• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.4
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• pp.99-107
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• 2017

This paper proposes a battery model coefficient correction method for improving the accuracy of existing lithium battery equivalent models. BMS(battery management system) has been researched and developed to minimize shortening of battery life by keeping SOC(state of charge) and state of charge of lithium battery used in various industrial fields such as EV. However, the cell balancing operation based on the battery cell voltage can not follow the SOC change due to the internal resistance and the capacitor. Various battery equivalent models have been studied for estimation of battery SOC according to the internal resistance of the battery and capacitors. However, it is difficult to apply the same to all the batteries, and it tis difficult to estimate the battery state in the transient state. The existing battery electrical equivalent model study simulates charging and discharging dynamic characteristics of one kind of battery with error rate of 5~10% and it is not suitable to apply to actual battery having different electric characteristics. Therefore, this paper proposes a battery model coefficient correction algorithm that is suitable for real battery operating environments with different models and capacities, and can simulate dynamic characteristics with an error rate of less than 5%. To verify proposed battery model coefficient calibration method, a lithium battery of 3.7V rated voltage, 280 mAh, 1600 mAh capacity used, and a two stage RC tank model was used as an electrical equivalent model of a lithium battery. The battery charge/discharge test and model verification were performed using four C-rate of 0.25C, 0.5C, 0.75C, and 1C. The proposed battery model coefficient correction algorithm was applied to two battery models, The error rate of the discharge characteristics and the transient state characteristics is 2.13% at the maximum.

• Journal of Chest Surgery
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• v.40 no.5 s.274
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• pp.351-355
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• 2007

Background: Postinfarction ventricular septal rupture is associated with mortality as high as $85\sim90%$, if it is treated medically. This report documents our experience with postinfarction ventricular septal rupture that was treated surgically, Material and Method: We retrospectively reviewed the medical records of 11 patients who were operated on due to postinfarction ventricular septal rupture between August 1996 and August 2006. There were 4 men and 7 women, with a mean age of $70{\pm}11$ years (age range: $50\sim84$ years). The location of the rupture was anterior in 7 cases and posterior in 4 cases. The interval between the onset of acute myocardial infarction and the occurrence of the ventricular septal rupture was $2.0{\pm}1.3$ days (range: $1\sim5$ days). Operation was performed at an average of $2.4{\pm}2.7$ days (range: $0\sim8$ days) after the diagnosis of septal rupture. Preoperative intraaortic balloon pump therapy was performed in 10 patients. Result: The infarct exclusion technique was used in all cases. Coronary artery bypass grafting was done in 8 cases, with the mean number of distal anastomosis being $1.0{\pm}0.8$. There was one operative death. In 2 patients, reoperation was performed due to a residual septal defect. The postoperative morbidities were transient atrial fibrillation (n=7), paroxysmal supraventricular tachycardia (n=1), low cardiac output syndrome (n=3), bleeding reoperation (n=2), delayed sternal closure (n=2), acute renal failure (n=2), pneumonia (n=1), intraaortic balloon pump-related thromboembolism (n=1), and transient delirium (n=2). Nine patients have been followed up for a mean of $38{\pm}40$ months except for one follow-up loss. There have been 3 late deaths. At the latest follow-up, all 6 survivors were in a good functional class. Conclusion: We demonstrated satisfactory operative and midterm results with our strategy of preoperative intraaortic balloon pump therapy, early repair of septal rupture by infarct exclusion and combined coronary revascularization.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.141-155
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• 1997

The universe has its order of yang and yin : all creation are continuously generated, grow and die, which is the results of the harmonious operation by yang and yin. Among all creation, the human is one of the samjae(three bases of the world, which are heaved earth, and man) and he is from the combined sukhi(a superior khi) of yang and yin. And human life itself is basically a condensed jonghyul (life blood) and at the same time it is only a transient joining of sadae(the four elements of earth, air, fire and water). Yang and yin, the two axes of the world, therefore. are the most crucial and fundamental concept to explain the generation and extinction of alt creation, to understand people in time and space. to find out the reality of human life as an organism, and, at last, to observe the state of human health. If so, what is the most essential idea in yang and yin\ulcorner It is taegeuk(chungkhi) or tao(of one yang and one yin). If the property of heaven and earth is kongon, taegeuk is a khi and tao a principle. And it can be said that a human body is merely a union of hyung and khi, that human life is an essence of sambo, jeongkhishin, that human health is a harmoninzed coordination of yang and yin because it is from the combined sukhi of yang and yin. Hyung. a vessel for sambo, jeongkhishin, is at the bottom and shin is on the top : the personality and the disposition of individuals differ according to their working. Thus. on the basis of the above discussion. the following can be offered as some suggestions for Korean Nursing Theory. Though human beings are part of Nature, they are the most eminent microcosm among all creation. So, as a subjet for nursing, a person should be understood with khijok kyoryu rather than with logical thinking, then mutual trust between the patient and the nurse can be established. The health of a person depends on the harmony of yang and yin. To be healthy, a person should consider harmonization with Nature(including his surroundings) as well as a balanced human relationships in society. Moreover, it is crucial for each person to obtain hoshim as a method of mind control rather than to only treat the symptoms of disease.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1129-1135
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• 2013

