• Journal of Biosystems Engineering
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• v.8 no.2
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• pp.1-10
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• 1983

The resulting characteristics of vibrations show different patterns for the various oscillating mechanisms. These vibrations causes troublesome operation problems for the operators and sometimes for the machines. Furthermore, in some cases the practical usage of this oscillating mechanism is constrained by its mechanical conditions. In this study, a balanced oscillating tillage tool with triple blades having different acting area was designed. The horizontal and vertical oscillating accelerations and draft power requirement due to the various travel speeds, lift angles, amplitudes and oscillating frequencies were investigated in a laboratory soil bin with a soil having invariable properties. The results obtained are summarized as follows: 1. Overall, the horizontal acceleration decreased as the oscillating frequency and amplitude decreased. But the increase in travel speed caused the decrease horizontal acceleration. The blade with the lift angle of $30^{\circ}$ exhibited the lowest value of horizontal acceleration among the blades tested. 2. For the vertical acceleration, the fluctuating trend of oscillating acceleration was similar to the trend of the horizontal acceleration. 3. The draft power requirement decreased as the amplitude and oscillating frequency increased. But the increase in travel speed caused the increase in draft power requirement. The blade with the lift angle of $10^{\circ}$ showed the lowest value of draft power requirement among the blades tested.

• Journal of Biosystems Engineering
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• v.6 no.1
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• pp.1-14
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• 1981

A laboratory model test was carried out with a newly designed model to figure out the vibration characteristics of the vibratory tillage tool according to the method of forced vibration, i.e., horizontally and vertically forced vibrations. The results are summarized as follows: 1. The reduction ratios of the draft force of the vibratory blade were 14.2-42.6% for the case where the vibration was forced parallel to the travelling direction of the blade, and 15-54.5% for the vertically forced vibration. And it was thought that the method of vertically forced vibration was preferable to the reduction of the draft force. 2. The ratio of the draft force of a vibratory blade to that of a static one could be represented as a function of V/At. It was found to be possible to reduce the draft force by taking a lower value of (V/Af) and this meant that the effictiveness of tillage practice using the vibratory system would be limited. 3. The torque to the main rotating shaft to vibrate the model blade increased frequency and amplitude. This tendency varied according to the physical properties of tested soil. In case of horizontally forced vibration, the torque was 8~34% less than in case of vertically forced vibration. 4. With the increase of frequency, the total power requirement increased linearly, and also the portion of oscillating power requirement in the total power tended to increase. The magnitude of the total power requirement was 1.4-13 times greater than that of a static one for the case of horizontal vibration, and 1.5-15 times greater for the case of vertical vibration. It was thought that the horizontal vibration of the blade was preferable to the vertical vibration in view of the power requirement. 5. A linearity was found between the amplitude of moment oscillogram and magnitude of oscillating acceleration. Only positive values of moment occurred when the blade was forced to vibrate vertically, but negative values occurred in rarity in the case of amplitude A3 when the blade was forced to vibrate horizontally.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1043-1052
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• 1993

Field experiments were conducted to determine the optimum combination of performance parameters of a single-shank, tractor-mounted oscillating subsoiler. Tests were conducted at frequencies of oscillation of 3.7 , 5.67, 7.58, 9.48 and 11.456Hz ; amplitudes of 18, 21, 23.5, 34 and 36.5 mm ; and forward speeds of 1.84, 2.19 and 3.42 kmph at moisture content close to the plastic limit of the soil. It was observed that there was a reduction in average draft but an a increase in average total power requirement for oscillating than non-oscillating subsoiling. The draft and power ratios were significantly affected by the forward speed, frequency and amplitude. Their combined interaction expressed in terms of the velocity ratio parameter( the ratio of peak tool velocity and forward speed) however has the strongest influence. At the same velocity ratio, the draft reduction and power increase were less at higher amplitude of oscillation . As the oscillating frequency is increased toward the soil resonance the draft requirement becomes less. For the field conditions tested. the optimum operation was obtained at an amplitude of 36.5mm, frequency of 9.48Hz and speed of 2.19 kmph with a draft ratio of 0.33 and a power ratio of only 1.24.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.638-647
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• 2018

