Microstructure‑Strengthening Interrelationship of an Ultrasonically Treated Hypereutectic Al–Si (A390) Alloy

Soo‑Bae Kim,Young‑Hee Cho,Jae‑Gil Jung,Woon‑Ha Yoon,Young‑Kook Lee,Jung‑Moo Lee 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

Ultrasonic melt treatment (UST) was applied to an A390 hypereutectic Al–Si alloy in a temperature range of 750–800 °Cand its influence on the solidification structure and the consequent increase in strength was investigated. UST at such a hightemperature, which is about 100 °C above the liquidus temperature, had little effect on the grain refinement but enhanced thehomogeneity of the microstructure with the uniform distribution of constituent phases (e.g. primary Si, α-Al and intermetallics)significantly refined. With the microstructural homogeneity, quantitative analysis confirmed that UST was found tosuppress the formation of Cu-bearing phases, i.e., Q-Al5Cu2Mg8Si6, Al2Cuphases that form in the final stage of solidificationwhile notably increasing the average Cu contents in the matrix from 1.29 to 2.06 wt%. A tensile test exhibits an increasein the yield strength of the as-cast alloy from 185 to 208 MPa, which is mainly associated with the solute increment withinthe matrix. The important role of UST in the microstructure evolution during solidification is discussed and the mechanismcovering the microstructure-strengthening interrelationship of the ultrasonically treated A390 alloy is proposed.

Effect of Ultrasonic Melt Treatment on Solidification Microstructure of Al–5Ti–1B Alloy Containing Numerous Inoculant Particles

Soo‑Bae Kim,Jae‑Gil Jung,Young‑Hee Cho,Su‑Hyeon Kim,Kwangjun Euh,Jung‑Moo Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The effect of ultrasonic melt treatment (UST) on the solidification microstructure of an Al–5Ti–1B alloy containing highvolumefractions of Al3Tiand TiB2particles is investigated for various UST times with different melt holding times. Theas-cast Al–5Ti–1B alloy is composed of TiB2and polygonal Al3Tiparticles (present prior to UST), plate-like Al3Tiparticles,and Al grains (formed during UST and/or solidification). The UST causes a size reduction and homogeneous distributionof the TiB2-agglomerated region containing many submicron-sized TiB2particles pushed to the grain boundaries. The USTslightly decreases the size and improves the distribution of polygonal Al3Tiparticles enriched in the TiB2-agglomeratedregion. Unlike the TiB2and polygonal Al3Tiparticles, which exhibit a minor refining effect, the plate-like Al3Tiparticlesshow a significant refinement with UST application. The UST has a significant effect on the size distribution of Al grains byinducing the formation of medium-sized grains at the expense of small and large grains; however, it only has a slight effecton grain refinement. The degree of microstructure modification increases with increasing UST time but decreases with meltholding time after UST. The mechanisms for the refinement and dispersion of the TiB2and Al3Tiparticles and Al grains arediscussed considering fragmentation, nucleation, and growth behaviors induced by the UST and subsequent solidification.

하악골 절제술후 재이식된 돌결자가골 재이식 : 치험 3례

김 식,김수관,김운규,김수민,류종희,이준길,조경안,김수흥,정태영,여환호 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.2

We described three cases of immediate reimplantation of a frozen-thawed autogenous mandible composed of a mixture of iliac bone, marrow, and particulate hydroxyapatite in tumors of the mandible. Acceptable outcomes were obtained in three patients who underwent immediate autogenous mandibular graft reconstruction. The conditions leading to successful outcome of the procedure are also discussed. Reimplantation of frozen autogenous lesioned mandible was performed in three patients with mandibular tumors. Two reimplanted grafts survived without complications following surgery. One case had postoperative infection that resolved with appropriate antibiotic treatment. There were no recurrences of the primary lesions. Satisfactory facial contour after surgery was achieved. These results are most promising, and we believe that, with further refinement, this technique will offer a new and acceptable modality for facial reconstruction in patients with cancer.

