• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권10호
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• pp.465-470
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• 2005

In this paper. an experimental study, for method of increasing the efficiency of electrostatic precipitator for the collection of submicron-sized particles has been studied. All AC electric field was used to induce agglomeration of bipolory charged Particles. .4 bipolar AC-agglomeration system. consisted with a multineedle-mesh discharge system with a control grid, was proposed and investigated. Systematic experiments were carried out to investigate the agglomeration ratio of the AC-agglomeration system as a function of the different grid spacings and grid resistances for the submicron particles generated from liquid prorhane gas burning. The agglomeration ratios, which indicate the particle numbers before and after agglomeration of the test particles in number concentration base, were found to be 0.87, 1.80, 3.86, 9.50 and, 11.00 times for the particle sizes of 0.3. 0.5, 0.7, 1.0, and 2.0$\mu$m at applied voltage of 3.5kV, respectively which showed that the fine particle numbers were decreased while the larger particle numbers were increase greatly.

• 무역학회지
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• 제47권3호
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• pp.157-175
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• 2022

This study calculates agglomeration indices of manufacturing specialization and diversification in different regions of South Korea. Two types of agglomeration indices are introduced into the spatial durbin model (SDM) to analyzes the effects of manufacturing agglomeration in Korea on CO₂ emission intensity. The subjects of this study are 17 regions of South Korea , and the research period is from 2013 to 2019. This study also uses partial differential to analyze the direct and spillover effect of specialization and diversification agglomeration on CO₂ emission intensity. From the perspective of direct effect, the results reveal that specialization agglomeration is an important factor contributing to Korea's CO₂ emissions. However, diversification agglomeration has an obvious CO₂ emission reduction effect. From the perspective of spillover effect, this study finds that specialization agglomeration in one region can also contribute to CO₂ emissions in nearby regions. However, the development of diversification agglomeration in one region can have CO₂ emission reduction spillover effect on neighboring regions.

• 대한지리학회지
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• 제48권1호
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• pp.72-86
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• 2013

산업집적은 경제지리학에서 오랫동안 연구되어온 주제 중의 하나이며 지금까지 다양한 방법을 통해 산업집적 현상을 설명하고 이의 영향을 평가해왔다. 하지만 시계열 데이터를 이용해 집적의 추이를 살펴본 연구는 아직 활발히 이루어지지 않고 있다. 본 연구는 지난 29년 간의 데이터를 이용해 사례로 선정된 산업들의 집적 정도를 평가하고 이러한 시계열 패턴과 도로 네트워크의 확장이 어떠한 인과관계를 맺고 있는 지 살펴보고 있다. 집적 정도를 측정한 결과 사례로 선정된 산업의 종사자들은 지리적으로 균등하게 분포되지 않고 있었다. 또한 사례 산업들 간에 공통된 시계열적 변화 특성은 나타나지 않았으나 각 산업의 발전 단계 및 비즈니스 환경 변화가 개별 산업의 집적 정도에 영향을 주고 있는 것으로 보이고 있다. 집적 정도와 도로교통망 사이의 관계를 살펴보기 위해 각 산업 별로 Granger causality test를 실시하였고 도로 교통망이 산업 집적에 영향을 주고 있음을 몇몇 사례를 통해 확인할 수 있었다. 그러나 이와 반대의 경우 혹은 상호 간에 영향을 주는 사례도 나타나 교통망과 산업집적이 보다 복잡한 관계를 맺고 있음을 보여준다.

