• Journal of Forest and Environmental Science
• /
• 제34권3호
• /
• pp.209-223
• /
• 2018

We investigated tree composition, stand characteristics, biomass allocation pattern and carbon storage variability in Sal forests (Shorea robusta Garten.) under two forest management regimes (Sal forest and Sal plantation) in Tripura, Northeast India. The results revealed higher species richness (29 species), stand density of $1060.00{\pm}11.12stems\;ha^{-1}$ and diversity index ($1.90{\pm}0.08$) in Sal forest. and lower species richness (4 species), stand density of $ 230.00{\pm}37.22stems\;ha^{-1}$ and diversity index ($0.38{\pm}0.15$) in Sal plantation. The total basal cover $33.02{\pm}4.87m^2ha^{-1}$) and dominance ($0.76{\pm}0.08$) were found higher in Sal plantation than the Sal forest ($22.53{\pm}0.38m^2ha^{-1}$ and $0.23{\pm}0.02$ respectively). The total vegetation carbon density was recorded higher in Sal plantation ($219.68{\pm}19.65Mg\;ha^{-1}$) than the Sal forest ($167.64{\pm}16.73Mg\;ha^{-1}$). The carbon density estimates acquired in this study suggest that Sal plantation in Tripura has the potentiality to store a large amount of atmospheric carbon inspite of a very low species diversity. However, Sal forests has also an impending sink of carbon due to presence of large number of young trees.

• 한국작물학회지
• /
• 제50권1호
• /
• pp.45-54
• /
• 2005

This study was carried out to investigate the patterns of dry matter (DM) production and accumulation, and to screen the relationships between related major growth characters and DM accumulation in four cassava varieties in Bogor $(6^{\circ}19'-6^{\circ}47'S,\;106^{\circ}21'-107^{\circ}13'E)$, West Java, Indonesia. Gading and Adiral developed an enough source and canopy in short at the early growth phase and then translocated assimilates to storage roots with a higher partitioning rate, even these varieties were considered as early-bulking varieties, which have superior source and sink potentials in increasing yield and DM of tubers. The root/shoot ratio (R/SR), total dry weight (TDW), leaf area duration, leaf area index (LAI), and number of tubers showed higher positive correlations with the dry weight of roots (DWR), and the direct effects of TDW, R/SR, and LAI on the DWR were higher. These characters were considered to be useful target characters to screen cassava varieties with high yield potential and high DM in aspect of tuber production.

• 대한전기학회논문지
• /
• 제45권3호
• /
• pp.341-351
• /
• 1996

The values for the average and rms currents in a three-level PWM inverter are required in order to select the various components such as power semiconductor devices, capacitors and reactors of inverter circuit. And those are very useful for the designing of the heat sink. In this paper, therefore, the simple current equations are proposed for a three-level PWM inverter. Analysis of inverter current waveforms indicate that the average and rms inverter currents are dependent on the load power factor and PWM modulation index (Ma). Error analysis and experiment results verify the effectiveness of the proposed current equations. (author). refs., figs., tabs.

• 한국작물학회지
• /
• 제45권2호
• /
• pp.97-102
• /
• 2000

This experiment was conducted to investigate the changes of harvest index and the relationship between harvest index and yield determination factors by different planting times in the determinate soybean cultivars, Shinpaldal and Danbaeg. Optimum planting were 23 May in 1995 and 1996. Late planting were 13 June in 1995 and 6 June in 1996. Growth period from planting to physiological maturity (R7) was shortened as planting time was delayed in two cultivars due to shortening of reproductive growth period in Shinpaldal, and of vegetative growth period in Danbaeg. Stem weight was distinctly decreased in late planting compared to optimum planting, but seed weight of both cultivars was not different between planting times. Also, seed number per pod and harvest index were significantly increased in late planting and the high correlation was found between two factors. It was suggested that increase of harvest index in late planting would be related with high assimilate use efficiency due to increase of sink capacity. The results of correlation and principal component analysis for yield determination factors showed that main factor on yield determination was pod number per plant at R5 stage associated with dry matter accumulation during early reproductive growth period, seed number per pod and harvest index were the second factor, and one hundred seed weight was the third factor. The result of this experiment indicated that yield determination in soy-bean was dependent mainly on pod number per plant related to dry matter accumulation by early reproductive growth period, and the increase of seed number per pod and harvest index could compensate for yield decrease by shortening of vegetative growth period in late planting. Such result suggests that optimum planting date can be delayed from mid May to early June in improved soybean cultivars in Korea.

• 한국작물학회지
• /
• 제50권5호
• /
• pp.301-308
• /
• 2005

This study was carried out to investigate the effect of stem-cutting (SC) length and portion on the major agronomic characters related with dry matter production and accumulation, and to examine their relation­ships in cassava. When cassava was planted with longer SCs or with older portion SCs, major canopy or source characters like leaf number and leaf area index developed excessively, while tuber yields could be reduced due to the decrease of root/shoot ratio, relative growth rate, root dry weight, and harvest index, particularly in the bitter varieties (high cyanide-level varieties). It was considered that the sweet varieties (low cyanide-level varieties) be early­bulked with higher tuber yield when they are planted with the 25-30 cm long SCs or with the SCs from young type to semi-mature portions of mother stems, while the bitter varieties with the 15-20 cm long SCs or with the SCs from semi-mature to hardwood portions of mother stems, respectively. However, a significant interaction between length and portion of SC was not observed in all agronomic characters.