In this, three types of natural gas were employed to investigate the effect of low-calorific natural gas on the performance of and emissions from a heavy-duty CNG engine. The performance and emission characteristics were analyzed by conducting a full-load test, WHSC mode test, and WHTC mode test. The results showed that the torque of low-calorific natural gas with $9,800kcal/Nm^3$ of higher heating value decreased by 4.4 compared to that of the current natural gas with $10,400kcal/Nm^3$ of heating value. With low-calorific fuels, CO, $CO_2$, and $NO_x$ emissions decreased. However, THC emissions increased. According to the WHSC and WHTC mode test results, the thermal efficiency increased and the emission characteristics showed a similar trend to the full-load test results. Low-calorific natural gases cause a decrease in torque at full-load operation conditions and an increase in hydrocarbon emissions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.3
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• pp.157-165
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• 2000

A small hydraulic winch system with an automatic tension control unit was designed to improve the work efficiency of coastal small vessels and the dynamic response characteristics of the winch system operated in the open loop condition was investigated. The inlet and the outlet pressures in hydraulic motor, the torque and the rotating speed of winch drum were measured as a function of time, and the behaviour in autotension mode for stepped load changes was analyzed. The results obtained are summarized as follows : 1. The developed winch system for coastal small vessels will result in better fishing with improved efficiency and lower manpower consumption by remote control of winch system. 2. The rotating delay times of winch drum for on/off operations of solenoid valve were 0.09 see at CW mode and 0.04 sec at CCW mode, respectively. After the solenoid valve was controlled, response characteristics were unstable slightly but showed good tracking behaviour over short time. 3. The driving torque of winch system in autotension mode was kept almost constant of 55.9 kgf·m, and 11.1 then the rotating speed of winch drum was kept almost constant of 5.1 rpm in the larger torque than 55.9 kgf·m and 11.1 rpm in the lower torque than that. 4. The 5% settling times in the transient response characteristics of autotension mode under rapid increasing and decreasing conditions of load were 0.12 sec and 0.2 sec, respectively, and then the rotating speeds were 11 rpm and 5.3 rpm, respectively. 5. The tracking behaviour of torque and rotating speed by remote control operation were stable within 0.23 sec at CW mode and 0.37 sec at CCW mode, respectively.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.598-603
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• 1998

Excessive sweating of the palms, axillae, and face has a strong negative impact on the quality of life for many people. The existing non-operative therapeutic options seldom give sufficient relief and have a transient effect. But a definitive cure can be obtained by upper thoracic sympathectomy. From June 1997 to October 1997, 117 cases of the needle (2 mm) thoracoscopic thoracic sympathectomies were performed in the Department of Thoracic and Cardiovascular Surgery in the Respiratory Center Yong-dong Severance Hospital in Seoul, Korea. We have followed up on 94 cases which include palmar hyperhidrosis (n=85), facial hyperhidrosis(n=5) and axillary hyperhidrosis(n=4). There were 42 males and 52 females whose ages ranged from 14 to 63 years(median:23 years). The T2 ganglia and T3-4 ganglia were excised by electrocuting with a hook and endoscissors and were removed for histologic examination. There have been no mortalities or life-threatening complications. The surgical results were classified as excellent(much improvement,very dry) in 93.6%, good(some improvement, minimally wet) in 2.1%, and fair(slight improvement, still wet) in 4.2%. Five patients(5.3%) required closed thoracostomy drainage because of pneumothorax in the immediate postoperative day. Horner's syndrome occurred in one case. The compensatory sweating occurred in 67 cases(71.2%) and was embarrassing in 21 cases(22.3%) and disabling in 9 cases(9.6%) of these cases. Primary failure occurred in one case. The patient with primary failure underwent successful operation. Fifty-one patients had concomitant hyperhidrosis. Our experiences indicate needle thoracoscopic sympathectomy is a very effective, safe, and time- saving procedure for essential hyperhidrosis.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.2
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• pp.169-175
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• 2020

This paper studied the SET situation in VLSI because the electronic devices exposed to SET can indicate irregular operation and output errors. The SET environment was established using the exponential static wave (iexp) in the fold-cascode comparator. The comparator was experimented with how it affected it by the SET. In a folded comparator that did not enter the SET situation, the propagation delay was measured at 0.26㎲ and the gain was 0.649. The MOSFET close to the output stage was measured sensitively in the folded comparator that entered the SET situation. And propagation delay was calculated from 0.36 to 0.37㎲ and the gain was 0.649. The mid-position MOSFET was calculated from 0.28 to 0.30㎲ and the gain was 0.649. The MOSFET, which is farthest from the output stage from the folded comparator, was calculated with the propagation delay between 0.25 and 0.26㎲ and the gain of 0.649. In SET situations, the MOSFET close to the output portion of the folded comparator was sensitive. And at the MOSFET far from the output, the same results were obtained as a normal folded comparator without the SET input.

