• Journal of applied mathematics & informatics
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• v.36 no.1_2
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• pp.81-92
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• 2018

In this article we study two Multiplicative (generalized)- derivations ${\mathcal{G}}$ and ${\mathcal{H}}$ that satisfying certain conditions in semiprime rings and tried to find out some information about the associated maps. Moreover, an example is given to demonstrate that the semiprimeness imposed on the hypothesis of the various results is essential.

• 월간 기계설비
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• s.4
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• pp.84-100
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• 1990

한미통상마찰등에 가려 관심권 밖으로 밀려나 있던 GATT(관세 및 무역에 관한 일반 협정) 우루과이 라운드 협상이 올 연말 협상 타결이 시한으로 다가옴에 따라 자국에게 좀더 이익이 갈 수 있도록 하기 위해 부산한 움직임을 보이고 있다. UR협상은 동구권의 자유시장 경제체제로의 편입과 함께 세계 경제질서의 재편을 가져오는 가장 중요한 변화 요인으로서 대외에 개방적 운용이 불가피한 우리의 경제에 커다란 영향을 미칠 것으로 전망되고 있다. 건설부문도 예외는 아니여서 정부 및 관계자들이 우리쪽으로 유리한 타결을 위해 고심하고 있다.

• Journal of applied mathematics & informatics
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• v.40 no.5_6
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• pp.1021-1034
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• 2022

In this article, authors derived Petrović's type inequalities for a class of functions, namely, called exponentially h-convex functions. Also, the associated results for coordinates has been derived by defining exponentially h-convex functions on coordinates.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.95-104
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• 2011

Distribution types of native conifers (Juniperus chinensis, Pinus parviflora, Tusga sieboldii and Taxus cuspidata var. latifolia) were studied by phytosociological investigation and ZM method in Ulleung Island, South Korea. Two main types were divided maritime vegetation (Juniperus chinensis forest) and mountain vegetation (Taxus cuspidata var. latifolia forest and Pinus parviflora-Tusga sieboldii forest). The former was divided into sea cliff distribution (J-SC) and sea ridge distribution (J-SR) type. The latter was classified 7 distribution types; Taxus cuspidata var. latifolia forest was rock distribution (Ta-R) and mountain slope distribution (Ta-MS) type, and Pinus parviflora-Tusga sieboldii forest was rock distribution (P T-R), upper and ridge distribution (P T-UR, 3 units sub-types:1sub, 2sub, 3sub), and Mountain slope distribution (P T-MS) type. It was considered that J-SC, Ta- R, and P T-R were maintained by topographic climax, but J-SR, Ta-MS, P T-UR and P T-MS were the process of vegetation succession. Distribution types of topographic climax are entrusted to process of vegetation succession. Types in the process of vegetation succession will be needed tending of forest to promote saplings growth and seedlings germination. Especially in order to restore Tsuga sieboldii forest should be afforest and make forest gap because It is mid shade tolerant tree and purity percentage of its seed is 1~2%. It was considered that the composition of group mixture forest constituted Pinus parviflora, Tsuga sieboldii, Taxus cuspidata, Camellia japonica, Machilus thunbergii and Acer okamotoanum, etc. will be able to restore native vegetation, after take the form of forest gap by strong thinning and pruning of Pinus thunbergii forest.

• Journal of Convergence for Information Technology
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• v.10 no.12
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• pp.208-215
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• 2020

The purpose of this study was to access the effects of detoxification of hair by SUKI(silver tools). The subjects of this study participated 26 persons(EG 13 and CG 13), Experimental group was performed SUKI programs combined with scalp and hair for two times per week, during 8 weeks. The results was of comparison of variations in each groups showed that there was a significant difference(6items) in the experimental group(p<.05). But 2items(Pb, Cs) was not showed it. Among the hazardous heavy metals in research, Al, Ba and Hg showed the greatest reduction rate of difference. Thus, the using of the SUKI tool has been shown to affect some heavy metal emissions (p<.05). In conclusion, it is thought that it can be used as basic data for heavy metal discharge of scalp through continuous research in the future.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.9 no.1
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• pp.1-18
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• 1973

