• Journal of Biosystems Engineering
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• 제29권5호
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• pp.433-440
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• 2004

Worldwide consumption of vegetable soybean has been increasing recently, but in the process of vegetable soybean production, threshing and separation work accounts fur about $80\%$ of overall labor. Therefore, developing of the vegetable soybean thresher is necessary to reduce the cost of labor. The main objective of this study is to acquire the basic in-formations for design of the vegetable soybean thresher which is suitable for domestic circumstances. We made the experimental system to investigate the threshing and separating performance at the several speeds of threshing cylinder and separating blower according to the kinds of threshing tooth. The result are as follows; Threshing performance of vegetable soybean thresher was shown as the best in case the threshing tooth made of rubber which has the 80 of Shore hardness was used at the circumference speed of cylinder of 5.8$\~$8.1m/s. Also separating cleaning performance of vegetable soybean thresher was shown as the best at more than 1,300 rpm of blower speed and $60\~80\%$ of opening ratio of suction port.

• Journal of Biosystems Engineering
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• 제7권1호
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• pp.33-41
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• 1982

When wet-paddy is threshed by conventional auto-fed thresher, the threshed material under the concave is difficult to separate with pneumatic separation only. The development of thresher with an oscillating sieve in addition to the conventional pneumatic separation has been recommanded to improve the separation of grains from straw and chaff having high moisture content. This study was intended to evaluate the separating performance of an oscillating sieve and to obtain the effective operation conditions of the sieve separation. The sieve with oscillating in an elliptical motion was developed and installed in the experimental unit which can simulate the separating operation of the conventional auto-fed thresher. Results of the study are summarized as follows: 1. The flowing velocity of grains on oscillating sieve was increased as the sieve frequency increased but the feed rate did not significantly affect the flowing velocity of grains on sieve. 2. The effects of sieve frequency and the direction of sieve rotation on the separating performance by oscillating sieve show that increasing the frequency of sieve driving crank above the 460 rpm in the same direction of material flow (con-flow) improved the separating performance. 3. The height of grain guide plate and air velocity through the sieve to optimize the separating performance of oscillating sieve were experimentally determined to give about 10cm above the sieve and 7 m/s, respectively.

• 수산해양기술연구
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• 제52권2호
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• pp.88-95
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• 2016

Most grid sorting has been used to sort out flatfish in shrimp fisheries, while double grid systems have been tested to separate smaller shrimp. The escape of juvenile red seabream through separating panels made with steel grids or large mesh tested for masking effects in a two-species system. Fish behavior was observed in a circulating water tank. The escape rate was 20% greater with the separating codends than with the normal codend in the single-species experiments. The rates in the two-species experiments were 30% or 20% greater than the single-species rates for the normal or separating codends, respectively. The seabream retention rates in the grid separator codend decreased as rockfish retention increased, possibly due to a threat effect. Conversely, the retention rate of both species increased concurrently in the net separator, possibly due to a masking effect. The escape rates of juvenile red seabream varied by compartment in the mesh separating codend. These results suggest that grid separating codends can be used in the field as towed fishing gear to reduce juvenile catch.

• 대한치과기공학회지
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• 제30권1호
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• pp.17-23
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• 2008

Gypsum products are used for the preparation of stone casts of oral and maxillofacial structures and as important adjuncts to dental laboratory operations involved in the production of dental prosthesis. Accuracy and dimensional stability over time are properties of concern in fixed prothodontics. Gypsum products used in denstry are a form calcium sulfate hemihydrate and are classified as 1 of 5 types according to International Standard Organization(ISO) 6873. All die materials exhibit some dimensional change during setting, but expansion and contraction during setting and dimensional changes in response to varations in temperature and the water-powder ratio must be minimal. Although numerous investigators have studied the properties of die materials, several products have been introduced recently with manufacturer claims of superior dimensional stalility. The aim of this study was to determine the surface properties using various separating materials of dental gypsum products The results were as follows 1. In the comparison of first and second plaster distances before separation in different separating agent, there was no significant difference except using Trio separating agent. The interface using Trio separating agent forms like to pores. 2. In the comparison of first and second plaster distances after separation in different separating agent, there was significant difference. The interface of plasters using WD-40, Trio and Vaseline was showed some gaps. Each they were measured at average 7.97 $\pm$ 2.07 ${\mu}m$, 63.09 $\pm$ 23.25 ${\mu}m$, 27.59 $\pm$ 4.19 ${\mu}m$. 3. In the comparison of the surface, the surface of control sample(using none seperating agent) showed irregular properties and the surface using Trio and Vaseline become wrinkled. Specially the surface using Vaseline was showed shiny properties. But the surface using MAGIC SEP, Plaster seperating agent, WD-40 showed regular properties.

