• Proceedings of the KIEE Conference
• /
• 1999.07e
• /
• pp.2377-2379
• /
• 1999

In order to analyze failure rates of underground transmission power cable systems in Korea, the survey has been performed for the failure cases of cables, joints, and terminations in CV, OF and POF cable systems which occurred from 1983 to 1998. During 16 years, the failure cases due to trips of the systems were 47 among the total 108 cases, These 47 cases could be divided into internal reasons(manufacture/installation, corrosion and degradation) of 16 cases and external reasons (external mechanical damages, lightning, fire. etc.) of 31 cases. For the 154 kV cable systems during 12 years from 1987 to 1998, total failure rate was 0.0057 [case/100C-km/year] and internal reason failure rate was 0.0020 [case/100C-km/Year], which is similar to those of foreign countries. Also, the many cases of internal reason failures occurred in the early stage after the operations due to incorrect installations. This implies that the installation process is very important and some diagnostic tests such as PD measurement are needed besides after laying test.

• Journal of Korean Society for Quality Management
• /
• v.47 no.3
• /
• pp.641-659
• /
• 2019

Purpose: Recently, the managing customer complaints properly has emerged as key source of competitive advantage in the large distribution industry. Effective customer complaint management helps firms minimize service failures and incense the capability to respond to customer's needs. Despite this importance, the in-depth prior study of a firm's service failures is very limited. Therefore, the actual service failure cases of large discount stores in Korea were analyzed in this study, and the types of service failures that occur at the service interface were identified. Method: Specifically, a total of 48,307 cases of customer complaints that have occurred in the past three years were collected from 1 January 2016 to 31 December 2018. Using 7 dimensions of service marketing mix. we have classified and analyzed systematically the service failure cases collected. Results: Among the cases of service failures, 34,921 (72.3%) cases were involved with the product factor, followed by 6,152 (12.7%) cases with person factor and 5,392 (11.2%) cases with process factor. Conclusion: By linking the main causes of service failure with the service marketing mix variables, this research presented a more systematic analytic model and verified by applying it to large domestic distribution company. Understanding the main factors affecting customer complaints n the large distribution industry can provide managers useful information and insight who want to achieve an effective customer complaint management.

• Journal of Chest Surgery
• /
• v.14 no.4
• /
• pp.319-323
• /
• 1981

To clarify the clinical spectrum of non-oliguric acute renal failure, we undertook a retrospective study of 16 cases of acute renal failure following trauma and surgery, 6 of whom were non-oliguric throughout their periods of azotemia. With the clinical symptoms, BUN, creatinine and some urinary diagnostic indexes, we analyzed the differences between non-oliguric and oliguric renal failure. And the results were: 1. The nonoliguric form [10 cases] was more common than oliguric [6 cases], especially post-traumatic failure. 2. The both types belonged to parenchymal renal failure by the U/P UN ratio and urinary Na concentration [Vertal, 1967]. 3. The non-oliguric form was lesser severe in urinary diagnostic indexes and clinically. The non-oliguric renal failure has better clinical course and prognosis, the failure to diagnose it is as dangerous as the failure oliguric renal failure.

• Journal of Chest Surgery
• /
• v.22 no.1
• /
• pp.123-133
• /
• 1989

A clinical evaluation was done on 182 cases of chest trauma which experienced at the Department of Thoracic and Cardiovascular Surgery, National Medical Center, from Sep. 1980 to Dec. 1987. 1] Of 182 cases, 125 cases resulted from non-penetrating chest trauma and 57 cases from penetrating wound. 2] The ratio of male to female was 4.87:1, and age groups between 3rd and 6th decade were 71.9%. 3] The most common causes of chest trauma were traffic accident in non-penetrating and stab wound by knife in penetrating cases. 4] Left thorax was the preferred site of chest injury. 5] The incidences of hemothorax, pneumothorax, and hemopneumothorax were 69.6% in non-penetrating and 91% in penetrating. 6] Rib fractures between 4th rib and 8th rib were 68.8% of total rib fracture cases and left side was preferred site. 7] Methods of treatment were conservative management in 24.7%, closed thoracostomy in 54.9%, open thoracotomy in 14.3%, and etc. 8] The incidence of complications, were 11.5% of total cases, and they were atelectasis [8 cases], empyema [3 cases], pneumonia [3 cases], acute renal failure [2 cases], lung abscess [1 case], and etc. 9] The overall mortality was 6%, and causes of death were hypovolemic shock, renal failure, hepatic failure, respiratory failure, septic shock, and etc.