제품보호용 포장재 개발

김정필,강재현,박대연,유성구,서길수 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.1

The environment to which a packaged-product is exposed, during handling and transportation, very often includes temporary storage. In the interest of conserving warehouse cube, packaged-products are stacked upon one another to a height which far exceeds that possible in a railcar, truck-trailer, aircraft or other conveyance. the hight to which the height to which a packaged-product may be stacked will vary depending upon the warehouse ceiling height-seldom over twenty feet. This procedure for expirimental covers testing of packaged-products weighing under 100 pounds when prepared for shipment. The BASIC requirements of this procedure consist of vibration and drop tests-which must be performed in that sequence.

지보공법에 따른 토사터널의 거동에 관한 수치해석

김진태,박병수,정길수,유남재 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.A

Numerical analysis were performed to investigate the stability and internal movement of tunnel located beneath the base of abutment of bridge according to the method of supporting tunnel. Two supporting methods of the multi-staged grouting method with steel pipes and the large diameter of pipe supporting method were used in the centrifuge model tests. The slip form of model lining, specially built to simulate the process of tunnel excavating under the condition of accelerated g-level, was used in the centrifuge model tests. Four centrifuge model tests were performed, changing the supporting methods of the multi-staged grouting method with steel pipes and the large diameter of pipe supporting method and the location of model abutment base of bridge. For internal displacement of tunnel, movements of the crown. The left and the right sides of spring line were measured during the proceeds of excavating tunnel in centrifuge model tests. Test results were compared with numerically estimated values of internal displacement of tunnel by using the commercially available FEM software of PENTAGON-3D. It was found that they were in good agreements and the large diameter of pipe supporting method was more stable than the multi-staged grouting method with steel pipes with respect to the internal movement of tunnel.

폐기물 처리에 있어서 공동생산에 관한 연구 : A Study on Coproduction in the Waste Processing

김길수 全北行政學會 2000 全北行政學報 Vol.14 No.1

최근 들어 생활수준의 향상, 생활양식의 변화에 따라 쓰레기의 발생이 급격히 증가하고 있다. 쓰레기의 급증으로 처리비용의 증가, 처리시성의 부족, 환경악화 등의 문제가 발생하고 있다. 폐기물을 처리하기 위해 많은 정책적 노력을 기울여 왔다. 정부도 단순히 쓰레기를 청소한다는 개념에서 재활용으로 정책을 변경하였고, 정책목표를 폐기물최소화에 두고 있다. 폐기물처리에 대한 가장 근원적인 해결방법은 최종 처분하는 폐기물의 양을 최소화해야만 한다. 이를 위해서는 지방정부의 주민이 상호 협력하는 공동생산 방법으로 쓰레기처리라는 공공서비스를 생산하고 전달하는 방법을 적극적으로 고려해야만 할 것이다. 본 연구는 주민의 자발적인 협력과 정부의 정책적 노력에 의해 쓰레기문제가 해결될 것이라는 전제 하에 쓰레기 감량화와 폐기물 재활용에 영향을 미치는 요인을 분석하였다. 설문조사결과 응답자들은 쓰레기문제가 심각한 것으로 인식하고 있으며, 이것을 해결하기 위해서는 주민들이 쓰레기의 감량화와 재활용을 노력이 필요하다고 인식하고 있다. 또한 주민들이 쓰레기 감량화와 재활용에 필요한 지식은 갖고 있지만 시간과 노력이 소요되어 불편하다는 반응을 보이고 있다.

