Cone Length Research Articles

Effect of inner secondary air cone length of a centrally fuel‐rich swirl burner on combustion characteristics and NOx emissions in a 0.5 MW pulverized coal‐fired furnace with air‐staging

AbstractLow NOx burners and air staging technology are the most economic and effective means of reducing NOx emissions from coal‐fired furnaces. However, it is difficult to significantly reduce NOx emissions through air‐staged combustion in the furnace without reducing the boiler efficiency. The aim of this work was to study the effect of the inner secondary air cone length of a centrally fuel‐rich swirl coal combustion burner on combustion and NOx characteristics using a 0.5 MW laboratory furnace with air‐staging. Gas temperature and concentrations of gaseous species (O2, CO, and NOx) were measured in the primary combustion and burnout zones for different inner secondary air cone lengths. It was found that the inner secondary air cone length had significant effects on NOx emissions, unburned carbon content in the fly ash, and ignition performance of the burner. As the inner secondary air cone length increased, the unburned carbon content in the fly ash level increased, NOx emissions decreased, and pulverized‐coal ignition occurred later. The optimized results provide an important reference for engineering design. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd.

Variability in cone, seed and seedling characteristics of Pinus kesiya Royle ex. Gordon

Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone, seed and seedlings of 17 plus trees (PTs) of Pinus kesiya growing in eastern Himalayas (Meghalaya state) of India. The significant variations has been observed in cone weight, cone length, cone diameter, seed length, seed diameter, seed weight, number of seeds per cone, seed germination, seedling height and seedling collar diameter among different PTs of the species. Significant positive correlation (p 75) coupled with maximum genetic gain. Traits with such values indicate the presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that PTs expressed both phenotypic and genotypic differences in the seed, cone and seedling characters, which may be attributed to the differences in genetic makeup of various PTs and environmental factors i.e. genotypic and environmental interaction. The presence of high variability in P. kesiya PTs for different characters provide further opportunities to improve the population in subsequent generations so as to establish this species as an important timber tree to be grown on less fertile and degraded soils in its distributional ranges.

FEM Analysis and Structure Improvement of Pinch Valve

Pinch valve is an important flow adjusting device in the operating system of polymer materials with characteristics of high viscosity and high solid content, and its service life limits its application and popularization. In this study, for the special application environment and requirements of clevis pinch valve in the operating system, the dual-parameter Mooney-Rivlin constitutive model of rubber and Linear Elastic model of clevis were used. The stress and strain distributions of the rubber hose, while completely closed, were obtained by means of FEM (Finite Element Method) analysis. Parameters of hose thickness and cone length of the rubber hose were optimized, and the structure-improved pinch valve was obtained as well. The strain energy release rate and fatigue life were analyzed for the improved rubber hose at the most dangerous cell.

Field evidence from Namibia does not support the designation of Angolan and Namibian subspecies of Welwitschia mirabilis Hook

Welwitschia mirabilis is an ancient, endemic gymnosperm found in numerous disjunct populations in western Namibia north of the Namib Sand Sea to the Bentiaba River in southwestern Angola. Based on six plants grown in the Berlin-Dahlem Botanical Garden, Leuenberger [2001, Welwitschia mirabilis (Welwitschiaceae), male cone characters and a new subspecies. Willdenowia 31: 357–381] differentiated two groups of plants using eight male inflorescence characters. He concluded that the two groups represented geographical subspecies: W. mirabilis subsp. mirabilis in Angola and W. mirabilis subsp. namibiana in Namibia, based on putative location data of the seed sources for the plants. Leuenberger called for field data collection, especially in northern Namibia, to verify his results. However despite this lack of data, numerous authors have cited his work as definitive in scientific papers and online plant descriptions and keys. We analysed five distinguishing male cone characters from 13 Namibian plant populations and found significant variation that encompasses both descriptions of the Namibian and Angolan subspecies. Data collected from plants grown from Angolan and Namibian seed in the Kirstenbosch Botanical Garden also fell within the range of the Namibian field populations. We found significant evidence of latitudinal gradients in cone and peduncle length, but cone colour, secondary branch length and bract shape were highly variable within and between the Namibian populations sampled. Our data do not support the designation of an Angolan and Namibian subspecies. W. mirabilis has probably been evolving in this landscape for more than 100 million years with unknown metapopulation dynamics predetermining current geographical populations. Our study calls for molecular characterisation in conjunction with a thorough investigation of both male and female plant characteristics throughout the current range of the plant to further clarify the phylogenetic relevance of the variation observed in male cone characters.

