• Earthquakes and Structures
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• v.21 no.6
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• pp.641-652
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• 2021

Digging well foundation has been widely used in railway bridges due to its good economy and reliability. In other instances, bridges with digging well foundation still have damage risks during earthquakes. In this study, a new type of digging well foundation with prefabricated roots was proposed to reduce earthquake damage of these bridges. Quasi-static tests were conducted to investigate the failure mechanism of the root digging well foundation, and then to analyze seismic behaviors of the new type well foundation. The testing results indicated that these prefabricated roots could effectively limit the rotation and uplift of the digging well foundation and increase the lateral bearing capacity of the digging well foundation. The elastic critical load and ultimate load can be increased by 69% and 36% if prefabricated roots were added in the digging well foundation. The prefabricated roots drived more soil around the foundation to participate in working, the stiffness of the bridge pier with root digging well foundation was improved. Moreover, the root participation could improve the energy dissipation capacity of soil-foundation-pier interaction system. The conclusions obtained in this paper had important guiding significance for the popularization and application of the digging well foundation with prefabricated roots in earthquake-prone zones.

• Agricultural and Biosystems Engineering
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• v.5 no.2
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• pp.40-44
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• 2004

This study was conducted to solve the problem of spinach harvesting done by manpower at the outdoor field during the cold winter season. Prototype spinach harvester was designed to dig, pick-up, and collect in a continuous operation for harvesting outdoor field-planted crawling type spinach. In the field test, two types of blades (Type A : angle of $150^{\circ}$, Type B : straight) were used for measuring the cutting loads of spinach and chain conveyor with lugs was used for picking up the root cut spinach. Prototype's vibrating blade reduced the digging power of the fixed blade by $46\%$. The loss was also very little ($0.7\%$) with a digging depth of 4 cm, an oscillation frequency of 748 rpm, and an oscillation distance of 33 mm. The working performance of the prototype spinach harvester was 38 hour/ha resulting to $96\%$ labor cost reduction compared to the conventional harvesting.

• Journal of Biosystems Engineering
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• v.27 no.4
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• pp.311-316
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• 2002

This study was carried out to investigate the optimum operating conditions of the air injection type onion peeling device which could be attached to a prototype onion peeler. An onion, stem and root was cut and some vertical line was dug in 1 mm depth on the skin, was put on the two parallel rollers. The diameters of the rollers were 105 mm and the ratio of peripheral velocity was 3:2, and moved by a geared motor. Air from the nozzle with high pressure and velocity was jetted to the rotating onion on the revolving rollers, and then the skin of the onion was stripped. On the test, the rolling characteristics of the experimental materials were measured. The effective peeling conditions were, the number of digging line on the skin of the onion was 4, and the air jet pressure was above 392.3 kPa(4.0 kg/$\textrm{cm}^2$) when the peripheral velocity was at 2.4 m/s. On these conditions, time requirement to peel an onion was less than 2 sec.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.155-163
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• 1993

An American ginseng(Panax quillquefolium L) industry has emerged in British Columbia, Canada over the past ten years. Interest has grown very rapidly and with this development, attention is now moving away from field production issues and emphasis is being directed to enhancements in ginseng storage, drying and processing. There is a dearth of knowledge on these aspects even though they are crucial to international competitiveness. Enhancement dicatates the application of a systems approach to optimizing the harvest and post - harvest production system(crop digging, pre - washing cold storage. washing, drying and post - drying storage). Research in British Columbia to date has focussed on drying and storage issues and has resulted in the design of an enhanced commercial drying system. The role of dryer management, loading rates, airflow rates and pre - drying cold storage on American ginseng root drying rates and root quality were examined. From the dryer management experiments, there are distinct advantages to size sorting root to yield optimum drying rates. If unsorted root is used, efficiency is increased if the trays are systematically rotated. Loading rate experiments illustrate that increasing rates above those currently used in commercial dryers are possible without any sacrifice in quality. This has significant implications for commercial drying. Pre - drying cold storage is a most significant tool for managing drying operations. Over a period of six weeks, no discernable decrease in quality was found as a consequence of cold storage. Further, the moisture loss and the associated root surface changes(loss of surface soil in storage for example) provide new challenges for root quality management. Continued research and technological innovation will be crucial in addressing the demanding challenges of the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.4
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• pp.92-104
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• 2002

