• Title/Summary/Keyword: preferred density

Search Result 245, Processing Time 0.02 seconds

The Preference Analysis for Optimum Density and Understory Vegetation Management in Healing Forests

  • Kang, Jeong Seok;Ju, Jeong Deok;Shin, Chang Seob
    • Journal of People, Plants, and Environment
    • /
    • v.22 no.5
    • /
    • pp.481-488
    • /
    • 2019
  • The purpose of this study is to suggest how to manage healing forests. Field investigation and surveys were conducted to produce results and 313 questionnaires collected from workers in the forestry sector and ordinary people were analyzed. The results were as follows: it is required to preserve flowering plants, scenic trees, and ecological trees in the understory vegetation, and to remove trees that block the forest landscape, leaving about 50 to 60 percent of the understory vegetation. The preferred density order of broadleaf trees was analyzed as follows: Betula platyphylla > Liriodendron tulipifera > Quercus acutissima. The preferred density order of coniferous trees was analyzed as follows: Abies holophylla > Cryptomerias japonica and Chameacyparis obtusa > Larix kaempferi > Pinus densiflora > Pinus koraiensis. The preferred density in healing forests was 81-89% compared to the number of residual trees for quantitative thinning. Specifically, the preferred density were 87% for P. koraiensis, 86% for L. kaempferi, 81% for P. densiflora, 83% for C. japonica, 84% for C. obtusa and 89% for Q. acutissima. In the case of healing forests, it is recommended to periodically conduct a small-scale thinning with different densities according to the species and diameter of trees based on the results of this study.

A Study on the Preference of the Hedge Planting Pattern (생울타리 식재 패턴의 선호도에 관한 연구)

  • 최연철;김진선
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.25 no.3
    • /
    • pp.234-245
    • /
    • 1997
  • This study aims to clarify the preference of the hedge, on focusing the height, density, width of the hedge, which gives limited dwelling space continuity with outer space, promotes the naturality to dwelling environment, and plays an important role as green space in city. For this, it is performed statistical analysis by field survey, by classifying the hedge as planting pattern, and synthesizing the photograph. Therefore, the results of this study are as follows : 1. In the preference of height of the hedge, when only the hedge is composed, 1.5M is preferred, and when the hedge with deciduous tree, with needle-leaf tree, 1.25M is preferred. 2. In the preference of density of the hedge, which are perfect density, in case of the hedge, which are almost density, in case of the needle-leaf tree, are preferred. 3. In the preference of width of the hedge, 0.4M is preferred. 4. In the preferential factors of the hedges, the preference of the hedge is mainly influenced by density. As the result of multiple regression analysis of visual preference as the height, the density, the width, and the regression equation are as follows : Visual Preference = 0.094+0.412(density)+0.370(height)+0.177(width)

  • PDF

Composition and microstructure of Pb-Sn alloy electrodeposits in pulse plating with low peak current density (낮은 최고전류밀도 조건에서 파형전류전해에 의한 Pb-Sn합금 전착층의 조성 및 조작특성)

  • 예길촌;백민석
    • Journal of the Korean institute of surface engineering
    • /
    • v.24 no.2
    • /
    • pp.88-95
    • /
    • 1991
  • The tin-lead alloy was electrodeposited in the low range of peak current density in order to investigate the change of composition and microstructure of them. The Pb content of alloy deposits, which was decreased with increasing average current density, was relatively lower than that of D.C. plated alloy deposit. The preferred orientation of alloy deposit was changed with increasing peak current density and the surface morphology of alloy deposits was closely related to the preferred orientation of them.

  • PDF

Composition, preferred orientation and magnetic properties of Ni-Fe-Co alloy electrodeposits (Ni-Fe-Co 박막도금층의 조성, 우선배향 및 자기적 성질)

  • 예길촌;김선윤;문근호;김용웅
    • Journal of the Korean institute of surface engineering
    • /
    • v.28 no.6
    • /
    • pp.352-360
    • /
    • 1995
  • The effect of electrolysis conditions on the composition, the magnetic properties and the preferred orientation of Ni-Fe-Co alloy deposits was investigated using the sulfate-chloride bath paddle agitated. Cathode current efficiency increases with the current density, showing the different tendency of the variation from that of the Ni-Fe electrodeposits. The Co content of the deposits decreases with increasing current density, while the content of Ni and Fe is shown to be minimum or maximum at 3A/$dm^2$ respectively. The Ni/Fe ratio of the alloy deposits is lower than that of Ni-Fe deposits. The coercive force($H_c$) of the deposits increases with the Co content in deposit, showing the relatively low value in the range of 1.8~5.0Wt.% Co. The anisotropy field ($H_k$) of the deposits is higher than that of Ni-Fe alloy deposits, The preferred orientation of the deposits is generally (200), but the orientation factor(R) changes with both the increase of current density and the magnetic field applied during deposition.

