용탕조건에 따른 상용 차량용 어댑터 하우징의 열적특성에 관한 연구

고동국,명순식,강병용,김민수 한국기계기술학회 2018 한국기계기술학회지 Vol.20 No.6

In this study, the thermal behavior of adaptor housing was analyzed by the numerical method. The boundary conditions used to die casting process were the temperature of molten metal and injection time. As the temperature of the molten metal increased, the tensile strength of the product decreased by the blow hole generated in the molten metal, and the decreasing tendency was gradually decreased. As the injection time ofthe molten metal increased, the heat flux rose, but the degree of the increase was very small. So, the injection time of the molten metal had little effect on the thermal behavior and diffusion of the adapter housing. As a result, the heat of the molten metal was transferred into the housing and the thermal behavior spread widely.

표준축사 모델에서 PEB시스템의 적용 및 구조설계 개선방안

박만우,도병호,송준익,Park, Man-Woo,Do, Byung-Ho,Song, Jun-Ik 한국축산환경학회 2009 축산시설환경학회지 Vol.15 No.1

PEB system is more economical when compared with structures commonly used Hot rolled and welded light H-beam was introduced in the Standard Livestock Housing. This study suggested more economical technology for structural design by the reduction of live load, relief of deflection limit and reduction of importance factor. And, when applying wind Load as a result of examination with Low Rise Building Systems Manual considering open model, we can know that when the wind load is big, enclosed model is more stable than open model. In short, Suggesting more economical model and providing the method to reduce natural disaster, by the application of PEB system and the development of technology for structural design, are considered to strengthen the competitive power of farmhouse.

한국 도시주거공간의 공용공간의 모서리 공간에 관한 연구

김정석(Jung-Suk Kim) 한국조형디자인학회 2006 조형디자인연구 Vol.9 No.1

The Korean apartment houses were started to developed by the government from early 1970's. This was aby-product of a five-year program for economic development because it roues up the drift of population to cites. To build up the house effectively for the shortest time, government and building companies focused on uniform and standardized the apartment houses. Individualities of inhabitants or design of living space have been ignored or neglected in many cases by the name of economic efficiency and development until recently. In this study, the author found the key to solve the matter on making good use of the corners of thr living space which considered to be useless space. By installing the glass or metal sculptures on the corner, it suggested the way how to further a creative space in the apartment houses.

자동차용 포그 램프 하우징 재료의 개발

이현우(Hyunwoo Lee),안병우(Byoungwoo Ahn),홍성민(Sungmin Hong),정창호(Changho Jung),장인성(Insung Chang) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

PC(polycarbonate)/PBT(polybutyleneterephthalate) mixture is usually used for housing-reflector material of automotive fog lamp. This material has high HDT(Head Deflection Temperature) and is capable of being aluminum metalized for high reflectivity. However, PC/PBT mixture is more expensive than PP(polypropylene) which is used for automotive head lamp housing. Although PP is cheaper than PC/PBT mixture, PP is not used for light reflector because of its non-polarity. Polarity of material is essential to be aluminum metalized. In this study, PET based new material for housing-reflector material of fog lamp housing, which has polarity and high HDT, is developed to reduce its cost as well as improve its quality..

루프를 이용한 근거리 RFID 리더 안테나

정용선,자르갈사이칸 나이암바얄,신봉섭,고형석,안병철 한국정보기술학회 2014 한국정보기술학회논문지 Vol. No.

