• Title/Summary/Keyword: Number of passes

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A Study on the Discriminating Factor of 'Hyeon' and 'Ryeong' by the Names of Mountain Passes (고개의 호칭으로서 '현'과 '령'의 변별요인에 관한 연구)

  • Cho, Seung-Rae;Kang, Young-Jo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.35 no.1 s.120
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    • pp.69-78
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    • 2007
  • The purpose of this study is to determine the basis for the names of mountain passes that have been different since antiquity, especially names such as those written in Chinese characters. For this purpose, this researcher focused on 108 mountain passes listed in the section of Gyeongsangdo that is a part of Joseon's representative human geographic literature, 'Sinjong Dongguk Yeoji Seungram'. Then the author found out their location by reviewing 'Joseon Hugi Jibang Jido', 'Daedong Yeojido' and 'Hanguk Jimyeong Chongram'. Out of the 180 passes, 30 were finally selected to be analyzed. Again 15 among 30 were found named as 'Hyeon', 7 as 'Ryeong' and remainder were called either term on occasion. The study tried to find out standards according to whether the 30 passes were named as 'Hyeon' or 'Ryeong'. To carry out the study, the author made 3 hypotheses. First, the passes' altitudes were examined. Then visual characteristics were investigated when seen from the summit of the passes. Finally, the number of the passes' turns was investigated to know whether this discriminates between 'Hyeon' and 'Ryeong'. The results of the study can be summarized as follows. With the altitudes and the visual characteristics as mentioned above, it was not possible to determine features that clearly discriminate 'Hyeon' from 'Ryeong'. However, the number of the turns was significantly different in accordance with the names of the passes, 'Hyeon', 'Ryeong' and 'Hyeon or Ryeong'. It seems that 'Hyeon' and 'Ryeong' were discriminatively used depending on how mountain passes were apparently perceived with the number of their turns.

A Study on Soil Stress and Contact Pressure of Tire (타이어 접지압과 토양속 응력분포에 관한 연구)

  • 박원엽;이규승
    • Journal of Biosystems Engineering
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    • v.26 no.3
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    • pp.245-252
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    • 2001
  • This study was carried out to investigate the effect of three factors(dynamic load, inflation pressure and multiple passes of the tire) on the contact pressure and the soil stresses under the tire. A series of soil bin experiment was conducted with a 6.00R14 radial-ply tire for sandy loam soil. Tire contact pressure at soil surface and soil stresses at 10cm and 20cm soil depth were measured for the three levels of dynamic load(1.17kN, 2.35kN and 3.53kN), for the three levels of tire inflation pressure(103.42kPa, 206.84kPa and 413.69kPa), and for five different number of passes(1, 2, 3, 4 and 5 pass). The following results were drawn from this study 1) As dynamic load, inflation pressure and number of passes of the tire increased, tire contact pressure at soil surface and soil stresses at 10cm and 20cm soil depth increased accordingly. Thus increased in dynamic load, inflation pressure and number of passes of the tire would increase soil compaction. 2) The effect of three different factors, or dynamic load, inflation pressure and number of passes of the tire, decreased as the soil depth increase. Consequently, it was found that the soil compaction at a shallow depth in soil is larger than that at deep place in soil. 3) The increase of dynamic load and number of passes increased soil stress exponentially, but the increase of inflation pressure increased soil stress linearly. The effect of tire inflation pressure on soil stress was relatively less than that of the dynamic load. Therefore, it was concluded that dynamic load is more important factor affecting soil compaction in comparison to the inflation pressure of tire.

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Flow Distribution Characteristics in a Multi-Pass Heat Exchanger (다패스 열교환기에서의 유량분배 특성)

  • Kim, Min-Soo;Kang, Soo-Jin;Lee, Kwan-Soo
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.737-742
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    • 2006
  • This paper numerically investigates to evaluate the performance according to the number of passes and the inlet/outlet diameter in a multi-pass multi-branch heat exchanger. A JF factor is used as an evaluation characteristic value to consider the heat transfer rate and the pressure drop simultaneously. It estimates the performance according to the number of passes and the inlet diameter of the reference heat exchanger. When the ratio of the inlet diameter to the header height is about 0.5, the optimum number of passes is selected along with the inlet diameter.