For regulating the depth of midwater trawl nets towed at the optimum constant speed, the changes in the shape of warps caused by adding a weight on an arbitrary point of the warp of catenary shape is studied. The shape of a warp may be approximated by a catenary. The resultant inferences under this assumption were experimented. Accordingly feasibilities for the application of the result of this study to the midwater trawl nets were also discussed. A series of experiments for basic midwater trawl gear models in water tank and a couple of experiments of a commercial scale gears at sea which involve the properly designed depth control devices having a variable attitude horizontal wing were carried out. The results are summarized as follows: 1. According to the dimension analysis the depth y of a midwater trawl net is introduced by $$y=kLf(\frac{W_r}{R_r},\;\frac{W_o}{R_o},\;\frac{W_n}{R_n})$$) where k is a constant, L the warp length, f the function, and $W_r,\;W_o$ and $W_n$ the apparent weights of warp, otter board and the net, respectively, 2. When a boat is towing a body of apparent weight $W_n$ and its drag $D_n$ by means of a warp whose length L and apparent weight $W_r$ per unit length, the depth y of the body is given by the following equation, provided that the shape of a warp is a catenary and drag of the warp is neglected in comparison with the drag of the body: $$y=\frac{1}{W_r}\{\sqrt{{D_n^2}+{(W_n+W_rL)^2}}-\sqrt{{D_n^2+W_n}^2\}$$ 3. The changes ${\Delta}y$ of the depth of the midwater trawl net caused by changing the warp length or adding a weight ${\Delta}W_n$_n to the net, are given by the following equations: $${\Delta}y{\approx}\frac{W_n+W_{r}L}{\sqrt{D_n^2+(W_n+W_{r}L)^2}}{\Delta}L$$ $${\Delta}y{\approx}\frac{1}{W_r}\{\frac{W_n+W_rL}{\sqrt{D_n^2+(W_n+W_{r}L)^2}}-{\frac{W_n}{\sqrt{D_n^2+W_n^2}}\}{\Delta}W_n$$ 4. A change ${\Delta}y$ of the depth of the midwater trawl net by adding a weight $W_s$ to an arbitrary point of the warp takes an equation of the form $${\Delta}y=\frac{1}{W_r}\{(T_{ur}'-T_{ur})-T_u'-T_u)\}$$ Where $$T_{ur}^l=\sqrt{T_u^2+(W_s+W_{r}L)^2+2T_u(W_s+W_{r}L)sin{\theta}_u$$ $$T_{ur}=\sqrt{T_u^2+(W_{r}L)^2+2T_uW_{r}L\;sin{\theta}_u$$ $$T_{u}^l=\sqrt{T_u^2+W_s^2+2T_uW_{s}\;sin{\theta}_u$$ and $T_u$ represents the tension at the point on the warp, ${\theta}_u$ the angle between the direction of $T_u$ and horizontal axis, $T_u^2$ the tension at that point when a weights $W_s$ adds to the point where $T_u$ is acted on. 5. If otter boards were constructed lighter and adequate weights were added at their bottom to stabilize them, even they were the same shapes as those of bottom trawls, they were definitely applicable to the midwater trawl gears as the result of the experiments. 6. As the results of water tank tests the relationship between net height of H cm velocity of v m/sec, and that between hydrodynamic resistance of R kg and the velocity of a model net as shown in figure 6 are respectively given by $$H=8+\frac{10}{0.4+v}$$ $$R=3+9v^2$$ 7. It was found that the cross-wing type depth control devices were more stable in operation than that of the H-wing type as the results of the experiments at sea. 8. The hydrodynamic resistance of the net gear in midwater trawling is so large, and regarded as nearly the drag, that sweeping depth of the gear was very stable in spite of types of the depth control devices. 9. An area of the horizontal wing of the H-wing type depth control device was $1.2{\times}2.4m^2$. A midwater trawl net of 2 ton hydrodynamic resistance was connected to the devices and towed with the velocity of 2.3 kts. Under these conditions the depth change of about 20m of the trawl net was obtained by controlling an angle or attack of $30^{\circ}$.