Pilot-scale Studies of Ash and Sulfur Removal from Fine Coal by Using the Cylojet Flotation Cell

This article presents the results of pilot-scale studies of ash and sulfur removal from a Turkish coal by using the cyclojet flotation cell. The cyclojet cell, which was developed by H. Hacifazlioglu and I. Toroglu in 2006, utilizes an alternative jet flotation technique. Apart from being based on the working principle of jet flotation, the cyclojet cell incorporates centrifugal forces into the flotation process, thus providing an excellent separation for ash and pyritic sulfur removal. The most important parameters for the removal of ash and pyritic sulfur in the cycojet cell are the length of the conical jet, frother type, wash water rate, and froth thickness. With decreasing the conical jet length and increasing the wash water rate and froth thickness, there is an increase in the removal of pyritic sulfur. On the other hand, the frothing agents MIBC produced better results in terms of pyritic sulfur removal in the cyclojet cell. Under optimal conditions, the cyclojet cell removed 61.25% of the pyritic sulfur and 73.98% of the ash with a combustible recovery value of 71.10% without any need for a depressant.

Influence of fiber paths on buckling load of tailored conical shells

The purpose of this paper is to propose a method for evaluation of varying stiffness coefficients of tailored conical shells (TCS). Furthermore, a comparison between buckling loads of these shells under axial load with the different fiber path is performed. A circular truncated conical shell subjected to axial compression is taken into account. Three different theoretical path containing geodesic path, constant curvature path and constant angle path has been considered to describe the angle variation along the cone length, along cone generator of a conical shell are offered. In the TCS with the arbitrary fiber path, the thickness and the ply orientation are assumed to be functions of the shell coordinates and influencing stiffness coefficients of the structure. The stiffness coefficients and the buckling loads of shells are calculated basing on classical shells theory (CST) and using finite-element analysis (FEA) software. The obtained results for TCS with arbitrary fiber path, thickness and ply orientation are derived as functions of shell longitudinal coordinate and influencing stiffness coefficients of structures. Furthermore, the buckling loads based on fiber path and ply orientation at the start of tailored fiber get to be different. The extent of difference for tailored fiber with start angle lower than 20 degrees is not significant. The results in this paper show that using tailored fiber placement could be applied for producing conical shells in order to have greater buckling strengths and lower weight. This work demonstrates the use of fiber path definitions for calculated stiffness coefficients and buckling loads of conical shells.

Pressure Flushing of Cohesive Sediment in Large Dam Reservoirs

AbstractPressure flushing of deposited sediments behind large dam walls causes development of a funnel-shaped crater due to the induced vortex and considerable shear flow around the outlets. Laboratory experiments were conducted to investigate interaction of flow and sediment parameters on the development and final size of the scour cone. The volume of the flushed sediment increases with increase of discharge, and decreases with increase of sediment bulk density and the water level above the sediment. While the water depth over the sediments is the most significant parameter in the collapse of sediments above the intake and the initial development of the cone, sensitivity analysis indicated bulk density of cohesive sediment to be the most effective parameter to determine the final size of the scour cone. Using experimental results, two equations were developed to estimate scour cone volume and length with readily defined and measurable parameters of flow and sediment. The field measurements confirm the ca...

Simulation of Taper Roll Deviation Rectification Ability in Continuous Annealing Furnace

Running deviation of cold strip affects smooth operation in continuous annealing furnace, and the taper roll technology has positive significance for the prevention of strip deviation. In this paper, a finite element model of cold strip in continuous annealing furnace is established, and it can be used to analysis deviation rectification ability of single taper roll with different conical height and straight section length, double taper roll with different total conical height, straight section length and taper ratio. The calculation results show that the conical height is the most important factor for deviation rectification, and the deviation rectification ability of double taper roll is better than single taper roll. The results provide reference for taper roll optimization design in continuous annealing furnace.