We have to prepare for the existing threats from North Korea and potential threats in the future. It is important to utilize our resources as effectively as possible to build military power that brings victory in a war. Based on a sustainable required operational capability, weapons systems at the acquisition stage need to maintain a combat-readiness posture and ensure operational sustainability. To achieve this, establishment of procedures that develop elements of depot maintenance at the beginning, which enables economical and effective depot maintenance during that stage, is essential. First, the requirement paper needs to develop the concept of the depot maintenance requirement through the pre-study outlined by this paper. Second, at the system development stage, a Development Plan of Depot Maintenance draft should be proposed. This is the initial paper that can develop the elements of depot maintenance, and it should be verified by a field test. Third, each force's logistics command should write a Depot Maintenance Direction draft and a Mid-term Requirement of Elements of Depot Maintenance draft with the proven Development Plan of Depot Maintenance draft. Also, the verified paper needs to be realized and renewed by the time the Requirement of Elements of Depot Maintenance draft is completed. In conclusion, the procedures explained above will contribute to build an economical and effective military power in a reality faced with a resource shortage and threats from the enemy.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.569-581
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• 1996

A microcomputer -based data acquistion system was designed and developed at Michigan State University , USA to conduct field data studies. The system designed for the research carried out used an Apple IIe microcomputer for collecting data on-board the tractor. An AII3 Analog to Digital (A/D_ convertor was chosen to interface each analog signal to the microcomputer. A commercially available Dj TPM II was employed to display information such as an engine speed, ground speed, percent drive wheel slip , distance travelled and area covered per hour. The frequency output from the radar unit was channeled through a frequency to voltage (F/V) convertor , so that AII3 Analog to Digital (A/D) convertor could read it. The fuel consumption was measured using on EMCO pdp-1 fuel flow meter attached to the engine fuel line. The draft of the tillage and other drag equipment was determined using strain gages attached to the drawbar of the tractor. The system was developed to collect the draft and fuel requirements for various farm equipment different kind of soils.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.19-26
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• 2003

An oscillating digger mechanism was designed, constructed. and tested. The mechanism is consisted of a six-bar linkage, one four-bar linkage was fer the digger blade and the other one fur variable soil-crop separation. Experimental variables were amplitude(3, 6, 9 mm). frequency(11.2, 14.9. 17.0 Hz), and forward speed of tractor(0.91, 1.13, 1.56 km/h). Each combination of these variables was replicated three times to measure the draft and torque for power requirement evaluation. and the broken-up soil height on the soil separation sieve mechanism. Four parameters λ(the ratio of vibration speed to forward velocity), p(the ratio of vibration acceleration to forward velocity), K(the ratio of vibration acceleration to gravitational acceleration), and T(the product of λ and K) were induced from three experimental variables: amplitude, frequency, and tractor speed. And the power requirement and soil separation ability were analyzed by regression. Though λ and K were known to be the representative parameters. T was the most moderate one to explain draft. torque. and soil separation in this study. It was estimated that the T equal to or greater than 2.4 was the minimum recommended value. Figure 18 would be useful fir the selection of amplitude. frequency, or operating tractor speed once any two variables are known.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.871-874
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• 2008

In the beginning of KBC-2005, many structural engineers had have difficulty in designing the flat plate structures. Recently KBC-2005 has been revising. At this point, we need to study the lateral resisting systems which are based on KBC-2008 draft and applicable to the flat plate structure. When the RC structure system of KBC 2008 draft is compared with that of KBC-2005, there are some differences. (1) Structural system and height limitations according to seismic design category (2) Special Requirement such as special RC shear wall (3) New lateral force resisting system such as shear wall-frame interaction system The KBC-2008 will give structural engineers to choose the various lateral force resisting system

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1026-1035
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• 1993

Further evaluation and modification were done on the new concepts plow (frontal plow), a plow which inverts the soil furrow without lateral displacement . First, kinematics of soil cutting section was analyzed and an experiment was conducted to report draft and power requirement. Second, function of main moldboards was examined and modification was made. As a result of the modification , force applied to the moldboard was reduced, but the furrow inversion became less stable.