• 월간 기계설비
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• s.52
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• pp.58-66
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• 1994

설비설계업계가 UR 타결로 인한 국제화 개방화 시대에 대비하기 위해 하나로 뭉쳤다. 지난 1월초부터 국내 굴지의 5개 기계설비용역회사들이 모여 설비설계의 전산화 및 기술개발을 공동으로 모색하기 위한 모임 CO-ME(Computer Mechanical Engineering)를 조직, 컴퓨터에 의한 설계의 표준화작업을 서두르고 있다. CO-ME의 회장을 맡고 있는 이홍규 기계설비엔지니어링협의회 회장(무애청우엔지니어링 대표)은 '국내 실정에 맞는 CAD를 개발, 설비업계에 종사하는 모든 업체가 손쉽게 사용할 수 있고 나아가 해외에서도 사용 가능한 프로그램을 개발할 계획' 이라면서 '각 업체의 적극적인 지원으로 빠른 성과를 보이고 있으나 투자액이 2억원을 넘고 있지만 아직 회수를 못하고 있어 안타깝다' 고 말하고 '그러나 지금은 고생이 되더라고 개척해 놓으면 개방화시대를 당당히 맞이할 수 있을 것' 이라고 덧붙였다. 이 회장은 또 설비업계의 5개 단체인 기계설비협의회가 상호 협력하여 공존공생할 수 있는 방안을 모색중이라고 밝혔다. 본지는 이홍규 회장의 CO-ME에 대한 자세한 소개를 게재한다.

• 월간 기계설비
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• s.45
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• pp.36-45
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• 1994

UR협상에 따라 민간건설시장이 `95년에, 공공건설시장이 `97년에 개방되면 기술력이 강한 선진국이 국내시장에 진출함으로써 자본력과 기술력이 약한 국내업체가 도산하거나 이들이 하도급 업체로 전락할 우려가 있다. 그러나 건설업체가 기술개발에 주력하여 국제경쟁력을 갖추게 되면 국내건설시장보다 50배이상 큰 국제시장에 진출하여 건설산업이 70$\~$80년대와 같이 국가경제발전에 크게 기여할 수 있는 계기를 마련할 수도 있다. 기술개발의 주체가 민간기업이므로 향후 건설기술의 정책은 민간기업이 기술개발에 주력할 수 있는 여건을 조성하는데 초점이 맞추어질 것이다. 민간기업의 기술개발 촉진을 위하여는 신기술지정제도 등 기존의 여러 가지 인센티브제도를 보강하는 한편, 현재 가격중심인 입찰$\cdot$계약제도를 기술중심으로 전환하여 기술력이 우수한 업체를 우대할 것이다. 아울러 적산제도와 시방서 등의 제기준을 국제규범화하고 외국업체의 국내 진출시 예상되는 각종 클레임 문제에 대하여도 대응방안을 마련할 것이다.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.49-55
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• 2017

The objective of this research was to investigate the effects of planting date, root pruning and uprooting on growth, yield and budding ratio of 'Seolhyang' strawberry (Fragaria${\times}$ananassa Duch.). Planting dates of plantlets with 60 ~ 70 days old were September 7th, September 14th and September 21th. Root pruning rates were controlled to 25% (RP 25) or 50% (RP 50) before transplanting. In the uprooting treatments, the plantlets were pulled out on root media and were replanted into same bed at 10 days (UR 10) and 20 days (UR 20) after transplanting. The delayed planting dates of plantlet resulted in the suppressed growth of plant, reduced yield, and slight earlier appearance of flower buds. The RP 50 treatment showed the lowest value among root pruning treatments in growth and yield, but appearance of flower buds slightly fall behinds. The UR 20 treatment only made flower budding earlier by 6 days than non-treatment. All of root stress treatment was appeared to decrease vegetative growth and yield except the RP 25 treatment. Above results imply that strong root stress was required to emerge second flower bud earlier but which reduced overall growth and yield in 'Seolhyang' strawberry.

• Land and Housing Review
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• v.2 no.4
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• pp.529-538
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• 2011

Recently, one of the critical issues in Korea is the huge debt and future role of Korea Land and Housing Corporation. In this regards, the purpose of this study is to get implications from other public housing agencies in Asian countries such as UR of Japan, HDB of Singapore and HA of Hongkong. The changes of housing policy since 1960s, business and financial structure of housing agencies in each nation are investigated and compared. As a result, some policy directions can be proposed as follows : review of current mass housing program, relaxing qualifications for public rental housing, promotion of urban renewal projects, reinforcing cooperation with private sector and local governments, more government's support to LH's financing and loss from businesses for public interests and re-evaluation of LH's debt. The contribution of this study is that suggestions to improve housing policy and to alleviate financial problem of LH are based on the actual conditions of public housing agencies in Asian countries where the housing policy implementation system is similar to Korea, not on the theoretical basis.