고속 선회류 침전 장치의 유동 해석 및 수질 개선을 위한 현장 적용 가능성 평가

본 연구는 오염된 유수지 수질개선을 위한 고속 선회류 침전 장치(HRSC)의 이용 가능성을 평가하는데 목적을 두었다. 이를 위해 실험실 규모 및 파일럿 규모의 실험을 수행하였다. 또 전산유체역학(CFD) 프로그램 중 하나인 Fluent를 이용하여 유입속도 및 유입직경, 몸체길이(<TEX>$L_B$</TEX>) 및 하부콘길이(Lc), 역경사콘 기울기 및 간격, 하부유출홀 설치 여부가 HRSC 장치내부의 유체흐름 패턴에 미치는 영향을 분석하였다. 유동 분석 결과와 실험실 규모의 실험 결과를 토대로 파일럿 장치를 제작하고 유수지 시료를 대상으로 현장 적용 가능성을 평가하였다. 장치 내부의 유동 조사 결과, 유입 유량과 직경 보다 유입 속도가 선회류 형성에 더 큰 영향을 나타내었으며, <TEX>$L_B$</TEX> <TEX>$1.2{\sim}1.6D_B$</TEX>(몸체 직경), Lc <TEX>$0.35{\sim}0.5L_B$</TEX> 범위에서는 큰 차이가 없었으나 <TEX>$L_B/D_B$</TEX> 2.0, <TEX>$Lc/L_B$</TEX> 0.75로 비가 큰 경우 선회류는 감소되었다. 역경사콘 기울기가 커질수록 역경사콘 내부 속도는 낮아지고 매우 균일하게 분포되었으며, 역경사콘 간격은 난류를 방지하기 위해 10cm가 20cm 보다 좋은 조건이었다. 하부 유출홀은 설치하지 않는 것이 배출수의 고른 유량 분배와 편류 방지를 위해 보다 좋은 것으로 판단되었다. 파일럿 규모의 현장 실험 결과 수중의 입자성 물질이 효과적으로 제거되어 본 장치가 유수지와 같은 대용량 수체의 수질개선을 위한 한 가지 방안으로 활용될 수 있을 것으로 기대되었다. The purpose of this study is to evaluate the High Rate Spiral Clarifier(HRSC) availability for the improvement of polluted retention pond water quality. A lab scale and a pilot scale test was performed for this. The fluid flow patterns in a HRSC were studied using Fluent which is one of the computational fluid dynamic(CFD) programs, with inlet velocity and inlet diameter, length of body(<TEX>$L_B$</TEX>) and length of lower cone(Lc), angle and gap between the inverted sloping cone, the lower exit hole installed or not installed. A pilot scale experimental apparatus was made on the basis of the results from the fluid flow analysis and lab scale test, then a field test was executed for the retention pond. In the study of inside fluid flow for the experimental apparatus, we found out that the inlet velocity had a greater effect on forming spiral flow than inlet flow rate and inlet diameter. There was no observable effect on forming spiral flow LB in the range of 1.2 to <TEX>$1.6D_B$</TEX>(body diameter) and Lc in the range of 0.35 to <TEX>$0.5L_B$</TEX>, but decreased the spiral flow with a high ratio of <TEX>$L_B/D_B$</TEX> 2.0, <TEX>$Lc/L_B$</TEX> 0.75. As increased the angle of the inverted sloping cone, velocity gradually dropped and evenly distributed in the inverted sloping cone. The better condition was a 10cm distance of the inverted sloping cone compared to 20cm to prevent turbulent flow. The condition that excludes the lower exit hole was better to prevent channeling and to distribute effluent flow rate evenly. From the pilot scale field test it was confirmed that particulate matters were effectively removed, therefore, this apparatus could be used for one of the plans to improve water quality for a large water body such as retention ponds.

Three-dimensional and experimental investigation on the effect of cone length of throttle valve on thermal performance of a vortex tube using k–ɛ turbulence model

Energy separation procedure of vortex tube can be improved by using truncated cone throttle valve. Experiments are performed to study the effect of the geometrical parameters on vortex tube refrigeration capacity by using air as the working fluid. In this experimental investigation, the parameters are focused on the cone length of throttle valve, inlet pressure and number of nozzle intakes. The effect of the cone length of throttle valve is also investigated in the range from 0 to 10 mm. The results present that there is an optimum cone length for obtaining the highest efficiency and φ = 6 mm is the optimal candidate under our experiments. The most objective of this investigation is the demonstration of the successful use of CFD in order to develop a design tool that can be utilized with confidence over a range of operating conditions and geometries, thereby providing a powerful tool that can be employed to optimize vortex tube design as well as assess its utility in the field of new applications and industries. A computational fluid dynamics model was developed to predict the performances of the vortex tube system. The numerical investigation was carried out by full 3D steady state CFD-simulation using FLUENT 6.3.26. This model utilizes the k–ɛ turbulence model to solve the flow equations.