• 한국경제지리학회지
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• 제11권3호
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• pp.302-318
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• 2008

1990년대 이후 산업 집적 혹은 지역혁신 관련 연구들은 폭발적으로 증가해 왔고, 그와 관련된 다양한 이론적 논의들이 활발하게 전개되고 있다. 그럼에도 불구하고, 경제지리학의 가장 핵심적인 연구 분야의 하나인 산업 집적과 관련된 용어와 개념들의 구체성은 오히려 결여되고 있어, 새로운 학문적 조류와 환경 변화에 대응한 이론 체계의 발전에 걸림돌이 되고 있다. 이에 본 논문에서는 지식기반경제 혹은 학습경제로의 전환을 상징적으로 나타내는 경제활동의 공간적 실체인 집적 및 클러스터와 관련된 용어와 개념 그리고 이론들을 주요 연구 문헌들의 고갈을 토대로 검토하였는바, 그 핵심적 주장은 다음과 같다. 첫째, 집적과 클러스터의 용어 및 개념적 구분이 명확히 이루어질 필요가 있다. 클러스터는 집적의 다양한 존재 형태 가운데 일부를 나타내는 개념임에도 불구하고 포괄적인 의미로 사용됨으로써 개념적 불명료성과 혼동을 가중시키고 있다. 둘째, 집적지, 혹은 클러스터에 대한 개념적 정의를 명확하게 하지 앓은 결과, 다양한 형태로 존재하는 집적지의 유형을 구분하는데 있어서도 혼란이 초래되고 있다. 다수의 연구에서 그들이 사용한 집적지 관련 용어에 대한 개념정의를 명확하게 하지 않고 유형 구분을 함으로써 집적지 유형 구분에 대한 의의를 반감시키거나 해석상의 오류를 유발하는 문제점을 노출하고 있다. 셋째, 산업 집적지 혹은 클러스터 관련 이론들 간의 수렴 현상이 나타나면서 이론들 간의 차별성과 정체성이 상실되는 문제점이 나타나고 있다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권2호
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• pp.150-155
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• 2001

It has been observed that water, which is absolutely essential for enzyme activity, can induce the agglomeration of enzyme particles in organic media. Although enzyme agglomeration is significant in that it usually reduces enzyme activity and stability, little attention has been paid to the quantitative analysis of enzyme agglomeration behavior in nonaqueous biocatalytic systems. In this study, the effect of water and silica gel on enzyme agglomeration were investigated using Candida rugosa lipase and cyclohexane as a model enzyme and an organic medium. The extent of enzyme agglomeration was quantified by sieve analysis of freeze-dried agglomerates. Increasing the water content of the medium increased the size of the enzyme agglomerates, and it was found that water produced during the esterification reaction could also promote the agglomeration of enzyme particles suspended in organic media. On the other hand, the size of the enzyme agglomerates was remarkably reduced in the presence of silica gel at the same water content. We also show that this increase in the size of enzyme agglomerates results in lower reaction rates in organic solvents.

• 한국연소학회지
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• 제8권2호
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• pp.41-49
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• 2003

Ultrasonic field of 28kHz with sound pressure level 162dB has been employed to agglomerate the fine soot particle produces in a diffusion flame in a chamber. The agglomeration process has been investigated with digital camcorder and analysed in terms of the decrease of number density with exposure time. From the observation of agglomeration process, the initial agglomeration has been carried out during the short time, and it has been dominated by the orthokinetic collision. Thereafter, a slower agglomeration mechanism, driven by acoustic streaming in the chamber takes over and agglomeraters grew to diameters of several millimeters were levitated at the pressure node of the acoustic wave. And, the circular disk shape of large agglomeraters with the rotational and translational motion is observed.

• Journal of Dairy Science and Biotechnology
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• 제40권3호
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• pp.134-142
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• 2022

Protein-enriched dairy powder is widely consumed to promote muscle synthesis. Recently, in Korea, elderly people have also begun consuming protein powder products to prevent muscle loss. However, these protein-enriched powders have poor flowability and hydration properties because of the fine particles of spray-dried milk protein powder. Therefore, in this study, the fluidized bed agglomeration process was used to solve these problems. The rheological and physical properties of milk protein isolate (MPI)/skim milk powder (SMP) mixtures were effectively improved via fluidized bed agglomeration. The particle size of the MPI/SMP mixtures significantly increased from 35.7-58 ㎛ to 118-136 ㎛, the flowability level improved from fair (21.4-26.3) to good (15.7-16.3), and the cohesiveness level changed from intermediate (1.27-1.36) to low (1.18-1.19) after fluidized bed agglomeration. In addition, the wetting time of the agglomerated MPI/SMP mixtures was effectively reduced to 4.67-58.3 s by fluidized bed agglomeration. These findings may be useful for manufacturing protein-enriched dairy powders with good instant properties.

