Decision Supporting Methodology and System Based on Theory of Constraints for Making an Optimal Product Portfolio Strategy in Shipbuilding Industry

Shipbuilding is a typical ‘build to order’ industry. It has a business model that generates revenues from building various ships and offshore products in accordance with owner’s requirements at each production stage. Under uncertainty in shipping market, it is very essential for the shipbuilder to prepare the fast and competitive decision for product portfolio strategy in order to maximize contribution margin by exploiting production facilities and constraints. TOC(theory of constrains) proposed by Dr. goldratt in 1979 has been evolved into a management philosophy with practices and principles spanning a multitude of operations management sub-disciplines.[1] In this study, we introduce the unique decision supporting methodology for the optimal product portfolio sets based on TOC. This methodology is established by adopting the concept of Drum Buffer Rope (DBR)[2] in constraints planning and Throughput Account (TA)[3][4][5] in management accounting of TOC. In addition, Decision Supporting System (DSS)[6] is implemented by applying this methodology. This DSS system provides a throughput estimator with reflecting the cost structure of shipbuilding industry and a resource simulator built on heuristic algorithms to operate major constraint-resources in shipyard such as dock, quay and pre-erection area etc. Several examples are presented to show that the proposed methodology and system can effectively support the strategic decision-making process of a global shipbuilding company

C-Band GaN Dual-Feedback Low-Noise Amplifier MMIC with High-Input Power Robustness

In this paper, using the 0.2 μm ETRI GaN HEMT process, we developed a C-band GaN dual-feedback low-noise amplifier MMIC for an RF receiver module that requires high-input power robustness. By applying a feedback microstrip line at the source of the transistor and series resistor-capacitor (RC) feedback between the gate and the drain of the transistor, we obtained stable amplifier operation and a compromised impedance trace for both input impedance matching and noise matching while suppressing performance degradation of the maximum available gain and minimum noise figure. The developed low-noise amplifier MMIC, which implements simple matching circuits by using biasing elements as matching elements, had a linear gain of more than 21.4 dB and a noise figure of less than 1.91 dB in the wide bandwidth of 4.3–7.4 GHz. Under the single-tone power test, the low-noise amplifier MMIC had an output P1dB of 14.3–20.1 dBm, and the two-tone intermodulation distortion measurement exhibited an input third-order intercept point (IIP3) of 2.2–5.6 dBm in the same frequency range as the above

Overexpression of Arabidopsis thaliana brassinosteroid-related acyltransferase 1 gene induces brassinosteroid-deficient phenotypes in creeping bentgrass

Brassinosteroids (BRs) are naturally occurring steroidal hormones that play diverse roles in various processes during plant growth and development. Thus, genetic manipulation of endogenous BR levels might offer a way of improving the agronomic traits of crops, including plant architecture and stress tolerance. In this study, we produced transgenic creeping bentgrass (Agrostis stolonifera L.) overexpressing a BR-inactivating enzyme, Arabidopsis thaliana BR-related acyltransferase 1 (AtBAT1), which is known to catalyze the conversion of BR intermediates to inactive acylated conjugates. After putative transgenic plants were selected using herbicide resistance assay, genomic integration of the AtBAT1 gene was confirmed by genomic PCR and Southern blot analysis, and transgene expression was validated by northern blot analysis. The transgenic creeping bentgrass plants exhibited BR-deficient phenotypes, including reduced plant height with shortened internodes (i.e., semi-dwarf), reduced leaf growth rates with short, wide, and thick architecture, high chlorophyll contents, decreased numbers of vascular bundles, and large lamina joint bending angles (i.e., erect leaves). Subsequent analyses showed that the transgenic plants had significantly reduced amounts of endogenous BR intermediates, including typhasterol, 6-deoxocastasterone, and castasterone. Moreover, the AtBAT1 transgenic plants displayed drought tolerance as well as delayed senescence. Therefore, the results of the present study demonstrate that overexpression of an Arabidopsis BR-inactivating enzyme can reduce the endogenous levels of BRs in creeping bentgrass resulting in BR-deficient phenotypes, indicating that the AtBAT1 gene from a dicot plant is also functional in the monocot crop.111Ysciescopu

Duodenal Mucosa-Associated Lymphoid Tissue Lymphoma: A Case Report

Primary duodenal mucosa associated lymphoid tissue (MALT) lymphoma is very rare, and little is known about its clinical course or effective treatment. We describe a case of primary duodenal MALT lymphoma that was resistant to Helicobacter pylori (H. pylori) eradication and regressed after chemotherapy with cyclophosphamide, vincristine, and prednisolone (CVP). A 71-year-old woman was referred to our department because of epigastric pain and dyspepsia. Gastroduodenoscopy revealed an irregular mucosal nodular lesion with ulceration extending from the bulb to the second portion of the duodenum. Histopathological examination of a biopsy specimen disclosed low-grade MALT lymphoma composed of atypical lymphoid cells with lymphoepithelial lesion. Abdominal CT scans revealed 0.5 to 1.5 cm lymph nodes in the peritoneal cavity, suggestive of lymph node metastasis. We successfully eradicated H. pylori but did not see signs of remission. We administered systemic CVP chemotherapy every 3 weeks. After 6 courses of CVP, the patient achieved complete remission and was followed up without recurrence for about a year

Successful Treatment of Stereotactic Body Radiation Therapy Combined with Transarterial Chemolipiodolization for Hepatocellular Carcinoma with Biliary Obstruction

Conventional radiation therapy (RT) is a widely recognized treatment for hepatocellular carcinoma (HCC). However, conventional RT plays only a limited role in HCC treatment because of its low efficacy and the low tolerance of the liver for this modality. Stereotactic body radiation therapy (SBRT) was recently developed and represents the most advanced radiation therapy technique currently available. It can deliver a high dose in a short time to well-defined hepatic tumors, with rapid dose fall-off gradients. We believe that SBRT with transarterial chemolipiodolization (TACL) may prove promising as a combined treatment modality for HCC due to its precision and relative safety. Here we present a case of successful treatment of advanced HCC with obstructive jaundice using this combined modality

Photovoltaic Performance of Dye-Sensitized Solar Cells Containing ZnO Microrods

At an elevated temperature of 90°C, a chemical bath deposition using an aqueous solution of Zn(NO3)2·6H2O and (CH2)6N4 resulted in the formation of both nanoflowers and microrods of ZnO on F-doped SnO2 glass with a seed layer. The nanoflowers and microrods were sensitized with dyes for application to the photoelectrodes of dye-sensitized solar cells (DSSCs). By extending the growth time of ZnO, the formation of nanoflowers was reduced and the formation of microrods favored. As the growth time was increased from 4 to 6 and then to 8 h, the open circuit voltage (Voc) values of the DSSCs were increased, whilst the short circuit current (Jsc) values varied only slightly. Changes in the dye-loading amount, dark current, and electrochemical impedance were monitored and they revealed that the increase in Voc was found to be due to a retardation of the charge recombination between photoinjected electrons and I3− ions and resulted from a reduction in the surface area of ZnO microrods. A reduced surface area decreased the dye contents adsorbed on the ZnO microrods, and thereby decreased the light harvesting efficiency (LHE). An increase in the electron collection efficiency attributed to the suppressed charge recombination counteracted the decreased LHE, resulting in comparable Jsc values regardless of the growth time. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.1