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The Effect of Dynamic Load, Inflation Pressure and Number of Passes of Tire on Soil Compaction under the Tire (타이어의 동하중, 공기압 및 통과횟수가 토양다짐에 미치는 영향)

  • 박원엽;이규승
    • Journal of Biosystems Engineering
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    • v.27 no.1
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    • pp.1-10
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    • 2002
  • This study was carried out to investigate experimentally the effect of three factors(dynamic load, inflation pressure and number of passes of tire) on soil compaction under the tire. The experiment were conducted with a 6.00R14 radial-ply tire for sandy loam soil using soil bin system. To evaluate the effect of three factors on soil compaction under the tire, the sinkage. density and volume of soil under the tire were measured fur the three levels of dynamic load(1.17kN, 2.35kN and 3.53kN), for the three levels of tire inflation pressure(103.42kPa, 206.84kPa and 413.67kPa), and for three different number of passes(1, 3 and 5). The results of this study can be summarized as follows : 1. As dynamic load, inflation pressure and number of passes of the tire increased, soil sinkage and density increased. and volume of soil decreased. Thus increase in dynamic load, inflation pressure and number of passes of the tire would increase soil compaction. 2. The effect of tire inflation pressure on sinkage. density and volume of soil under the tire was relatively less than that of the dynamic load. Therefore, it was concluded that dynamic load was more important factor affecting soil compaction in comparison to the inflation pressure of tire. 3. The effect of three different factors on sinkage, density and volume of soil decreased as the soil depth increase. Consequently, it was fecund that soil compaction at a shallow depth in soil was larger than that at deep place in soil.

An Effect of Number of Passes in Wire-Cut Electric Discharge Machining on Fine Blanking Dies and Products (와이어 컷 방전가공에서 방전가공횟수가 파인 블랭킹 금형과 제품에 미치는 영향)

  • 유헌일;김세환;최계광
    • Transactions of Materials Processing
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    • v.6 no.3
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    • pp.192-202
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    • 1997
  • This study presents an effect of number of passes in wire-cut electric discharge machining on fine blanking dies and products. Three part fine blanking dies were produced by the difference of numbers of passes discharge machining. Brake pad was produced, through the die produced like that, the objective of this study is the improvement in surface roughness of die block and punch, life extension of die block, the decrease of second fracture dimensions, the rise of productive.

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The Effect of Tire Inflation Pressure on Soil Compaction and Tractive Performance of Tractor (타이어공기압에 따른 트랙터의 견인성능과 토양다짐)

  • 박원엽;이규승
    • Journal of Biosystems Engineering
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    • v.27 no.6
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    • pp.491-500
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    • 2002
  • This study was carried out to investigate experimentally the effect of the tire inflation pressure of a tractor on soil compaction and tractive performance. Two kinds of field experiments were conducted using an agricultural tractor. One experiment is concerned with the tractive performance of the tractor at the three levels of tire inflation pressure; 50kpa, 100kpa and 200kpa, and the other one is about the soil compaction at the four levels of tire inflation pressure; 50kpa, 100kpa, 150kpa and 200kpa, at three different numbers of passes; 1, 3 and 5 passes. From the results of the field experiment, it was found that decreasing the tire inflation pressure decreased the motion resistance of tractor and increased the tractive force and tractive efficiency. The tractive and working performance of the tractor could be improved by the reduction of tire inflation pressure. Increasing the inflation pressure and the number of passes increased the soil compaction. Rate of compaction increased rapidly at the first pass and declined at subsequent passes. To reduce the effect of soil compaction for the whole field, it is recommended that tractor should follow the rut of the first pass from the subsequent passes, and decrease the inflation pressure of the driving tires up to allowable minimum level.