감꼭지나방 생태적 특성 및 방제약제 선발

김정화,김길하,조수원,박은철,김순섭,황태구,최상기 충북대학교 첨단원예기술개발연구센터 1999 연구보고서 Vol.4 No.-

경남지역과 충북지역 감나무의 재배, 해충 방제실태를 농가 방문하여 설문조사 한 결과 감 재배경력은 경남지역이 평균 10년이며, 충북지역은 평균 5년 정도이다. 감 재배 주수는 대다수 농가가 20주 이상이고, 재배관리에 대하여 자문을 받는 곳은 농업센터나 농약사 및 연구소 등이었다. 김 품종은 경남지역에서는 부유와 서촌조생, 충북지역에서는 등시와 월하 등을 재배하고 있었다. 시비종류는 이른봄 에 퇴비나 복합비료를 주었고, 감나무 생장 중 열매나 저장 중 열매에 발생하는 해충이 발견되었다. 해충방제를 위해 살충제를 살포하고 있는데 주로 감꼭지나방, 진딧물, 잎말이나방 및 깍지벌레 등으로 파마치온, 파단, 코니도, 신파마치온, 수프라사이드 등을 살포하였다. 감꼭지나방(Stathmopoda masinissa)의 발육생태를 조사하기 위하여, 감꼭지나방을 야외에서 채집하여 온도±1℃, 광주기 16L:8D, 상대습도 50~60%에서 실내 사육하였다. 각 층태별 기간은 알 7.4일, 유충기간 34.7일, 용 15.5일이었다. 각 령기간은 1령 3.5일, 2령 4.2일, 3령 5.2일, 4령 6.5일, 5령 15.4일이었으며, 특히 유층의 두폭을 측정하여 평균한 결과는 1령 0.20mm, 2령 0.40mm, 3령 0.65mm, 4령 0.87mm, 5령 1.07mm일 이었다. 성충의 수명은 수컷이 6.2일, 암컷이 10.1일 이었다. 용화율은 68.0% 우화율은 59.9%이었다. A survey in Kyungnam and chungbuk areas revealed that the average number of years for persimmon tree farming is 10 and 5 years, respectively. The number of trees per orchard is at least over 20, and the farmers have been usually advised through an agricultural center, an agrochemical store, or agrochemical research center. The varieties of the persimmons they grow are Buyu and Seocheon in Kyungnam, and Doogsi and Wolha in Chungbuk. The kind of fertilizers they sprayed in early spring is either compost or composite fertilizer. persimmon pests are often found in persimmon fruits while on a tree or in storage. Phamathion, Padan, Konido, Sinpamathion, and/or supuraside is usually used to control persimmon fruit moths, aphides, leafrollers, and scale insects. To understand the developmental ecology of the persimmon fruit moth, Stathmopoda masinissa Meyrick, we collected and reared them under the laboratory condition which is at 25±1℃ of temperature, 16L:8D of photoperiod, and 85% of relative humidity. As a result, the developmental period of egg, larva, and pupa were 7.40, 34.7, and 15.5 days, respectively. The average period of each larval instar was 3.50, 4.17, 5.17, 6.46, and 15.42 days, respectively, and the average head capsule width was 0.20, 0.40, 0.65, 0.87, and 1.07mm, respectively. The average adult longevity was 6.2 days for males and 10.1 days for females. The pupation rate and the emergence rate were 68.0% and 59.9%, respectively.

열응답성 나노복합재료의 합성과 LCST에서의 열적특성

김정필,최현국,서길수 영남대학교 공업기술연구소 1999 工業技術硏究所論文集 Vol.27 No.2

Thermal responsive nanocomposite were synthesized by copolymerization of N-isopropyl acrylamide and methylene bisacrylamide(crosslinking monomer) in an aqueous suspension of MAPTC-montorillonite at room temperature. Hydrogels containing 2.0 ∼5.0wt% of montmorillonite exhibited a lower critical solution temperature(LCST) similar to unmodified PNIPAM hydrogel (approximately 33.7℃). However, hydrogels containing 10wt% montmorillonite did not exhibit a measurable LCST. TGA result shows thermal stability of thermal responsive nanocomposite imoroved a little more than the thermal responsive polymer.

