• Korean Journal of Materials Research
• /
• v.11 no.7
• /
• pp.569-574
• /
• 2001

The crystal structure, surface morphology and preferred orientation of the copper electrodeposit were investigated by the using sulfate bath with $SiO_2$suspensions and the cathode substrate Au sputtered. As by the addition of colloidal silica in copper electrolytic bath and Au pre-coating on substrate, the crystal particles of deposits was fined-down, made uniform and the account of particles were increased. Hardness of copper electrodeposits with colloidal silica increased about 15% in comparison with that of pure copper deposit film and (111), (200) and (311) plane of X-ray diffraction patterns were almost swept away, so preferred orientation of the copper deposits changed from (111) to (110) plane by codeposit $SiO_2$ and precoating the substrate.

• Journal of Korea Multimedia Society
• /
• v.4 no.3
• /
• pp.257-269
• /
• 2001

Because of increasing number of integrated circuit, there is many tries of making chip of neural network and some chip is exit. but this is not prefer because YLSI technology can't support so large hardware. So imitation of whole system of neural network is more prefer. There is common procedure in signal processing as in the neural network and pattern recognition. That is multiplication of large amount of signal and reading LUT. This is identical with some operation of MLP, and need iterative and large amount of calculation, so if we make this part with hardware, overall system's velocity will be improved. So in this paper, we design neutral network, not neuron which can be used to many other fields. We realize this part by following separated bits addition method, and it can be appled in the real time parallel process processing.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.5
• /
• pp.874-879
• /
• 2016

A wideband stacked patch antenna with parasitic elements, rectangular and triangle shaped patches, is proposed. Two different shaped parasitic elements are placed in the above of main rectangular microstrip patch antenna in order to achieve wide bandwidth for 860 MHz band. Coupling between the main patch and parasitic patches is realized by thick air gap. The gap and locations of parasitic patches are found to be the main factor of the wideband impedance matching. The proposed antenna is designed and fabricated on a ground plane with small size of $119mm{\times}109mm$ for application of compact transceivers. The fabricated antenna on an FR4 substrate shows that the minimum measured return loss is below -11.68dB at 824 MHz and an impedance band of 818~919 MHz(11.7%) at 10dB return loss level. The measured radiation patterns are similar to those of a conventional patch antenna with maximum gain of 2.11 dBi at 824 MHz.

• The Journal of the Korea Contents Association
• /
• v.14 no.11
• /
• pp.628-643
• /
• 2014

The idea to conduct this study stemmed from the following question: What is the appropriate interpretation of the recent change in the user behavior of radio listeners? For some terrestrial radio programs, traditional listeners who mainly listen to them real-time through terrestrial radio broadcasting has been outnumbered by those who access them on smartphones and other mobile devices in a nonlinear way outside the pre-scheduled time slots of the programs. In the research, how terrestrial radio listeners use the new service called podcasting to access and consume audio content were examined by using Q methodology. As a result, three different types of user behavior and perception were modeled. This shows a prominent change in radio content use, which is moving away from the conventional user behavior pattern of radio content, one of the key media for mass communication in the 20th century. Such a development opens up new opportunities to create the same or even a greater user base compared to the existing one for terrestrial radio programs with the users' newly gained mobile access and to replace current radio content by using podcasting as a new service.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.27 no.5
• /
• pp.256-262
• /
• 2017

Digital ink-jet printing technology using ceramic ink, which is thermally stable at high temperature above $1000^{\circ}C$, has an advantage of eco-friendly process applicable to manufacturing products with an excellent durability and various designs. Recently, replacement from conventional manufacturing process to digital process using ink-jet printing technique has been significantly accelerated in ceramic tile industry. In this study, we investigated ink-jet printability of ceramic ink on ceramic tile. Cyan, magenta, yellow, black ceramic inks, which are digital primary color of ink-jet printing, were printed on glazed surface of ceramic tiles, and their printabilities were comparatively analyzed. High temperature sintering process is generally required for manufacturing ceramic products, thus effect of sintering process on printed pattern of ceramic ink was also investigated by analyzing ink penetration depth and ink dot area.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.38 no.3
• /
• pp.1-12
• /
• 2001

In this paper, we investigate and analyze weight distribution of feed forward two-layer neural networks with a hidden layer in order to understand and improve time-consuming training process of neural networks. Generally, when a new problem is presented, neural networks have to be trained again without any benefit from the previous training process. In order to address this problem, training process is viewed as finding a solution point in the weight space and the distribution of solution points is analyzed. Then we propose to initialize neural networks using the information of the distribution of the solution points. Experimental results show that the proposed initialization using the weight distribution provides a better performance than the conventional one.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2017.05a
• /
• pp.106-106
• /
• 2017