This study investigates, analyzes, and summarizes Dansplantation techniques and methods through practical methodology centering on fieldwork in order to present effective planting methods for large trees that have important significance. The conclusions are as follows : 1. The transplantation process of a large tree generally consists of the stages of digging up a tree, manufacturing a carrier frame, loading the tee on a vehicle, transporting, transplanting the tree, installing a strut and maintaining and managing the new transplant. In addition, planting a tree on a mounted place includes the primary procedures of trimming out the root, and preparing for transplanting the tree on a mounted place, as well as the secondary work of trimming out the root, transplanting a tree on a mounted place, maintenance and management. 2. In order to decide on a transplantation method for a large-sized tree, a structure calculation has to be performed first. That is, one must calculate the weight of the tree and the allowable stress of the strut (H-beam, etc.) fhst and then decide on the upper method through computer modeling based upon this structural calculation. 3. As a result of the analysis of a transplanted tree using the life soil method, it was confirmed that large quantities of feeder roots had developed around the root within a short time after the transplantation. The life soil method has proven to be very effective for transplantation of large-sized trees. 4. As for the production method of an H-beam strut frame, it was found that the manufacturing process and disassembly process were simple and proper; therefore, the H-beam frame is an appropriate structure to be used in the transplantation of large trees. 5. The concavo-convex method, which consists of filling the life soil in the concavo-convex area around the root, was found to be a method that promotes the growth of feeder roots within a short period of time and saves the supply of water at the same time.

• Korean Journal of Environment and Ecology
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• v.18 no.1
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• pp.7-17
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• 2004

The objective of this study was to find eco-revegetation measures recycling remnant root-stock of native species which comes to be disused. The monitoring plot was established in Nov.2001 at Honam University's affliated farm that is located in Wolya-Myeon, Hampyeong-Gun, Jeollanam-Do. The plots were monitored 2 times each in Oct.2002 and Sep.2003. Sprout and survival rate of the root-stock including the effect of trunk length, antiseptic treatment, planting season and number of planted were surveyed. The results of the study were as follows Ten tree species including Zelkova serrata among twenty tree species showed outstanding sprout and survival rate (over 90 percent). The growth rate was better in the longer trunk length root-stocks (35cm) than shorter ones (10cm). There was a difference in the size of the root ball when digging the root-stocks. It showed better condition when the root ball sizes were 3 times wide and 5 times deep of the root-stocks or 5 times wide and 5 times deep. Antiseptic treatment on the cuts of the trunk of root-stocks makes a difference in the growth rate. The survival rate of the root-stock showed highest value (100％) when it was transplanted in late autumn (November). And the next best survival rate was reached when it was in early or late spring (March and May)

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.571-578
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• 2013

This study generated regression models through a direct harvesting method to estimate carbon storage and uptake by Pinus densiflora and Pinus koraiensis, the major evergreen tree species in urban landscape, and established essential information to quantify carbon reduction by urban trees. Open-grown landscape tree individuals for each species were sampled reflecting various diameter sizes at a given interval. The study measured biomass for each part including the roots of sample trees to compute the total carbon storage per tree. Annual carbon uptake per tree was quantified by analyzing radial growth rates of stem samples at breast height. The study then derived a regression model easily applicable in estimating carbon storage and uptake per tree for the two species by using diameter at breast height (DBH) as an independent variable. All the regression models showed high fitness with $r^2$ values of higher than 0.98. While carbon storage and uptake by young trees tended to be greater for P. densiflora than for P. koraiensis in the same diameter sizes, those by mature trees with DBH sizes of larger than 20 cm showed results to the contrary due to a difference in growth rates. A tree of P. densiflora and P. koraiensis with DBH of 25 cm stored 115.6 kg and 130.0 kg of carbon, respectively, and annually sequestered 9.4 kg and 14.6 kg. The study has broken new grounds to overcome limitations of the past studies which quantified carbon reduction of the study species by substituting, due to a difficulty in direct cutting and root digging of landscape trees, coefficients from forest trees such as biomass expansion factors, ratios of below ground/above ground biomass, and diameter growth rates.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.302-308
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• 2009