This paper proposes a near-field RFID reader antenna based on a loop. The proposed antenna consists of a loop loaded with inductors and resistors, a top ground plane for adjusting the far-field gain, a balun and a metal housing. The near magnetic field is generated by a loop consisting of a circular wire and two orthogonal linear wires. Four inductors are placed on the loop to reduce the loop size and four resistors are used to obtain an impedance matching and to control the near magnetic field strength. A ground plan is placed around the loop to reduce the far-field gain of the antenna. A special balun structure is employed to reduce the radiation from the feeding coaxial cable. The loop and the feeding coaxial cable are placed in a metal housing to produce the near magnetic field only in the region just above the antenna. The antenna is optimally designed using a commercial software, then fabricated and tested. The fabricated antenna has a reflection coefficient less than -10dB over 903-921MHz, a far-field gain of -14.5dB, an H-field of 0.38A/m at 40mm above the antenna surface and a tag read distance up to 630mm when a power of 25dBm is supplied to the antenna. 본 논문에서는 루프를 이용한 근거리 RFID 리더 안테나를 제안하였다. 제안된 안테나는 인덕터와 저항으로 장하된 루프, 원거리 이득 조정용 상부 접지판, 벌룬 및 금속 하우징 등으로 구성된다. 근거리 자기장은 원형 도선과 2개의 교차 도선으로 구성된 루프에 의해 생성된다. 루프 상에 4개의 인덕터를 배치하여 루프의 크기를 소형화하였으며 4개의 저항을 사용하여 임피던스 정합을 얻고 동시에 근거리 자기장 세기를 조정하였다. 루프 주위에 접지판을 배치하여 안테나의 원거리 이득을 감소시켰다. 동축 급전선에 의한 방사를 억제하기 위해 특수한 벌룬 구조를 적용하였다. 근거리 자기장이 안테나 바로 위 영역에서만 생성되도록 루프와 급전 동축선을 금속 하우징 내에 설치하였다. 상용 소프트웨어를 이용하여 안테나를 최적 설계한 후 이를 제작하여 시험하였다. 제작된 안테나는 903-921MHz에서 -10dB이하 반사계수, -14.5dB의 원거리 이득을 보였으며, 25dBm의 전력 인가 시 안테나 표면으로 40mm 떨어진 위치에서 0.38A/m의 자기장 세기, 630mm의 태그 인식거리를 보였다.

루프를 이용한 근거리 RFID 리더 안테나

정용선(Yong-Sun Jung),자르갈사이칸 나이암바얄(Jargalsaikhan Nyambayar),신봉섭(Bong-Sup Sin),고형석(Hyung-Suk Koh),안병철(Bierng-Chearl Ahn) 한국정보기술학회 2014 한국정보기술학회논문지 Vol.12 No.8

This paper proposes a near-field RFID reader antenna based on a loop. The proposed antenna consists of a loop loaded with inductors and resistors, a top ground plane for adjusting the far-field gain, a balun and a metal housing. The near magnetic field is generated by a loop consisting of a circular wire and two orthogonal linear wires. Four inductors are placed on the loop to reduce the loop size and four resistors are used to obtain an impedance matching and to control the near magnetic field strength. A ground plan is placed around the loop to reduce the far-field gain of the antenna. A special balun structure is employed to reduce the radiation from the feeding coaxial cable. The loop and the feeding coaxial cable are placed in a metal housing to produce the near magnetic field only in the region just above the antenna. The antenna is optimally designed using a commercial software, then fabricated and tested. The fabricated antenna has a reflection coefficient less than -10dB over 903-921MHz, a far-field gain of -14.5dB, an H-field of 0.38A/m at 40mm above the antenna surface and a tag read distance up to 630mm when a power of 25dBm is supplied to the antenna.