• Journal of Chest Surgery
• /
• v.19 no.1
• /
• pp.92-100
• /
• 1986

Results of reoperation for tissue valve failure were presented with review of current knowledge. Through January 1986, 19 patients required reoperation: 18 had undergone mitral, 2 aortic, and 1 tricuspid valve. Primary tissue failure was the main cause of tissue valve failure: it occurred in 18 valves [15 mitral, 2 aortic, and 1 tricuspid] at a mean postoperative interval of 54-25 months [range 29-120]. During the same period, 2 patients required reoperation for prosthetic valve endocarditis, 1 for paravalvular leakage. The types of valves failed were 12 lonescu-Shiley valves, 5 Hancock valves, and 1 Carpentier-Edwards valve. All 6 patients younger than 15 years of age at first operation had been implanted with lonescu-Shiley valves and failed after a mean interval of 35 months. In contrast, 11 patients older than 15 years had been implanted with 5 Hancock, 6 lonescu-Shiley, and 1 Carpentier-Edwards valve initially, and eventually failed after mean intervals of 81, 53, 47 months each other. The kinds of valves used at reoperation were 8 lonescu-Shiley, 4 Bjork-Shiley, and 6 St. Jude Medical valves for primary tissue failure cases and 3 lonescu-Shiley valves for the other 3 cases. Overall mortality at reoperation was 10%: 5.6% for primary tissue failure, 50% for prosthetic valve endocarditis. In 15 cases [all mitral] primary tissue failure were caused by calcification associated with or without leaflet destruction or fibrous ingrowth, and in 2 cases [all aortic] caused by cusp perforation and tearing without any evidence of calcification. In conclusion: 1 primary tissue failure is the main cause of reoperation in patients with tissue valve failure; 2. the majority of the failed valves is in mitral position; 3. leaflet calcification is the leading pathology of primary tissue failure; 4, reoperation for tissue valve failure may be a major concern, although the mortality is low; 5. the limited durability of tissue valve suggests its use be restricted to selected cases.

• Asian Journal of Innovation and Policy
• /
• v.3 no.1
• /
• pp.25-49
• /
• 2014

We wanted to show the different group dynamics of factors for success and failure cases for technology commercialization in small technology-based firms. Existing studies are based on product level, project level, division level or firm level. We deal with technology level, and at small-technology-based firms. This is a longitudinal case study based on 8 cases from Korea. Our study on technology level is a first trial in success and failure studies unlike all existing studies. As a first step, we introduced new categories and factors such as technology attributes and CEO reflecting data, and especially a new concept of launch readiness level. Finally, we adopted correspondence analysis to show the group dynamics. The results are as follows; Technology factors are the most important factors. Second, resource-based factors are more critical in failure cases than success cases and technology factors are more critical to success.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.29 no.1
• /
• pp.116-126
• /
• 2016

Objectives: The purpose of these cases is to report the effects of oriental medicine on two patients with premature ovarian failure. Methods: Two patients who had amenorrhea and hot flashes caused by premature ovarian failure were treated by oriental medicine such as herb medication. We estimated the effects of treatments by follow-up measurements of serum hormone level, menstrual cycle and symptoms. Besides, follicle and endometrium were checked by ultrasonography for academic research.Results After treatments, their symptoms of premature ovarian failure were improved and the menstrual cycle resumed. And the level of serum Follicle Stimulating Hormone decreased and the level of serum E₂ increased.Conclusions Two cases shows that oriental medicine has effects on patients with premature ovarian failure by follow-up measurements of serum hormone level, menstrual cycle and symptoms.