  • PDF

Preferred Orientation and Microstructure of Zinc Electrodeposit in acid Chloride Solution (우선배향과 두절경조직)

  • 예길촌;박계생;손경옥
    • Journal of the Korean institute of surface engineering
    • /
    • v.16 no.4
    • /
    • pp.173-187
    • /
    • 1983
  • Zinc was electrodeposited at temperature from 20$^{\circ}C$ to 60$^{\circ}C$ over the ranges of the current density from 2 to 20 A/dm2 in acid chloride bath. The cathode overpotentials increased with increasing current density and decreasing tem-perature. The (10$.$3)-(10$.$2) preferred orientation developed at cathode overpotentials below about 450mV, the (10$.$3)(10$.$2)-(10$.$1) texture developed at overpotentials between 500mV and 950mV, and the (00$.$1) (10$.$3) texture developed at cathode overpotentials about 1000mV. The (00$.$1) (10$.$3) preferred orientation was also formed at the lower potentials between 400mV and 850mV at temperatures above 40$^{\circ}C$. The preferred orientations of the zinc deposits was discussed was discussed with both cathode overpo-tential and surface energy of deposit lattice planes. The pyramid type of structure with macrostep developed at low cathode overpotentials and the truncated pyramidal type developed at higher overpotenial.

  • PDF

An Investigation of Preferred Orientation and Microhardness of Nickel-Tin and Tin-Zinc Alloy Electrodeposits on Mild Steel (연강에서의 닉켈-주석과 주석-아연합금 전착층의 우성배향와 미소경도에 관한 연구)

  • Ahn, Deog-Su;Pyun, Su-Il
    • Journal of the Korean institute of surface engineering
    • /
    • v.13 no.3
    • /
    • pp.146-154
    • /
    • 1980
  • The effects of various electrodeposition conditions (deposition temperature and cathode current density) on preferred orientation and microhardness of electrodeposited Ni-Sn and Sn-Zn alloys were studied. At deposition temperatures from 25$^{\circ}$ to 95$^{\circ}C$ and constant cathode current density of 270 and 530 A/$m^2$ Ni-Sn and Sn-Zn were codeposited in chloride-fluoride acid and stannate-cyanide alkaline electrolyte bath respectively. Ni-Sn alloy deposited at temperatures from 25$^{\circ}$ to 35$^{\circ}C$ was composed of single phase of $Ni_3Sn_4$ with 73 wt.% Sn and the one deposited at temperatures from 45$^{\circ}$ to 95$^{\circ}C$ was made of multiphase mixture of NiSn, $Ni_3Sn_2$ and $Ni_3Sn_4$ with nearly equiatomic composition (65.5 wt.% Sn). The random orientation of thermody-namically metastable NiSn phase (hexagonal structure) predominated at deposition temperature range 25$^{\circ}$-45$^{\circ}C$, and the strong (110) preferred orientation was found at 65$^{\circ}$-85$^{\circ}C$ and then disappeared again at 95$^{\circ}C$. The microhardness of Ni-Sn deposits increased with deposition temperature up to 85$^{\circ}C$, and then decreased at constant cathode current density. The preferred orientation and the maximum microhardness were discussed in terms of lattice contractile stress which result from desorption of hydrogen atom absorbed in deposit lattice. The Sn content of Sn-Zn alloy deposits increased with deposition temperature up to 75$^{\circ}C$, and then decreased at constant cathode current density of 530 A/$m^2$. It also decreased with cathode current density up to 530 A/$m^2$, and then increased at constant deposition temperature of 25$^{\circ}C$. Sn-Zn alloy deposits were composed of two-phase mixture of ${beta}$-Sn and Zn. The preferred orientations of ${beta}$-Sn (tetragonal structure) changed with deposition temperature. The microhardness of Sn-Zn deposits decreased with deposition temperature. It also increased with cathode density up to 530 A/$m^2$, and then decreased at constant deposition temperature of 25$^{\circ}C$. The microhardness of Sn-Zn deposits was observed to be determinded more by the Sn content than by the preferred orientation.