Effect of the Number of Passes through Grinder on the Pore Characteristics of Nanofibrillated Cellulose Mat (그라인딩 처리 횟수에 따른 나노피브릴화 셀룰로오스 매트의 공극 특성)

  • Sim, Kyujeong;Ryu, Jaeho;Youn, Hye Jung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.1
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    • pp.35-41
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    • 2013
  • In this study, we investigated the effect of the number of passes through agrinder on the pore characteristics of nanofibrillated cellulose (NFC) mat. The beaten pulp suspension was used to make NFC suspension using a grinder. To evaluate the pore characteristics of a NFC mat, the surface morphology of the dried NFC mat was observed with FE-SEM and the specific surface area was analyzed with BET nitrogen gas adsorption. The structure of NFC mat was changed with the different number of passes and drying methods. The specific surface area of NFC mat increased with the increase in the number of passes. The 20-passed NFC mat had 20 times larger specific surface area ($141m^2/g$) compared to the 0-passed NFC mat. The specific surface area was strongly correlated with the average pore size in NFC mat. The average pore diameter in NFC mat was calculated from the gas sorption isotherms using BJH model. The value was 13 - 15 nm, indicating that the NFC mat had mesoporous structure.

On the Security of reduced versions of 3-pass HAVAL (3-pass HAVAL의 축소 라운드 안전성에 관한 연구)

  • 박상우;성수학;지성택;윤이중;임종인
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.12 no.4
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    • pp.55-66
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    • 2002
  • HAVAL is a dedicated hash function of the MD family which was proposed by Zheng et al.. HAVAL compresses a message of arbitrary length into a hash value of 128, 160, 192, 224, or 256 bits. HAVAL has a parameter that controls the number of passes a message block of 1024 bits is processed. A message block can be processed in 3,4, or 5 passes. When a message block is processed in three passes, we call such a case 3-pass HAVAL. So, there are three kinds of HAVAL: 3-pass HAVAL, 4-pass HAVAL, and 5-pass HAVAL. In this paper, we study the security of reduced versions of 3-pass HAVAL. We propose a method for finding the collisions for the first two passes of 3-pass HAVAL and for the last two passes of 3-pass HAVAL. This approach of reducing the number of passes is similar to the initial attacks on MD4. We represent the first two passes of 3-pass HAVAL as HAVAL-12 and the last two passes of 3-pass HAVAL as HAVAL-23.

Characteristics of Fatigue Failure according to Thickness of Material and Number of Passes in Cruciform Fillet Weld Zone (십자형 필릿 용접부에서 재료 두께 및 용접 층수에 따른 피로파괴 특성)

  • Lee, Yong-Bok
    • Journal of Welding and Joining
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    • v.28 no.6
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    • pp.45-50
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    • 2010
  • Most of joining processes for machine and steel structure are performed by butt and fillet welding. The mechanical properties and fatigue strength of their welding zone can be effected largely by the differential of generated heat and changes of grain size according to thickness of material and number of passes in welding process. In this study, it was investigated about characteristics of fatigue failure according to thickness of material and number of passes in cruciform fillet weld zone as the basic study for safe and economic design of welding structures. Fracture modes in cruciform fillet weld zone are classified into toe failure and root failure according to non-penetrated depth. It can be accomplished economic design of welding structures considering fatigue strength when the penetrated depth in fillet weld zone is controled properly.

Changes in Microstructures of AA3103 sheets deformed by ECAR (ECAR 가공한 AA3103 판재의 미세조직 변화)

  • Lee J. P.;Huh M. Y.;Chung Y. H.;Park J. W.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.05a
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    • pp.228-230
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    • 2004
  • Samples of the aluminum alloy 3103 sheets were repeatedly deformed by ECAR up to twelve passes. Shear textures developed after the first passage of ECAR. However, the intensity of shear texture components decreased with increasing number of ECAR passages. Observations by TEM and EBSD revealed that the degree of misorientations within the deformed grains increased with increasing number of ECAR passes. Changes in textures and microstructures were hardly observed during recrystallization anneal. Upon subsequent annealing, the samples deformed by a large number of ECAR passes displayed a continuous grain growth. A higher deformation by ECAR resulted in a slower softening, which reflects the stability of ultra-fine grains against the grain growth.

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