Phenotypic variations in cones and seeds of natural Pinus kesiya var. langbianensis populations in Yunnan Province, China

Aims Our objectives were to determine phenotypic variations in 11 natural Pinus kesiya var. langbianensis populations and their relationship with distributions. Methods We investigated 16 phenotypic traits for 330 individuals in 11 natural populations of P. kesiya var. langbianensis in Yunnan Province, and used nested analysis, variation coefficient, correlation analysis, and un-weighted pair-group method using arithmetic averages(UPGMA) cluster analysis to analyze results. Important findings There are significant differences in phenotypic variation among and within populations. Variation is greater within populations(54.76%) than among populations(10.44%). Mean phenotypic differentiation coefficient is 11.95% among populations. Differentiations among populations are relatively small. The average variation coefficient of seed weight is highest(35.51%), followed by cone weight(35.1%); the average variation coefficient of seed size is smallest(8.86%). The seed size is the most stable phenotypic traits. Phenotypic diversity is greatest in Jinggu County and smallest in Jinghong City. There are significant or highly significant correlations among most phenotypic traits in cones and seed, indicating that greater the cone length and cone weight, larger the seed scales, seed size, seed wing, 1 000 seeds weight, and the number of seed scales and seeds per cone. The mean annual temperature appears to be the most prominent ecological factor influencing phenotypic traits, followed by the January mean temperature and growing degree days at 5 °C. According to UPGMA cluster analysis, the 11 populations can be divided into two groups and four subgroups due to difference in geographic distance, which is significantly related to annual precipitation and growing degree days at 5 °C.

Analysis of the Flow Field and Structure Optimization in Gas-Liquid-Solid Three-Phase Hydrocyclone

The flow field of gas-liquid-solid three-phase hydrocyclone was analyzed by using the software FLUNET. We have researched different structural parameters on the effect of degassing and degritting. The result shows that the change of inverted cone length ratio, inverted cone diameter, the form of liquid outlet hole structure and the angle of vent structure have some influence on degassing and degritting. Simulation results provides a good technical support for the optimization design of three-phase hydrocyclone structure.

Intrapopulational variability of Pinus sylvestris L. from Piekielna Góra in respect to cone and needle traits

From 37 Scots pine trees in Piekielna Góra the two-year old cones were collected and studied in respect to 14 morphological traits including the setting angle. One-year old cones from the same trees were examined in respect to their setting angle only. The data obtained for two-year old cones were subject to a whole range of multivariate analytical methods, to detect variability between randomly selected trees. Discriminant analysis was performed, Mahalanobis distances between each pair of trees were calculated and their significance was estimated using the Hotelling T&lt;sup&gt;2&lt;/sup&gt; statistics. A minimum spanning tree was constructed on the basis of the shortest Mahalanobis distances while Euklidean distances served to perform cluster analysis. The randomly selected sample of Scots pine population did not show any internal, significantly differentiated groups and variability among the trees was low. Cone dimensions belonged to the most variable traits, but the ratio of cone length to cone width showed the lowest variability. The extensive similarity of the population to the other earlier examined populations of &lt;i&gt;Pinus sylvestris&lt;/i&gt; L. from the Kłodzko District, and certain divergencies from the population are demonstrated.

Juvenile radiata pine clonal seed orchard management in Galicia (NW Spain)

A juvenile radiata pine clonal seed orchard (Pinus radiata D. Don) in Sergude (northwestern Spain), comprising 57 clones, was evaluated for fertility, offspring diversity and genetic drift during 4 years. Flower and fruit production was used to asses clone fertility in the orchard. Fertility variation measured as “sibling coefficient” was found to be an average of 1.5, having high genetic diversity (0.99) and low coancestry (0.013). The clones varied in fertility from year to year. Effective population size in the orchard was between 35 and 40, indicating that between 60.30 and 69 %, the clones contributed effectively to seed yield. One way to improve seed yield in the orchard is by increasing the effective population size. Thinning and pruning highly reproductive clones of gibberellin application might be useful in increasing effective population size. The orchard’s parental balance showed consistent improvement over time. Cone and seed characteristics were also investigated. The results showed that significant genetic variation exists among clones for cone width and length; total, sound and empty seed number; as well as 100 seed weight. The seed orchard is still in a juvenile phase; moreover, the broad-sense heritability and variation data obtained in this study could be very valuable in the management practices of the existing radiata pine clonal seed orchard and can be also used for better planning of advanced generation of clonal seed orchards in Spain.

