• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.168-175
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• 2006

An experimental study was conducted to investigate the effect of the morphology of CNT on the thermal conductivity of suspensions. The effective thermal conductivities of the samples were measured using asteady-state cut bar apparatus method. Enhancements based on the thermal conductivity of the base fluid are presented as functions of both the volume fraction and the temperature, Although functionalized SWNT produiced a more stable and homogeneous suspension, the addition of small amounts of surfactant to suspensions of 'as produced' SWNT demonstrated a greater increase in effective thermal conductivity than functionalized SWNT alone. The effective thermal conductivity enhancement corresponding to 1.0 percent by volume approached 10%, which was observed to be lower than expected, but more than twice the values, 3.5%, obtained for similar tests conducted using aluminum oxide suspensions. However, for suspensions of MWNT, the degree of enhancement was measured to be approximately 37%. It was postulated that the effect of clustering, resulting from the multiple heat-flow passages constituted by interconnecting neighboring CNT clusters, played an important role in significant enhancement of effective thermal conductivity.

• Journal of Practical Engineering Education
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• v.10 no.2
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• pp.89-94
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• 2018

In injection molding, the tool temperature has a great influence on the quality of the molded article. The appropriate temperature is determined by the molding material and the quality required for the molded part, and the important point is that the temperature should be stable. First, the tool temperature should be set in accordance with the quality required by the molded article within the range of the tool temperature conditions suitable for the material. That is, the tool temperature changes depending on the importance of the surface gloss of the molded article, shortening of the molding cycle, prevention of deformation, degree of shrinkage, ease of resin flow and the like. In order to improve practical tool technology, we propose a training model of the difficult process of tool temperature control which can be utilized in industry that design and manufacture injection mold.

• Earthquakes and Structures
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• v.16 no.4
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• pp.487-499
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• 2019

Energy-based seismic design of structures has gradually become prominent in today's structural engineering investigations because of being more rational and reliable when it is compared to traditional force-based and displacement-based methods. Energy-based approaches have widely taken place in many previous studies and investigations and undoubtedly, they are going to play more important role in future seismic design codes, too. This paper aims to compute the maximum earthquake energy input to elastic single-degree-of-freedom (SDOF) systems for selected real ground motion records. A data set containing 100 real ground motion records which have the same site soil profiles has been selected from Pacific Earthquake Research (PEER) database. Response time history (RTH) analyses have been conducted for elastic SDOF systems having a constant damping ratio and natural periods of 0.1 s to 3.0 s. Totally 3000 RTH analyses have been performed and the maximum mass normalized earthquake input energy values for all records have been computed. Previous researchers' approaches have been compared to the results of RTH analyses and an approach which considers the pseudo-spectral velocity with Arias Intensity has been proposed. Graphs of the maximum earthquake input energy versus the maximum pseudo-spectral velocity have been obtained. The results show that there is a good agreement between the maximum input energy demands of RTH analysis and the other approaches and the maximum earthquake input energy is a relatively stable response parameter to be used for further seismic design and evaluations.

• Korean Journal of Materials Research
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• v.31 no.10
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• pp.569-575
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• 2021

The reactivity evaluation of copper is performed using ethylenediamine, aminoethanol, and piperidine to apply organic chelators to copper etching. It is revealed that piperidine, which is a ring-type chelator, has the lowest reactivity on copper and copper oxide and ethylenediamine, which is a chain-type chelator, has the highest reactivity via inductively coupled plasma-mass spectroscopy (ICP-MS). Furthermore, it is confirmed that the stable complex of copper-ethylenediamine can be formed during the reaction between copper and ethylenediamine using nuclear magnetic resonance (NMR) and radio-thin layer chromatography. As a final evaluation, the copper reactivity is evaluated by wet etching using each solution. Scanning electron micrographs reveal that the degree of copper reaction in ethylenediamine is stronger than that in any other chelator. This result is in good agreement with the evaluation results obtained by ICP-MS and NMR. It is concluded that ethylenediamine is a prospective etch gas for the dry etching of the copper.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.821-824
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• 2009

Conformal mapping is useful to solve problems in physics, engineering and so on. This paper is to discuss the numerical conformal mapping from the unit disk onto Jordan region, which can be solved by Theodorsen equation. Wegmann's method has been known as the most efficient one for the Theodorsen equation. However, we found divergence through numerical experiments by the iterative method of Wegmann. The divergence occurs especially when some degree of difficulty is high. We analyze the cause of divergence and propose an improved method by applying a low frequency pass filter to Wegmann's method. By this proposed method we can get a stable convergence for all the problems which was unstable with the Wegmann's method.