• 대한지리학회지
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• 제48권5호
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• pp.629-650
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• 2013

본 연구에서는 '신산업집적'에 관한 우리나라의 지리학적 연구 동향을 고찰하고 과제를 제시하고자 하였다. 최근의 산업집적 연구는 새로운 '시각'에서의 전형적인 사례에 대한 설명이 중심이었다. 그 결과 산업집적에 대한 분석틀의 정립과 이론화의 간과라는 문제점을 안고 있다. 이를 해결하기 위해서는 신산업집적론에서 강조하는 비경제적 요인과 기존 입지론의 경제적 요인을 통합하는 분석틀을 정립하고, 이를 통한 집적지의 존립기반 메커니즘의 규명과 일반화에 대한 연구가 활성화되어야 한다. 특정 스케일의 경제 공간 내에서의 주체 간의 네트워크와 집적과 관계된 지역 자체의 사회문화적 조건에 대한 지나친 집착에서 벗어나야 한다. 그리고 클러스터 정책과 같은 산업집적지의 활성화에 대한 학술적 연구가 보다 강화되어야 할 것이다. 이러한 연구과제를 효과적으로 수행하기 위한 산업집적지의 연구자들 간의 보편적 이해와 공동 학습의 장이 활성화되기를 기대한다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.203-206
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• 2009

Agglomeration of catalysts is known as one of the major degradation mechanisms. Reforming of liquid fuel, which requires high temperature over $800^{\circ}C$, accelerates agglomeration of catalysts. In this work, The effects of agglomeration on catalysts activity in partial oxidation reforming conditions were investigated. Metal supported catalysts(Pt-CGO, Ru-CGO) were compared to perovskite-structured catalysts(NECS-P1, NECS-P2). High thermal stability of perovskite-structured catalysts was reported. Micro-reactor installed in electric furnace was used. its Temperature was raised from $800^{\circ}C$ to $1000^{\circ}C$ to accelerate agglomeration effect. To measure rate of agglomeration, BET analysis and CO pulse chemisorption were conducted on catalysts exposed to $1100^{\circ}C$. Metal supported catalysts showed degradation at $1000^{\circ}C$ and The rates were different according to metal supported. On the other hand perovskite-structured catalysts showed no degradation at $1000^{\circ}C$.

• 한국경제지리학회지
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• 제11권3호
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• pp.375-388
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• 2008

The early studies on the cultural industries had mainly emphasized the viewpoint of "efficiency" based on the "flexible specialization" theory, but they have gradually shed light on the viewpoint of "creativity": creative human resources and various networks generating creative energies. Despite the importance of these studies, it is impossible to explain every cultural industrial agglomeration phenomena from specific and few viewpoints due to the diversity of each cultural industry. This study describes the dissimilarity of agglomeration factors between the Japanese animation and home video game industries which form salient agglomeration in the same region. Both industries share similar characteristics with industrial agglomeration of SMEs in Tokyo and close inter-firm relationships. However, they differ in their historical development paths and each firm's behavior and strategy because of their own distribution systems and production processes. In particular, the difference in distribution systems clearly affects whether a company values "efficiency" factors of agglomeration advantage or "creativity" factors of that in case of locational choice. The distribution sector of the cultural industry, compared with the production sector, has a tendency to value profitability rather than creation itself. Therefore, a cultural industry with the strong distribution sector tends to form the industrial system emphasizing profitability. The Japanese animation firm is apt to choose its location from the perspective of efficiency, which easily contributes to profitability, because television broadcasting stations are strong distribution sector. Conversely, the Japanese game firm chooses its location from the perspective of creativity due to the absence of strong distribution sector.