고려시대 금속수공업과 匠人

이정신(Lee Jungshin) 한국중세고고학회 2019 한국중세고고학 Vol.- No.5

고려시대 수공업은 관영·민영, 그리고 소수공업으로 나눌 수 있는데 금·은·동 등을 채굴제련하는 소 수공업은 원료를 주로 조달하므로, 제품 생산은 관영과 민영, 그리고 사원의 공장이 담당했다. 금·은·동 등의 금속자재는 대다수가 소민들의 공납으로 이루어졌으며, 이를 국가가 수취하여 주로 관영 공장으로 하여금 만들게 했다. 정부는 필요에 따라 각 관청에 물품제조에 필요한 공장을 전속시켰는데 그 중 금속 수공업은 장야서에 주로 전속되어 있었다. 관속공장은 공역을 부담하는 대가로 국가로부터 녹봉이나 토지를 받았으며 1년 중 300일 이상 근무하였다. 이들이 오늘날까지 남아있는 우수한 고려시대 금속제품 생산의 주역이었다. 그러나 녹봉이나 토지를 받는 계층은 최고 기술자에 한하고 나머지 상당수의 공장들은 국가가 필요할 때 차출하여 부역의 형태로 근무하게 했다. 고려시대는 관영수공업의 운영과 우수한 기술자를 확보하기 위해 공장안(工匠案)을 작성하고 공장역을 세습하게 하였다. 국가는 공장(工匠)에게 입사할 수 없다고 명시하였으나 고려 전기에 공장 출신으로 입사한 사례는 많이 나타난다. 이에 따라 정부의 입장은 공장 자녀 중 1명은 반드시 아버지 직업을 이어받도록 하여 수공업 기술의 연속성을 확보하고자 했다. 민영 수공업자는 유동장(鍮銅匠), 야장(冶匠), 옹장(甕匠), 와장(瓦匠), 목장(木匠) 등이 있었는데 이들은 혼자서가 아니라 몇 사람이 협업하여 분업을 통해 만들었을 것이다. 충렬왕대에는 지방에서도 공급이 수요를 따르지 못하게 되어 중앙에 있던 상당수의 유동장이 지방으로 옮겨갈 정도였다. 고려 말에 가서는 금·은·유기그릇 사용을 금지하는 기록이 많이 보인다. 이는 소의 해체로 인해 금속재료의 공급량이 줄어든 것이 가장 큰 요인이며, 이 이외에 민가에서 금속제품에 대한 수요량이 늘어난 것도 또 하나의 요인이었다. 안양사명 반자(1252)에는 ‘경사공인지가(京師工人之家)’ 기록이 보인다. ‘경사공인지가’는 서울의 수공업 공장을 의미하는 것으로 이미 고려시대에 다량의 물품을 제조하여 판매하면서 한편으로는 주문생산도 가능한 공장이 있었음을 추정하게 한다. 사찰에서는 사원 수공업자와 더불어 필요에 따라 관속공장을 차출하거나 민간 수공업자들에게 대가를 지불하고 만들게 했다. 금속제품의 생산은 개인보다는 집단으로 분업해서 생산하는 것이 효과적이므로 관공장이나 사공장 모두 조직적인 생산자 집단에서 생산했다. 조선전기 기록이기는 하지만 노야장의 경우 물자를 만드는 인원은 10명-30명으로 구성되어 있어 금속종장은 최소한 10명 이상으로 구성되어 있음을 짐작할 수 있다. 그러나 지방 관청이나 민간 수공업자들은 그만한 인력을 확보할 여력이 없어, 심지어는 1명이 감당하기도 했다. 고려후기의 민영과 지방관청 수공업의 부진은 조선시대에 가서도 그대로 이어져, 조선초기 역시 관영 수공업 위주로 운영될 수밖에 없었다. This paper examines the production of gold, silver, and copper, the handicraft metalwork and the craftsmen in Goryeo dynasty. In Goryeo, the handicraft metalwork were manufactured in the state-owned, private, and Buddhist temple handicraft factories. The Somin[the people of So caste] produced gold, silver, and copper and paid tribute to the state. These metals were used mainly in the state-owned factories which were directed by Jangyaseo Administration. The craftsmen worked more than 300 days in a year. The highest level craftsmen received the official stipend or lands for their works while other craftsmen were drafted as compulsory service when necessary. The artist craftsmen created the excellent metalwork of Goryeo which can be seen and admired today. The state of Goryeo made the list of the craftsmen and made them to succeed the work by heredity to secure good craftsmen. The state banned the craftsmen enter the officialdom but some craftsmen became officials in the early Goryeo. To secure the continuity of the handicraft skills, the state maintained that at least one child of the craftsmen should succeed the parent’s occupation. The private craftsmen comprised brassware, smelt, pottery, roof-tiles, and carpenter craftsmen. They seemed to produce goods by cooperation and division of labor. In the period of King Chungyol, the demand for brassware surpassed the supply in the provinces and the brassware craftsmen moved to the provinces. In the late Goryeo period, the state records show the ban of using gold-ware, silver-ware, and brassware due to the lack of the metal resources. The disintegration of So as well as the increasing demand of private sector caused the lack of the metals. There is a record about “Houses of Capitol Craftsmen”(京師工人之家) in Anyansamyeong Banja(1252). It implies that they produced in a mass scale and engaged in customized production. The Buddhist temples produced also metallic goods in addition to common consumer goods such as paper, tiles, inks, and teas. The temples produced metallic crafts goods when necessary. Both in the state-owned factories and private factories, the metallic crafts seemed to be produced by organized craftsmen groups. A state-owned factory seemed to have at least then craftsmen considering there were 10 to 30 craftsmen in the brassware factory in the records of the early Joseon. But, in the early Joseon, the private factories or the factories under local administration could not afford such human resources as in the state-owned factories, In these sector, even one person seemed to manage the factory. The situation in Goryeo should not be much different.

실내 대기질 진단을 위한 금속산화물 기반 폼알데하이드 가스센서 연구 동향

김윤화,김일두,구원태,장지수 한국센서학회 2019 센서학회지 Vol.28 No.6

People currently spend more than 80% of their time indoors; therefore, the management of indoor air quality has become an important issue. The contamination of indoor air can cause sick house syndrome and various environmental diseases such as atopy and nephropathy. Formaldehyde gas, which is the main contaminant of indoor air, is lethal even with microscopic exposure; however, it is commonly used as an adhesive and waterproofing agent for indoor building materials. Therefore, there is a need for a gas sensor capable of detecting trace amounts of formaldehyde gas. In this review, we summarize recent studies on metal oxide-based semiconductor gas sensors for formaldehyde gas detection, methods to improve the gas-sensing properties of metal oxides of various dimensions, and the effects of catalysts for the detection of parts-per-billion level gases. Through this, we discuss the necessary characteristics of the metal oxidebased semiconductors for gas sensors for the development of next-generation sensors.