Optimizing Design of Accessories for High-Voltage XPLE Power Cables

This paper describes the optimization design of prefabricated XPLE cable accessories and presents the formula of the design of stress cone. The finite element method for optimizing the design of the electric stress distribution inside the HV power cable joint and adjusting the length and curvature of the stress cone of this termination is discussed. The relationships between dimensions of stress cones structure and the electric field distribution were obtained.

Экспериментальное исследование влияния длины конической камеры смешения и горловины диффузора на характеристики сверхзвукового газового эжектора

Экспериментальное исследование влияния длины конической камеры смешения и горловины диффузора на характеристики сверхзвукового газового эжектора

Neural network estimation of the scour cone geometry around outlet in the pressure flushing

When flushing carry out as pressure condition, a scour cone is performed around the outlet. As the flow around the outlet in the pressure flushing is three dimensional, therefore that it is difficult to establish a general empirical model to provide accurate estimation for scour cone volume and length. In this study artificial neural network (ANN) with multi-layer perception which using backpropagation algorithm (MLP/BP) was used. The scour cone volume (Vf) and length (Lf) were modeled as a function of three variables; water depth (HW), mean flow velocity through outlet (uf) and mean grain diameter (D50). For training and testing model, experimental data in two forms of original and non-dimensional are selected. The results of this research indicate that MLP/BP model can predict the scour cone volume and length. Finally, sensitivity analysis with original and nondimensional data set show that mean flow velocity through outlet (uf) and uf / √(g (Gs-1)D50) have a greater influence on scour cone volume and length rather than other parameters.

Ghost length, cone length and complete level of DG modules

In this paper, we introduce a new numerical invariant complete level for a DG module over a local chain DG algebra and give a characterization of it in terms of ghost length. We also study some of its upper bounds. The cone length of a DG module is an invariant closely related with the invariant level. We discover some important results on it.

Comparison of sensory neuron growth cone and filopodial responses to structurally diverse aggrecan variants, in vitro