• Journal of Korean Neurosurgical Society
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• v.30 no.8
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• pp.992-997
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• 2001

Objectives : Essential hyperhidrosis is a common condition characterized by excessive body sweating. Excessive sweating beyond what is necessary to maintain normal body temperature need not be considered pathological unless it interferes with one's occupation and/or life-style. The existing non-operative therapeutic options seldom give sufficient relief or show a transient effect. In this regard, the thoracic sympathectomy may provide a definitive cure. In the past, surgical procedures were highly invasive and caused significant morbidity, but the minimally invasive thoracoscopic procedure provided detailed visualization of sympathetic ganglia and is associated with minimally postoperative morbidity. Nowadays, thoracoscopic transthoracic sympathectomy is accepted as the treatment of choice for essential hyperhidrosis. In palmar hyperhidrosis, however, the level of sympathetic chain to be blocked has been somewhat obscure. It is assumed that the incidence of compensatory hyperhidrosis may closely related to the extent of thoracic sympathectomy. Material & Methods : To compare the results of posterior midline approach with endoscopic sympathectomy, and the results of T2 with T2, 3 sympathectomy or sympathicotomy, we retrospectively studied 62 patients treated for palmar hyperhidrosis between September 1993 and May 2000. We reviewed medical records and recently interviewed the patients by telephone calls. Results : The treatment effect of T2 sympathectomy is no different from T2, 3 sympathectomy. But, the incidence of compensatory hyperhidrosis is less in the T2 sympathectomy group than the T2, 3 sympathectomy group. Conclusion : Thoracoscopic sympathectomy is considered a simple, safe, and effective method for treating palmar hyperhidrosis, with a shorter operation time, fewer hospital days, and a better cosmetic result, as compared with the open approaches. However, sympathicotomy seems to provide the advantages of a limited extent of denervation and the resultant decrease of compensatory hyperhidrosis compared to sympathectomy.

• Journal of Korean Neurosurgical Society
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• v.45 no.4
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• pp.224-230
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• 2009

Objective : We aimed to analyze clinical and radiological outcomes retrospectively in patients with basilar apex aneurysms treated by coiling or clipping. Methods : Outcomes of basilar bifurcation aneurysms were assessed retrospectively in 77 consecutive patients (61 women, 16 men), ranging in age from 25 to 79 years (mean, 53.7 years) from 1999 to 2007. Results : Forty-nine patients out of 77 patients (63.6%) presented with subarachnoid hemorrhages of the 49 patients treated with coiling, 27 (55.1 %) showed complete occlusion of the aneurysm sac. Of these, 13 patients (26.5%) developed coil compaction on angiographic or MRI follow-up, with recoiling required in 9 patients (18.4%). Procedural complications of coiling were acute infarction in nine patients and the bleeding of the aneurysms in six patients. The remaining 28 patients underwent microsurgery : twenty-six of these (92.9%) with microsurgery followed up with conventional angiography. Complete occlusion of the aneurysm sac was achieved in 19 patients (73.1%). Operation-related complications of microsurgery were thalamoperforating artery injuries in three patients, retraction venous injury in two, postoperative epidural hemorrhage (EDH) in one, and transient partial or complete occulomotor palsy in 14 patients. Glasgow Outcome Scores (GOS) were 4 or 5 in 21 of 28 (75%) patients treated with microsurgery at discharge, and at 6 month follow-up, 20 of 28 (70.9%) maintained the same GOS. In comparison, GOS of four or 5 was observed in 36 of 49 (73.5%) patients treated with coiling at discharge and at 6 month follow-up, 33 of 49 patients (67.3%) maintained the GOS from discharge. Conclusion : Basilar top aneurysms were still challenging lesions based on our series. Endovascular or microsurgery endowed with its inborn risks and procedural complications for the treatment of basilar apex aneurysms individually. Microsurgery provided better outcome in some specific basilar apex aneurysms. For reaching the most favorable outcome, endovascular modality as well as microsurgery was inevitably considered for each specific basilar apex aneurysm.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.149-155
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• 1992

55 consecutive anatrophic nephrolithotomies on 53 patients performed between July, 1983 and June, 1990 were reviewed. The patients(36 male and 19 female) ranged in age from 3 to 72years. The operation time averaged 219.8 minutes with a range of 120-330 minutes, and the ischemic time ranged between 20 and 90 minutes, with a mean of 43.5 minutes. Postoperative complications developed in 18 patients, which were such as persistent urinary tract infection in 5cases(9.4%), atelectasis in 4(7.5%), transient urine leak in 2(3.8%), delayed bleeding in 2(3.8%) and urinary retention in 2(3.8%), Postoperative residual stones were identified in 15(27.3%), but in 8 of these 15patients stones were delivered spontaneously and thus 48 of 55 cases(87.3%) became stone free, The recurrence of stone was noted in 2 out of 48 patients during the short followup period. Anatrophic nephrolithotomy seems to be an effective method compared to other procedure because of decreasing recurrence of stone by complete stone removal and reconstruction of abnormal collecting system.