가스센서는 사내 및 산업 환경에서의 유독성 또는 폭발성 가스 검출, 환경 모니터링, 질병 진단 등 매우 다양한 응용분야에서 큰 관심을 가지고 있다. 반도체 금속산화물(SMOs) 기반의 센서 분야에서는 이들의 감도 및 선택성을 향상시키기 위해 많은 노력을 기울이고 있다. 이는 센서의 선택성을 부여하게 되면 다양한 가스들이 존재하는 환경에서도 검출자가 원하는 가스만의 응답을 얻을 수 있기 때문이다. 본 연구에서는 MOF(Metal-Organic Framwork) 기반 멤브레인으로 ZIF-8(Zeolitic Imidazolate Frameworks 구조들 중 하나) 멤브레인 쉘 층을 이용하여 ZnO 나노선에 형성하였다. ZnO 나노선은 VLS공정 (Vapor-Liquid-Solid)을 이용하여 패턴된 전극을 갖는 $SiO_2$-grown Si 웨이퍼 상에 성장되었고, 성장된 ZnO 나노선은 2-methyl imidazole과 methanol이 포함된 고용체에 넣고 폐쇄된 압력용기 속에서 가열시켜 얻게 된다. 이렇게 얻어진 ZIF-8@ZnO 나노선의 ZIF-8 멤브레인은 분자 체 구조(molecular sieving structure)를 갖게 되며, 이들의 pore 크기는 약 $3.4{\AA}$을 갖는다. 따라서 이보다 더 큰 동적 직경을(kinetic diameter) 갖는 가스 종은 이 멤브레인을 통과할 수 없음을 나타내므로 제작된 시편은 $H_2$(kinetic diameter : $2.89{\AA}$), $C_7H_8$(kinetic diameter : $5.92{\AA}$), 그리고 $C_6H_6$(kinetic diameter : $5.27{\AA}$) 가스들을 각각 사용함으로써 ZIF-8@ZnO 나노선의 센서 특성을 조사했으며, 보다 정확한 비교를 위해 순수한 ZnO 나노선 역시 동일한 조건에서 측정되었다. 결과를 통해, 수소 가스를 제외한 다른 가스들에 대해서는 반응을 하지 않고, 오직 수소 가스에 대해서만 반응을 나타냈으며, 순수 ZnO 나노선의 수소 감응도보다 낮은 감응도를 나타내었다. 이는 멤브레인 쉘 층을 형성함으로써 ZnO 나노선의 표면적이 감소해 가스 분자와의 접촉점을 감소시키기 때문이라고 판단된다. 이와 같은 MOF 멤브레인의 캡슐화 전략은 가스센서뿐 아니라 바이오 센서 및 광촉매 등과 같은 이온 선택성을 필요로 하는 다양한 응용분야에 적용될 수 있을 것으로 기대된다.

• The Journal of the Korea Contents Association
• /
• v.11 no.11
• /
• pp.274-285
• /
• 2011

This study deals with an analysis into the details of medical treatment and expenses by items of treatment as well as the factors related to the ratio between the medical treatment and expenses for 1583 patients who were hospitalized in and discharged from 2 general hospitals located at a city under the coverage of car insurance during the year 2009. As a result, there was statistically significant difference in the details of medical treatment and expenses by items of treatment as well as their composition ratio depending on the individual characters as sex, age and the number of days staying in hospital. Each medical institution should conduct a close analysis of its patients under the car insurance program as well as the factors related to medical expenses with a view to utilize them as basic data for mapping out plans for effective operation of its organization in consideration of the characters as a medicalinstitution.

• The Journal of the Korea Contents Association
• /
• v.15 no.12
• /
• pp.81-96
• /
• 2015

This study investigated the attributes of the popular programs by various broadcasting related platforms(on-air, VOD, SNS) and the relationship between the outcomes of these platforms in order to get the implications of broadcasting contents distribution strategy in multi-platform era. First, the study found that drama programs of territorial broadcasting showed the most high performance in on-air platform while comedy entertainment programs got the outstanding achievement in VOD platform. Second, although it had the low ratings in on-air platform, the program could be highly probable to get a great deal of VOD hits if it had attracted the younger audience. Knowledge programs showed the similar outcome between on-air and VOD platforms. Third, the study found that the factor which had a significant influence on VOD performance was the amount of buzz in SNS. These results suggest that broadcasting content distribution strategy in multi-platform era needs the understanding of the segmented target audiences of content and the analysis of trait of each platform.

• Applied Chemistry for Engineering
• /
• v.20 no.2
• /
• pp.191-194
• /
• 2009

Porous alumina prepared by anodization has been widely studied since it shows very regular nanostructures at inexpensive prices. In this article, porous alumina is obtained by anodization of aluminum in the oxalic acid. After the first formed oxide is selectively removed from the aluminum substrate, the hexagonal nanostructures on the fresh aluminum are converted to nanodots by the second anodization in boric acid. Nanodots are arrayed in the convex of the hexagonal nanostructures. The optimization condition for the fabrication of nanodots with a height of 20 nm is investigated in detail. Subsequently, a gold film is deposited on the nanodots, resulting in the formation of gold nanodots arrays which are probably interesting substrate for biosensor applications.