• 한국식품과학회지
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• 제23권6호
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• pp.732-738
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• 1991

Corsoy 79 대두를 8-와 24-mesh 입자 크기의 전지 대부분으로 분쇄하였다. 입자크기 분석으로 8mesh 전지 대부분은 기하학적 평균 크기 와 표준편차가 24 mesh 전지 대두분 보다 켰다. 분포계수는 두 전지 대두분 모두 동일하여서 거의 완벽하게 원하는 입자 크기로 분쇄됨을 알 수 있었다. 대두의 분쇄 시작부터 그 후 24시간의 짧은 저장기간 동안 두 전지 대부분에서 유지를 추출하여 가수분해와 산화에 의한 유지의 변패를 측정하였다. 유지의 과산화물가나 conjugated diene의 증가는 없었으며, 수분함량 10.7%, 이하에서 hexanal 함량증가도 없었다. 수분함량 14.9% 이상에서 유지산패는 수분함량과 저장기간의 증가로 그 값이 증가하였다. 대두의 수분함량이 4%에서 18%로 증가함에 따라서 가수분해에 의한 산패 즉 유리지방산가는 0.06%만이 증가하였으므로 실질적으로 분쇄후 24시간 저장동안 전지대부분 변질에 어떠한 영향도 주지 못하였다. 이러한 결과에서 원료대두의 수분함량이 11%이하이면 전지 대부분으로 분쇄하고 그 후 24시간동안 저장하여도 유지나 향미의 변패에 어떠한 영향도 주지 못함을 발 수 있었다.

• 한국환경보건학회지
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• 제41권5호
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• pp.327-334
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• 2015

Objectives: In order to review both the effects of sewage sludge dewaterability and deodorizing ability in the existing advanced sewage treatment process, BIO-CLOD (a solidified mixture of 10% Bacillus concentrate and inorganics) was used as an inorganic conditioner effective for deodorization treatment in addition to the removal of organic matter and nutritive salts. Methods: Sludge dewaterability was evaluated using specific resistance to filtration (SRF) experiments with six agitators and two types of commercially available BIO-CLOD; one that is made by grinding solid matter (powdered BIO-CLOD) and one that has been obtained by sieving a separation with a particle diameter of 100 mesh (100 mesh BIO-CLOD). For deodorization odor treatment experiments, 20 g of commercially available solid BIO-CLOD was submerged in four liters of sewage sludge and mixed and agitated for 45 days. Results: When BIO-CLOD was injected into sewage sludge to experimentally compare specific resistance to filtration (SRF), the optimum amount of BIO-CLOD to be injected was shown to be 2% w/v and the SRF value in this case was $1.35{\times}10^{12}m/kg$. pH changes following BIO-CLOD injection were within 6.5-7.0. By 14 days after submerging BIO-CLOD into the sewage sludge to evaluate its deodorizing ability, $H_2S$ decreased by 68% and methyl mercaptan decreased by 74%. By 45 days after the submergal, both items decreased by 100%, indicating deodorizing ability. Conclusion: To compare the levels of dewaterablity of sewage sludge at different particle sizes of inorganic conditioner, powdered BIO-CLOD, particle size 100 mesh BIO-CLOD, and bentonite were tested. It could be seen that as the powdered BIO-CLOD increased, the precipitability increased up to 62% in 30 minutes. As an inorganic conditioner, BIO-CLOD was identified as a stable sludge conditioner that does not affect pH.

• 한국구조물진단유지관리공학회 논문집
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• 제8권2호
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• pp.205-211
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• 2004

본 연구의 목적은 CFM으로 전단 보강된 보의 실험으로 CFM의 전단 보강 효과를 평가하는 것으로서, 실험 변수는 메쉬의 배치 방향, 정착 클립의 개수, 전단 스팬비이다. 실험에서, 전체적으로 모르터와 RC보에서의 부착 파괴는 가력 초기부터 발생하여 최대 내력의 약 60% 정도에서 완전히 파괴되었으며, 전단 내력에 대한 CFM의 기여도는 CFM 최대 인장 강도의 약 19.6%인 것으로 나타났다. 또한 전단 스팬비가 1.0인 경우 대각선 방향으로 메쉬를 배치할 때 전단 보강 효과가 높은 것으로 나타났으나, 1.5인 시험체의 경우, 정착 클립의 개수가 많을 경우 보강 효과가 높은 것으로 나타났다.