更生保護事業의 活性化 方案

金秀吉 濟州大學校 法과政策硏究所 1996 法과 政策 Vol.- No.2

死刑制度의 存廢에 관한 小考

金秀吉 제주대학교 1992 논문집 Vol.34 No.1

SummaryCapital punishment, which has been carried out since the beginning of human history, is not only a legal matter, but also matters of criminal policy, political science and philosophy.As a legal penalty that deprives the criminals of their lives, capital punishment has been given much weight in the penalty history. Before the recent times, capital punishment was admitted in every nation and the execution generally committed cruelties, that is, capital punishment was considered a major method of penalty.Becaria advocated abolition of capital punishment in his "Dei delili e delle pene" (Crimes and Penalties) in 1764, and since that time the necessity and indispensability of capital punishment has been discussed and criticized with no break.According to these tendencies, it became general to abolish capital punishment or to restrict it to a maximal extent in advanced nations. In Korea, only a little discussion has been held on the abolition of capital punishment, and a theoritical, verified study has not been made on it so far. On the contrary, since the establishment of the Criminal Law of Korea in 1953, many laws have been enacted with the intimidation of capital punishment, and 14.3 persons on the average are put to death per year.Considering the present situation, it is significant to explore ways toward the abolition of capital punishment. This thesis, therfore, aims to suggest a method to improve capital punishment and the substitute penalties for it by studying the history and nature of capital punishment, describing and criticizing the theories on its maintemance and abolition, and considering the necessity and indispensability of its abolition.The method to improve the existing capital punishment and the substitute penalties are as follows : (1) Articles for Capital offences must be reduced extensively and a sentence of death should not be passed on political and thought offenders. (2) Approbation of two thirds of the justices of the Supreme Court or more must be needed to pass a sentence of death in the Supreme Court. (3) Tentative abolition of capital punishement, (4) Introduction of the reprieve system operating in China and of the conditioned retrial. (5) As substitute penalties, strict penal servitude for life accompanying parole must be introduced and operated rationally.The above is a method in a transitional stage toward loosening capital punishment or from gradual to general abolition of capital punishment. Capital punishment, which has been carried out since the beginning of human history, is not only a legal matter, but also matters of criminal policy, political scienlfe and philosophy. As a legal penalty that deprives the criminals of their lives, capital punishment has been given much weight in the penalty history. Before the recent times, capital punishment was admitted in every nation and the execution generally committed cruelties, that is, capital punishment was considered a major method of penalty. Becaria advocated abolition of capital punishment in his "Dei delili e delle pone" (Crimes and Penalties) in 1764, and since that time the necessity and indispensability of capital punishment has been discussed and criticized with no break. According to these tendencies, it became general to abolish capital punishment or to restrict it to a maximal extent in advanced nations. In Korea, only a little discussion has been held on the abolition of capital punishment, and a theoritical, verified study has not been made on it so far. On the contrary, siince the establishment of the Criminal Law of Korea in 1953, many laws have been enacted with the intimidation of capital punishment, and 14.3 persons on the average are put to death per year. Considering the present situation, it is significant to explore ways toward the abolition of capital punishment. This thesis, therfore, aims to suggest a method to improve capital punishment and the substitute penalties for it by studying the history and nature of capital punishment, describing and criticizing the theories on its maintemance and abolition, and considering the necessity aud indispensability of its abolition. The method to improve the existing capital punishment and the substitute penalties are as follows: (1) Articles for Capital offences must be reduced extensively and a sentence of death should not be passed on political and thought offenders. (2) Approbation of two thirds of the justices of the Supreme Court or more must be needed to pass a sentence of death in the Supreme Court. (3) Tentative abolition of capital punishement. (4) Introduction of the reprieve system operating in China and of the conditioned retrial. (5) As substitute penalties, strict penal servitude for life accompanying parole must be introduced and operated rationally. The above is a method in a transitional stage trward loosening capital punishment or from gradual to general abolition of capital punishment.