This study deals with replacement analysis of deteriorated equipment for improving productivity of production system. Frequent breakdown of the deteriorated equipment causes a situation that reduces productivity such as low product quality, process delay, and repair cost. However, the replacement of new equipment will be required a high initial investment cost, so it is important to analysis the economic feasibility. Therefore, we analyze the effect of the production system due to the aging effect of the equipment and the feasibility of equipment replacement based on the economic analysis. The process flow, working time, logistics movement, etc. are analyzed in order to build the simulation modeling for a ship and land switchboard production system. Using numerical examples, the economic feasibility analysis of equipment replacement through replacement of existing deteriorated equipment and additional arrangement of new facilities is performed.

Globally, colon cancer is increased gradually and known as one of the major causes of cancer death. Stevia, a substitute of sugar, is known to have many components including alpha-tocopherol and anthocyanin etc, as antioxidants. This study's purpose is to investigate whether stevia plant extract can have a protective effect against colon carcinogenesis induced by azoxymethane (AOM) and dextran sodium sulfate (DSS) in mice. Total 30 male ICR mice were divided into 2 groups; AOM/DSS treatment (control group), AOM/DSS + stevia extract (0.5%, in drinking water). After acclimation for 1 week, five weeks old mice received three intraperitoneal AOM (10 mg/kg b.w.) injections weekly for 3 weeks (0–2nd weeks of the experiment) and 2% DSS as drinking water for the next one week. AIN-76A purified rodent diet and 0.5% stevia extract water were supplied to the animals for 6 weeks. The colons of mice were collected and the number of aberrant crypt foci (ACF) and aberrant crypts (ACs) in colonic mucosa were counted after staining with methylene blue. Malondialdehyde (MDA) concentration in feces were determined. The numbers of ACF and ACs were significantly (p<0.01) decreased in stevia-treated group compared with the control group. The MDA concentration in feces was also significantly (p<0.01) decreased in stevia-treated group compared with the control group. In histopathology of colonic epithelium, hyperplasia of colonic epithelium was less observed in steviatreated group. These results indicate that stevia has a protective effect against colon carcinogenesis induced by AOM/DSS in mice and further study needs to illustrate the protective mechanisms.

뽕나무깍지벌레는 복숭아, 매실, 뽕나무 등 31종의 기주식물을 가해하는 기주범위가 광범위한 난방제 해충으로 알려져 있다. 2017년도에 뽕나무깍지벌레는 5월 상순부터 부화를 시작하여 암컷성충 1마리가 75.5개(47~159개)의 알을 낳으며 모든 알이 부화하는데 약 19일이 소요되었고, 부화율은 약 87%였다. 반면에 2018년도에는 4월 하순부터 부화를 시작하여 암컷성충 1마리가 49.4개(12~71개)의 알을 낳으며 모든 알이 부화하는데 13일이 소요되었으며, 부화율은 약 72%를 보였다. 부화한 약충들은 이동 후 5월 중순부터 고착약충으로 되고, 6월 중순부터 2세대 성충이 활동하기 시작하였다. 부화약충기에 약제를 살포하여 살충효과를 조사한 결과, 살충률이 100%인 반면에, 고착약충기 에는 살충율은 2.7%로 살충효과가 낮은 것을 확인하였다.

Background and Purpose: The Ankle-Brachial Index (ABI) is the ratio of blood pressure in the lower legs to that in the arms. The intima-media thickness (IMT) of extracranial carotid arteries determined by B-mode ultrasound is a measurable index of the presence of atherosclerosis. A low ABI and a high carotid IMT are independently related to increased risk of cardiovascular events. This study examined the association between carotid IMT and ABI in patients with ischemic stroke. Materials and Methods: Retrospectively, 116 hospitalized patients with ischemic stroke were recruited. Using a pulse wave velocity ABI device along with carotid duplex sonography, we measured carotid IMT and ABI and investigated the correlation between average values. Results: There was a significant difference in carotid IMT between the normal and abnormal ABI groups (P=0.0262). The group with an abnormal ABI was more than five times as likely to have increased carotid IMT as the group with a normal ABI (age, sex-adjusted OR 5.67 (95% CI 1.85~17.38)). The ABI and carotid IMT showed a weak inverse linear correlation in patients with ischemic stroke (correlation coefficient −0.378 after adjusting for age and sex). Conclusion: Our study suggests that an abnormal ABI is associated with a high carotid IMT in patients with ischemic stroke.

Yellow alkaline noodles were prepared with various Korean wheat cultivars including different protein and amylose contents and made from two types of noodle machines. Korean food companies and restaurants generally used noodle machine made in Korea, whereas research institutes mainly practiced with noodle machine made in Japan. Noodle dough sheet from Korean machine showed 5% higher water absorption and 30 min shorter resting period than the noodle dough from Japanese machine because of the difference of size and weight of roller in two types of the machines. In 15 Korean wheat cultivars, thickness of noodle dough sheet was positively correlated with protein content and mixograph water absorption regardless of both types of the machines. Cooked noodles from Korean machine showed higher hardness and lower springiness than noodles from Japanese noodle machine, but difference in cohesiveness of cooked noodles was not found between two different noodle machines. In the three Korean wheat cultivars with different protein content, thickness of noodle dough sheet was also positively correlated with protein content, SDS sedimentation volume and mixing time of mixograph in both types of the machines. The more protein content increased, the more hardness of cooked noodles increased regardless of both types of the machines. However, springiness and cohesiveness of cooked noodles were not significantly correlated with protein content. In waxy and partial waxy wheat cultivars, lightness of noodle dough sheet from Korean noodle machine positively correlated with amylose content. Amylose content and setback in pasting properties were positively correlated with hardness, springiness, and cohesiveness of cooked noodles while both damaged starch and breakdown were negatively correlated with those.

In this study, the internal structure of a Heumgyeonggak-nu (欽敬閣漏) was designed, and the power transmission mechanism was analyzed. Heumgyeonggak-nu is an automated water clock from the Joseon Dynasty that was installed within Heumgyeonggak (欽敬閣), and it was manufactured in the 20th year of the reign of King Sejong (1438). As descriptions of Heumgyeonggak-nu in ancient literature have mostly focused on its external shape, the study of its internal mechanism has been difficult. A detailed analysis of the literature record on Heumgyeonggak-nu (e.g., The Annals of the Joseon Dynasty) indicates that Heumgyeonggaknu had a three-stage water clock, included a waterfall or tilting vessel (欹器) using the overflowed water, and displayed the time using a ball. In this study, the Cheonhyeong apparatus, water wheel, scoop, and various mechanism wheels were designed so that 16 fixed-type scoops could operate at a constant speed for the water wheel with a diameter of 100 cm. As the scoop can contain 1.25 l of water and the water wheel rotates 61 times a day, a total of 1,220 l of water is required. Also, the power gear wheel was designed as a 366-tooth gear, which supported the operation of the time signal gear wheel. To implement the movement of stars on the celestial sphere, the rotation ratio of the celestial gear wheel to the diurnal motion gear ring was set to 366:365. In addition, to operate the sun movement apparatus on the ecliptic, a gear device was installed on the South Pole axis. It is expected that the results of this study can be used for the manufacture and restoration of the operation model of Heumgyeonggak-nu.