• Clinical and Experimental Reproductive Medicine
• /
• v.21 no.2
• /
• pp.221-226
• /
• 1994

Copper T 380A intrauterine devices were inserted to nine thousand and nine hundred twenty women by 51 KAVS-member physicians since January 1, 1993 through December 31, 1993. This study was undertaken for the clinical analysis on a total of 9,920 women wearing Copper T 380A to grasp the effectivness as well as the expulsion rate due to a various side effects. The following features were the results of the study: 1. During the twelve months period, from January 1993 to December 1993, the largest number of IUD insertion per one physician is 740 cases and the smallest number 60 cases, the mean 195 cases. 2. After insertion of Copper T 380A, a total of 117 cases were removed the IUD;81 cases(0.8%) were due to extensive bleeding and 36 cases(O.36%) were due to pain. The pregnancy failure rate represented comparatively lower rate, 0.08% (8 cases) and the expulsion rate was 0.06%(6 cases). 3. The removal rate of Copper T 380A was different by physicians. The highest removal rate for bleeding was 3.13% and 13 physicians(25.5%) did not experience any bleeding cases. 4. For the removal rate for pain, 30 physicians(58.8%) did not experience any removal of IUD due to pain while 21 physicians(41.2%) removed IUD due to pain: 17 physiciansC33.4 %) had 0.1-1.5% of removal rate and 4 physiciansC7.0%) had 1.6-2.1% of removal rate. 5. A total of 43 physicians(84.3 %) did not experience any pregnancy failure case while 8 (15.7%) physicians was experienced pregnancy failure rate. Four physicians(7.8%) had 0.1-0.5% of pregnancy failure rate and 4 physicians had 0.6-1.0% of pregnancy failure rate. 6. Expulsion rate showed comparatively lower, 0.06% in this study. A total of 45 physicians (88.2%) did not experience any expulsion cases while 6 physicians(11.7%) had expulsion rate with the highest expulsion rate of 2.0%.

• Knowledge Management Research
• /
• v.16 no.2
• /
• pp.91-111
• /
• 2015

Social media marketing has gained attention from marketers due to the growing number of social media users. Marketers around the globe have a serious concern over how to utilize social media as a successful marketing tool. Many of them show a lack of understanding of the essential feature of social media and effective social media marketing strategies, which brings about a higher chance of social media marketing failures. Analyzing the failure cases of social media marketing is vital because it provides rich insights for marketing experts who have difficulty in developing effective social media marketing strategies. Therefore, this study conducted multiple case studies by selecting five failure cases of social media marketing which we defined as paradigmatic social media marketing failures which happened in the last five years in South Korea. From the case studies, we derived five successful social media marketing strategies. This study has a theoretical implication because it is the first to suggest effective social media marketing strategies based on the analysis on social media marketing failure cases. It also has a practical implication since it proposes specific social media marketing strategies which can help facilitate successful social media marketing.

• KIPS Transactions on Software and Data Engineering
• /
• v.9 no.11
• /
• pp.357-366
• /
• 2020

As the proportion and complexity of software embedded in aircraft increase, risk factors such as mission failure, function failure and performance failure due to software errors also increase. In the mission-critical software systems such as aircraft software, managing requirement traceability is essential to maintain the software systems with minimal period and cost. However, the development company is not accurately complying with the guideline for managing requirement traceability due to various reasons such as development cost and schedule. Therefore, it is not easy to systematically establish and maintain requirement traceability. In the paper, we analyze actual test cases of aviation software systems from the viewpoint of requirements traceability in order to learn if there are failure cases of test cases due to the absence of systematic traceability management activities. We also check the risks associated with the failure cases according to the type and severity of the cases. As a result of analyzing a total of 7 aircraft-mounted software, failure cases could be divided into three types: omission of requirements, lack of connection between requirements and test procedures, and omission of test procedures. There were a total of 18 failure cases, 6 for each type. The numbers of high, middle and low risks were 1, 13 and 4, respectively, where the number of middle risks is largest.