• Journal of the Korean Society for Precision Engineering
• /
• 제22권9호
• /
• pp.194-201
• /
• 2005

Recently, as Rapid Prototyping is attracting people's attention, many peoples are actively participating in the research on STL format. The STL files are transformed to be input for RP after modeling in CAD system. When the shape, however, needs to be changed or edited, it is impossible without the original data. So, if the original data is lost, new modeling is required. Therefore, this study suggests a way to edit the shape in STL format and to make the Boolean operation possible between the original and edited shapes. In addition, the reliability was confirmed after going over the errors of the edited data.

• Journal of Chest Surgery
• /
• 제24권11호
• /
• pp.1090-1097
• /
• 1991

Between January 1981 and January 1991, 554 patients underwent prosthetic valve replacement. A bioprosthetic valve was replaced in 238 cases and mechanical valve 316 cases. Thirty-eight patients underwent 40 reoperations for repair or replacement, an average of 53.6 months after initial implantation. There were 21 women and 19 men, aged 12 to 60 years[mean 35.3]. A bioprosthetic valve was implanted in 31 cases and a mechanical valve in 9 cases for initial operation. Indications for reoperation were primary tissue failure in 23 cases[57.5%], endocarditis in 9[22.5%], periprosthetic leak in 4[10%]. and valve thrombosis in 4[10%]. Operations performed included 5 aortic valve replacements, 26 mitral valve replacement, 8 double valve replacements, and 1 thrombectomy. A mechanical valve was replaced in 33 cases[84.6%] and a bioprosthesis in 6[15.4Zo] for reoperation. A second reoperation was required in 2 patients. Surgical mortality was 10% . Among the 34 early survivors followed-up for an average of 19.8 months. there was 1 late death and 3 were lost to follow-up. Among the 30 late survivors being followed up, 28[93.3%] remained in New York Heart Association Class I or II and two in Class III [6.7%].

• Kyungpook Mathematical Journal
• /
• 제49권3호
• /
• pp.435-450
• /
• 2009

On page 366 of his lost notebook [15], Ramanujan recorded a cubic continued fraction and several theorems analogous to Rogers-Ramanujan's continued fractions. In this paper, we derive several general formulas for explicit evaluations of Ramanujan's cubic continued fraction, several reciprocity theorems, two formulas connecting V (q) and V ($q^3$) and also establish some explicit evaluations using the values of remarkable product of theta-function.

• Journal of the Korean Operations Research and Management Science Society
• /
• 제31권3호
• /
• pp.81-96
• /
• 2006

We consider a rental company that dynamically manages Its capacity level through capacity addition and return While serving customer with its own capacity, the company expands its capacity by renting items from an outside source so that it can avoid lost opportunities of rental which occur when stock is not sufficient. If stock becomes sufficiently large enough to cope with demands, the company returns expanded capacity to the outside source. Formulating the model into a Markov decision problem, we identify an optimal capacity management Policy which states when the company should expand its capacity and when it should return expanded capacity after capacity addition. Since it is intractable to analytically find the optimal capacity management policy and the optimal size of capacity expansion, we present a numerical procedure that finds these optimal values based on the value iteration method. Numerical analysis is implemented and we observe monotonic properties of the optimal performance measures by system parameters, which are meaningful in developing effective heuristic policies.

• Korean Management Science Review
• /
• 제18권1호
• /
• pp.79-88
• /
• 2001

We often feel the necessity to communicate with members involved in a project to remote discuss business activities, needs for the fast file transfer, and check the existence of members to talk with. There are some commercial applications in these problems. However, in addition to those existing functions, this study focuses especially on adding couple of functions such as automatic responding function, in which a sender of a message automatically knows if a receiver checks the message. Its application is that a project leader sends an important message and later on can check at his desk the fact that who have checked their messages. The prototype application, build in this study, will check the correctness of every sub-function, and then the interface of inter-sub-functions, finally the integrity of the entire system, so that important information will not be lost among members of a project in the real world situation.

