information gathering function collecting the reaction about searched or provided information via sensing. and it also carrys information gathering function providing needed data for user in exhibition hall. In other words, it offers information about recommend booth of position foundation for user, location-based services of recommend booth and involves service providing detailed information for inside exhibition by using service of augmented reality, the map of whole exhibition as well. and it is also provided with SNS service that is able to keep information exchange besides intimacy. To provide this service, application is consisted of several module. first of all, it includes UNS identity module for sensing, and contain sensor information gathering module handling and collecting the perceived information through this module. Sensor information gathered like this transmits the information gathering server. and there is exhibition information interfacing with user and this module transmits to interesting information collection module through user's reaction besides interface. Interesting information collection module transmits collected information and If valid information out of the information gathering server that brings together sensing information and interesting information is sent to recommend server, the recommend server makes recommend information through inference with gathered valid information. If this server transmit by exhibition information process, exhibition information process module is provided with user by interface. Through this system it raises the dynamic, intelligent personalized service for user.

Mobile Contents Transformation System Research for Personalization Service (개인화 서비스를 위한 모바일 콘텐츠 변환 시스템 연구)

  • Bae, Jong-Hwan;Cho, Young-Hee;Lee, Jung-Jae;Kim, Nam-Jin
    • Journal of Intelligence and Information Systems
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    • v.17 no.2
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    • pp.119-128
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    • 2011
  • The Sensor technology and portable device capability able to collect recent user information and the information about the surrounding environment haven been highly developed. A user can be made use of various contents and the option is also extending with this technology development. In particular, the initial portable device had simply a call function, but now that has evolved into 'the 4th screen' which including movie, television, PC ability. also, in the past, a portable device to provided only the services of a SMS, in recent years, it provided to interactive video service, and it include technology which providing various contents. Also, it is rising as media which leading the consumption of contents, because it can be used anytime, anywhere. However, the contents available for the nature of user's handheld devices are limited. because it is very difficult for making the contents separately according to various device specification. To find a solution to this problem, the study on one contents from several device has been progressing. The contents conversion technology making use of the profile of device out of this study comes to the force and profile study has been progressing for this. Furthermore, Demand for a user is also increased and the study on the technology collecting, analyzing demands has been making active progress. And what is more, Grasping user's demands by making use of this technology and the study on the technology analyzing, providing contents has been making active progress as well. First of all, there is a method making good use of ZigBee, Bluetooth technology about the sensor for gathering user's information. ZigBee uses low-power digital radio for wireless headphone, wireless communication network, and being utilized for smart energy, automatic home system, wireless communication application and wireless sensor application. Bluetooth, as industry standards of PAN(Personal Area Networks), is being made of use of low power wireless device for the technology supporting data transmission such as drawing file, video file among Bluetooth device. With analyzing the collected information making use of this technology, it utilizes personalized service based on network knowledge developed by ETRI to service contents tailor-made for a user. Now that personalized service builds up network knowledge about user's various environments, the technology provides context friendly service constructed dynamically on the basis of this. The contents to service dynamically like this offer the contents that it converses with utilizing device profile to working well. Therefore, this paper suggests the system as follow. It collects the information, for example of user's sensitivity, context and location by using sensor technology, and generates the profile as a means of collected information as sensor. It collects the user's propensity to the information by user's input and event and generates profile in the same way besides the gathered information by sensor. Device transmits a generated profile and the profile about a device specification to proxy server. And proxy server transmits a profile to each profile management server. It analyzes profile in proxy server so that it selects the contents user demand and requests in contents server. Contents server receives a profile of user portable device from device profile server and converses the contents by using this. Original source code of contents convert into XML code using the device profile and XML code convert into source code available in user portable device. Thus, contents conversion process is terminated and user friendly system is completed as the user transmits optimal contents for user portable device.

Quality of Yellow Poplar (Liriodendron tulipifera) Seedlings by the Method of Seedling Production (백합나무 양묘방법에 따른 묘목품질 비교)

  • Ryu, Keun-Ok;Song, Jeong-Ho;Choi, Hyung-Soon;Kwon, Hae-Yun;Kwon, Yong-Rak
    • Journal of Korean Society of Forest Science
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    • v.96 no.3
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    • pp.307-316
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    • 2007
  • Yellow poplar (Liriodendron tulipifera L.) has low germination rate relatively other species, so the seedling production of Yellow poplar is a hard task. Accordingly this study was conducted to determine the optimal germination conditions for healthy seedling production and to promote survival rate after afforestation. Gemination percentage was examined at different media and seed covering materials using planting flats in the greenhouse. The best germination percentage was observed in sand for media and compound soil for covering materials. But it was time to transplant, seedlings became a poor character (i.e. height, root length, number of root, dry weight) in sand for media. In order to produce healthy seedlings, each different medium was compounded with TKS-2 (this is a gardening bed soil.) in the ratio 1:1 (v/v.), and compared two conditions. Quality of seedling was better than not mixed TKS-2 into each medium. Transplanting seedlings from greenhouse to nursery grew up rapidly 2 months later (early in August~early in October). Growth amount during two months corresponded to 85.6% and 71.3% in total growth amount of height and diameter at root collar, respectively. In the case of the competition-density effect on yellow-poplar seedlings, direct seedling produced the maximum 35 standard seedlings above 8 mm of root collar diameter per $m^2$, while transplanting seedling produced the maximum 64 standard seedlings per $m^2$. And produced seedlings of two way were significantly different rootlet while axial root and lateral root was not significantly different.