• Journal of Biosystems Engineering
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• 제42권4호
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• pp.242-250
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• 2017

Purpose: This study was conducted to determine the appropriate operating conditions through a factorial experiment for the secondary separating part of the self-propelled pepper harvester. Methods: An experimental setup that simulates the secondary separating part of the self-propelled pepper harvester was organized. Test samples were classified into three types according to the number of peppers on a stem, and 12 sets were prepared for each type. Among the operating conditions of the secondary separating part, the rotational speed of drum B (four levels), radial clearance between drums and cylindrical teeth (three levels), and speed ratio between the three drums (two levels) were set as the test factors, and tests were repeated three times for different levels of each factor. The appropriate operating conditions were determined by analyzing the separation ratio and damage ratio of the peppers collected through the secondary separating part. Results: The test factors changed the overall separation ratio and overall damage ratio in similar trends. In other words, the conditions that caused high overall separation ratios also exhibited high overall damage ratios. Owing to the high overall damage ratio in the condition with the highest overall separation ratio, the operating conditions should be selected considering both ratios. Conclusions: When the condition with more than 60% of overall separation ratio and less than 15% of overall damage ratio was considered as the appropriate operating condition, 70 rpm of the rotational speed of drum B, 5 mm of the radial clearance between drums and cylindrical teeth, and 7:3:5 for the speed ratio of the three drums A, B, and C should be applied for the secondary separating part used in this study. Supplementary studies will be required in the future to find optimal operating conditions through the actual field test under further divided test factors.

• 한국초등수학교육학회지
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• 제22권2호
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• pp.183-198
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• 2018

본 논문은 모으기와 가르기 활동에서 0의 처리에 대한 시사점을 찾기 위해 모으기와 가르기 활동을 이론적으로 고찰하고 7개국의 교과서와 5차 교육과정부터 2015 개정 교육과정에 따른 우리나라 수학 교과용 도서를 분석하였다. 모으기는 덧셈과 유사한 정의와 성질을 지니지만, 가르기는 정의하기 어려우며 뺄셈과 유사한 성질을 지닌다고 보기 어렵다. 연산의 의미상으로는 모으기와 가르기는 '부분-부분-전체(part-part-whole)' 상황으로 볼 수 있으나 덧셈과 뺄셈 상황의 일부분에 해당한다고 볼 수 있다. 외국 교과서를 분석한 결과, 싱가포르와 말레이시아 교과서에서는 0을 이미 학습한 후 0을 모으기와 가르기 활동에서 포함하나, 그 밖의 국가들은 0을 모으기와 가르기 활동에서 포함하지 않는 것으로 확인되었다. 우리나라 교과서에서는 0을 포함하지 않도록 일관되게 제시해 왔으나, 교사용 지도서에서는 0의 처리 여부에 대해 일관되지 않음을 확인할 수 있었다. 이에 따라, 학생 수준을 고려하여 모으기와 가르기에서 0을 포함하지 않고 도입하고자 할 때에는 이에 적절한 상황 맥락 제시가 필요하며, 교사용 지도서에서도 보다 일관성 있는 제시가 필요함을 제안하였다.

• 호남수학학술지
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• 제28권1호
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• pp.1-22
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• 2006

First, we obtain some results of intuitionistic fuzzy congruences on a regular semigroups contained in ($XH,\;XH^c$). Secondly, we introduce the concept of intuitionistic fuzzy idempotent separating congruences on a semigroup and investigate some of it's properties.

• 대한수학회보
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• 제36권4호
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• pp.737-746
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• 1999

For a locally compact Abelian group G, and a commutative Banach algebra B, let $L^1$(G, B) be the Banach algebra of all Bochner integrable functions. We show that if G is noncompact and B is a semiprime Banach algebras in which every minimal prime ideal is cnotained in a regular maximal ideal, then $L^1$(G, B) contains no nontrivial separating idal. As a consequence we deduce some automatic continuity results for $L^1$(G, B).

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.284-290
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• 1993

In order to improve the adaptability of rice transplanter to seeding with different length when transplanting multicropping rice in south China. The seedling separating planting mechanism is resynthesized in the paper. According to the agronomy requirements of seedling's transplanting, optimum motional path of the tip point of planting needle is obtained. by applying the established kinematic model of the separating planting mechanism, the relevant software is compiled. On the basis of the features of the problem, the constrained optimization method is utilized to solve the problem with 24 restrictions. Thus, the optimum structure parameters are obtained to satisfy the path points accurately.

• 대한기계학회논문집
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• 제19권5호
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• pp.1149-1157
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• 1995

The research for variation of coolant film thickness and separating force has been investigated following the examination for friction profile of work roll and roughness change of strip surface in rolling mill producting actual commercial products. The obtained results are as follows ; (1) Coolant film thickness in cold rolling has been increased relative to the circumferential velocity of work roll, and formation of coolant films has decreased with the smaller diameter of work roll. (2) Separating force is related to the formation of coolant film, and large separating force is needed to the formation of coolant film but it is constant after formation of appropriate film. (3) Wear and roughness alleviation of work roll is larger in bottom-roll than in top-roll on cold surface is larger in the direction of width than in roll direction, and changes of roughness and strip surface hardness rarely occurred after 3 passes.