• Archives of Craniofacial Surgery
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• v.23 no.6
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• pp.269-273
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• 2022

Naso-orbito-ethmoidal (NOE) fractures are complicated fractures of the mid-face. The treatment of NOE fractures is challenging and a comprehensive treatment strategy is required. We introduce a case of NOE fracture treated with open reduction and suspension sutures. A 28-year-old woman presented with a unilateral NOE fracture. To reduce the frontal process of the maxilla, a suspension suture was made by pulling the fragment using a double arm suture via a transcaruncular incision. The suture thread was placed in the horizontal plane. Another suspension suture on the inferior orbital rim assisted reduction procedure, and they passed through the overlying skin. The reduction alignment could be finely adjusted by tightening the transcutaneous suture threads while checking the degree of bone alignment through the subciliary incision. The two suture threads were suspended using a thermoplastic nasal splint. An additional skin incision on the medial canthal area, which would have resulted in a scar, could be avoided. Four months postoperatively, computed tomography showed an accurate and stable reduction. The patient was satisfied with her aesthetic appearance, and functional deficits were not present.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.5
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• pp.397-407
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• 2022

The informal economy is a large part of the urban economy. The informal economy accounts for about half of Pakistan's GDP. This research examined nine different areas of Rawalpindi's Central Business District's business sector (CBD). A survey of 404 respondents from 16 CBD marketplaces enables a comprehensive examination of who works in the informal and formal economic sectors, how much they earn, their goals, perception of their job, and their degree of similarity to the rest of the working population. Furthermore, the statistics illustrate the pro-cyclical connections between the informal economic sector and the formal economy. The Multinomial Logistic Regression (MLR) technique is used for the analysis. The MLR results indicated the informal economic sector holds positive relation with earning members in a family, business expertise, average business sale, and negative relation with education level, satisfaction with government tax policies, household expense, and average investment in the business. From a resilience standpoint, governance is considered an intentional collective action to preserve a stable system condition. Hence, the current study recommends tax reforms and government institution reorganization to mobilize the informal sector and make effective institutional governance.

• Journal of Environmental Science International
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• v.31 no.2
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• pp.181-193
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• 2022

The study was conducted to provide basic data for stable forest management according to climate change by identifying the ecological characteristics of Mt. Dalma warm temperate forest. 30 survey plots were established for vegetation structure analysis, and communities which classified by applying TWINSPAN analysis and DCA analysis techniques. Four plant communities were subdivided into Quercus acuta-Eurya japonica community, Quercus acuta community, Quercus salicina-Camellia japonica community, and Quercus acuta-Camellia japonica community. The tree layers were dominated by Quercus acuta and Quercus salicina, and the subtree layers were dominated by Camellia japonica and Eurya japonica, and the Sasa borealis. The species diversity index were in the range of 0.849 to 0.969, and the degree of Evenness index were 0.514 to 0.569, and the similarity index were 59.57 to 75.47%. The species composition in the community indicated that the deciduous broad-leaved and coniferous trees have already been eliminated in competition with evergreen broad-leaved trees. Tree species with good cold resistance such as Quercus acuta and Quercus salicina were dominant species under current climatic conditions, but the dominant species might be changed to more shade-tolerance evergreen broad-leaved through the succession.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.534-541
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• 2011

Risk evaluation approaches for bidding on international construction projects are typically partitioned into three stages: country selection, project classification, and bid-cost evaluation. However, previous studies are frequently under attack in that they have several crucial limitations: 1) a dearth of studies about country selection risk tailored for the overseas construction market at a corporate level; 2) no consideration of uncertainties for input variable per se; 3) less probabilistic approaches in estimating a range of cost variance; and 4) less inclusion of covariance impacts. This study thus suggests a three-staged risk evaluation model to resolve these inherent problems. In the first stage, a country portfolio model that maximizes the expected construction market growth rate and profit rate while decreasing market uncertainty is formulated using multi-objective genetic analysis. Following this, probabilistic approaches for screening bad projects are suggested through applying various data mining methods such as discriminant logistic regression, neural network, C5.0, and support vector machine. For the last stage, the cost overrun prediction model is simulated for determining a reasonable bid cost, while considering non-parametric distribution, effects of systematic risks, and the firm's specific capability accrued in a given country. Through the three consecutive models, this study verifies that international construction risk can be allocated, reduced, and projected to some degree, thereby contributing to sustaining stable profits and revenues in both the short-term and the long-term perspective.

• Journal of Arbitration Studies
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• v.34 no.2
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• pp.27-44
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• 2024

The lack of consistency and predictability of arbitral awards in the Investor-State Dispute Settlement ("ISDS") mechanism has long been a subject of criticism. In international investment disputes, arbitral tribunals have frequently come up with different interpretations and results on similar investment agreement provisions. The arbitral tribunal's inconsistent decisions raised concerns not only among the parties to the investment dispute but also amongthe arbitral tribunals in other cases, which ultimately led to legal inconsistencies in international investment law. Arbitration awards may have some degree of disagreement in interpretation. However, the systemic inconsistencies that pervade ISDS risk undermining the purpose of the investment agreement system, which is to provide a predictable and stable framework to protect andpromote foreign investment while maintaining a balance with host state regulations. Therefore, this study proposes a plan to resolve this discrepancy and review standards for practical application. Reform of the ISDS mechanism could be a viable option to reduce, to some extent, the inconsistencies in interpretation, if not completely eliminate them. Reforms such as establishingguidelines, promoting cooperation between arbitral tribunals, and codifying the norms of the agreement can provide a means of reducing interpretive inconsistencies and strengthening the legitimacy of the ISDS mechanism. Reforming the ISDS mechanism will require all stakeholders to carefully consider the issues and the scope, nature, and feasibility of eachpotential reform.