  • PDF

The effect of pulse parameters on the composition and the structure of Palladium-Nickel alloy electrodeposits (팔라디움-니켈 합금전착층의 조성 및 조직에 미치는 파형전류인자의 영향)

  • 예길촌;오유청
    • Journal of the Korean institute of surface engineering
    • /
    • v.27 no.5
    • /
    • pp.285-291
    • /
    • 1994
  • The effects of pulse current parameters on the composition and the microstructure of Pd-Ni alloy electrodeposits were studied. The cathode current efficiency of p.c. electrolysis conditions decreased with increasing both mean and peak current density and was lower than those under D.C. electrolysis condition. Palladium content of Pd-Ni alloy increased with increasing both peak current density and on-time, while it decreased with increasing mean current density and duty cycle. The preferred orientation of Pd-Ni alloys changed with increasing mean current density in the sequence of (111)+(110).(100) or (110)longrightarrow(111)longrightarrow(100) or random distribution of crystal structure. The surface morphology of Pd-Ni alloy changed mainly according to the mean current density and was related to the preferred orientation.

  • PDF

The effect of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy electrodeposits (Ni-Fe합금도금층의 조선 및 우선배향에 미치는 전해조건의 영향)

  • 예길촌;김용웅;김용희;김용주
    • Journal of the Korean institute of surface engineering
    • /
    • v.27 no.6
    • /
    • pp.319-326
    • /
    • 1994
  • The effects of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy were studied using the sulfate-chloride baths paddle agitated. Cathode current efficiency is higher in the deposits from bath 2 than that of deposits from bath 1. The Fe content of alloy deposits from bath 2 is nearly constant(19∼21wt.%) in the wide range of current density, while it decreases noticeably with current density in the deposits from bath 1. The variation of Fe content at the edge of specimen is lower in deposits from bath 2 than those from bath 1. The alloy deposits show (111) & (200) preferred orientation for the deposits from bath 1 and bath 2 respectively.

  • PDF

Microstructure of brass electrodeposits in cyanide solution (시안화 황동도금욕을 사용한 黃銅電着層의 현미경조직)

  • Ye, Gil-Chon;Kim, Jong-Kwan
    • Journal of the Korean institute of surface engineering
    • /
    • v.17 no.4
    • /
    • pp.106-119
    • /
    • 1984
  • Brass was electrodeposited over the range of the current densities from 2 to 8 A/$dm^2$ in cyanide bath at 20 and 40$^{\circ}C$. The cathode overpotential increased and the cathode efficiency was decreased respectively with decreasing temperature, increasing current density and addition of organic substance. The perferred orientation of the deposits were associated with the cathode overpotential and the nucleation energy of lattice planes. The (111) preferred orientation developed at the low current density and low cathode overpotential (440-520mV). On the other hand, the (111)+(100) preferred orientation developed at higher cathode overpotential (528-680mV). The (111)+(100) preferred orientation developed over the whole range of overpotential in the cyanide solution with organic additive. The copper content of deposit decreased with increasing current density and decreasing temperature. The morphology of the deposits with no additive was the polygonal body type of structure and the structure of the cross section was columnar structure. The morphology of the deposits with additive, on the other hand, was fine crystallite type of structure. And the structure of the cross section of them was the finer granular structure.

  • PDF

The effect electrolysis conditiong on the composition and the preferred orientation of Co-Fe-Cr alloy electrodeposits (Co-Fe-Cr 합금도금층의 조성 및 우선방위에 미치는 전해조건의 영향)

  • 예길촌;문근호
    • Journal of the Korean institute of surface engineering
    • /
    • v.31 no.6
    • /
    • pp.393-399
    • /
    • 1998
  • The composition and the properred orientation of Co-Fe-Cr alloy electrodeposits were invesigated according to the electrolysis conditions using sulface bath. The current efficiency and the cathode overpotential decrased noticeably with the increase of Cr content in the bath. As the D.C. current density increased increased, the Cr content in the alloy increasd, while Co content decreased and Fe content remained constant, In the pulse current electrolysis, the Cr content of the alloy increased with the mean current density and off-time and then its content increased mord more noticeably with the peak current density than that of D.C. electrolysis. The preferred orientation of the alloy changed from (220)+(111) to (220) with decreasing cathode overpotential.

  • PDF