• Journal of Chest Surgery
• /
• 제20권1호
• /
• pp.171-176
• /
• 1987

Takayasu`s arteritis is one of chronic inflammatory disease characteristically involving the aorta and its major branches. Symptoms and signs of the disease are various depending on the involved area. We experienced a surgical case of Takayasu`s arteritis mainly involving both renal arteries with renovascular hypertension in a 13 year old girl. Hypertension was not controlled by medical treatment including diuretics and captopril [160/140 mmHg]. Aortogram showed severely stenosed right renal artery, nearly obstructed left renal artery and not visulalized superior mesenteric artery. Angioplasty was performed for the right renal artery but aorta-renal bypass graft with greater saphenous vein was inevitable for the left renal artery. Blood pressure was controlled sufficiently with some adjunct of captopril postoperatively [130/90 mmHg]. While the patient was discharged with much improvement, she was lost follow up and died of not identified definitive cause 3 months later.

• Journal of the Korean Society of Physical Medicine
• /
• 제2권1호
• /
• pp.85-91
• /
• 2007

Purpose : The purpose of this study is understanding of Rett Syndrome. Rett Syndrome is a common developmental - neurologic disorder that has been reported almost exclusively in female. Recently mutations in the gene encoding X-linked methyl-CpG binding protein 2 (MECP2) have been identified as the cause of Rett syndrome. Consistent with the diagnostic criteria, hand skills, verbal or non - verbal communication skills and common motor skills were lost during regression. Regression most commonly occurred between 12 and 18 months of age. Methods : This is a literature study with books, articles, web site for Rett syndrome international association. Results : There is a continuing need to further elucidate the pre- and post - regression features of Rett syndrome. Rett syndrome need to physical therapy, musical therapy, special education and medical interventions. Conclusion : There has not been therapeutic method to the root of Rett syndrome but our goal is relaxation of symptom and physical therapist's study of Rett syndrome.

• Journal of Pharmaceutical Investigation
• /
• 제9권4호
• /
• pp.23-28
• /
• 1979

The effect of maltitol admininstration to rat was studied on breakdown of ${\alpha}-glycoside$ linkage with intestinal mucosa or pancreatic enzymes and induction of hepatic polyol dehydrogenase activities. Maltitol was contained as 13% or 26% in diet, and was administrated to rat for 9 weeks. This report carried out that ${\alpha}-glycoside$ linkage of maltitol was not hydrolyzed with pancreatic enzymes and intestinal mucosa. Maltitol dehydrogenase was not obeserved in liver cytoplasm, and hepbtic sorbitol dehydrogenase was not induced by maltitol administsation. Also, the effect of maltitol on aging of aluminum hydroxide gel, prepared by the reaction of aluminum chloride solution with strong ammonia solution to final pH 7.0, was studied by potentiometric titration, pH and acid-consuming capacity. Gel containing 1% or 2% maltitol was lost less than 2% of their acid-consuming capacity during a 120 days aging period compared with a loss of more than for an identical gel without maltitol and gel containing 0.5% maltitol.

• Proceedings of the Korean Information Science Society Conference
• /
• 한국정보과학회 2002년도 봄 학술발표논문집 Vol.29 No.1 (A)
• /
• pp.217-219
• /
• 2002

TCP has been designed and tuned as a reliable transfer protocol far wired links. However, it incurs end-to-end performance degradation in wireless environments where packet loss is very high. TCP HACK(Header Checksum Option) is a novel mechanism proposed to improve original TCP in lossy link. It presents an extension to TCP that enables TCP to distinguish packet corruption from congestion in losssy environments. TCP HACK performs well when the sender receives the special ACKs correctly, hut if the ACKs are also lost much, the efficient of TCP HACK will net be prominent. In this paper we present an extension to TCP HACK, which can perform well even when the ACKs are much corrupted.

• Journal of the Korean Society of Marine Environment & Safety
• /
• 제6권1호
• /
• pp.57-67
• /
• 2000

All crude oil carries a little of water, sand, and mineral sediment molecules tightly bounded with hydrocarbons. The result is the gradual precipitation of these heavier elements into thick, granular petroleum by products known as crude oil sludge. The oily sludges in ship tanks and in storage facilities have to be treated efficiently in order to keep the security and the capacity of storage facilities, to protect a serious environmental pollution, and to retrieve lost resource. The oily sludge treatment system should be designed to satisfy requirements mentioned in safe work condition. As a basic study, in this paper, an oily sludge treatment system by ultrasonic waves was proposed. Then, the features of ultrasonic energy and recovery of sludge with ultrasonic waves are investigated by experiments. As results, we found that ultrasonic waves are a new energy to flow oil sludge environment-friendly in safe work condition. In addition, it was shown that ultrasonic energy is more efficient than thermal energy in treating oil sludge, and that the volume of wastes for disposal is reduced remarkably.