자동차 부품용 무도장 메탈릭 플라스틱 소재 개발

최민진,조정민,최영호,최민호,이춘수,성한기,이경실,박기훈,황세종,Choi, Min Jin,Cho, Jeong-Min,Choi, Young Ho,Choi, Min Ho,Lee, Choon Soo,Sung, Han Ki,Lee, Kyoung Sil,Park, Ki Hun,Hwang, Se Jong 한국화학공학회 2022 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.60 No.2

In this paper, paint-free metallic plastic material, polypropylene (PP) and acrylonitrile styrene acrylate (ASA) materials were investigated on the applications for bumper skid plate and outside mirror housing parts. In order to maximize metallic effect, type, size and content of aluminum pigment were optimized based on flop index. Hybrid aluminum pigments with different aspect ratios were used to conceal weld lines. By controlling the fluidity of the material, the flow mark problem, generated on the surface of the part, was resolved. We also investigated the surface defects of flow and weld lines by using the developed modeling and simulation.

금속산업 사내하청 노동자 투쟁의 난관과 운동의 분화

유형근 ( Yoo¸ Hyung-geun ) 한국산업노동학회 2020 산업노동연구 Vol.26 No.3

이 연구는 최근 금속산업의 사내하청 노동자의 조직화가 과거와는 다르게 상당한 성과를 거두고 있는 점에 주목하고, 최근의 조직화 시도의 특징이 무엇이며, 왜 그러한 특징들이 나타나는지 설명하고자 한다. 이를 위해 상호 연관된 두 가지의 연구 문제를 제기했다. 첫째, 2000년대 초중반 활성화되었던 금속산업의 사내하청 노동자 투쟁을 다시 분석해서 당시 투쟁의 주요 요구였던 비정규직 철폐와 정규직화가 실현될 수없었던 구조적 원인을 찾고자 했다. 둘째, 최근 조직화에 성공한 사내하청 노조들은 과거의 투쟁들이 직면했던 제약 요인을 어떻게 극복했는지 설명하고, 최근의 사내하청 노조운동의 분화 양상을 비교하고자 했다. 연구 결과는 다음과 같다. 2000년대의 금속산업 사내하청 투쟁은 원청기업의 사용자 책임을 부정하는 제도적 제약 하에서 기존 공장체제의 변화와 재구성을 요구하며 그 질서와 충돌했다. 이로 인해 당시 사내 하청노조의 권력자원 확장은 근본적으로 제약 받았다. 하지만 2010년대 중반 이후 사내하청 노조운동의 상황이 크게 변화했다. 조직화의 규모가 증가했고 조직화가 이루어진 업종이 이전에 비해 다양해졌다. 이러한 최근 변화는 법률적 제약과 공장체제내의 난관이 여전한 가운데 출현한 것으로, 이 논문은 최근의 조직화 시도들이 그제약과 난관에 성공적으로 적응하면서 세 가지 운동 모델로 분화하고 있다고 보았다. This study aims to explain the characteristics of the recent in-house subcontract workers’ organizing efforts in the metal industry, noting that the recent union organizing campaign has achieved considerable results. To this end, two interrelated research topics were raised. First, we wanted to re-analyze the subcontracting workers’ struggle in the metal industry, which was activated in the early and mid-2000s, to find structural reasons for the failure to realize the abolition of irregular workers. Second, this paper tried to explain how recently organized labor unions overcame the structural difficulties, and to compare the characteristics of the recent union movements of subcontract workers. The results of the study are as follows: the struggle of subcontract workers in the 2000s emerged as a movement calling for changes and reconstruction of the existing factory regime. The struggle also clashed with the existing factory regime under institutional constraints denying the de facto employer’s responsibilities. This served as a challenge limiting the expansion of power resources for subcontract workers. However, the situation of the subcontract workers’ movements has changed significantly since the mid-2010s. This new phenomenon has emerged with legal and structural constraints still existing. The paper analyzes that the recent organizing attempts are successful in adapting to the structural constraints, and are differentiated into three peculiar models. Therefore, today's situation can be evaluated as having higher adaptability and viability of subcontract workers’ movements compared to the past.