Following spinal cord injury, a regenerating neurite encounters a glial scar enriched in chondroitin sulfate proteoglycans (CSPGs), which presents a major barrier. There are two points at which a neurite makes contact with glial scar CSPGs: initially, filopodia surrounding the growth cone extend and make contact with CSPGs, then the peripheral domain of the entire growth cone makes CSPG contact. Aggrecan is a CSPG commonly used to model the effect CSPGs have on elongating or regenerating neurites. In this study, we investigated filopodia and growth cone responses to contact with structurally diverse aggrecan variants using the common stripe assay. Using time-lapse imaging with 15-s intervals, we measured growth cone area, growth cone width, growth cone length, filopodia number, total filopodia length, and the length of the longest filopodia following contact with aggrecan. Responses were measured after both filopodia and growth cone contact with five different preparations of aggrecan: two forms of aggrecan derived from bovine articular cartilage (purified and prepared using different techniques), recombinant aggrecan lacking chondroitin sulfate side chains (produced in CHO-745 cells) and two additional recombinant aggrecan preparations with varying lengths of chondroitin sulfate side chains (produced in CHO-K1 and COS-7 cells). Responses in filopodia and growth cone behavior differed between the structurally diverse aggrecan variants. Mutant CHO-745 aggrecan (lacking chondroitin sulfate chains) permitted extensive growth across the PG stripe. Filopodia contact with the CHO-745 aggrecan caused a significant increase in growth cone width and filopodia length (112.7%±4.9 and 150.9%±7.2 respectively, p<0.05), and subsequently upon growth cone contact, growth cone width remained elevated along with a reduction in filopodia number (121.9%±4.2; 72.39%±6.4, p<0.05). COS-7 derived aggrecan inhibited neurite outgrowth following growth cone contact. Filopodia contact produced an increase in growth cone area and width (126.5%±8.1; 150.3%±13.31, p<0.001), and while these parameters returned to baseline upon growth cone contact, a reduction in filopodia number and length was observed (73.94%±5.8, 75.3%±6.2, p<0.05). CHO-K1 derived aggrecan inhibited neurite outgrowth following filopodia contact, and caused an increase in growth cone area and length (157.6%±6.2; 117.0%±2.8, p<0.001). Interestingly, the two bovine articular cartilage aggrecan preparations differed in their effects on neurite outgrowth. The proprietary aggrecan (BA I, Sigma-Aldrich) inhibited neurites at the point of growth cone contact, while our chemically purified aggrecan (BA II) inhibited neurite outgrowth at the point of filopodia contact. BA I caused a reduction in growth cone width following filopodia contact (91.7%±2.5, p<0.05). Upon growth cone contact, there was a further reduction in growth cone width and area (66.4%±2.2; 75.6%±2.9; p<0.05), as well as reductions in filopodia number, total length, and max length (75.9%±5.7, p<0.05; 68.8%±6.0; 69.6%±3.5, p<0.001). Upon filopodia contact, BA II caused a significant increase in growth cone area, and reductions in filopodia number and total filopodia length (115.9%±5.4, p<0.05; 72.5%±2.7; 77.7%±3.2, p<0.001). In addition, filopodia contact with BA I caused a significant reduction in growth cone velocity (38.6nm/s±1.3 before contact, 17.1nm/s±3.6 after contact). These data showed that neuron morphology and behavior are differentially dependent upon aggrecan structure. Furthermore, the behavioral changes associated with the approaching growth cone may be predictive of inhibition or growth.

잣나무 채종원에서 구과 착과수에 따른 구과 및 종자특성

본 연구는 잣나무의 구과 착과량에 따른 구과 및 종자특성의 변화 양상을 구명함으로써 잣나무 채종원의 효율적 관리방안을 도출하기 위해 수행되었다. 이를 위해 2007년 충주 소재 잣나무 채종원에서 조사를 실시하였는데, 전체 조사목 중 96.3%가 착과되었으며 본 당 구과수는 평균 27.4개였다. 본 당 구과 착과수에 따라 8개의 계급으로 나누어 분석을 했는데, 구과 착과수가 많아질수록 구과길이, 구과폭, 구과무게가 감소하는 것으로 나타났다. 또한 구과 착과수가 많아질수록 임성인편수, 종자생산능력, 충실종자율, 종자무게, 종자효율은 감소하고 둘째해 고사배주율은 다소 증가하는 경향을 나타냈다. 이러한 결과를 볼 때 종자결실이 풍년으로 구과가 다량 착과되는 해에는 평년에 비해 종자의 균일성 및 품질이 저하될 가능성이 높다고 판단된다. 특히, 잣나무는 구과와 종자의 크기가 크고 무거울수록 포지와 조림지에서의 생장이 좋다는 보고가 있는 점을 감안할 때, 결실 풍년으로 인해 종자의 평균적인 크기와 무게가 감소되는 경우 향후 조림지에서의 유묘생장도 저조할 가능성이 있다. 따라서, 이러한 문제점을 해결하기 위해 결실이 풍년인 해에는 착과량을 인위적으로 적정수준으로 조절하거나 종자 정선 시 평년 수준의 종자크기 또는 무게를 가진 것들을 선별하여 공급하는 방안 등 다각적인 대처방안을 검토할 필요가 있을 것으로 생각된다. This study was conducted to examine the relationship between cone abundance and cone/seed characteristics to improve seed quality and seed orchard management of Pinus koraiensis. The data was collected from P. koraiensis seed orchards at Chungju in 2007. That year was a rich year of cone harvest and the average number of cone per tree was 2.5 times much than that of normal year. We collected the cones from all trees in the sample plot of the seed orchard and investigated morphological characters such as cone length, cone width and cone weight. According to cone abundance per tree, the samples were divided into eight classes and analysed by cone analysis method. There is a decreasing tendency of number of fertile scale, seed potential, percent of filled seeds, seed weight per cone and seed efficiency, when the cone number per tree is increased. Additionally, the implications of the results to seed orchards management of P. koraiensis were discussed.