For the proper tree management of Taxus cuspidata, distributed in the High 1 Ski Slope construction area in Baekwoonsan, Jeungsun-gun, Kangwon-do, the growing states of 323 trees(including transplanted 57trees) are investigated. Tree height, rootcollar diameter, D.B.H., stem condition, apical shoot, dead branch, needle growth condition, 2-year-old needle loss, root condition, tree form are investigated. Taxus cuspidata are mainly growing at the sites, high elevated mountain ridge or slopes facing north. Growing states of Taxus cuspidata, distributed in Baekwoonsan are relatively better than those of Taxus cuspidata and Abies koreana at other subalpine zone in Korea. Damaged trees are mainly due to root-removal through transplanting, root-damages by raising the ground level and digging. Several methods of Taxus cuspidata conservation were suggested.

• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.397-403
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• 2009

This study was carried out to investigate the present status of subsoil compaction, and subsoil compaction management in orchard as a basic study for developing a self-propelled explosive subsoiler. Subsoil compaction was evaluated using the soil penetration resistance. Soil cone index was measured using the DIK 5520 type cone penetrometer in several fruit farms such as apple, pear, peach and grapes during growing seasons of these fruit in Jecheon, Gamgok, Choongju, Cheonan and Hwasung areas. Most of the subsoil managing machinery were either explosive type or digging type attached to the tractor or power tiller and turning radius of this machine was more than 3-5 m. Many of the farmers wanted to use the subsoiler which can put lime into soil and rupture soil at the same time. For most of the orchard fields, soil penetration resistance in vehicle traffic area was increased quickly and reached about 1.0 MPa in 5 cm soil depth. As the soil depth increased to 15-20 cm, cone penetration resistance reached about 2.0-2.5 MPa which restricted root growth seriously. Thus it was concluded that one of the main reason for increasing the soil compaction in orchard fields is agricultural vehicle traffic. In the vicinity of fruit trees, compaction is not so serious compared to that of the vehicle traffic area, but as the soil depth increased to 20-25 cm, in most of the orchard fields soil penetration resistance reached about 2.0-2.5 MPa which is the root growth-limiting value. Considering the rooting depth of fruit trees which ranged 30-60 cm for apple, pear and peach, and 20-30 cm for grape, it is necessary to loosen the subosoil and improve the subsoil conditions using subsoiler.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.1
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• pp.131-138
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• 2009

This research was carried out to keep a sharp look-out on changes of estimated unit power and material in landscape architectural construction in Korea from 1962 to 2007 and to suggest basic information for its desirable direction in the near future. The research results are as follows. At first, work classification of estimated unit power and material landscape architectural construction was included under the earth work and in 1974 it had the name which was called landscape architectural process with earth works, and in 1984 the estimated unit power and material of landscape architectural construction was separated from the earth work but it was still under name of estimated unit manpower and material of the engineering construction. In 1972 the estimated unit power and material began with a 'planting' and a 'pruning' and still consists of 7 work classification total: 'sodding and herbaceous sowing', 'digging out', 'planting', 'digging round the root', 'keeping and management', 'rubble masonry' and 'planting for protection of rocks split section'. The processes consist of 29 sub-processes in total. The lawn construction was mainly established in the 1960s, the planting construction in the 1970s, the keeping and management in the 1980s, split section protection in the 1990s along with new technology with keeping management in the 2000s. On the basis of these research results, the process to be added in the near future could be related to new material and new technology and the process might be much more subdivided.