• Journal of Arbitration Studies
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• v.16 no.3
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• pp.53-89
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• 2006

At its thirty-second session(Vienna, 17 May-4 June 1999), the UNCITRAL decided that the priority items for the Working Group(Arbitration and Conciliation) should include enforceability of interim measures and the requirement of written (on for the arbitration agreement. The Working Group, at its forty-third session(Vienna, 3-7 October 2005), it had undertaken a detailed review of the text of the revised article 17 of UNCTTRAL Model Law on International Commercial Arbitration, and it had resumed discussions on a draft model legislative provision revising article 7, paragraph (2) of UNCITRAL Model Law. The purpose of this paper is to make research on the contents and issues of the draft legislative provisions on interim measures and preliminary orders, and on the form of arbitration agreement which the Working Group discussed and adopted at its forth-fourth session(New York, 23-27 January 2006). The draft legislative provisions on interim measures and preliminary orders are composed of the following provisions : Article 17-power of arbitral tribunal to order interim measures; article 17 bis-conditions for granting interim measures; article 17 ter-applications for preliminary orders and conditions for granting preliminary orders; article 17 quater-specific regime for preliminary orders; article 17 quinquies- modification, suspension, termination; article 17 sexies-provision of security; article 17 septies-disclosure; article 17 octies-costs and damages; article 17 novies recognition and enforcements; article 17 decies-grounds for refusing recognition or enforcement; article 17 undecies-court-ordered interim measures. There are the following issues in the draft legislative provisions on interim measures and preliminary orders : form of issuance of an interim measures in article 17(2); conditions for granting interim measures in article 17 bis; purpose, function and legal regime of preliminary orders in article 17 ter; obligation of arbitral tribunal to give notice, and non-enforceability of preliminary orders in article 17 quater; burden of proof, interplay between article 17 decies and article 34, and decision on the recognition and enforcement of the interim measures in article 17 decies; placement of article 17 undecies; amendment of scope exception of application in article 1(2). The draft legislative provisions on the form of arbitration agreement are composed of the following provisions : article 7(1) definition of arbitration agreement; article 7(2) arbitration agreement in writing; article 7(3) arbitration agreement if its terms(content) are (is) recorded in any form; article 7(4) arbitration agreement by an electronic communication; article 7(5) arbitration agreement in an exchange of statements of claim and defence; article 7(6) reference to any document containing an arbitration clause. There are the following issues in the draft legislative provisions on the form of arbitration agreement : arbitration agreement in writing in article 7(2); terms or contents of arbitration agreement in article 7(3); arbitration agreement by electronic communication in article 7(4); existence of arbitration agreement in article 7(5); reference to any document containing an arbitration clause in article 7(6); the alternative proposal on article 7; amendment to article 35(2).

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.729-748
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• 2022

Development of radish collectors may enhance radish production and promote upland crop mechanization in the Republic of Korea. Theoretical analysis of power is crucial to ensure the optimum design of agricultural machinery. The aim of the present study is to analyze theoretically the power requirement of a tractor-mounted radish collector under development and to propose design guidelines. The important components of the radish collector were belt-type conveyors, three hydraulic motors, and a direct current (DC) winch motor to operate the total radish collecting process. Theoretical equations were used to calculate the hydraulic motor's power, winch motor power, and draft power at loaded and unloaded conditions. A variety of tractors (44 - 74 kW) and different soil characteristics (hard, firm, tilted, and sandy) were considered to investigate the appropriate drawbar power. Variations of the power requirement of the tractor-mounted radish collector were observed due to modifications of the design parameters. The required hydraulic power of the stem cutting conveyor, stem cutting blade, and transfer conveyor of the radish collector were 0.23 and 0.24, 0.18 and 0.19, and 0.19 and 0.22 kW under unloaded and loaded conditions, respectively. The maximum draft power was calculated as 0.89, 1.07, 1.25, and 1.61 kW at a 30° tilted angle for hard, firm, tilted, and sandy soil, respectively. The calculation showed 2.07 kW DC power was required for unfolding or folding the stem-cutting conveyor. A maximum power of 4.78 kW was prescribed for conducting the whole process of the tractor-mounted radish collector. The analysis of power introduced in this study will be helpful to select the appropriate design parameters for the successful development of a tractor-mounted radish collector.