• 한국환경농학회지
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• 제28권4호
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• pp.378-385
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• 2009

Arsenic (As) is known to be very toxic and carcinogenic to human beings. Arsenic contaminated soil was collected from a timber mill site at Busan Metropolitan City, Korea, where chromated copper arsenate (CCA) had been used to protect wood from rotting caused by insects and microbial agents. The soil was stabilized using both natural oyster shells (NOS) and calcinated oyster shells (POS). The calcination of natural oyster shells was accomplished at a high temperature in order to activate quicklime from calcite. Two different oyster shell particle sizes (-#10 mesh and -#20 mesh) and curing periods of up to 28 days were investigated. The stabilization effectiveness was evaluated based on the Korean Standard Test (KST) method (1N HCl extraction). The stabilization results showed that the POS treatment was more effective than the NOS treatment at immobilizing the As in the contaminated soils. A significant As reduction (96%) was attained upon a POS treatment at 20 wt% and passed the Korean warning standard of 20 mg/kg ('Na' area). However, an As reduction of only 47% (169 mg/kg) was achieved upon a NOS treatment at 20 wt%. The -#20 mesh oyster shells seem to perform better than the -#10 materials. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results showed that As immobilization was strongly associated with Ca and O in the presence of Al and Si.

• 대한기계학회논문집B
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• 제27권11호
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• pp.1618-1629
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• 2003

The effects of the interaction between flow field and heat transfer caused by the longitudinal vortices are experimentally investigated using a five hole probe and a transient liquid crystal technique. The test facility consists of a wind tunnel with vortex generators protruding from a bottom surface and a mesh heater. In order to control the strength of the longitudinal vortices, the angle of attack of vortex generators used in the present experiment is 20$^{\circ}$, and the spacing between the vortex generators is 25mm. The height and cord length of the vortex generator is 20mm and 50mm, respectively. Three-component mean velocity measurements are made using a f-hole probe system, and the surface temperature distribution is measured by the hue capturing method using a transient liquid crystal technique. The transient liquid crystal technique in measuring heat transfer has become one of the most effective ways in determining the full surface distributions of heat transfer coefficients. The key point of this technique is to convert the inlet flow temperature into an exponential temperature profile using the mesh heater set up in the wind tunnel. The conclusions obtained in the present experiment are as follows: The two maximum heat transfer values exist over the whole domain, and as the longitudinal vortices move to the farther downstream region, these peak values show the decreasing trends. These trends are also observed in the experimental results of other researchers to have used the uniform heat flux method.

• 한국정보과학회논문지:정보통신
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• 제36권6호
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• pp.481-491
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• 2009

본 논문에서는 라이브 미디어 스트리밍 서비스를 위한 하이브리드 P2P 오버레이 구조를 제안한다. 제안하는 구조는 가까운 지역에서 유사한 대역폭을 가진 피어들로 구성된 메시 오버레이와 메시 오버레이 구조를 기반으로 하여 세션 참여 안정성을 가진 피어들을 구성된 트리 오버레이로 이루어져 있다. 제안하는 방안에서는 메시 오버레이와 트리 오버레이를 유기적으로 활용함으로써 트리 오버레이 구조의 견고성과 메시 오버레이 구조의 롱지연을 보완한다. 또한, 트리 오버레이에서 동일 지역 내 업링크 대역폭이 높은 피어를 미디어 소스 피어 가까이에 위치시키며 트리의 깊이를 줄이고 넓를 넓혀서 스트림 전달의 지연을 최소화한다. 시뮬레이션을 통해, 제안하는 방안과 기존 연구의 성능을 확장성, 서비스 품질 등의 측면에서 평가해 보았다.

• Journal of Korean Neurosurgical Society
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• 제42권4호
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• pp.317-325
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• 2007