• 환경영향평가
• /
• 제19권6호
• /
• pp.607-615
• /
• 2010

Urban green space is often at the centre of the debate on urban substantiality because it provides functions of space, e.g. for wildlife, recreation, growing vegetables, psychological wellbeing, social interaction, etc. Traditionally, the various functions of urban green spaces clearly show that green spaces contain important values that contribute to the overall quality of urban life. After Kyoto protocol, it has becoming important to more accurately evaluate carbon uptake by urban green space. Many studies have analyzed the benefits, costs, and carbon storage capacity associated with urban green space. These studies have been limited by a lack of research on urban tree biomass and carbon uptake by soil, such that estimates of carbon storage in urban systems. This study calculate more accurately the amount of carbon uptake by urban green space. This study also complement the existing methods to estimate the urban green space carbon uptake. It has been studied how to evaluate carbon uptake function of urban green space. The surface area of urban green space increased 5% by complemented method and carbon uptake is also increased. Based on this result, the carbon uptake per capita was analysed and compared to the area of carbon uptake. And this study discussed the reasons for the differences between the new and earlier estimates, as well as implications for our understanding of the global carbon cycle. In conclusion, these results could contribute as preliminary data to policy makers when climate change adaptation strategy is established.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.1724-1727
• /
• 2005

Injection molding process is one of the processes that can mold plastic product as low cost. However, manufacturing process of automobile bumper mold has lots of trial and error. Especially, desiging of a huge mold such as bumper mold is needed to establish a design standard for runner system. In this study, CAE was conducted to observe the variation of melt-flow by changing runner and gate type in automobile bumper mold as preceding study for a standard design of runner system.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2004년도 춘계 학술대회지
• /
• pp.290-291
• /
• 2004

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2004년도 춘계 학술대회지
• /
• pp.70-71
• /
• 2004

• 한국지반공학회지:지반
• /
• 제2권1호
• /
• pp.27-44
• /
• 1986

기초 구조물 설계에 있어서 지지력 및 압밀 침하량 산정식을 각각 단일 모우드 거동함수(perfor trance function)로 설정하여 실측된 토성자초를 확률변수로 취해서 기술류계학적 분석을 기행했다. 이 분석결과로서 얕은 기초가 파괴상태에 이르렀을 때의 신뢰도와 그 때에 거동되고 있는 설계변수치(check points)를 "Advanced first-order second moment method"로 구했다. 설계변수들 사이의 관계를 무연관-정규분포, 무상관-비정규분포, 유상관-정규분포 및 유상관-비정규분포 등의 유형 으로 분류하여 신뢰도 및 설계변수치를 비교 검토하여 얻은 주요한 결론은 다음과 같다. 1. 지지력 모우드 1) CU test 의한 점착력과 tans사이에는 약한 음상관치 있으며, 각각 대규분포 및 대수정륜 분포를 한다. 2) 신뢰지수를 2.34로 제한했을 경우, 유상관-대수정규분포 유형의 지지력은 18.6t/m2으로서 가장 낮게 되므로, 이 이외의 유형은 지반조건을 과대평가할 우려가 있다. 2. 압밀 침하량 모우드 1) 압축비(compression ratio) 및 선행 압밀응력은 각각 정규분포 및 대수정규분포를 이루며, 이들의 상관성은 연계적 독립변수로 취급해도 좋을 만큼 매우 낮다. 2) 압밀 침하량을 확정론적 방법으로 산출한 16cm보다 더 낮게 취하면, 유상관일대수정규분포류 형의 신뇌맥가 가장 낮게 평가된다. 따라서, 얕은 기초 구조물을 신뇌도나 파괴확률을 해석하는 데 있어서, 정확한 확률밀도함수로서 복잡한 수치적분에 의한 엄밀해보다는 개략적인 확률분포형태와 비교적 쉽게 얻어지는 공분산까지를 고려하면, 기초의 지반조건이 과소평가될 우려가 없다.가될 우려가 없다.의 뽕밭에 발생한 발아불량현상의 원인은 주인이 저온에 의한 동해라고 볼 수 있으며 지역적으로는 붕소결핍에 의한 발아불량현상도 적지 않았고 특히 붕소결핍이 동해피해를 가속화시켰다고 볼 수 있다.dard deviation)were estimated, and diagram which shows the relationship between mean annual maximum rainfall($$) and frequency factor for each durations were drawn. PMP was estimated by statistical method using the PMP frequency factor obtained from the diagram and statistics($$, Sn). The PMP-Duration Equation was derived from the envelope curve in order to obtain the PMP for an arbitrary duration. The isohyetal map of 24 hours PMP and PMP. DAD curve for the whole of Korea were drawn in accordance with the point PMP values.el size는 거의 차이가 없었는데, 특히 수당영화수 및 sink용량에 대한 주연효과정도는 계통에 따라 상당한 차이를 보였다. 계통의 자체경쟁정도는 출수후보다는 출수전 생식생장기간에 더욱 심하고 계통간차이도 큰 것 같았다. 일반적으로 수당sink용량이 클수록 출수전 자체경쟁정도가 심한 경향이었으나 계통에 따라서는 수당 sink용량이 작으면서 자체경쟁도가 심한 것(수원264호 등)이