Objective : The purpose of the study was to determine the clinical effects of anterior radical debridement on a series of patients with spontaneous spinal infection. Methods : We retrospectively analyzed the clinical characteristics of 32 patients who underwent surgical treatment from January 2000 to December 2005 in our department. The average follow-up Period was 33.4 months (range, 6 to 87 months). Thirty-two patients presented with the following : 23 cases with pyogenic spondylitis, eight with tuberculous spondylitis and one with fungal spondylitis. The indications for surgery were intractable pain, failure of medical management, neurological impairment with or without an associated abscess, vertebral destruction causing spinal instability and/or segmental kyphosis. Results : The study included 15 (46.9%) males and 17 (53.1%) females ranging in age from 26 to 75 years (mean, 53.1 years). Diabetes mellitus (DM) and pulmonary Tbc were the most common predisposing factors for pyogenic spondylitis and tuberculous spondylitis. Staphylococcus aureus (13%) was the main organism isolated. The most prevalent location was the lumbar spine (75%). Changes in the pain score, Frankel's classification, and laboratory parameters demonstrated a significant clinical improvement in all patients. However, there were recurrent infections in two patients with tuberculous spondylitis and inappropriate debridement and intolerance of medication and noncompliance. Autologous rib, iliac bone and allograft(fibular) were performed in most patients. However, 10 patients were grafted using a titanium mesh cage after anterior radical debridement. There were no recurrent infections in the 10 cases using the mesh cage with radical debridement. Conclusion : The findings of this study indicate that surgery based on appropriate surgical indications is effective for the control of spinal infection and prevention of recurrence with anterior radical debridement, proper drug use and abscess drainage.

• Nuclear Engineering and Technology
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• 제52권7호
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• pp.1545-1556
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• 2020

Recently, the International Commission on Radiological Protection (ICRP) has developed the Mesh-type Reference Computational Phantoms (MRCPs) for adult male and female to overcome the limitations of the current Voxel-type Reference Computational Phantoms (VRCPs) described in ICRP Publication 110 due to the limited voxel resolutions and the nature of voxel geometry. In our previous study, the MRCPs were used to calculate the dose coefficients (DCs) for idealized external exposures of photons and electrons. The present study is an extension of the previous study to include three additional particles (i.e., neutrons, protons, and helium ions) into the DC library by conducting Monte Carlo radiation transport simulations with the Geant4 code. The calculated MRCP DCs were compared with the reference DCs of ICRP Publication 116 which are based on the VRCPs, to appreciate the impact of the new reference phantoms on the DC values. We found that the MRCP DCs of organ/tissue doses and effective doses were generally similar to the ICRP-116 DCs for neutrons, whereas there were significant DC differences up to several orders of magnitude for protons and helium ions due mainly to the improved representation of the detailed anatomical structures in the MRCPs over the VRCPs.

• 한국분말재료학회지
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• 제17권5호
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• pp.365-372
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• 2010

The evolution of sinterability, microstructure and mechanical properties for the spark plasma sintered(SPS) Ti from commercial pure titanium(CP-Ti) was studied. The densification of titanium with 200 mesh and 400 mesh pass powder was achieved by SPS at $750{\sim}1100^{\circ}C$ under 10 MPa pressure and the flowing $H_2$+Ar mixed gas atmosphere. The microstructure of Ti sintered up to $800^{\circ}C$ consisted of equiaxed grains. In contrast, the growth of large elongated grains was shown in sintered bodies at $900^{\circ}C$ with the 400 mesh pass powder and the lamella grains microstructure had been developed by increasing sintering temperature. The Vickers hardness of 240~270 HV and biaxial strength of 320~340 MPa were found for the specimen prepared at $950^{\circ}C$.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 제11차 KACG 학술발표회 Crystalline Particle Symposium (CPS)
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• pp.285-309
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• 1996

Non oxide ceramics such as nitrides of transition metals have shown significant potential for future economic impact, in diverse applications in ceramic, aerospace and electronic industries, as refractory products, abrasives and cutting tools, aircraft components, and semi-conductor substrates amid others. Combustion synthesis has become an attractive alternative to the conventional furnace technology to produce these materials cheaply, faster and at a higher level of purity. However he process os highly exothermic and manifests complex dynamics due to its strongly non-linear nature. In order to develop an understanding of this process and to study the effect of operational parameters on the final outcome, numerical modeling is necessary, which would generated essential knowledge to help scale-up the process. the model is based on a system of parabolic-hyperbolic partial differential equations representing the heat, mass and momentum conservation relations. The model also takes into account structural change due to sintering and volumetric expansion, and their effect on the transport properties of the system. The solutions of these equations exhibit steep moving spatial gradients in the form of reaction fronts, propagating in space with variable velocity, which gives rise to varying time scales. To cope with the possibility of extremely abrupt changes in the values of the solution over very short distances, adaptive mesh techniques can be applied to resolve the high activity regions by ordering grid points in appropriate places. To avoid a control volume formulation of the solution of partial differential equations, a simple orthogonal, adaptive-mesh technique is employed. This involves separate adaptation in the x and y directions. Through simple analysis and numerical examples, the adaptive mesh is shown to give significant increase in accuracy in the computations.